WO2024068996A1

WO2024068996A1 - Anti-sars-cov-2 antibodies and use thereof in the treatment of sars-cov-2 infection

Info

Publication number: WO2024068996A1
Application number: PCT/EP2023/077174
Authority: WO
Inventors: Giuseppe Pantaleo; Craig W. FENWICK; Didier P. Trono; Priscilla TURELLI
Original assignee: Ecole Polytechnique Federale de Lausanne EPFL; Centre Hospitalier Universitaire Vaudois CHUV
Current assignee: Ecole Polytechnique Federale de Lausanne EPFL; Centre Hospitalier Universitaire Vaudois CHUV
Priority date: 2022-09-30
Filing date: 2023-09-29
Publication date: 2024-04-04
Anticipated expiration: 2025-03-30

Abstract

The disclosure provides antibodies, or antigen-binding fragments thereof, and use thereof in prophylaxis, treatment and/or attenuation of a SARS-CoV-2 virus infection.

Description

ANTI-SARS-COV-2 ANTIBODIES AND USE THEREOF IN THE TREATMENT OF SARS-COV-2 INFECTION

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to European Application No. EP22199188, filed September 30, 2022; U.S. Provisional Application No. 63/506,285, filed June 05, 2023; and U.S. Provisional Application No. 63/506,352, filed June 05, 2023; each of which is hereby incorporated by reference in its entirety.

REFERENCE TO AN ELECTRONIC SEQUENCE LISTING

[0002] The contents of the electronic sequence listing (SWIS_006_03WO_SeqList_ST26.xml; Size: 63,844 bytes; and Date of Creation: September 27, 2023) are herein incorporated by reference in its entirety.

FIELD

[0003] The present disclosure provides antibodies, antigen-binding fragments thereof, and use thereof in prophylaxis, treatment and/or attenuation of a SARS-CoV-2 virus infection.

BACKGROUND

[0004] Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19) was first reported in December 2019. Since then, SARS-CoV-2 has emerged as a global pandemic with an ever-increasing number of severe cases requiring specific and intensive treatments that threatens to overwhelm healthcare systems. While it remains unclear why COVID-19 patients experience a spectrum of clinical outcomes ranging from asymptomatic to severe disease and mortality, the COVID- 19 pandemic is a major challenge for governments, businesses, healthcare systems and people around the globe seeking ways to safely return to work/healthcare/travel/leisure. Testing for this highly infectious and often asymptomatic disease is burdensome with limited availability; treatments and vaccines are still emerging and not completely proven. Indeed, there are now several vaccines in clinical trials that demonstrate a high level of efficacy, however there is still no data indicating the durability of this vaccine induced protection. In addition, it is likely that at-risk individuals that includes the elderly population and immunosuppressed subjects (e.g., patients undergoing cancer therapy and those that have undergone an organ transplants) will only have a partial or transient protection induced by these vaccines. Thus, in the ongoing COVID-19 pandemic, there is a large unmet medical need for therapeutic interventions that can protect at- risk individuals, be of significant importance to protect individuals that are less able to mount an effective anti-SARS-CoV-2 immune response following vaccination and treat those already infected with the virus.

SUMMARY

[0005] In some embodiments, the present disclosure provides an antibody or antigen-binding fragment thereof that binds to the Spike protein of a Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), wherein the antibody or antigen-binding fragment thereof comprises: a variable heavy chain CDR1 (HCDR1) comprising an amino acid sequence selected from SEQ ID No: 9, 12, 15, 18, and 44; a variable heavy chain CDR2 (HCDR2) comprising an amino acid sequence of SEQ ID No: 10, 13, 16, 19, and 45; a variable heavy chain CDR3 (HCDR3) comprising an amino acid sequence selected from SEQ ID No: 11, 14, 17, 20, 46, 66, 67, 68, and 69; a variable light chain CDR1 (LCDR1) comprising an amino acid sequence selected from SEQ ID No: 21, 24, 27, 30, and 47; a variable light chain CDR2 (LCDR2) comprising an amino acid sequence selected from SEQ ID No: 22, 25, 28, 31, and 48; and a variable light chain CDR3 (LCDR3) comprising an amino acid sequence selected from SEQ ID No: 23, 26, 29, 32, and 49.

[0006] In some embodiments, the antibody or antigen-binding fragment thereof comprises: a HCDR1 comprising an amino acid sequence of SEQ ID No: 9, a HCDR2 comprising an amino acid sequence of SEQ ID No: 10, a HCDR3 comprising an amino acid sequence of SEQ ID No: 11, a LCDR1 comprising an amino acid sequence of SEQ ID No: 21, a LCDR2 comprising an amino acid sequence of SEQ ID No: 22, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 23.

[0007] In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 1, and a light chain variable domain (VL) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 5. In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 1, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 5.

[0008] In some embodiments, the antibody or antigen-binding fragment thereof comprises a HCDR1 comprising an amino acid sequence of SEQ ID No: 12, a HCDR2 comprising an amino acid sequence of SEQ ID No: 13, a HCDR3 comprising an amino acid sequence of SEQ ID No: 14, a LCDR1 comprising an amino acid sequence of SEQ ID No: 24, a LCDR2 comprising an amino acid sequence of SEQ ID No: 25, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 26.

[0009] In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No:

2, and a light chain variable domain (VL) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 6. In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 2, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 6.

[0010] In some embodiments, the antibody or antigen-binding fragment thereof comprises a HCDR1 comprising an amino acid sequence of SEQ ID No: 15, a HCDR2 comprising an amino acid sequence of SEQ ID No: 16, a HCDR3 comprising an amino acid sequence SEQ ID No: 17, a LCDR1 comprising an amino acid sequence of SEQ ID No: 27, a LCDR2 comprising an amino acid sequence of SEQ ID No: 28, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 29.

[0011] In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No:

3, and a light chain variable domain (VL) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 7. In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 3, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 7. In some embodiments, the HCDR3 comprises an amino acid substitution selected from S99A, G108A, and/or G108S relative to SEQ ID NO: 17. In some embodiments, the VH sequence is selected from SEQ ID Nos: 60-65.

[0012] T In some embodiments, the antibody or antigen-binding fragment thereof comprises a HCDR1 comprising an amino acid sequence of SEQ ID No: 18, a HCDR2 comprising an amino acid sequence of SEQ ID No: 19, a HCDR3 comprising an amino acid sequence of SEQ ID No: 20, a LCDR1 comprising an amino acid sequence of SEQ ID No: 30, a LCDR2 comprising an amino acid sequence of SEQ ID No: 31, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 32. [0013] In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 4, and a light chain variable domain (VL) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 8. In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 4, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 8.

[0014] In some embodiments, the antibody or antigen-binding fragment thereof comprises a HCDR1 comprising an amino acid sequence of SEQ ID No: 44, a HCDR2 comprising an amino acid sequence of SEQ ID No: 45, a HCDR3 comprising an amino acid sequence of SEQ ID No: 46, a LCDR1 comprising an amino acid sequence of SEQ ID No: 47, a LCDR2 comprising an amino acid sequence of SEQ ID No: 48, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 49.

[0015] In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 42, and a light chain variable domain (VL) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 43. In some embodiments, the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 42, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 43.

[0016] In some embodiments, the antibody or antigen-binding fragment thereof is a fully human antibody or antigen-binding fragment thereof.

[0017] In some embodiments, the antibody or antigen-binding fragment thereof binds to an epitope within the receptor binding domain (RBD) or the N-terminal domain (NTD).

[0018] In some embodiments, the antibody or antigen-binding fragment thereof neutralizes SARS-CoV-2. In some embodiments, the antibody or antigen-binding fragment thereof inhibits the fusion of SARS-CoV-2 and host cell membrane. In some embodiments, the antibody or antigen-binding fragment thereof is cytotoxic to a SARS-CoV-2 infected host cell.

[0019] In some embodiments, the antibody or antigen-binding fragment thereof is a multivalent antibody comprising (a) a first target binding site that specifically binds to an epitope within the spike polypeptide, and (b) a second target binding site that binds to an epitope on a different epitope on the spike polypeptide or a different molecule. In some embodiments, the antibody or the antigen-binding fragment thereof further comprises a variant Fc constant region.

[0020] In some embodiments, the antibody or antigen-binding fragment thereof of is a chimeric antibody, a humanized antibody, or humanized antibody. In some embodiments, the antigenbinding fragment is a single-chain antibody, Fab, or Fab2 fragment. In some embodiments, the antibody or antigen-binding fragment thereof is detectably labeled or conjugated to a toxin, a therapeutic agent, a polymer, a receptor, an enzyme, or a receptor ligand, preferably wherein the polymer is polyethylene glycol (PEG).

[0021] In some embodiments, the present disclosure provides a polynucleotide encoding the antibody or antigen-binding fragment described herein. In some embodiments, the present disclosure provides a vector comprising a polynucleotide described herein. In some embodiments, the present disclosure provides a cultured host cell comprising a vector described herein.

[0022] In some embodiments, the present disclosure provides a pharmaceutical composition comprising an antibody or antigen-binding fragment thereof, a polynucleotide, or a vector described herein.

[0023] In some embodiments, the present disclosure provides a pharmaceutical composition comprising two or more of antibodies or antigen binding fragments thereof, wherein the two or more antibodies or antigen binding fragments thereof are selected from: an antibody or antigenbinding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 9, a HCDR2 comprising an amino acid sequence of SEQ ID No: 10, a HCDR3 comprising an amino acid sequence of SEQ ID No: 11, a LCDR1 comprising an amino acid sequence of SEQ ID No: 21, a LCDR2 comprising an amino acid sequence of SEQ ID No: 22, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 23; an antibody or antigenbinding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 12, a HCDR2 comprising an amino acid sequence of SEQ ID No: 13, a HCDR3 comprising an amino acid sequence of SEQ ID No: 14, a LCDR1 comprising an amino acid sequence of SEQ ID No: 24, a LCDR2 comprising an amino acid sequence of SEQ ID No: 25, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 26; an antibody or antigenbinding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 15, a HCDR2 comprising an amino acid sequence of SEQ ID No: 16, a HCDR3 comprising an amino acid sequence of SEQ ID No: 17, a LCDR1 comprising an amino acid sequence of SEQ ID No: 27, a LCDR2 comprising an amino acid sequence of SEQ ID No: 28, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 29; an antibody or antigenbinding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 18, a HCDR2 comprising an amino acid sequence of SEQ ID No: 19, a HCDR3 comprising an amino acid sequence of SEQ ID No: 20, a LCDR1 comprising an amino acid sequence of SEQ ID No: 30, a LCDR2 comprising an amino acid sequence of SEQ ID No: 31, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 32; an antibody or antigenbinding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 44, a HCDR2 comprising an amino acid sequence of SEQ ID No: 45, a HCDR3 comprising an amino acid sequence of SEQ ID No: 46, a LCDR1 comprising an amino acid sequence of SEQ ID No: 47, a LCDR2 comprising an amino acid sequence of SEQ ID No: 48, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 49; Bebtelovimab; the P2G3 antibody; and a combination thereof. In some embodiments, one of the two or more antibodies or antigen binding fragments thereof is an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 9, a HCDR2 comprising an amino acid sequence of SEQ ID No: 10, a HCDR3 comprising an amino acid sequence of SEQ ID No: 11, a LCDR1 comprising an amino acid sequence of SEQ ID No: 21, a LCDR2 comprising an amino acid sequence of SEQ ID No: 22, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 23.

[0024] In some embodiments, the two or more antibodies or antigen binding fragments thereof are selected from an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 1, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 5; an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 2, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 6; an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 3, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 7; an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 4, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 8; an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 42, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 43; Bebtelovimab; the P2G3 antibody; and a combination thereof. In some embodiments, one of the two or more antibodies or antigen binding fragments thereof is an antibody or antigen-binding fragment thereof comprising a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 1, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 5.

[0025] In some embodiments, the pharmaceutical composition further comprises a pharmaceutical acceptable carrier.

[0026] In some embodiments, the present disclosure provides a pharmaceutical composition for use in treating a SARS-CoV-2 infection in a subject.

[0027] In some embodiments, the present disclosure provides a method of treating a SARS- CoV-2 infection in a subject, comprising administering to the subject therapeutically effective amount of an antibody or antigen-binding fragment thereof described herein or a therapeutically effective amount of a pharmaceutical composition comprising the same.

[0028] In some embodiments, the present disclosure provides a method of neutralizing SARS- CoV-2 in a subject, comprising administering to a subject in need thereof a therapeutically effective amount of the antibody or antigen -binding fragment thereof of any one of claims 1- 28 or a therapeutically effective amount of the pharmaceutical composition of any one of claims 32-35.

[0029] In some embodiments, the present disclosure provides a method of preventing a SARS- CoV-2 infection in a subject, comprising administering to a subject in need thereof a therapeutically effective amount of an antibody or antigen-binding fragment thereof described herein or a therapeutically effective amount of a pharmaceutical composition comprising the same. In some embodiments, the subject is immunocompromised.

[0030] In some embodiments, the method further comprises administering a second therapeutic agent, preferably wherein the second therapeutic agent comprises an anti-inflammatory drug or an antiviral compound. In some embodiments, (a) the antiviral compound comprises: a nucleoside analog, a peptoid, an oligopeptide, a polypeptide, a protease inhibitor, a 3C-like protease inhibitor, a papain-like protease inhibitor, or an inhibitor of an RNA dependent RNA polymerase; or (b) the antiviral compound is selected from: acyclovir, gancyclovir, vidarabine, foscamet, cidofovir, amantadine, ribavirin, trifluorothymidine, zidovudine, didanosine, zalcitabine, and an interferon, and preferably wherein the interferon is an interferon-a or an interferon-p. In some embodiments, the second therapeutic agent is administered before, after, or concurrently with the antibody or pharmaceutical composition thereof. [0031] In some embodiments, the pharmaceutical composition is administered to the subject after the exposure to SARS-CoV-2.

[0032] In some embodiments, the present disclosure provides a kit for detecting a SARS-CoV- 2 infection in a subject, comprising the antibody or antigen-binding fragment described herein. [0033] In some embodiments, the present disclosure provides a method of detecting the presence of a SARS-CoV-2 in a sample, comprising (1) contacting the sample with the antibody or antigen-binding fragment thereof described herein, and (2) detecting the presence of an antibody-antigen complex, wherein the presence of the antibody-antigen complex indicates the presence of SARS-CoV-2. In some embodiments, the antibody or antigen-binding fragment thereof is conjugated to a label, preferably wherein the label is selected from a fluorescent label, a chemiluminescent label, a radiolabel, and an enzyme. In some embodiments, the method further comprises contacting a secondary antibody with the antibody or antigen-binding fragment thereof, wherein the secondary antibody comprises a label. In some embodiments, the method further comprises detecting fluorescence or chemiluminescence of the label, preferably wherein the step of detecting comprises a competitive binding assay or ELISA. In some embodiments, the method further comprises binding the sample to a solid support, preferably wherein the solid support is selected from microparticles, microbeads, magnetic beads, and an affinity purification column.

[0034] In some embodiments, the sample is a blood sample, a nasal swab, or a throat swab.

[0035] In some embodiments, the present disclosure provides a method of preparing a antibody, or antigen-binding fragment thereof, comprising: obtaining a cultured host cell; culturing the cultured host cell in a medium under conditions permitting expression of a polypeptide encoded by the vector and assembling of an antibody or fragment thereof; and purifying the antibody or fragment from the cultured cell or the medium of the cell.

[0036] In some embodiments, the present disclosure provides a kit comprising a pharmaceutically acceptable dose unit of the antibody or antigen-binding fragment thereof described herein or a pharmaceutical composition comprising the same.

[0037] In some embodiments, the present disclosure provides a kit for the diagnosis, prognosis or monitoring treatment of SARS-CoV-2 in a subject, comprising: the antibody or antigenbinding fragment thereof described herein; and at least one detection reagent that binds specifically to the antibody or antigen-binding fragment thereof.

[0038] In some embodiments, the present disclosure provides a method of neutralizing SARS- CoV-2 in a subject, comprising administering to a subject in need thereof a therapeutically effective amount of two or more monoclonal antibodies or antigen-binding fragments thereof described herein. In some embodiments, the present disclosure provides a method of treating a SARS-CoV-2 in a subject in need thereof, comprising administering to a subject in need thereof a therapeutically effective amount of two or more monoclonal antibodies or antigen-binding fragments thereof described herein. In some embodiments, the present disclosure provides a method of preventing a SARS-CoV-2 in a subject in need thereof, comprising administering to a subject in need thereof a therapeutically effective amount of two or more monoclonal antibodies or antigen-binding fragments thereof described herein.

[0039] In some embodiments, the two or more antibodies or antigen-binding fragments thereof are selected from: an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 9, a HCDR2 comprising an amino acid sequence of SEQ ID No: 10, a HCDR3 comprising an amino acid sequence of SEQ ID No: 11, a LCDR1 comprising an amino acid sequence of SEQ ID No: 21, a LCDR2 comprising an amino acid sequence of SEQ ID No: 22, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 23; an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 12, a HCDR2 comprising an amino acid sequence of SEQ ID No: 13, a HCDR3 comprising an amino acid sequence of SEQ ID No: 14, a LCDR1 comprising an amino acid sequence of SEQ ID No: 24, a LCDR2 comprising an amino acid sequence of SEQ ID No: 25, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 26; an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 15, a HCDR2 comprising an amino acid sequence of SEQ ID No: 16, a HCDR3 comprising an amino acid sequence of SEQ ID No: 17, a LCDR1 comprising an amino acid sequence of SEQ ID No: 27, a LCDR2 comprising an amino acid sequence of SEQ ID No: 28, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 29; an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 18, a HCDR2 comprising an amino acid sequence of SEQ ID No: 19, a HCDR3 comprising an amino acid sequence of SEQ ID No: 20, a LCDR1 comprising an amino acid sequence of SEQ ID No: 30, a LCDR2 comprising an amino acid sequence of SEQ ID No: 31, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 32; an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 44, a HCDR2 comprising an amino acid sequence of SEQ ID No: 45, a HCDR3 comprising an amino acid sequence of SEQ ID No: 46, a LCDR1 comprising an amino acid sequence of SEQ ID No: 47, a LCDR2 comprising an amino acid sequence of SEQ ID No: 48, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 49; Bebtelovimab; the P2G3 antibody; and a combination thereof. In some embodiments, one of the two or more antibodies or antigen binding fragments thereof is an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 9, a HCDR2 comprising an amino acid sequence of SEQ ID No: 10, a HCDR3 comprising an amino acid sequence of SEQ ID No: 11, a LCDR1 comprising an amino acid sequence of SEQ ID No: 21, a LCDR2 comprising an amino acid sequence of SEQ ID No: 22, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 23.

[0040] In some embodiments, the two or more monoclonal antibodies or antigen binding fragments thereof are selected from: an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 1, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 5; an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 2, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 6; an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 3, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 7; an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 4, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 8; an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 42, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 43; Bebtelovimab; the P2G3 antibody; and a combination thereof. In some embodiments, one of the two or more antibodies or antigen binding fragments thereof is an antibody or antigen-binding fragment thereof comprising a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 1, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 5.

[0041] In some embodiments, the first antibody or antigen-binding fragment thereof and the second antibody or antigen binding fragment thereof exhibit synergistic activity.

[0042] In some embodiments, the method further comprises administering to the subject a therapeutically effective amount of a second therapeutic agent or therapy. In some embodiments, the second therapeutic agent comprises an anti-inflammatory drug or an antiviral compound. In some embodiments, (a) the antiviral compound comprises: a nucleoside analog, a peptoid, an oligopeptide, a polypeptide, a protease inhibitor, a 3C-like protease inhibitor, a papain-like protease inhibitor, or an inhibitor of an RNA dependent RNA polymerase; or (b) the antiviral compound is selected from: acyclovir, gancyclovir, vidarabine, foscarnet, cidofovir, amantadine, ribavirin, trifluorothymidine, zidovudine, didanosine, zalcitabine, and an interferon, and preferably wherein the interferon is an interferon-a or an interferon-p.

[0043] In some embodiments, the first antibody or antigen-binding fragment thereof is administered before, after, or concurrently with the second antibody or antigen-binding fragment thereof. In some embodiments, the antibody or antigen-binding fragment thereof is administered to the subject intravenously, subcutaneously, or intraperitoneally.

BRIEF DESCRIPTION OF THE FIGURES

[0044] Figs. 1A-1H shows anti-SARS-CoV-2 neutralizing antibody binding to Spike trimer proteins in Luminex biochemical assay.

[0045] Figs. 2A-2H shows anti-SARS-CoV-2 neutralizing antibody activity in blocking the Spike-ACE2 interaction in Luminex biochemical assay.

[0046] Figs. 3A-3D shows antibody neutralizing activity in the SARS-CoV-2 Spike pseudotyped lentiviral assay.

[0047] Figs. 4A-4C shows antibody neutralizing activity in the live virus SARS-CoV-2 cytopathic effect assay.

[0048] Figs. 5A-5C shows cryo electron microscopy structural studies of the Red-E2 Fab bound to the Omicron BA.1 Spike trimer.

[0049] Figs. 6A-6C shows cryo electron microscopy structural studies of the P4J15 Fab bound to the Omicron XBB Spike trimer.

[0050] Figs. 7A-7B shows cryo electron microscopy structural model of (A) labelled P4J15 Fab residues contacting the receptor binding domain (RBD) of the Omicron XBB Spike trimer and (B) labelled RBD residues contacting P4J15 Fab.

[0051] Fig. 8 shows a top view of the P4J 15 residues contacting RBD and P4J 15 contact buried surface on the RBD.

[0052] Figs. 9A-9B shows an overview of the procedure for the selection of viral escape mutations to P4J15 and mutations selected starting with Omicron BA.2.75.2 and BQ. l viruses. [0053] Figs. 10A-10B shows P4J15 antibody neutralizing activity against Spike escape mutations in the virus-like particle cell-based neutralization assay.

[0054] Figs. 11A-11D shows the relative infectivity and ACE2 binding affinity of the Spike mutations selected in the P4J15 viral resistance studies. [0055] Fig. 12 shows neutralizing activity of P4J15 compared to Evusheld and Bebtelovimab in lentivirus pseudo-typed and virus-like particle cell-based assays, both using Spike from a panel of SARS-CoV-2 variants of concern.

[0056] Figs. 13A-13B shows de-risking studies by mutational engineering of P4J15 to exchange residues that could represent potential liabilities during large scale manufacturing or could exhibit off-target binding.

[0057] Fig. 14 shows neutralizing potency of P4J15 de-risked antibodies in the Spike pseudotyped lentivirus assay produced with different SARS-CoV-2 variants of concern or point mutations at the P4J15 contact site on the RBD.

[0058] Fig. 15 shows the neutralizing activity of P4J 15-MX08 against a panel of Spike pseudotyped lentivirus assay produced with different SARS-CoV-2 variants of concern, point mutations and escape mutations at the P4J15 contact site on the RBD.

[0059] Figs. 16A-16B shows that P4J15-MX08 exhibits potent antibody dependent cellular phagocytosis (ADCP) activity in an assay performed with U937 monocytes and Spike Omicron BA.1 or XBB.1 coated fluorescent beads.

[0060] Figs. 17A-17C shows that P4J15 LS exhibits strong prophylactic protection from infection with the Omicron BA.5 SARS-CoV-2 virus in the hamster challenge model.

[0061] Fig. 18 shows that P4J 15 LS exhibits near complete prophylactic protection of monkeys challenged with the Omicron XBB.1.5 SARS-CoV-2 virus.

[0062] Fig. 19 shows results of binding studies of anti-SARS-CoV-2 neutralizing antibodies in biochemical assays.

[0063] Fig. 20 shows results of a spike-ACE2 blocking activity of anti-SARS-CoV-2 neutralizing antibodies in a biochemical assay.

[0064] Fig. 21 shows activity of antibodies in the Spike pseudoviral neutralization assay.

[0065] Fig. 22 shows activity of antibodies in neutralizing lentiviruses pseudotyped with Spike encoding mutations that confer resistance to the Class 3 antibody, Bebtelovimab.

[0066] Fig. 23 shows activity of antibodies in the live virus cytopathic effect neutralization assay.

[0067] Fig. 24 shows antibody competitive binding studies with SARS-CoV-2 RBD to define competitive, partially overlapping and non-overlapping binding epitopes between antibody pairs. Competitive interaction is defined as <25% co-binding and partially competitive is defined as 25%-70% co-binding of antibody pairs. Box with strips indicates incomplete blockade of the ACE2 interaction with Spike trimer protein from one or more of the viral variants of concern. DETAILED DESCRIPTION

[0068] SARS-CoV-2 is an enveloped virus, wherein the viral envelope is typically made up of three proteins that include the membrane protein (M), the envelope protein (E), and the spike protein (S). As compared to the M and E proteins that are primarily involved in virus assembly, the S protein plays a crucial role in penetrating host cells and initiating infection. One of the key biological characteristics of SARS-CoV-2 is the presence of spike proteins that allow these viruses to penetrate host cells through cell receptor proteins, such as angiotensin-converting enzyme 2 (ACE-2) receptor, and cause infection. The S protein is a highly glycosylated and large type I transmembrane fusion protein that is made up of 1,160 to 1,400 amino acids, depending upon the type of virus. In addition to its role in penetrating cells, the S protein of the SARS-CoV-2 virus is a major inducer of neutralizing antibodies. Coronavirus S (spike) protein is initially synthesized as a precursor protein. Individual precursor S polypeptides form a homotrimer and undergo glycosylation within the Golgi apparatus as well as processing to remove the signal peptide, and cleavage by a cellular protease to generate separate SI and S2 polypeptide chains, which remain associated as S1/S2 protomers within the homotrimer and is therefore a trimer of heterodimers. The SI subunit is distal to the virus membrane and contains the receptor-binding domain (RBD) that mediates virus attachment to its host (cell) receptor. The S2 subunit contains fusion protein machinery, such as the fusion peptide, two heptad-repeat sequences (HR1 and HR2) and a central helix typical of fusion glycoproteins, a transmembrane domain, and the cytosolic tail domain. A structural conformation adopted by the ectodomain of the coronavirus S protein following processing into a mature coronavirus S protein in the secretory system, and prior to triggering of the fusogenic event that leads to transition of coronavirus S to the postfusion conformation.

[0069] The present disclosure provides antibodies and antigen-binding fragments thereof that bind the SARS-CoV-2 Spike protein or fragment thereof (for example, the receptor binding domain (RBD), theN-terminal domain (NTD), the subdomain (SD), or the S2 domain). In some embodiments, the antibodies described herein have potent neutralizing activity against the SARS-CoV-2 virus. In some embodiments, the present disclosure provides an antibody or a combination of two or more antibodies described herein for use in prophylactic protection of individuals from SARS-CoV-2 infection and/or therapeutic agents that could ameliorate the clinical outcome of individuals already infected with the SARS-CoV-2 virus. In some embodiments, the antibodies or combinations thereof can be used in for the prophylactic protection of immunocompromised individuals for whom traditional vaccines are less effective. Definitions

[0070] Unless otherwise defined herein, technical and scientific terms used in the present description have the meanings that are commonly understood by those of ordinary skill in the art. For purposes of interpreting this specification, the following description of terms will apply and whenever appropriate, terms used in the singular will also include the plural and vice versa unless the content clearly dictates otherwise. In the event that any description of a term set forth conflicts with any document incorporated herein by reference, the description of the term set forth below shall control.

[0071] The terms “a”, “an”, and “the”, as used herein, include plural references unless the context clearly dictates otherwise.

[0072] The term “about”, as used herein, in reference to a number or range of numbers, is understood to mean the stated number and numbers +/- 10% thereof, or 10% below the lower listed limit and 10% above the higher listed limit for the values listed for a range.

[0073] The term “between”, as used in a phrase as such “between A and B” or “between A-B” refers to a range including both A and B.

[0074] The terms “or” and “and/or”, as used herein, include any, and all, combinations of one or more of the associated listed items.

[0075] The terms “including”, “includes”, “included”, and other forms, as used herein, are not limiting.

[0076] The terms “comprise” and its grammatical equivalents, as used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

[0077] The term “administer”, “administration”, or “administering”, as used herein refers to the act of injecting or otherwise physically delivering a substance (e.g., a pharmaceutical composition provided herein) to a subject, such as by oral, mucosal, topical, intradermal, parenteral, intravenous, intravitreal, intraarticular, subretinal, intramuscular, intrathecal delivery and/or any other method of physical delivery described herein or known in the art. The delivery can be systemic or to a specific tissue.

[0078] The term “antibody,” “immunoglobulin,” or “Ig” is used interchangeably herein, and is used in the broadest sense and specifically covers, for example, monoclonal antibodies (including agonist, antagonist, neutralizing antibodies, full length or intact monoclonal antibodies), antibody compositions with polyepitopic or monoepitopic specificity, polyclonal or monovalent antibodies, multivalent antibodies, and multispecific antibodies (e.g., bispecific antibodies so long as they exhibit the desired biological activity). A conventional antibody is composed of two identical pairs of polypeptide chains, wherein each pair has one heavy chain (about 50-70 kDa) and one light chain (about 25 kDa), each amino-terminal portion of each chain includes a variable region of about 100 to about 130 or more amino acids, and each carboxy -terminal portion of each chain includes a constant region. See, e.g., Antibody Engineering (Borrebaeck, ed., 2d ed. 1995); and Kuby, Immunology (3d ed. 1997). An antibody can be human, humanized, chimeric and/or affinity matured, as well as an antibody from other species, for example, mouse and rabbit, etc. Antibodies also include, but are not limited to, synthetic antibodies, recombinantly produced antibodies, camelized antibodies or their humanized variants, and intrabodies. An antibody can be selected from any class of immunoglobulins, including IgM, IgG, IgD, IgA and IgE, and any isotype, including IgGl, IgG2, IgG3 and IgG4 (e.g., variants of IgG4 and IgG4 nullbody). An antibody can comprise kappa or lambda light chain constant sequences.

[0079] The term “antibody fragment” refers to a molecule other than an intact antibody that comprises a portion of an intact antibody that binds the antigen to which the intact antibody binds. Examples of antibody fragments include but are not limited to Fv, Fab, Fab', Fab'-SH, F(ab')2; diabodies; linear antibodies; single-chain antibody molecules e.g., scFv); and multispecific antibodies formed from antibody fragments.

[0080] The term “antigen” refers to a molecule or a portion of a molecule capable of being bound by an antibody or an antigen-binding fragment thereof and additionally capable of being used in an animal to produce antibodies capable of binding to an epitope of that antigen. An antigen may be a polypeptide, carbohydrate, nucleic acid, lipid, hapten, or other naturally occurring or synthetic compound.

[0081] The term “antibody” refers to an immunoglobulin, antigen-binding fragment, or variant thereof, that binds and recognizes a SARS-CoV-2 Spike protein and/or an epitope on the RBD, an antigenic fragment thereof, or a dimer or multimer of the antigen. These antibodies can be used alone, or in combination, as prophylactic or therapeutic agents upon appropriate formulation, in association with active vaccination, as a diagnostic tool, or as a production tool as described herein.

[0082] The term “binds” or “binding”, as used herein, refers to a covalent or non-covalent interaction between molecules (e.g., forming a complex by interactions). Exemplary non- covalent interactions include hydrogen bonds, ionic bonds, hydrophobic interactions, and/or van der Waals interactions. As used herein, the term “specifically binds” refers to binding of an antibody or an antigen binding fragment thereof to an antigen with a dissociation constant (KD) <10^-7 M. The term “KD” is intended to refer to the dissociation equilibrium constant of a particular antibody-antigen interaction. The ratio of dissociation rate (k_Off) to association rate (k_on) of an antibody to a monovalent antigen (k_off/k_on) is the dissociation constant KD, which is inversely related to affinity. The lower the KD value, the higher the affinity of the antibody. The value of KD varies for different complexes of antibody and antigen and depends on both k_onand k_Off. The dissociation constant KD for an antibody provided herein can be determined using any method provided herein or any other method well known to those skilled in the art. Specific binding can be measured, for example, by determining binding of a molecule compared to binding of a control molecule, which generally is a molecule of similar structure that does not have binding activity.

[0083] The term “binding affinity”, as used herein, refers to the strength of the sum total of noncovalent interactions between a single binding site of a molecule (e.g., a binding protein such as an antibody) and its binding partner (e.g., an antigen). Unless indicated otherwise, as used herein, “binding affinity” refers to intrinsic binding affinity which reflects a 1 : 1 interaction between members of a binding pair (e.g., antibody and antigen). The affinity of a binding molecule X for its binding partner Y can generally be represented by the dissociation constant (KD). Low-affinity antibodies generally bind antigen slowly and tend to dissociate readily, whereas high-affinity antibodies generally bind antigen faster and tend to remain bound longer. A variety of methods of measuring binding affinity are known in the art, any of which can be used for purposes of the present disclosure.

[0084] The term “coding sequence” or a polynucleotide which “encodes” a polypeptide, as used herein, is a nucleic acid molecule which is transcribed (in the case of DNA) and translated (in the case of mRNA) into a polypeptide when placed under the control of appropriate regulatory sequences. The boundaries of the coding sequence are determined by a start codon at the 5’ (amino) terminus and a translation stop codon at the 3’ (carboxy) terminus. A transcription termination sequence may be located 3’ to the coding sequence.

[0085] The term “constant region” or “constant domain”, as used herein, refers to a carboxy terminal portion of the light and heavy chain which is not directly involved in binding of the antibody to antigen but exhibits various effector function, such as interaction with the Fc receptor. This portion has a conserved amino acid sequence relative to the variable region. The constant region may contain the CHI, CH2, and CH3 regions of the heavy chain and the CL region of the light chain.

[0086] The term “effective amount”, as used herein, refers to an amount of a therapeutic (e.g., a pharmaceutical composition provided herein) which is sufficient to prevent, diagnose, treat, delay the onset of, reduce and/or ameliorate the severity, duration, advancement, and/or recurrence of a given condition, disorder or disease and/or a symptom related thereto. The term also encompasses an amount necessary to improve or enhance the prophylactic or therapeutic effect (s) of another therapy or to serve as a bridge to another therapy. A “therapeutically effective amount” is at least the minimum concentration required to effect a measurable improvement of a particular disorder (e.g., SARS-CoV-2 infection). A therapeutically effective amount herein may vary according to factors such as the disease state, age, sex, and weight of the patient, and the ability of the antibody to elicit a desired response in the individual. A therapeutically effective amount is also one in which any toxic or detrimental effects of the antibody are outweighed by the therapeutically beneficial effects. A “prophylactically effective amount” refers to an amount effective, at the dosages and for periods of time necessary, to achieve the desired prophylactic result. Typically, but not necessarily, since a prophylactic dose is used in subjects prior to or at an earlier stage of disease, a prophylactically effective amount may be less than a therapeutically effective amount.

[0087] The term “epitope”, as used herein, refers to a localized region of an antigen to which an antibody can bind. In the case of a polypeptide antigen, for example, an epitope can be contiguous amino acids of the polypeptide (a “linear” epitope) or an epitope can comprise amino acids from two or more non-contiguous regions of the polypeptide (a “conformational,” “non-linear” or “discontinuous” epitope). It will be appreciated by one of skill in the art that, in general, a linear epitope may or may not be dependent on secondary, tertiary, or quaternary structure. In some embodiments, an antibody binds to a group of amino acids regardless of whether they are folded in a natural three dimensional protein structure. In some embodiments, an antibody requires amino acid residues making up the epitope to exhibit a particular conformation (e.g., bend, twist, turn or fold) in order to recognize and bind the epitope.

[0088] The term “Fab” or “Fab region”, as used herein, refers to an antibody region that binds to antigens. A conventional IgG usually comprises two Fab regions, each residing on one of the two arms of the Y-shaped IgG structure. Each Fab region is typically composed of one variable region and one constant region of each of the heavy and the light chain. More specifically, the variable region and the constant region of the heavy chain in a Fab region are VH and CHI regions, and the variable region and the constant region of the light chain in a Fab region are VL and CL regions. The VH, CHI, VL, and CL in a Fab region can be arranged in various ways to confer an antigen binding capability. For example, VH and CHI regions can be on one polypeptide, and VL and CL regions can be on a separate polypeptide, similarly to a Fab region of a conventional IgG. Alternatively, VH, CHI, VL and CL regions can all be on the same polypeptide and oriented in different orders.

[0089] The term “Fc region”, as used herein, refers to a C-terminal region of an immunoglobulin heavy chain, including, for example, native sequence Fc regions, recombinant Fc regions, and variant Fc regions. Although the boundaries of the Fc region of an immunoglobulin heavy chain might vary, the human IgG heavy chain Fc region is often defined to stretch from an amino acid residue at position Cys226, or from Pro230, to the carboxylterminus thereof. The C-terminal lysine (residue 447 according to the EU numbering system) of the Fc region may be removed, for example, during production or purification of the antibody, or by recombinantly engineering the nucleic acid encoding a heavy chain of the antibody. Accordingly, a composition of intact antibodies may comprise antibody populations with all K447 residues removed, antibody populations with no K447 residues removed, and antibody populations having a mixture of antibodies with and without the K447 residue. A “functional Fc region” possesses an “effector function” of a native sequence Fc region. Exemplary “effector functions” include Clq binding; CDC; Fc receptor binding; ADCC; phagocytosis; downregulation of cell surface receptors (e.g., B cell receptor), etc. Such effector functions generally require the Fc region to be combined with a binding region or binding domain (e.g., an antibody variable region or domain) and can be assessed using various assays known to those skilled in the art.

[0090] The term “fragment”, as used herein, refers to a portion of a polypeptide or polynucleotide molecule containing less than the entire polypeptide or polynucleotide sequence. In some embodiments, a fragment of a polypeptide or polynucleotide comprises at least about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, about 95%, about 96%, about 97%, about 98%, or about 99% of the entire length of the reference polypeptide or polynucleotide. In some embodiments, a fragment of a polypeptide or polynucleotide comprises about 10%-99%, about 20%-99%, about 30%-99%, about 40%-99%, about 50%-99%, about 60%-99%, about 70%-99%, about 80%-99%, about 90%-99%, about 95%-99%, about 96%-99%, about 97%-99%, or about 98%-99%, of the entire length of the reference polypeptide or polynucleotide. In some embodiments, a polypeptide or polynucleotide fragment may contain about 5, about 10, about 15, about 20, about 25, about 30, about 35, about 40, about 45, about 50, about 60, about 70, about 80, about 90, about 100, about 200, about 300, about 400, about 500, about 600, about 700, about 800, about 900, about 1000, or more nucleotides or amino acids. [0091] The term “heavy chain”, when used in reference to an antibody, refers to a polypeptide chain of about 50-70 kDa, wherein the amino-terminal portion includes a variable region of about 120 to 130 or more amino acids, and a carboxy -terminal portion includes a constant region. The constant region can be one of five distinct types, (e.g, isotypes) referred to as alpha, delta, epsilon, gamma, and mu, based on the amino acid sequence of the heavy chain constant region. The distinct heavy chains differ in size: alpha, delta, and gamma contain approximately 450 amino acids, while epsilon and mu contain approximately 550 amino acids. When combined with a light chain, these distinct types of heavy chains give rise to five well known classes (e.g., isotypes) of antibodies, IgA, IgD, IgE, IgG, and IgM, respectively, including four subclasses of IgG, namely IgGl, IgG2, IgG3, and IgG4.

[0092] The term “host”, as used herein, refers to an animal, such as a mammal (e.g., a human). [0093] The term “host cell”, as used herein, refers to a particular subject cell into which an exogenous nucleic acid molecule may be introduced and the progeny or potential progeny of such a cell. Progeny of such a cell may not be identical to the parent cell comprising the nucleic acid molecule due to mutations or environmental influences that may occur in succeeding generations or integration of the nucleic acid molecule into the host cell genome.

[0094] The term “isolated nucleic acid” or “isolated polynucleotide”, as used herein, refers to a nucleic acid, for example, an RNA, DNA, or a mixed nucleic acids, substantially separated from other genomic DNA sequences as well as proteins or complexes such as ribosomes and polymerases that naturally accompany a native sequence, or culture medium when produced by recombinant techniques, or chemical precursors or other chemicals when chemically synthesized.

[0095] The term “light chain”, when used in reference to an antibody, refers to a polypeptide chain of about 25 kDa, wherein the amino-terminal portion includes a variable region of about 100 to about 110 or more amino acids, and a carboxy -terminal portion includes a constant region. The approximate length of a light chain is 211 to 217 amino acids. There are two distinct types, referred to as kappa or lambda based on the amino acid sequence of the constant domains. [0096] The term “monoclonal antibody,” as used herein, refers to an antibody obtained from a population of substantially homogeneous antibodies, e.g., the individual antibodies comprising the population are identical except for possible naturally occurring mutations that may be present in minor amounts, and each monoclonal antibody will typically recognize a single epitope on the antigen.

[0097] The term “neutralize,” when used in relation to an antibody, refers to the antibody’s ability to block the corresponding antigen’s function by binding to the antigen. A “neutralizing antibody” is one that can neutralize, i.e., prevent, inhibit, reduce, impede or interfere with, the ability of a pathogen to initiate and/or perpetuate an infection in a host.

[0098] The term “operatively linked” and similar phrases (e.g., operably linked, genetically fused), as used herein, refer to the operational linkage of nucleic acid sequences or amino acid sequences placed in functional relationships with each other. For example, a promoter operatively linked to a polynucleotide encoding a polypeptide result in the transcription of the polynucleotide and ultimately the expression of the polypeptide. As another example, an operatively linked peptide is one in which the functional domains are placed with appropriate distance from each other to impart the intended function of each domain.

[0099] The term “pharmaceutically acceptable excipient, carrier or diluent”, as used herein, refers to any substance formulated alongside the active ingredient of a pharmaceutical composition that allows the active ingredient to retain biological activity and is non-reactive with the subject’s immune system. Such a substance can be included for the purpose of longterm stabilization, bulking up solid formulations that contain potent active ingredients in small amounts, or to confer a therapeutic enhancement on the active ingredient in the final dosage form, such as facilitating absorption, reducing viscosity, or enhancing solubility. The selection of appropriate substance can depend upon the route of administration and the dosage form, as well as the active ingredient and other factors. Compositions having such substances can be formulated by well-known conventional methods (see, e.g., Remington, The Science and Practice of Pharmacy, 23rd edition, A. Adejare, ed., Academic Press, 2020).

[0100] The term “pharmaceutical composition” or “therapeutic composition”, as used here, refers to a composition capable of being administered to a subject for the treatment of a particular disease or disorder.

[0101] The term “polynucleotide” or “nucleic acid”, as used herein, refers to deoxyribonucleic acid (DNA), ribonucleic acid (RNA) and DNA/RNA hybrids. Polynucleotides may be singlestranded or double-stranded and either recombinant, synthetic, or isolated. Polynucleotides include, but are not limited to: pre-messenger RNA (pre-mRNA), messenger RNA (mRNA), RNA, genomic DNA (gDNA), PCR amplified DNA, complementary DNA (cDNA), synthetic DNA, or recombinant DNA. Polynucleotides can comprises modified nucleotides or bases, and/or their analogs, or any substrate that can be incorporated into a polymer by DNA or RNA polymerase or by a synthetic reaction. Unless specified otherwise, the left-hand end of any single-stranded polynucleotide sequence disclosed herein is the 5’ end; the left-hand direction of double-stranded polynucleotide sequences is referred to as the 5’ direction. The direction of 5’ to 3’ addition of nascent RNA transcripts is referred to as the transcription direction. [0102] The terms “polypeptide” and “peptide” and “protein”, as used herein, refer to polymers of amino acids of any length. The polymer may be linear or branched, it may comprise modified amino acids, and it may be interrupted by non-amino acids. The terms also encompass an amino acid polymer that has been modified naturally or by intervention; for example, disulfide bond formation, glycosylation, lipidation, acetylation, phosphorylation, or any other manipulation or modification. Also included within the definition are, for example, polypeptides containing one or more analogs of an amino acid, including but not limited to, unnatural amino acids, as well as other modifications known in the art.

[0103] The term “prevent”, as used herein, refers to a pharmaceutical or other intervention regimen for reducing the likelihood of the onset (or recurrence) of a disease, disorder, condition, or associated symptom(s). Preventing includes delaying, preventing, or eliminating the appearance of a disease or condition, delaying, or eliminating the onset of symptoms of a disease or condition, slowing, halting, or reversing the progression of a disease or condition, or any combination thereof.

[0104] The term “sequence identity”, as used herein, refers to the percentage of bases or amino acids between two polynucleotide or polypeptide sequences that are the same, and in the same relative position. As such one polynucleotide or polypeptide sequence has a certain percentage of sequence identity compared to another polynucleotide or polypeptide sequence. For sequence comparison, typically one sequence acts as a reference sequence, to which test sequences are compared. The term “reference sequence” refers to a molecule to which a test sequence is compared. Methods of sequence alignment for comparison and determination of percent sequence identity and percent complementarity are well known in the art. Optimal alignment of sequences for comparison can be conducted, e.g., by the homology alignment algorithm of Needleman and Wunsch, (1970) J. Mol. Biol. 48:443, by the search for similarity method of Pearson and Lipman, (1988) Proc. Nat’l. Acad. Sci. USA 85:2444, by computerized implementations of these algorithms (GAP, BESTFIT, FASTA, and TFASTA in the Wisconsin Genetics Software Package, Genetics Computer Group, 575 Science Dr., Madison, WI), by manual alignment and visual inspection (see, e.g., Brent et al., (2003) Current Protocols in Molecular Biology), by use of algorithms know in the art including the BLAST and BLAST 2.0 algorithms, which are described in Altschul et al., (1977) Nuc. Acids Res. 25:3389-3402; and Altschul et al., (1990) J. Mol. Biol. 215:403-410, respectively. Software for performing BLAST analyses is publicly available through the National Center for Biotechnology Information. BLAST nucleotide searches can be performed with the NBLAST nucleotide program parameters set, e.g., for score 100, word length-2 to obtain nucleotide sequences homologous to a nucleic acid molecule described herein. BLAST protein searches can be performed with the XBLAST program parameters set, e.g., to score 50, word length-3 to obtain amino acid sequences homologous to a protein molecule described herein. To obtain gapped alignments for comparison purposes, Gapped BLAST can be utilized as described in Altschul et al., Nucleic Acids Res., 1997, 25:3389-402. Alternatively, PSI BLAST can be used to perform an iterated search which detects distant relationships between molecules (Id.). When utilizing BLAST, Gapped BLAST, and PSI BLAST programs, the default parameters of the respective programs (e.g., of XBLAST and NBLAST) can be used (see, e.g., National Center for Biotechnology Information (NCBI) on the worldwide web, ncbi.nlm.nih.gov). Another nonlimiting example of a mathematical algorithm utilized for the comparison of sequences is the algorithm of Myers and Miller, 1988, CAB IOS 4: 11 17. Such an algorithm is incorporated in the ALIGN program (version 2.0) which is part of the GCG sequence alignment software package. When utilizing the ALIGN program for comparing amino acid sequences, a PAM 120 weight residue table, a gap length penalty of 12, and a gap penalty of 4 can be used.

[0105] The term “subject”, as used herein, refers to an “animal” and in particular a “mammal” such as a non-primate (e.g., mice, rats, bovines, horses, household cats, tigers and other large cats, dogs, pigs, rabbits, goats, deer, sheep, ferrets, gerbils, guinea pigs, hamsters, bats, and birds e.g., chickens, turkeys, and ducks)) or a primate (e.g., monkeys, baboons, chimpanzees, and human). The term may be used interchangeably with the term “patient” or “individual”. In some embodiments, the subject is a mammal, e.g., a human, diagnosed with a disease or disorder provided herein. In some embodiments, the subject is a mammal, e.g., a human, at risk of developing a disease or disorder provided herein. In some embodiments, the subject is human. The term does not denote a particular age or sex. Thus, individuals of all ages, from newborn to adult, whether male or female, are intended to be covered.

[0106] The term “treatment” (and grammatical variations thereof such as “treat” or “treating”) refers to clinical intervention designed to alter the natural course of the individual or cell being treated during the course of clinical pathology. Desirable effects of treatment include, but are not limited to, alleviation of symptoms, diminishment of any direct or indirect pathological consequences of the disease, decreasing the rate of disease progression, amelioration or palliation of the disease state, and remission or improved prognosis. Treating may refer to eradication or amelioration of symptoms or of an underlying disorder being treated. Treating may also be achieved with the eradication or amelioration of one or more of the physiological symptoms associated with the underlying disorder such that an improvement is observed in the subject, notwithstanding that the subject may still be afflicted with the underlying disorder. In some embodiments, antibodies of the present disclosure are used to delay development of a disease or to slow the progression of a disease. In some embodiments, the disease is a SARS- CoV-2-associated disease. In some embodiments, the SARS-CoV-2-associated disease is SARS-CoV-2 infection. An individual is successfully “treated”, for example, if one or more symptoms associated with SARS-CoV-2 infection are mitigated or eliminated.

[0107] The term “variable region”, “variable domain”, “V region”, or “V domain”, as used herein, refers to a portion of the light or heavy chains of an antibody that is generally located at the amino-terminal of the light or heavy chain and has a length of about 120 to 130 amino acids in the heavy chain and about 100 to 110 amino acids in the light chain, and are used in the binding and specificity of each particular antibody for its particular antigen. The variable region of the heavy chain may be referred to as “VH.” The variable region of the light chain may be referred to as “VL.” The term “variable” refers to the fact that certain segments of the variable regions differ extensively in sequence among antibodies. The V region mediates antigen binding and defines specificity of a particular antibody for its particular antigen. However, the variability is not evenly distributed across the 110-amino acid span of the variable regions. Instead, the V regions consist of less variable (e.g., relatively invariant) stretches called framework regions (FRs) of about 15-30 amino acids separated by shorter regions of greater variability (e.g., extreme variability) called “hypervariable regions” or “complementarity determining regions” that are each about 9-12 amino acids long. The variable regions of heavy and light chains each comprise four FRs, largely adopting a P sheet configuration, connected by three hypervariable regions, which form loops connecting, and in some cases form part of, the P sheet structure. The hypervariable regions in each chain are held together in close proximity by the FRs and, with the hypervariable regions from the other chain, contribute to the formation of the antigen-binding site of antibodies (see, e.g., Kabat et al, Sequences of Proteins of Immunological Interest (5th ed. 1991)).

[0108] The complementarity determining regions (CDRs) have been defined by well-known numbering systems. For example, the Kabat Complementarity Determining Regions (CDRs) are based on sequence variability and are the most commonly used (see, e.g., Kabat, et al., supra). Chothia refers instead to the location of the structural loops (see, e.g., Chothia and Lesk, J. Mol. Biol., 1987, 196:901-17). The end of the Chothia CDR-H1 loop when numbered using the Kabat numbering convention varies between H32 and H34 depending on the length of the loop (this is because the Kabat numbering scheme places insertions at H35A and H35B; if neither 35A nor 35B is present, the loop ends at 32; if only 35A is present, the loop ends at 33; if both 35 A and 35B are present, the loop ends at 34). The AbM hypervariable regions represent a compromise between the Kabat CDRs and Chothia structural loops, and are used by Oxford Molecular’s AbM antibody modeling software (see, e.g., Antibody Engineering Vol. 2 (Rontermann and Diibel, eds., 2d ed. 2010)). The “contact” CDRs are based on an analysis of the available complex crystal structures. Another universal numbering system that has been developed and widely adopted is ImMunoGeneTics (IMGT) Information System® (Lafranc, et al, Dev. Comp. Immunol., 2003, 27(l):55-77). IMGT is an integrated information system specializing in immunoglobulins (IG), T-cell receptors (TCR), and major histocompatibility complex (MHC) of human and other vertebrates. An additional numbering system (AHon) has been developed by Honegger and Pluckthun, J. Mol. Biol., 2001, 309: 657-70. Correspondence between the numbering system, including, for example, the Kabat numbering and the IMGT unique numbering system, is well known to one skilled in the art (see, e.g., Kabat, supra, Chothia and Lesk, supra; Martin, supra, Lefranc, et al., supra). The boundaries of a given CDR may vary depending on the scheme used for identification. Thus, unless otherwise specified, the CDRs of a given antibody or region thereof, such as a variable region, should be understood to encompass the complementary determining region as defined by any of the known schemes described herein. In some instances, the scheme for identification of a particular CDR or CDRs is specified, such as the CDR as defined by the Kabat, Chothia, or Contact method. In other cases, the particular amino acid sequence of a CDR is given. As the “location” of the CDRs within the structure of the immunoglobulin variable domain is conserved between species and present in structures called loops, by using numbering systems that align variable domain sequences according to structural features, CDR and framework residues are readily identified. This information can be used in grafting and replacement of CDR residues from immunoglobulins of one species into an acceptor framework from, typically, a human antibody. [0109] The term “variant”, when used in relation to polypeptide, refers to a polypeptide comprising one or more (such as, for example, about 1 to about 25, about 1 to about 20, about 1 to about 15, about 1 to about 10, or about 1 to about 5) amino acid sequence substitutions, deletions, and/or additions as compared to a native or unmodified sequence. Variants may be naturally occurring, such as allelic or splice variants, or may be artificially constructed. Polypeptide variants may be prepared from the corresponding nucleic acid molecules encoding the variants.

[0110] The term “vector”, as used herein, refers to a substance that is used to carry or introduce a nucleic acid sequence (e.g., a nucleic acid sequence encoding an antibody as described herein) into a host cell. Vectors applicable for use include, for example, plasmids, phage vectors, viral vectors, episomes, and artificial chromosomes. A vector may include sequences that direct autonomous replication in a cell, or may include sequences sufficient to allow integration into host cell DNA. Additionally, the vectors can include one or more selectable marker genes and appropriate expression control sequences. Selectable marker genes that can be included, for example, provide resistance to antibiotics or toxins, complement auxotrophic deficiencies, or supply critical nutrients not in the culture media. Expression control sequences can include constitutive and inducible promoters, transcription enhancers, transcription terminators, and the like, which are well known in the art. When two or more nucleic acid molecules are to be coexpressed (e.g., both an antibody heavy and light chain or an antibody VH and VL), both nucleic acid molecules can be inserted, for example, into a single expression vector or in separate expression vectors. For single vector expression, the encoding nucleic acids can be operationally linked to one common expression control sequence or linked to different expression control sequences. The introduction of nucleic acid molecules into a host cell can be confirmed using methods well known in the art. Such methods include, for example, nucleic acid analysis such as Northern blots or polymerase chain reaction (PCR) amplification of mRNA, immunoblotting for expression of gene products, or other suitable analytical methods to test the expression of an introduced nucleic acid sequence or its corresponding gene product. It is understood by those skilled in the art that the nucleic acid molecules are expressed in a sufficient amount to produce a desired product and it is further understood that expression levels can be optimized to obtain sufficient expression using methods well known in the art.

[OHl] General methods in molecular and cellular biochemistry can be found in such standard textbooks as Molecular Cloning: A Laboratory Manual, 3rd Ed. (Sambrook et al.. HaRBor Laboratory Press 2001 ); Short Protocols in Molecular Biology, 4th Ed. (Ausubel et al. eds., John Wiley & Sons 1999); Protein Methods (Bollag etal., John Wiley & Sons 1996); Nonviral Vectors for Gene Therapy (Wagner et al. eds., Academic Press 1999); Viral Vectors (Kaplift & Loewy eds., Academic Press 1995); Immunology Methods Manual (I. Lefkovits ed., Academic Press 1997); and Cell and Tissue Culture: Laboratory Procedures in Biotechnology (Doyle & Griffiths, John Wiley & Sons 1998), the disclosures of which are incorporated herein by reference.

Antibodies and Antigen binding fragments

[0112] An aspect of the present disclosure provides an antibody that binds to the Spike protein of SARS-CoV-2, or an antigen-binding fragment thereof, comprising a VH that comprises a heavy chain CDR1 (HCDR1), a heavy chain CDR2 (HCDR2), and a heavy chain CDR3 (HCDR3); and a VL that comprises a light chain CDR1 (LCDR1), a light chain CDR2 (LCDR2), and a light chain CDR3 (LCDR3). [0113] In some embodiments, the HCDR1 comprises an amino acid sequence of SEQ ID No:

9. In some embodiments, the HCDR1 comprises an amino acid sequence of SEQ ID No: 12. In some embodiments, the HCDR1 comprises an amino acid sequence of SEQ ID No: 15. In some embodiments, the HCDR1 comprises an amino acid sequence of SEQ ID No: 18. In some embodiments, the HCDR1 comprises an amino acid sequence of SEQ ID No: 44. In some embodiments, the HCDR1 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to one of SEQ ID NOs: 9, 12, 15, 18 or 44. In some embodiments, the HCDR1 comprises an amino acid sequence that is 100% identical to one of SEQ ID NOs: 9, 12, 15, 18 or 44 except for the substitution or deletion of one or two amino acids.

[0114] In some embodiments, the HCDR2 comprises an amino acid sequence of SEQ ID No:

10. In some embodiments, the HCDR2 comprises an amino acid sequence of SEQ ID No: 13. In some embodiments, the HCDR2 comprises an amino acid sequence of SEQ ID No: 16. In some embodiments, the HCDR2 comprises an amino acid sequence of SEQ ID No: 19. In some embodiments, the HCDR2 comprises an amino acid sequence of SEQ ID No: 45. In some embodiments, the HCDR2 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to one of SEQ ID NOs: 10, 13, 16, 19 or 45. In some embodiments, the HCDR2 comprises an amino acid sequence that is 100% identical to one of SEQ ID NOs: 10, 13, 16, 19 or 45 except for the substitution or deletion of one or two amino acids.

[0115] In some embodiments, the HCDR3 comprises an amino acid sequence of SEQ ID No:

11. In some embodiments, the HCDR3 comprises an amino acid sequence of SEQ ID No: 14. In some embodiments, the HCDR3 comprises an amino acid sequence of SEQ ID No: 17. In some embodiments, the HCDR3 comprises an amino acid sequence of SEQ ID No: 20. In some embodiments, the HCDR3 comprises an amino acid sequence of SEQ ID No: 46. In some embodiments, the HCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to one of SEQ ID NOs: 11, 14, 17, 20 or 46. In some embodiments, the HCDR3 comprises an amino acid sequence that is 100% identical to one of SEQ ID NOs: 11, 14, 17, 20 or 46 except for the substitution or deletion of one or two amino acids. In some embodiments, the HCDR3 comprises SEQ ID NO: 17, comprising a substitution selected from S99A, G108A, or G108S. In some embodiments, the substitution is S99A. In some embodiments, the substation is G108A. In some embodiments, the substitution is G108S. In some embodiments, the substitutions are S99A and G108A. In some embodiments, the substations are S99A and G108S.

[0116] In some embodiments, the LCDR1 comprises an amino acid sequence of SEQ ID No:

21. In some embodiments, the LCDR1 comprises an amino acid sequence of SEQ ID No: 24. In some embodiments, the LCDR1 comprises an amino acid sequence of SEQ ID No: 27. In some embodiments, the LCDR1 comprises an amino acid sequence of SEQ ID No: 30. In some embodiments, the LCDR1 comprises an amino acid sequence of SEQ ID No: 47. In some embodiments, the LCDR1 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to one of SEQ ID NOs: 21, 24, 27, 30 or 47. In some embodiments, the LCDR1 comprises an amino acid sequence that is 100% identical to one of SEQ ID NOs: 21, 24, 27, 30 or 47 except for the substitution or deletion of one or two amino acids.

[0117] In some embodiments, the LCDR2 comprises an amino acid sequence of SEQ ID No:

22. In some embodiments, the LCDR2 comprises an amino acid sequence of SEQ ID No: 25. In some embodiments, the LCDR2 comprises an amino acid sequence of SEQ ID No: 28. In some embodiments, the LCDR2 comprises an amino acid sequence of SEQ ID No: 31. In some embodiments, the LCDR2 comprises an amino acid sequence of SEQ ID No: 48. In some embodiments, the LCDR2 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to one of SEQ ID NOs: 22, 25, 28, 31 or 48. In some embodiments, the LCDR2 comprises an amino acid sequence that is 100% identical to one of SEQ ID NOs: 22, 25, 28, 31 or 48 except for the substitution or deletion of one or two amino acids.

[0118] In some embodiments, the LCDR3 comprises an amino acid sequence of SEQ ID No:

23. In some embodiments, the LCDR3 comprises an amino acid sequence of SEQ ID No: 26. In some embodiments, the LCDR3 comprises an amino acid sequence of SEQ ID No: 29. In some embodiments, the LCDR3 comprises an amino acid sequence of SEQ ID No: 32. In some embodiments, the LCDR3 comprises an amino acid sequence of SEQ ID No: 49. In some embodiments, the LCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to one of SEQ ID NOs: 23, 26, 29, 32 or 49. In some embodiments, the LCDR3 comprises an amino acid sequence that is 100% identical to one of SEQ ID NOs: 23, 26, 29, 32 or 49 except for the substitution or deletion of one or two amino acids.

[0119] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 9, SEQ ID NO: 10, and SEQ ID NO: 11, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 21, SEQ ID NO: 22, and SEQ ID NO: 23, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 9, SEQ ID NO: 10, and SEQ ID NO: 11, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 21, SEQ ID NO: 22, and SEQ ID NO: 23, respectively.

[0120] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 9, SEQ ID NO: 10, and SEQ ID NO: 11, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 21, SEQ ID NO: 22, and SEQ ID NO: 23, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 9, SEQ ID NO: 10, and SEQ ID NO: 11, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 21, SEQ ID NO: 22, and SEQ ID NO: 23, respectively.

[0121] In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 9, SEQ ID NO: 10, and SEQ ID NO: 11, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 21, SEQ ID NO: 22, and SEQ ID NO: 23, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 9, SEQ ID NO: 10, and SEQ ID NO: 11, respectively; and the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 21, SEQ ID NO: 22, and SEQ ID NO: 23, respectively (antibody Red-E2).

[0122] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 12, SEQ ID NO: 13, and SEQ ID NO: 14, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 24, SEQ ID NO: 25, and SEQ ID NO: 26, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 12, SEQ ID NO: 13, and SEQ ID NO: 14, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 24, SEQ ID NO: 25, and SEQ ID NO: 26, respectively.

[0123] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 12, SEQ ID NO: 13, and SEQ ID NO: 14, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 24, SEQ ID NO: 25, and SEQ ID NO: 26, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 12, SEQ ID NO: 13, and SEQ ID NO: 14, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 24, SEQ ID NO: 25, and SEQ ID NO: 26, respectively.

[0124] In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 12, SEQ ID NO: 13, and SEQ ID NO: 14, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 24, SEQ ID NO: 25, and SEQ ID NO: 26, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 12, SEQ ID NO: 13, and SEQ ID NO: 14, respectively; and the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 24, SEQ ID NO: 25, and SEQ ID NO: 26, respectively (antibody Red-Al).

[0125] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 17, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 17, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively.

[0126] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 17, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 17, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively.

[0127] In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 17, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 17, respectively; and the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively (antibody P4J15).

[0128] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 66, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 66, respectively; and the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively.

[0129] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 67, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 67, respectively; the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively.

[0130] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 68, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 68, respectively; and the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively.

[0131] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 69, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 69, respectively; the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively.

[0132] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 18, SEQ ID NO: 19, and SEQ ID NO: 20, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 30, SEQ ID NO: 31, and SEQ ID NO: 32, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 18, SEQ ID NO: 19, and SEQ ID NO: 20, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 30, SEQ ID NO: 31, and SEQ ID NO: 32, respectively.

[0133] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 18, SEQ ID NO: 19, and SEQ ID NO: 20, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 30, SEQ ID NO: 31, and SEQ ID NO: 32, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 18, SEQ ID NO: 19, and SEQ ID NO: 20, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 30, SEQ ID NO: 31, and SEQ ID NO: 32, respectively.

[0134] In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 18, SEQ ID NO: 19, and SEQ ID NO: 20, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 30, SEQ ID NO: 31, and SEQ ID NO: 32, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 18, SEQ ID NO: 19, and SEQ ID NO: 20, respectively; and the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 30, SEQ ID NO: 31, and SEQ ID NO: 32, respectively (antibody P1N04).

[0135] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 44, SEQ ID NO: 45, and SEQ ID NO: 46, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 47, SEQ ID NO: 48, and SEQ ID NO: 49, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 44, SEQ ID NO: 45, and SEQ ID NO: 46, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence that is at least 32.5%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, or 94% identical to SEQ ID NO: 47, SEQ ID NO: 48, and SEQ ID NO: 49, respectively.

[0136] In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 44, SEQ ID NO: 45, and SEQ ID NO: 46, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 47, SEQ ID NO: 48, and SEQ ID NO: 49, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 comprises an amino acid sequence of SEQ ID NO: 44, SEQ ID NO: 45, and SEQ ID NO: 46, respectively; and the LCDR1, LCDR2, and LCDR3 comprises an amino acid sequence of SEQ ID NO: 47, SEQ ID NO: 48, and SEQ ID NO: 49, respectively.

[0137] In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 44, SEQ ID NO: 45, and SEQ ID NO: 46, respectively. In some embodiments, the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 47, SEQ ID NO: 48, and SEQ ID NO: 49, respectively. In some embodiments, the HCDR1, HCDR2, and HCDR3 sequences consist of SEQ ID NO: 44, SEQ ID NO: 45, and SEQ ID NO: 46, respectively; and the LCDR1, LCDR2, and LCDR3 sequences consist of SEQ ID NO: 47, SEQ ID NO: 48, and SEQ ID NO: 49, respectively (antibody P5-I14).

[0138] In some embodiments, the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical SEQ ID NO: 1. In some embodiments, the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical SEQ ID NO: 2. In some embodiments, the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical SEQ ID NO: 3. In some embodiments, the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical SEQ ID NO: 4. In some embodiments, the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical SEQ ID NO: 42. In some embodiments, the VH comprises at least one amino acid substitutions selected from the group consisting of I4L, W7S, S40P, M43K, M64K, M69I, and N76Y relative to SEQ ID NO: 3.

[0139] In some embodiments, the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical SEQ ID NO: 5. In some embodiments, the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical SEQ ID NO: 6. In some embodiments, the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical SEQ ID NO: 7. In some embodiments, the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical SEQ ID NO: 8. In some embodiments, the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical SEQ ID NO: 43.

[0140] In some embodiments, the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to an amino acid sequence selected from SEQ ID NOs: 1-4 and 42, and the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to an amino acid sequence selected from SEQ ID NOs: 5-8 and 43.

[0141] In some embodiments, the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 1 and the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO:

5.

[0142] In some embodiments, the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 2 and the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO:

6.

[0143] In some embodiments, the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 3 and the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO:

7.

[0144] In some embodiments, the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 4 and the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO:

8.

[0145] In some embodiments, the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 42 and the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 43.

[0146] In some embodiments, the VH comprises an amino acid sequence of SEQ ID NO: 1. In some embodiments, the VH comprises an amino acid sequence of SEQ ID NO: 2. In some embodiments, the VH comprises an amino acid sequence of SEQ ID NO: 3. In some embodiments, the VH comprises an amino acid sequence of SEQ ID NO: 4. In some embodiments, the VH comprises an amino acid sequence of SEQ ID NO: 42. In some embodiments, the VH consists of an amino acid sequence of SEQ ID NO: 1. In some embodiments, the VH consists of an amino acid sequence of SEQ ID NO: 2. In some embodiments, the VH consists of an amino acid sequence of SEQ ID NO: 3. In some embodiments, the VH consists of an amino acid sequence of SEQ ID NO: 4. In some embodiments, the VH consists of an amino acid sequence of SEQ ID NO: 42.

[0147] In some embodiments, the VL comprises an amino acid sequence of SEQ ID NO: 5. In some embodiments, the VL comprises an amino acid sequence of SEQ ID NO: 6. In some embodiments, the VL comprises an amino acid sequence of SEQ ID NO: 7. In some embodiments, the VL comprises an amino acid sequence of SEQ ID NO: 8. In some embodiments, the VL comprises an amino acid sequence of SEQ ID NO: 43. In some embodiments, the VL consists of an amino acid sequence of SEQ ID NO: 5. In some embodiments, the VL consists of an amino acid sequence of SEQ ID NO: 6. In some embodiments, the VL consists of an amino acid sequence of SEQ ID NO: 7. In some embodiments, the VL consists of an amino acid sequence of SEQ ID NO: 8. In some embodiments, the VL consists of an amino acid sequence of SEQ ID NO: 43.

[0148] In some embodiments, the VH comprises an amino acid sequence selected from SEQ

ID NOs: 1-4 and 42, and the VL comprises an amino acid sequence selected from SEQ ID NOs: 5-8 and 43. In some embodiments, the VH consists of an amino acid sequence selected from SEQ ID NOs: 1-4 and 42, and the VL consists of an amino acid sequence selected from SEQ

ID NOs: 5-8 and 43.

[0149] In some embodiments, the VH comprises an amino acid sequence of to the amino acid sequence of SEQ ID NO: 1 and the VL comprises an amino acid sequence of to the amino acid sequence of SEQ ID NO: 5. In some embodiments, the VH consists of an amino acid sequence of to the amino acid sequence of SEQ ID NO: 1 and the VL consists of an amino acid sequence of to the amino acid sequence of SEQ ID NO: 5. In some embodiments, such an antibody, or antigen binding fragment thereof, is referred to herein as Red-E2. [0150] In some embodiments, the VH comprises an amino acid sequence of to the amino acid sequence of SEQ ID NO: 2 and the VL comprises an amino acid sequence of to the amino acid sequence of SEQ ID NO: 6. In some embodiments, the VH consists of an amino acid sequence of to the amino acid sequence of SEQ ID NO: 2 and the VL consists of an amino acid sequence of to the amino acid sequence of SEQ ID NO: 6. In some embodiments, such an antibody, or antigen binding fragment thereof, is referred to herein as Red-Al.

[0151] In some embodiments, the VH comprises an amino acid sequence of to the amino acid sequence of SEQ ID NO: 3 and the VL comprises an amino acid sequence of to the amino acid sequence of SEQ ID NO: 7. In some embodiments, the VH consists of an amino acid sequence of to the amino acid sequence of SEQ ID NO: 3 and the VL consists of an amino acid sequence of to the amino acid sequence of SEQ ID NO: 7. In some embodiments, such an antibody, or antigen binding fragment thereof, is referred to herein as P4J15.

[0152] In some embodiments, the VH comprises an amino acid sequence of to the amino acid sequence of SEQ ID NO: 4 and the VL comprises an amino acid sequence of to the amino acid sequence of SEQ ID NO: 8. In some embodiments, the VH consists of an amino acid sequence of to the amino acid sequence of SEQ ID NO: 4 and the VL consists of an amino acid sequence of to the amino acid sequence of SEQ ID NO: 8. In some embodiments, such an antibody, or antigen binding fragment thereof, is referred to herein as P1N04.

[0153] In some embodiments, the VH comprises an amino acid sequence of to the amino acid sequence of SEQ ID NO: 42 and the VL comprises an amino acid sequence of to the amino acid sequence of SEQ ID NO: 43. In some embodiments, the VH consists of an amino acid sequence of to the amino acid sequence of SEQ ID NO: 42 and the VL consists of an amino acid sequence of to the amino acid sequence of SEQ ID NO: 43. In some embodiments, such an antibody, or antigen binding fragment thereof, is referred to herein as P5-I14.

[0154] Exemplary CDR, VH and VL amino acid sequences of the antibodies of the present disclosure are provided in Tables 1 - 4. Exemplary nucleic acid sequences are provided in Tables 5 and 6.

Table 1: VH amino acid sequences for antibodies

Table 2: VL amino acid sequences for antibodies

Table 3: Heavy chain CDR sequences for antibodies

Table 4: Light chain CDR sequences for antibodies

Table 5: VH nucleotide sequences for antibodies

Table 6: VL nucleotide sequences for antibodies

[0155] In some embodiments, the antibody of the present disclosure is an isolated monoclonal antibody.

[0156] In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure is selected from a human antibody, a canine antibody, a chicken antibody, a goat antibody, a mouse antibody, a pig antibody, a rat antibody, a shark antibody, and a camelid antibody.

[0157] In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure is derived from a human antibody. In some embodiments, the human antibody is selected from a human IgG (human IgGl, human IgG2, human IgG2a, human

IgG2b, human IgG3, human IgG4), human IgM, human IgA (human IgAl, human IgA2), human IgD, human IgE. In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure is derived from a canine antibody. In some embodiments, the canine antibody is selected from a canine IgGA, canine IgGB, canine IgGC, canine IgGD. In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure is derived from a chicken antibody. In some embodiments, the chicken antibody is selected from chicken IgA, chicken IgD, chicken IgE, chicken IgG, chicken IgM, chicken IgY. In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure is derived from a goat antibody. In some embodiments, the goat antibody is goat IgG. In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure is derived from a mouse antibody. In some embodiments, the mouse antibody is mouse IgG. In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure is derived from a pig antibody. In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure is derived from a rat antibody.

Modifications and Variations

[0158] In some embodiments, amino acid sequence variants of the antibodies, or antigenbinding fragments thereof, of the present disclosure are contemplated. For example, it may be desirable to improve the binding affinity and/or other biological properties of the antibody. Amino acid sequence variants of an antibody may be prepared by introducing appropriate modifications into the nucleotide sequence encoding the antibody, or by peptide synthesis. Such modifications include, for example, deletions from, and/or insertions into and/or substitutions of residues within the amino acid sequences of the antibody. Any combination of deletion, insertion, and substitution can be made to arrive at the final construct, provided that the final construct possesses the desired characteristics, such as antigen-binding.

[0159] In some embodiments, a total of 1 to 10 amino acids have been substituted, inserted and/or deleted in SEQ ID NOs: 1-4 and 42 and/or in SEQ ID NOs: 5-8 and 43. In some embodiments, substitutions, insertions, or deletions occur in regions outside the CDRs (for example in the FRs). In some embodiments, the antibody, or an antigen-binding fragment thereof, comprises the VH sequence and/or VL sequences SEQ ID NOs: 1-4 and 42 and/or SEQ ID NOs: 5-8 and 43, including post-translational modifications of that sequence.

[0160] In some embodiments, the antibody, or an antigen-binding fragment thereof, comprises a VH that comprises HCDR1, HCDR2, and HCDR3 sequences and/or a VL that comprises LCDR1, LCDR2, and LCDR3 sequences having at least 30%, 32.5%, 60%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of one or more SEQ ID NOs: 9-32 and 44- 49. In some embodiments, the CDR sequences having at least 30%, 32.5%, 60%, 65%, 70%, 75%, 77.5%, 80%, 82.5%, 85%, 87.5%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identity to the amino acid sequence of one or more SEQ ID NOs: 9-32 and 44-49 contains substitutions (such as conservative substitutions), insertions, or deletions relative to the reference sequence (i.e., SEQ ID NOs: 9-32 and 44-49), but an antibody, or an antigen-binding fragment thereof, comprising that sequence retains the ability to bind to SARS-CoV-2 virus via Spike protein or fragment thereof (for example, the receptor binding domain (RBD), the N- terminal domain (NTD), the subdomain (SD), or the S2 domain). In some embodiments, a total of 1 to 10 amino acids have been substituted, inserted and/or deleted in one or more SEQ ID NOs: 9-32 and 44-49. In some embodiments, substitutions, insertions, or deletions occur in regions outside the CDRs (for example in the FRs). Optionally, the antibody, or an antigenbinding fragment thereof, comprises the CDR sequences SEQ ID NOs: 9-32 and 44-49, including post-translational modifications of that sequence.

[0161] In some embodiments, antibody variants, or antigen binding fragments thereof variants, having one or more amino acid substitutions are provided herein. Sites of interest for substitutional mutagenesis include the CDRs and FRs. More substantial changes are provided in Table 7 and as further described below in reference to amino acid side chain classes. Amino acid substitutions may be introduced into an antibody of interest and the products screened for a desired activity, for example, retained/improved antigen binding, decreased immunogenicity, or improved ADCC or CDC. Table 7 Amino Acid Substitutions - Exemplary Non-Conservative Substitutions

[0162] Amino acids may be grouped according to common side-chain properties:

(a) (1) hydrophobic: Norleucine, Met, Ala, Vai, Leu, He;

(b) (2) neutral hydrophilic: Cys, Ser, Thr, Asn, Gin;

(c) (3) acidic: Asp, Glu;

(d) (4) basic: His, Lys, Arg;

(e) (5) residues that influence chain orientation: Gly, Pro;

(f) (6) aromatic: Trp, Tyr, Phe.

[0163] Non-conservative substitutions will entail exchanging a member of one of these classes for another class. One type of substitutional variant involves substituting one or more hypervariable region residues of a parent antibody (such as a humanized or human antibody). Generally, the resulting variant(s) selected for further study will have modifications (such as improvements) in certain biological properties (for example increased affinity, reduced immunogenicity) relative to the parent antibody and/or will have substantially retained certain biological properties of the parent antibody. An exemplary substitutional variant is an affinity matured antibody, which may be conveniently generated, for example, using phage displaybased affinity maturation techniques such as those described herein. Briefly, one or more CDR residues are mutated and the variant antibodies displayed on phage and screened for a particular biological activity (such as binding affinity). Alterations (such as substitutions) may be made in CDRs, for example, to improve antibody affinity. Such alterations may be made in CDR “hotspots,” /.< ., residues encoded by codons that undergo mutation at high frequency during the somatic maturation process (see for example Chowdhury, Methods Mol. Biol. 207: 179-196 (2008)), and/or SDRs, with the resulting variant VH or VL being tested for binding affinity. Affinity maturation by constructing and reselecting from secondary libraries has been described, for example, in Hoogenboom et al. in Methods in Molecular Biology 178: 1-37 (O'Brien et al., ed., Human Press, Totowa, NJ, (2001).) In some embodiments of affinity maturation, diversity is introduced into the variable genes chosen for maturation by any of a variety of methods (such as, error-prone PCR, chain shuffling, or oligonucleotide-directed mutagenesis). A secondary library is then created. The library is then screened to identify any antibody variants with the desired affinity. Another method to introduce diversity involves CDR-directed approaches, in which several CDR residues (for example, 4-6 residues at a time) are randomized. CDR residues involved in antigen binding may be specifically identified, for example, using alanine scanning mutagenesis or modelling. CDR-H3 and CDR-L3 in particular are often targeted.

[0164] A “conservative amino acid substitution” is one in which the amino acid residue is replaced with an amino acid residue having a side chain with a similar charge. Families of amino acid residues having side chains with similar charges have been defined in the art. These families include amino acids with basic side chains (e.g., lysine, arginine, histidine), acidic side chains (e.g., aspartic acid, glutamic acid), uncharged polar side chains (e.g., glycine, asparagine, glutamine, serine, threonine, tyrosine, cysteine), nonpolar side chains (e.g., alanine, valine, leucine, isoleucine, proline, phenylalanine, methionine, tryptophan), beta-branched side chains (e.g., threonine, valine, isoleucine) and aromatic side chains (e.g, tyrosine, phenylalanine, tryptophan, histidine). Table 8 below list exemplary conservative amino acid substitutions. Alternatively, mutations can be introduced randomly along all or part of the coding sequence, such as by saturation mutagenesis, and the resultant mutants can be screened for biological activity to identify mutants that retain activity. Following mutagenesis, the encoded protein can be expressed and the activity of the protein can be determined.

Table 8: Amino Acid Substitutions - Exemplary Conservative Substitutions

[0165] In some embodiments, substitutions, insertions, or deletions may occur within one or more CDRs so long as such alterations do not substantially reduce the ability of the antibody to bind antigen. For example, conservative alterations (such as conservative substitutions as provided herein) that do not substantially reduce binding affinity may be made in CDRs. Such alterations may be outside of CDR “hotspots” or SDRs. In some embodiments of the variant VH, VL and CDR sequences provided above, each CDR either is unaltered, or contains no more than one, two or three amino acid substitutions.

[0166] Substitution of one or more CDR residues or omission of one or more CDRs is also possible. Antibodies have been described in the scientific literature in which one or two CDRs can be dispensed with for binding. Padlan et al. (1995 FASEB J. 9: 133-139) analyzed the contact regions between antibodies and their antigens, based on published crystal structures, and concluded that only about one fifth to one third of CDR residues actually contact the antigen. Padlan also found many antibodies in which one or two CDRs had no amino acids in contact with an antigen (see also, Vajdos et al. 2002 J Mol Biol 320:415-428).

[0167] CDR residues not contacting antigen can be identified based on previous studies (for example residues H60-H65 in CDRH2 are often not required), from regions of Kabat CDRs lying outside Chothia CDRs, by molecular modeling and/or empirically. If a CDR or residue(s) thereof is omitted, it is usually substituted with an amino acid occupying the corresponding position in another human antibody sequence or a consensus of such sequences. Positions for substitution within CDRs and amino acids to substitute can also be selected empirically.

[0168] A useful method for identification of residues or regions of an antibody that may be targeted for mutagenesis is called “alanine scanning mutagenesis” as described by Cunningham and Wells (1989) Science, 244: 1081-1085. In this method, a residue or group of target residues (for example, charged residues such as Arg, Asp, His, Lys, and Glu) are identified and replaced by a neutral or negatively charged amino acid (such as alanine or polyalanine) to determine whether the interaction of the antibody with antigen is affected. Further substitutions may be introduced at the amino acid locations demonstrating functional sensitivity to the initial substitutions. Alternatively, or additionally, a crystal structure of an antigen-antibody complex to identify contact points between the antibody and antigen. Such contact residues and neighboring residues may be targeted or eliminated as candidates for substitution. Variants may be screened to determine whether they contain the desired properties.

[0169] Amino acid sequence insertions include amino- and/or carboxyl-terminal fusions ranging in length from one residue to polypeptides containing a hundred or more residues, as well as intrasequence insertions of single or multiple amino acid residues. Examples of terminal insertions include an antibody with an N-terminal methionyl residue. Other insertional variants of the antibody molecule include the fusion to the N- or C-terminus of the antibody to an enzyme (e.g., for ADEPT) or a polypeptide which increases the serum half-life of the antibody. [0170] In some embodiments, an antibody, or an antigen binding fragment thereof, of the present disclosure is altered to increase or decrease the extent to which the antibody is glycosylated. Addition or deletion of glycosylation sites to an antibody may be conveniently accomplished by altering the amino acid sequence such that one or more glycosylation sites is created or removed. Where the antibody comprises an Fc region, the carbohydrate attached thereto may be altered. Native antibodies produced by mammalian cells typically comprise a branched, biantennary oligosaccharide that is generally attached by an N-linkage to Asn297 of the CH2 domain of the Fc region. The oligosaccharide may include various carbohydrates, such as, mannose, N-acetyl glucosamine (GlcNAc), galactose, and sialic acid, as well as a fucose attached to a GlcNAc in the “stem” of the biantennary oligosaccharide structure. In some embodiments, modifications of the oligosaccharide in an antibody, or an antigen-binding fragment thereof, of the present disclosure may be made in order to create antibody variants with certain improved properties.

[0171] In some embodiments, antibody variants are provided having a carbohydrate structure that lacks fucose attached (directly or indirectly) to an Fc region. For example, the amount of fucose in such antibody may be from 1% to 80%, from 1% to 65%, from 5% to 65% or from 20% to 40%. The amount of fucose is determined by calculating the average amount of fucose within the sugar chain at Asn297, relative to the sum of all glycostructures attached to Asn 297 (for example, complex, hybrid and high mannose structures) as measured by MALDI-TOF mass spectrometry, as described in WO 2008/077546, for example. Asn297 refers to the asparagine residue located at about position 297 in the Fc region (Eu numbering of Fc region residues); however, Asn297 may also be located about + 3 amino acids upstream or downstream of position 297, /.< ., between positions 294 and 300, due to minor sequence variations in antibodies. Such fucosylation variants may have improved ADCC function. Examples of cell lines capable of producing defucosylated antibodies include Led 3 CHO cells deficient in protein fucosylation and knockout cell lines, such as alpha- 1,6-fucosyltransferase gene, FUT8, knockout CHO cells.

[0172] Antibodies variants are further provided with bisected oligosaccharides, for example, in which a biantennary oligosaccharide attached to the Fc region of the antibody is bisected by GlcNAc. Such antibody variants may have reduced fucosylation and/or improved ADCC function. Examples of such antibody variants are described, for example, in WO 2003/011878, US Patent No. 6,602,684 and US 2005/0123546. Antibody variants with at least one galactose residue in the oligosaccharide attached to the Fc region are also provided. Such antibody variants may have improved CDC function. Such antibody variants are described, for example, in WO 1997/30087, WO 1998/58964 and WO 1999/22764.

[0173] In some embodiments, one or more amino acid modifications may be introduced into the Fc region of an antibody of the present disclosure, thereby generating an Fc region variant. The Fc region variant may comprise a human Fc region sequence (such as a human IgGl, IgG2, IgG3 or IgG4 Fc region) comprising an amino acid modification (such as a substitution) at one or more amino acid positions.

[0174] In some embodiments, the present disclosure contemplates an antibody variant that possesses some but not all effector functions, which make it a desirable candidate for applications in which the half-life of the antibody in vivo is important yet certain effector functions (such as complement and ADCC) are unnecessary or deleterious. In vitro and/or in vivo cytotoxicity assays can be conducted to confirm the reduction/depletion of CDC and/or ADCC activities. For example, Fc receptor (FcR) binding assays can be conducted to ensure that the antibody lacks FcyR binding (hence likely lacking ADCC activity), but retains FcRn binding ability. The primary cells for mediating ADCC, NK cells, express FcyRIII only, whereas monocytes express FcyRI, FcyRII and FcyRIII. Alternatively, non-radioactive assays methods may be employed. Useful effector cells for such assays include peripheral blood mononuclear cells (PBMC) and Natural Killer (NK) cells. Alternatively, or additionally, ADCC activity of the molecule of interest may be assessed in vivo, for example, in an animal model. Clq binding assays may also be carried out to confirm that the antibody is unable to bind Clq and hence lacks CDC activity. To assess complement activation, a CDC assay may be performed. FcRn binding and in vivo clearance/half-life determinations can also be performed using methods known in the art.

[0175] In some embodiments, mutations in the antibody Fc domain were engineered to extend the in vivo half-life of these candidates. These mutations include Met428Leu/Asn434Ser substitutions also known as the LS Xtend mutations by Xencor and the M252Y/S254T/T256E substitutions also known as the YTE mutations. These modified Fc antibodies are expected to extend the half-life of the antibodies by >4-fold compared to wild type IgGl antibodies which could allow for the prophylactic protect of an individual for up to 4 to 6 months with one antibody dose. Unless otherwise noted, amino acid positions in the Fc domain are numbered according to the EU Index. See Edelman et al., The covalent structure of an entire gammaG immunoglobulin molecule. Proc. Natl. Acad. Sci. USA 1969, 63, 78-85; and Kabat, E.A.; National Institutes of Health (U.S.) Office of the Director. Sequences of Proteins of Immunological Interest, 5th ed.; DIANE Publishing: Collingdale, PA, USA, 1991.

[0176] Antibody drugs with the extended in vivo half-life mutations discussed above would allow for circulating levels of antibody to remain high for up to 4 to 6 months with administration of only one therapeutic antibody dose. Given the potency of the discovered antibodies, this single dose is expected to provide an extended prophylactic protection to subjects at risk of infection.

[0177] The extended half-life mutations investigated with the most potent antibodies disclosed herein also represent a significant advantage compared to antibodies in the clinic. The mutations under investigation include Met428Leu/Asn434Ser substitutions and the M252Y/S254T/T256E substitutions can improve the pharmacokinetic properties of the antibodies (extended half-life, higher Cmax, higher AUC and reduced clearance) and potentially improve some of the overall antibody stability properties. Apart from the PK considerations, the LS, DF215 and DF228 substitutions can increase the antibody dependent cytotoxicity (ADCC) and complement dependent cytotoxicity (CDC) functional activities of an antibody such that they have a greater capacity to kill cells infected with the SARS-CoV-2 virus. This increased activity may translate into an additional clinical advantage for the antibodies of the present disclosure.

[0178] In some embodiments, it may be desirable to create cysteine engineered antibodies, for example “thioMAbs,” in which one or more residues of an antibody are substituted with cysteine residues. In particular embodiments, the substituted residues occur at accessible sites of the antibody. By substituting those residues with cysteine, reactive thiol groups are thereby positioned at accessible sites of the antibody and may be used to conjugate the antibody to other moieties, such as drug moieties or linker-drug moieties, to create an immunoconjugate.

[0179] In some embodiments, an anti-SARS-CoV-2antibody of the present disclosure may be further modified to contain additional nonproteinaceous moieties that are known in the art and readily available. The moieties suitable for derivatization of the antibody include but are not limited to water soluble polymers. Non-limiting examples of water-soluble polymers include, but are not limited to, polyethylene glycol (PEG), copolymers of ethylene glycol/propylene glycol, carboxymethylcellulose, dextran, polyvinyl alcohol, polyvinyl pyrrolidone, poly-1, 3- dioxolane, poly-1, 3, 6-trioxane, ethylene/maleic anhydride copolymer, polyaminoacids (either homopolymers or random copolymers), and dextran or poly(n-vinyl pyrrolidone)polyethylene glycol, propropylene glycol homopolymers, proly propylene oxide/ethylene oxide copolymers, poly oxy ethylated polyols (e.g., glycerol), polyvinyl alcohol, and mixtures thereof. Polyethylene glycol propionaldehyde may have advantages in manufacturing due to its stability in water. The polymer may be of any molecular weight, and may be branched or unbranched. The number of polymers attached to the antibody may vary, and if more than one polymer are attached, they can be the same or different molecules. In general, the number and/or type of polymers used for derivatization can be determined based on considerations including, but not limited to, the particular properties or functions of the antibody to be improved, whether the antibody variant will be used in a therapy under defined conditions, etc.

[0180] In some embodiments, conjugates of an antibody and nonproteinaceous moiety that may be selectively heated by exposure to radiation are provided. In some embodiments, the nonproteinaceous moiety is a carbon nanotube. The radiation may be of any wavelength, and includes, but is not limited to, wavelengths that do not harm ordinary cells, but which heat the nonproteinaceous moiety to a temperature at which cells proximal to the antibody- nonproteinaceous moiety are killed.

[0181] In some embodiments, an antibody of the present disclosure is an antibody fragment. Antibody fragments include, but are not limited to, single-chain Fvs (scFv), Fab fragments, F(ab’) fragments, F(ab)2 fragments, F(ab’)2 fragments, disulfide-linked Fvs (dsFv), Fd fragments, Fv fragments, diabody, triabody, tetrabody, and minibody. Diabodies are antibody fragments with two antigen-binding sites that may be bivalent or bispecific. See, for example, EP 404,097; WO 1993/01161; Hudson et al., Nat. Med. 9: 129-134 (2003); and Hollinger et al., Proc. Natl. Acad. Sci. USA 90: 6444-6448 (1993). Triabodies and tetrabodies are also described in Hudson et al., Nat. Med. 9: 129-134 (2003). Single-domain antibodies are antibody fragments comprising all or a portion of the VH or all or a portion of the VL of an antibody. In some embodiments, a single-domain antibody is a human single-domain antibody. Antibody fragments can be made by various techniques, including but not limited to proteolytic digestion of an intact antibody as well as production by recombinant host cells (e.g., E. coli or phage).

[0182] In some embodiments of the antibody, or an antigen-binding fragment thereof, of the present disclosure, the antigen binding fragment is selected from the group consisting of a Fab, a Fab2, a Fab’ single chain antibody, an Fv, a single chain variable fragment (scFv), and a nanobody.

[0183] In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure, or the variant of the present disclosure, further comprising a detectable label fixably attached thereto, wherein the detectable label is selected from the group consisting of fluorescein, DyLight, Cy3, Cy5, FITC, HiLyte Fluor 555, HiLyte Fluor 647, 5-carboxy-2,7- dichlorofluorescein, 5-carboxyfluorescein, 5-FAM, hydroxy tryptamine, 5-hydroxy tryptamine (5-HAT), 6-carboxyfluorescein (6-FAM), FITC, 6-carboxy-l,4-dichloro-2’,7’- di chloro-fluorescein (TET), 6-carboxy-l,4-dichloro-2’,4’,5’,7’-tetra-^,chlorofluorescein (HEX), 6-carboxy-4’,5’-dichloro-2’,7’-dimethoxy-^,fluorescein (6-JOE), an Alexa fluor (Alexa fluor 350, Alexa fluor 405, Alexa fluor 430, Alexa fluor 488, Alexa fluor 500, Alexa fluor 514, Alexa fluor 532, Alexa fluor 546, Alexa fluor 555, Alexa fluor 568, Alexa fluor 594, Alexa fluor 610, Alexa fluor 633, Alexa fluor 635, Alexa fluor 647, Alexa fluor 660, Alexa fluor 680, Alexa fluor 700, Alexa fluor 750), a BODIPY fluorophore (BODIPY 492/515, BODIPY 493/503, BODIPY 500/510, BODIPY 505/515, BODIPY 530/550, BODIPY 542/563, BODIPY 558/568, BODIPY 564/570, BODIPY 576/589, BODIPY 581/591, BODIPY 630/650-X, BODIPY 650/665-X, BODIPY 665/676), FL, FL ATP, Fl-Ceramide, R6G SE, TMR, TMR-X conjugate, TMR-X, SE, TR, TR ATP, TR-X SE, a rhodamine, rhodamine 110, rhodamine 123, rhodamine B, rhodamine B 200, rhodamine BB, rhodamine BG, rhodamine B extra, 5-carboxytetramethylrhodamine (5-TAMRA), 5 GLD, 6-carboxyrhodamine 6G, Lissamine, Lissamine Rhodamine B, Phallicidine, Phalloidine, rhodamine red, Rhod-2, 6- carboxy-X-rhodamine (ROX), carboxy-X-rhodamine (5-ROX), Sulphorhodamine B can C, Sulphorhodamine G Extra, b-carboxytetramethyl-rhodamine (TAMRA), tetramethylrhodamine (TRITC), rhodamine WT, Texas Red, and Texas Red-X.

Humanized, Human, and/or Recombinant Antibodies

[0184] The antibodies disclosed herein can comprise “chimeric” sequences in which a portion of the heavy and/or light chain is identical with or homologous to corresponding sequences in antibodies derived from a particular species or belonging to a particular antibody class or subclass, while the remainder of the chain(s) is identical with or homologous to corresponding sequences in antibodies derived from another species or belonging to another antibody class or subclass, so long as they exhibit the desired biological activity (see U S. Pat. No. 4,816,567; and Morrison, el al. , Proc. Natl. Acad. Sci. USA , 1984, 81 :6851-55).

[0185] The antibodies disclosed herein can be humanized antibodies. A humanized antibody can comprise human framework region and human constant region sequences. In some embodiments, one or more FR region residues of the human immunoglobulin are replaced by corresponding nonhuman residues. In some embodiments, humanized antibodies comprise residues that are not found in the recipient antibody or in the donor antibody. These modifications are made to further refine antibody performance.

[0186] Humanized antibodies can be produced using a variety of techniques known in the art, including but not limited to, CDR-grafting (European Patent No. EP 239,400; International publication No. WO 91/09967; and U S. Patent Nos. 5,225,539, 5,530,101, and 5,585,089), veneering or resurfacing (European Patent Nos. EP 592,106 and EP 519,596; Padlan, Molecular Immunology, 1991, 28(4/5):489-498; Studnicka, et al, Protein Engineering, 1994, 7(6):805- 814; and Roguska, etal., Proc. Natl. Acad. Sci. USA, 1994, 91 :969-73), chain shuffling (U.S. Patent No. 5,565,332), and techniques disclosed in, e.g., U.S. Pat. No. 6,407,213, U.S. Pat. No. 5,766,886, WO 93/17105; Tan, et al., J. Immunol., 2002, 169: 1119-25; Caldas, et al, Protein Eng., 2000, 13(5):353-60; Morea et al, Methods, 2000, 20(3):267-79, Baca, et al., J. Biol. Chem., 1997, 272(16): 10678-84; Roguska, et al, Protein Eng., 1996, 9(10):895 904; Couto, et al, Cancer Res., 1995, 55 (23 Supp):5973s-5977s; Couto, et al, Cancer Res., 1995, 55(8): 1717- 22; Sandhu, J.S., Gene, 1994, 150(2):409-10 and Pedersen, etal, J. Mol. Biol., 1994, 235(3):959-73. See also U.S. Patent Pub. No. US 2005/0042664 Al (Feb. 24, 2005), each of which is incorporated by reference herein in its entirety. In some embodiments, the humanized antibodies are constructed by CDR grafting, in which the amino acid sequences of the six CDRs of the parent non-human antibody (e.g., rodent) are grafted onto a human antibody framework. For example, Padlan, et al. determined that only about one third of the residues in the CDRs actually contact the antigen, and termed these the “specificity determining residues,” or SDRs (Padlan, et al, FASEB J., 1995, 9: 133-9). In the technique of SDR grafting, only the SDR residues are grafted onto the human antibody framework (see, e.g., Kashmiri, et al, Methods, 2005, 36:25-34).

[0187] The choice of human variable domains, both light and heavy, to be used in making the humanized antibodies can be important to reduce antigenicity. For example, according to the so-called “best-fit” method, the sequence of the variable domain of a non-human (e.g., rodent) antibody is screened against the entire library of known human variable-domain sequences. The human sequence that is closest to that of the rodent may be selected as the human framework for the humanized antibody (Sims et al, J. Immunol., 1993, 151 :2296-308; and Chothia et al., J. Mol. Biol., 1987, 196:901-17).

[0188] Another method uses a particular framework derived from the consensus sequence of all human antibodies of a particular subgroup of light or heavy chains. The same framework may be used for several different humanized antibodies (Carter et al, Proc. Natl. Acad. Sci. USA, 1992, 89:4285-89; and Presta etal, J Immunol., 1993, 151 :2623-32). In some embodiments, the framework is derived from the consensus sequences of the most abundant human subclasses, VL6 subgroup I (VL6I) and VH subgroup III (VHIII).

[0189] In an alternative method based on comparison of CDRs, called superhumanization, FR homology is irrelevant. The method consists of comparison of the non-human sequence with the functional human germline gene repertoire. Those genes encoding the same or closely related canonical structures to the murine sequences are then selected. Next, within the genes sharing the canonical structures with the non-human antibody, those with highest homology within the CDRs are chosen as FR donors. Finally, the non-human CDRs are grafted onto these FRs (see, e.g., Tan et al., J. Immunol., 2002, 169: 1119-25).

[0190] Another method for antibody humanization is based on a metric of antibody humanness termed Human String Content (HSC). This method compares the mouse sequence with the repertoire of human germline genes, and the differences are scored as HSC. The target sequence is then humanized by maximizing its HSC rather than using a global identity measure to generate multiple diverse humanized variants (Lazar et al., Mol. Immunol., 2007, 44: 1986-98). [0191] In addition to the methods described above, empirical methods may be used to generate and select humanized antibodies. These methods include those that are based upon the generation of large libraries of humanized variants and selection of the best clones using enrichment technologies or high throughput screening techniques. Antibody variants may be isolated from phage, ribosome, and yeast display libraries as well as by bacterial colony screening (see, e.g., Hoogenboom, Nat. Biotechnol., 2005, 23: 1105-16; Dufner, et ah, Trends Biotechnol., 2006, 24:523-9; Feldhaus, et al., Nat. Biotechnol, 2003, 21 : 163-70; and Schlapschy et al, Protein Eng. Des. Sei, 2004, 17:847-60).

[0192] In the FR library approach, a collection of residue variants are introduced at specific positions in the FR followed by screening of the library to select the FR that best supports the grafted CDR. The residues to be substituted may include some or all of the “Vernier” residues identified as potentially contributing to CDR structure (see, e.g., Foote and Winter, J. Mol. Biol., 1992, 224:487-99), or from the more limited set of target residues identified by Baca, etal, J. Biol. Chem., 1997, 272: 10678-84.

[0193] In FR shuffling, whole FRs are combined with the non-human CDRs instead of creating combinatorial libraries of selected residue variants (see, e.g., DalTAcqua et al, Methods, 2005, 36:43-60). The libraries may be screened for binding in a two-step process, first humanizing VL, followed by VH. Alternatively, a one-step FR shuffling process may be used. Such a process has been shown to be more efficient than the two-step screening, as the resulting antibodies exhibited improved biochemical and physicochemical properties including enhanced expression, increased affinity, and thermal stability (see, e.g., Damschroder, etal., Mol. Immunol., 2007, 44:3049-60).

[0194] The “humaneering” method is based on experimental identification of essential minimum specificity determinants (MSDs) and is based on sequential replacement of non- human fragments into libraries of human FRs and assessment of binding. It begins with regions of the CDR3 of non-human VH and VL chains and progressively replaces other regions of the non-human antibody into the human FRs, including the CDR1 and CDR2 of both VH and VL. This methodology typically results in epitope retention and identification of antibodies from multiple subclasses with distinct human V-segment CDRs. Humaneering allows for isolation of antibodies that are 91-96% homologous to human germline gene antibodies (see, e.g., Alfenito, Cambridge Healthtech Institute’s Third Annual PEGS, The Protein Engineering Summit, 2007).

[0195] The “human engineering” method involves altering a non-human antibody or antibody fragment, such as a mouse or chimeric antibody or antibody fragment, by making specific changes to the amino acid sequence of the antibody so as to produce a modified antibody with reduced immunogenicity in a human that nonetheless retains the desirable binding properties of the original non-human antibodies. Generally, the technique involves classifying amino acid residues of a non-human (e.g., mouse) antibody as “low risk,” “moderate risk,” or “high risk” residues. The classification is performed using a global risk/reward calculation that evaluates the predicted benefits of making particular substitution (e.g., for immunogenicity in humans) against the risk that the substitution will affect the resulting antibody’s folding. The particular human amino acid residue to be substituted at a given position (e.g., low or moderate risk) of a non-human (e.g., mouse) antibody sequence can be selected by aligning an amino acid sequence from the non-human antibody’s variable regions with the corresponding region of a specific or consensus human antibody sequence. The amino acid residues at low or moderate risk positions in the non-human sequence can be substituted for the corresponding residues in the human antibody sequence according to the alignment. Techniques for making human engineered proteins are described in greater detail in Studnicka et al, Protein Engineering, 1994, 7:805-14; U.S. Pat. Nos. 5,766,886; 5,770,196; 5,821,123; and 5,869,619; and PCT Publication WO 93/11794.

[0196] The antibodies disclosed herein can be composite human antibodies. A composite human antibody can be generated using, for example, Composite Human Antibody™ technology (Antitope Ltd., Cambridge, United Kingdom). To generate composite human antibodies, variable region sequences are designed from fragments of multiple human antibody variable region sequences in a manner that avoids T cell epitopes, thereby minimizing the immunogenicity of the resulting antibody. Such antibodies can comprise human constant region sequences, e.g., human light chain and/or heavy chain constant regions.

[0197] The antibodies disclosed herein can be deimmunized antibodies. A deimmunized antibody is an antibody in which T-cell epitopes have been removed. Methods for making deimmunized antibodies have been described (see, e.g., Jones, et al., Methods Mol Biol., 2009, 525:405-23; and De Groot, etal., Cell. Immunol., 2006, 244: 148-153). Deimmunized antibodies comprise T-cell epitope-depleted variable regions and human constant regions. Briefly, VH and VL of an antibody are cloned and T-cell epitopes are subsequently identified by testing overlapping peptides derived from the VH and VL of the antibody in a T cell proliferation assay. T cell epitopes are identified via in silico methods to identify peptide binding to human MHC class II. Mutations are introduced in the VH and VL to abrogate binding to human MHC class II. Mutated VH and VL are then utilized to generate the deimmunized antibody.

[0198] It is further generally desirable that antibodies be humanized with retention of their affinity for the antigen and other favorable biological properties. To achieve this goal, according to one method, humanized antibodies are prepared by a process of analysis of the parental sequences and various conceptual humanized products using three-dimensional models of the parental and humanized sequences. Three-dimensional immunoglobulin models are commonly available and are familiar to those skilled in the art. Computer programs are available which illustrate and display probable three-dimensional conformational structures of selected candidate immunoglobulin sequences. These include, for example, WAM (Whitelegg and Rees, Protein Eng., 2000, 13:819-24), Modeller (Sali and Blundell, J. Mol. Biol., 1993, 234:779-815), and Swiss PDB Viewer (Guex and Peitsch, Electrophoresis, 1997, 18:2714-23). Inspection of these displays permits analysis of the likely role of the residues in the functioning of the candidate immunoglobulin sequence, e.g., the analysis of residues that influence the ability of the candidate immunoglobulin to bind its antigen. In this way, FR residues can be selected and combined from the recipient and import sequences so that the desired antibody characteristic, such as increased affinity for the target antigen(s), is achieved. In general, the CDR residues are directly and most substantially involved in influencing antigen binding.

[0199] The antibodies disclosed herein can be fully human antibodies, which possesses an amino acid sequence corresponding to that of an antibody produced by a human. This definition of a human antibody specifically excludes a humanized antibody comprising non-human antigen-binding residues. Human antibodies can be produced using various techniques known in the art, including phage-display libraries (Hoogenboom and Winter, J. Mol. Biol, 1991, 227:381; Marks, et al, 1991, J. Mol. Biol., 1991, 222:581) and yeast display libraries (Chao, et al, Nature Protocols , 2006, 1 : 755-68). Also available for the preparation of human antibodies are methods described in Cole, et al., Monoclonal Antibodies and Cancer Therapy 77 (1985): Boerner, et al., J. Immunol., 1991, 147(1): 86-95; and van Dijk and van de Winkel, Curr. Opin. Pharmacol, 2001, 5: 368-74. Human antibodies can also be prepared by administering the antigen to a transgenic animal that has been modified to produce such antibodies in response to antigenic challenge, but whose endogenous loci have been disabled, e.g., mice (see, e.g., Jakobovits, Curr. Opin. Biotechnol., 1995, 6(5): 561 -66; Bruggemann and Taussing, Curr. Opin. Biotechnol., 1997, 8(4):455-58; and U.S. Pat. Nos. 6,075,181 and 6,150,584 regarding XENOMOUSE™ technology). See also, for example, Li, et al., Proc. Natl. Acad. Sci. USA , 2006, 103:3557-62, regarding human antibodies generated via a human B-cell hybridoma technology.

[0200] The antibodies disclosed herein can be recombinant human antibodies, which are human antibodies prepared, expressed, created or isolated by recombinant means, such as antibodies expressed using a recombinant expression vector transfected into a host cell, antibodies isolated from a recombinant, combinatorial human antibody library, antibodies isolated from an animal (e.g., a mouse or cow) that is transgenic and/or transchromosomal for human immunoglobulin genes (see e.g., Taylor, L. D., etal, Nucl. Acids Res., 199220:6287-6295) or antibodies prepared, expressed, created or isolated by any other means that involves splicing of human immunoglobulin gene sequences to other DNA sequences. In some embodiments, such recombinant human antibodies can have variable and constant regions derived from human germline immunoglobulin sequences (See Kabat, E. A., et al. (1991) Sequences of Proteins of Immunological Interest Fifth Edition, U.S. Department of Health and Human Services, NIH Publication No. 91-3242). In some embodiments, such recombinant human antibodies are subjected to in vitro mutagenesis (or, when an animal transgenic for human Ig sequences is used, in vivo somatic mutagenesis) and thus the amino acid sequences of the VH and VL regions of the recombinant antibodies are sequences that, while derived from and related to human germline VH and VL sequences, may not naturally exist within the human antibody germline repertoire in vivo.

[0201] In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure is a humanized antibody, a caninized antibody, a chimeric antibody (including a canine-human chimeric antibody, a canine-mouse chimeric antibody, and an antibody comprising a canine Fc), or a CDR-grafted antibody.

Additional Features

[0202] In some embodiments, an antibody of the present disclosure is a multispecific antibody, such as a bispecific antibody. Multispecific antibodies are monoclonal antibodies that have binding specificities for at least two different epitopes. In some embodiments, the at least two different epitopes are from the same antigen. In some embodiments, the at least two different epitopes are from different antigens. In some embodiments, bispecific antibodies may bind to two different epitopes of SARS-CoV-2 virus, such as the amino acid loops on the RBD that form the major contact sites with the ACE-2 receptor and a second epitope that may be nonoverlapping with the first on the RBD, SI domain or within any regions of the Spike trimer. It is conceivable that in binding to two different epitopes on the Spike trimer simultaneously, the resulting bispecific will have an enhanced binding affinity, enhanced neutralization activity and/or greater potential in neutralizing viruses that encode variant amino acid residues within the Spike protein. Bispecific antibodies can be prepared as full-length antibodies or antibody fragments. Techniques for making multispecific antibodies include, but are not limited to, recombinant co-expression of two immunoglobulin heavy chain - light chain pairs having different specificities (known in the art), and “knob-in-hole” engineering (also known in the art, see for example U.S. Patent No. 5,731,168). Multispecific antibodies may also be made by engineering electrostatic steering effects for making antibody Fc-heterodimeric molecules (see for example WO 2009/089004A1); cross-linking two or more antibodies or fragments (see for example US Patent No. 4,676,980); using leucine zippers to produce bi-specific antibodies; using “diabody” technology for making bispecific antibody fragments; and using single-chain Fv (sFv) dimers; and preparing trispecific antibodies. Engineered antibodies with three or more functional antigen binding sites, including “Octopus antibodies,” are also included herein (see for example US 2006/0025576A1). The anti-SARS-CoV-2antibody, or an antigen-binding fragment thereof, of the present disclosure also includes a “Dual Acting FAb” or “DAF” comprising an antigen binding site that binds to Spike protein as well as another, different antigen. In this regard, a DAF could be generated using an antibody described herein combined with an ACE-2 binding antibody fragment that would be capable of blocking the interaction between the viral Spike and ACE-2 receptor used by the virus to enter and infect host target cells.

[0203] In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure is a mono-specific antibody, a bispecific antibody, a tri-specific antibody, a multi-specific antibody, or a multivalent antibody.

[0204] In some embodiments, the antibodies described herein demonstrate advantageous properties over other anti-SARS-CoV2 antibodies described in the art. In some embodiments, the antibodies described herein demonstrate improved affinity for Spike trimer proteins from SARS-CoV-2 variants compared to antibodies described in the art (See e.g., Example 3). In some embodiments, the antibodies described herein demonstrate improved disruption of the interaction between the SARS-CoV-2 viral Spike protein and the ACE-2 receptor See e.g., Example 3). In some embodiments, the antibodies described herein demonstrate improved neutralization of SARS-CoV-2 variants (See e.g., Example 4). An unexpected advantage of the antibodies described herein compared to antibodies described in the art is their optimized potency for the Omicron variant that evolved specific amino acid substitutions in the Spike protein to enhance virus infectivity leading to high levels of transmission, resistance to neutralization from the humoral immune response of infected and/or vaccinated donors and resistance to almost all authorized therapeutic human monoclonal antibodies (2021 (https://doi.org/10.1038/s41586-021-Q4388-0 ) (https://doi.org/10.1038/s41586-022-05Q53-w ) (https://doi.or /10.1101/2022.09.15.5Q7787 ). Furthermore, antibodies described within bind a distinct epitope and maintain activity against virus with mutations that confer resistance to Bebtelovimab, the only authorized antibody that retains potency against all prevalent circulating SARS-CoV-2 variants.

[0205] In some embodiments, an antibody, or an antigen-binding fragment thereof, of the present disclosure has a dissociation constant (Kd) of <1 pM between the P4J15 IgGl antibody and the Omicron BA.l Spike trimer with a Kon rate 3.5 xlO⁵ 1/Ms and a slow Koff rate of <lxl0'⁷ 1/s. P5-I15 IgGl binding to the Spike trimer exhibited a dissociation constant (Kd) of <1 pM with with a Kon rate 6.9 xlO⁴ 1/Ms and Koff rate of <lxl0'⁷ 1/s. Red-E2 IgGl binding to the Spike trimer exhibited a dissociation constant (Kd) of <1 pM with with a Kon rate 3.5 xlO⁵ 1/Ms and Koff rate of <lxl0'⁷ 1/s.

[0206] In some embodiments, the antibodies described herein demonstrate improved neutralization of a SARS-CoV-2 virus or viruses encoding resistance mutations compared to antibodies known in the art. In some embodiments, the antibody Red-E2, or an antigen-binding fragments thereof, exhibit an in vitro neutralization EC50 of a SARS-CoV-2 virus at a concentration less than 50 ng/mL for Red-E2. In some embodiments, the antibodies P4J15 and P5-I14, or an antigen-binding fragments thereof, exhibit an in vitro neutralization EC50 of a SARS-CoV-2 virus at a concentration less than 100 ng/mL. More specifically, the antibody or an antigen-binding fragment thereof, of the present disclosure exhibit an in vitro neutralizing EC50 of Omicron variant SARS-CoV-2 viruses at a concentration of less than 25 ng/ml.

[0207] In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure exhibits an in vitro neutralization EC50 of a SARS-CoV-2 virus at a concentration less than 50 ng/mL for Red-E2 and less than 100 ng/ml for P4J15 and P5-I14. More specifically, the antibody or an antigen-binding fragment thereof, of the present disclosure exhibit an in vitro neutralizing EC50 of Omicron variant SARS-CoV-2 viruses at a concentration of less than 25 ng/ml. In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure, exhibits an in vitro neutralization EC50 of Omicron variant SARS-CoV-2 viruses or viruses encoding resistance mutations of between 2 ng/mL and 25 ng/mL, between 2 ng/mL and 22 ng/mL, between 2 ng/mL and 20 ng/mL, between 2 ng/mL and 17 ng/mL, between 2 ng/mL and 15 ng/mL, between 2 ng/mL and 10 ng/mL, or between 2 ng/mL and 8 ng/mL. In some embodiments, antibodies, or an antigen-binding fragment thereof, described herein exhibit an in vitro neutralization EC50 of Omicron variant SARS-CoV-2 viruses or viruses encoding resistance mutations of about 2 ng/mL, 2.5 ng/mL, 3 ng/mL, 4 ng/mL, 5 ng/mL, 6 ng/mL, 7 ng/mL, 8 ng/mL, 9 ng/mL, 10 ng/mL, 11 ng/mL, 12 ng/mL, 13 ng/mL, 14 ng/mL, 15 ng/mL, 16 ng/mL, 17 ng/mL, 18 ng/mL, 19 ng/mL, 20 ng/mL, 21 ng/mL, 22 ng/mL, 23 ng/mL, 24 ng/mL, or 25 ng/mL.

[0208] In some embodiments, the neutralization capability and/or affinity of an anti-SARS- CoV2 antibody described herein is determined by binding to a coronavirus spike protein. In some embodiments, the spike protein is displayed as part of a lentivirus pseudotyped with the SARS-CoV2 spike protein. In some embodiments, the spike protein is part of a live SARS- CoV-2 virus. In some embodiments, the live SARS-CoV-2 virus is selected from wild type SARS-CoV-2 or a variant of SARS-CoV-2 selected from Alpha (B. l.1.7), Beta (B.1.351), Gamma (P.l), Delta (Bl.617.2), and Omicron (B.1.1.529).

[0209] A neutralizing antibody may be one that exhibits the ability to neutralize, or inhibit, infection of cells by the SARS-CoV-2 virus. In general, a neutralization assay typically measures the loss of infectivity of the virus through reaction of the virus with specific antibodies. Typically, a loss of infectivity is caused by interference by the bound antibody with any of the virus replication steps including but not limited to binding to target cells, entry, and/or viral release. The presence of un-neutralized virus is detected after a predetermined amount of time, for example one, two, three, four, five, six, seven, eight, nine, 10, 12 or 14 days, by measuring the infection of target cells using any of the systems available to the person skilled on the art (for example a luciferase-based system or a cytopathic effect infection assay). [0210] A non-limiting example of a neutralization assay may include combining a given amount of a virus or a SARS-CoV-2 Spike pseudotyped virus (see below) and different concentrations of the test or control (typically positive and negative controls assayed separately) antibody or antibodies are mixed under appropriate conditions (for example one (1) hour at room temperature) and then inoculated into an appropriate target cell culture (for example Vero cells or 293T ACE-2 stable cell line). For instance, the neutralizing antibody-producing cells (for example B cells producing antibodies) may be assayed for the production of SARS-CoV- 2 Spike or RBD antibodies by seeding such cells in separate plates as single cell micro-cultures on human feeder cells in the presence of Epstein-Barr Virus (EBV) (which also stimulate polyclonally memory B cells), a cocktail of growth factors (for example TLR9 agonist CpG- 2006, IL-2 (1000 lU/ml), IL-6 (10 ng/ml), IL-21 (10 ng/ml), and anti-B cell receptor (BCR) goat antibodies (which trigger BCRs). After an appropriate time (e.g., 14 days), supernatants of such cultures may be tested in a primary binding assay (e.g., Luminex assay using Spike trimer coupled beads) and a cell based neutralization assays to monitor B cell clones that produce antibodies capable of preventing viruses or pseudoviruses from productively infecting a target cell. The pseudoviruses may be incubated with B cell culture supernatants for an appropriate time and temperature (for example one (1) h at 37% (5% CO2)) before the addition of host cells (for example 3000 293T ACE-2 stable cells). Incubation for an appropriate time (for example 72 hours) may then follow, after which the supernatant may be removed and Steadylite reagent (Perkin Elmer) added (for example 15 pl). Luciferase activity may then be determined (for example five minutes later) on a Synergy microplate luminometer (BioTek). Decreased luciferase activity relative to a negative control typically indicates virus neutralization. Neutralization assays such as these, suitable for analyzing the neutralizing antibodies, or antigen-binding fragments thereof the neutralizing antibody, or an antigen-binding fragment thereof (binding agents) of this disclosure, are known in the art (see, e.g., Crawford et al Viruses. 2020 May 6;I2(5):5I3. and Nie et al, Nat Protoc. 2020 Nov;15(l l):3699-3715). In some embodiments, neutralization may be determined as a measure of the concentration (for example pg/ml) of an antibody capable of neutralizing any of about 50%, 60%, 70%, 80%, 90%, 95%, or 99% of viral infection (as may be measured by percent neutralization and/or by determining an “EC50” and/or “ECso” value). [0211] In some embodiments, an antibody, or an antigen-binding fragment thereof may be considered neutralizing if it is able to neutralize 50% of viral infection at a concentration of, for instance, about any of 10'⁵, 10'⁴, 10'³, 10'², 10’¹, 10°, 10¹, 10², or 10³ pg/ml (e.g., an ECso value as shown in Figs. 1A-1H, 2A-2H, 3A-3D, and Fig. 4A-4C ). In some embodiments, the ability of a neutralizing antibody to neutralize viral infection may be expressed as a percent neutralization (e.g., 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, or 99% (e.g., as in Figs. 1A-1H, 2A-2H, 3A-3D, and Fig. 4A-4C))

Manufacturing

[0212] An aspect of the present disclosure provides a method of producing the antibody, or an antigen-binding fragment thereof, of the present disclosure comprising culturing a host cell comprising a nucleic acid encoding the antibody, or an antigen-binding fragment thereof, of the present disclosure under a condition suitable for expression of the nucleic acid; and recovering the antibody, or an antigen-binding fragment thereof, produced by the cell. In some embodiments, the method of producing the antibody, or an antigen-binding fragment thereof, of the present disclosure further comprises purifying the antibody, or an antigen-binding fragment thereof.

[0213] Any method known to those of ordinary skill in the art may be used to generate the antibodies, or antigen-binding fragments thereof, of the present disclosure having specificity for (for example binding to) SARS-CoV-2 virus. For instance, to generate and isolate anti- SARS-CoV-2 antibodies from an animal such as a mouse, the mouse may be administered (for example immunized) with one or more SARS-CoV-2 proteins. Animals exhibiting serum reactivity to SARS-CoV-2 expressed on virus infected cells (as determined by, for instance, flow cytometry and / or microscopy) may then be selected for generation of anti- SARS-CoV- 2 hybridoma cell lines. This may be repeated for multiple rounds. Screening may also include, for instance, affinity binding and / or functional characterization to identify the antibody, or an antigen-binding fragment thereof (binding agent) as being specific for SARS-CoV-2. In some embodiments, such as in the Examples herein, subjects (such as humans) may be screened for the expression of antibodies against SARS-CoV-2. In some embodiments, plasma samples of subjects (such as humans) infected by SARS-CoV-2 may be screened to identify subjects expressing antibodies, and in particular, antibodies against the virus, antibody-producing cells of such subjects may then be isolated, followed by the isolation and characterization of the antibodies produced thereby (as in the Examples herein).

[0214] Antibodies may be produced using recombinant methods and compositions, such as described in U.S. Patent No. 4,816,567. For recombinant production of antibodies, or antigen- binding fragments thereof, of the present disclosure, nucleic acids encoding the desired antibodies or antibody fragments of the present disclosure, are isolated and inserted into a replicable vector for further cloning (amplification of the DNA) or for expression. DNA encoding the polyclonal or monoclonal antibodies is readily isolated (for example, with oligonucleotide probes that specifically bind to genes encoding the heavy and light chains of the antibody) and sequenced using conventional procedures. Many cloning and/or expression vectors are commercially available. Vector components generally include, but are not limited to, one or more of the following, a signal sequence, an origin of replication, one or more marker genes, a multiple cloning site containing recognition sequences for numerous restriction endonucleases, an enhancer element, a promoter, and a transcription termination sequence.

[0215] The antibodies or the antigen-binding fragments thereof of the present disclosure may be produced recombinantly not only directly, but also as a fusion protein, where the antibody is fused to a heterologous polypeptide. In some embodiments, the heterologous polypeptide is a signal sequence or other polypeptide having a specific cleavage site at the N-terminus of the mature protein or polypeptide. In some embodiments, the heterologous signal sequence selected is one that is recognized and processed (i.e., cleaved by a signal peptidase) by eukaryotic hostcells. For prokaryotic host-cells that do not recognize and process native mammalian signal sequences, the eukaryotic (i.e., mammalian) signal sequence is replaced by a prokaryotic signal sequence selected, for example, from the group consisting of leader sequences from alkaline phosphatase, penicillinase, Ipp, or heat-stable enterotoxin II genes. For yeast secretion the native signal sequence may be substituted by, for example, the yeast invertase leader, factor leader (including Saccharomyces and Kluyveromyces -factor leaders), or acid phosphatase leader, the C. albicans glucoamylase leader, or the signal described in WO 90/13646. In mammalian cell expression, mammalian signal sequences as well as viral secretory leaders, for example, the herpes simplex virus gD signal, are available. The DNA for such precursor region is ligated in reading frame to the DNA encoding the antibodies or fragments thereof.

[0216] When using recombinant techniques, antibodies or antigen-binding fragments thereof of the present disclosure can be produced intracellularly, in the periplasmic space, or secreted directly into the medium. If the antibodies are produced intracellularly, as a first step, the particulate debris from either host-cells or lysed fragments is removed, for example, by centrifugation or ultrafiltration. A procedure for isolating antibodies which are secreted to the periplasmic space of E. coli is known in the art. Briefly, cell paste is thawed in the presence of sodium acetate (pH 3.5), EDTA, and phenylmethylsulfonylfhioride (PMSF) over about 30 minutes. Cell debris can be removed by centrifugation. Where the antibody is secreted into the medium, supernatants from such expression systems are generally first concentrated using a commercially available protein concentration filter, for example, an Amicon or Millipore Pellicon ultrafiltration unit. A protease inhibitor such as PMSF may be included in any of the foregoing steps to inhibit proteolysis and antibiotics may be included to prevent the growth of adventitious contaminants.

[0217] The antibody or fragment thereof compositions prepared from such cells can be purified using, for example, hydroxylapatite chromatography, gel electrophoresis, dialysis, and affinity chromatography. In some embodiments, affinity chromatography is the purification technique. The suitability of protein A as an affinity ligand depends on the species and isotype of any immunoglobulin Fc domain that is present in the antibody. Protein A can be used to purify antibodies or antibody fragments that are based on human 1, 2, or 4 heavy chains. Protein G is recommended for all mouse isotypes and for human 3 heavy chain antibodies or antibody fragments. The matrix to which the affinity ligand is attached is most often agarose, but other matrices are available. Mechanically stable matrices such as controlled pore glass or poly(styrene-divinyl)benzene allow for faster flow rates and shorter processing times than can be achieved with agarose. Where the antibodies or antibody fragments comprise a CH3 domain, the Bakerbond ABX™resin is useful for purification. Other techniques for protein purification, such as fractionation on an ion-exchange column, ethanol precipitation, Reverse Phase HPLC, chromatography on silica, heparin, SEPHAROSE™, or anion or cation exchange resins (such as a polyaspartic acid column), as well as chromatofocusing, SDS-PAGE, and ammonium sulfate precipitation are also available depending on the antibody or antibody fragment to be recovered.

[0218] Following any preliminary purification step or steps, the mixture comprising the antibody or antibody fragment of interest and contaminants may be subjected to low pH hydrophobic interaction chromatography using an elution buffer at a pH between about 2.5-4.5. In some embodiments, the hydrophobic interaction chromatography is performed at low salt concentrations (e.g., from about 0-0.25 M salt).

[0219] In general, various methodologies for preparing antibodies for use in research, testing, and clinical applications are well-established in the art, consistent with the above-described methodologies and/or as deemed appropriate by one skilled in the art for a particular antibody of interest.

Polynucleotides

[0220] An aspect of the present disclosure provides an isolated nucleic acid or polynucleotide encoding the antibody, or an antigen-binding fragment thereof, of the present disclosure. [0221] Polynucleotides disclosed herein can be at least about 5, at least about 10, at least about 15, at least about 20, at least about 25, at least about 30, at least about 40, at least about 50, at least about 100, at least about 200, at least about 300, at least about 400, at least about 500, at least about 1000, at least about 5000, at least about 10000, or at least about 15000 or more nucleotides in length, as well as all intermediate lengths. It will be readily understood that “intermediate lengths, ” in this context, means any length between the quoted values, such as 6, 7, 8, 9, etc., 101, 102, 103, etc.,- 151, 152, 153, etc.,- 201, 202, 203, etc.

[0222] In some embodiments, the polynucleotide encodes an amino acid sequence comprising the VL and/or an amino acid sequence comprising the VH of the antibody (e.g., the light and/or heavy chains of the antibody).

[0223] In some embodiments, the polynucleotide comprises nucleic acid sequence that is at least 60%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the nucleic acid sequence selected from the group consisting of SEQ ID NOs:33- 40, 50, and 51. In some embodiments, the polynucleotide comprises the nucleic acid sequence selected from the group consisting of SEQ ID NOs:33-40, 50, and 51.

[0224] In some embodiments, the polynucleotide encodes a VH amino acid sequence that is at least 60%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence selected from the group consisting of SEQ ID NOs: 1-4. In some embodiments, the polynucleotide encodes a VL amino acid sequence that is at least 60%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence selected from the group consisting of SEQ ID NOs: 5-8. In some embodiments, the polynucleotide encodes a VH amino acid sequence selected from the group consisting of SEQ ID NOs: 1-4. In some embodiments, the polynucleotide encodes a VL amino acid sequence selected from the group consisting of SEQ ID NOs: 5-8.

[0225] The present disclosure further relates to variants of the polynucleotides disclosed herein. The polynucleotide variants can contain alterations in the coding regions, non-coding regions, or both.

[0226] In some embodiments, a polynucleotide variant contains substitutions, additions, or deletions that alter the properties or activities of the encoded polypeptide. In some embodiments, a polynucleotide variant contains silent substitutions, additions, or deletions that does not alter the properties or activities of the encoded polypeptide. In some embodiments, a polynucleotide variant is produced to modulate or alter expression (or expression levels) of the encoded polypeptide. In some embodiments, a polynucleotide variant is produced to increase expression of the encoded polypeptide. In some embodiments, a polynucleotide variant is produced to decrease expression of the encoded polypeptide. In some embodiments, a polynucleotide variant has increased expression of the encoded polypeptide as compared to a parental polynucleotide sequence. In some embodiments, a polynucleotide variant has decreased expression of the encoded polypeptide as compared to a parental polynucleotide sequence.

[0227] In some embodiments, polynucleotides are codon-optimized. As used herein, the term “codon-optimized” refers to substituting codons in a polynucleotide encoding a polypeptide in order to increase the expression, stability and/or activity of the polypeptide. Factors that influence codon optimization include, but are not limited to one or more of: (i) variation of codon biases between two or more organisms or genes or synthetically constructed bias tables, (ii) variation in the degree of codon bias within an organism, gene, or set of genes, (iii) systematic variation of codons including context, (iv) variation of codons according to their decoding tRNAs, (v) variation of codons according to GC %, either overall or in one position of the triplet, (vi) variation in degree of similarity to a reference sequence for example a naturally occurring sequence, (vii) variation in the codon frequency cutoff, (viii) structural properties of mRNAs transcribed from the DNA sequence, (ix) prior knowledge about the function of the DNA sequences upon which design of the codon substitution set is to be based, (x) systematic variation of codon sets for each amino acid, (xi) isolated removal of spurious translation initiation sites and/or (xii) elimination of fortuitous polyadenylation sites otherwise leading to truncated RNA transcripts.

[0228] It will be appreciated by those of ordinary skill in the art that, as a result of the degeneracy of the genetic code, there are many nucleotide sequences that encode a polypeptide, or fragment of variant thereof, as described herein. Some of these polynucleotides bear minimal homology to the nucleotide sequence of any native gene. Nonetheless, polynucleotides that vary due to differences in codon usage are specifically contemplated in particular embodiments, for example polynucleotides that are optimized for human and/or primate codon selection. Further, alleles of the genes comprising the polynucleotide sequences provided herein may also be used. Alleles are endogenous genes that are altered as a result of one or more mutations, such as deletions, additions and/or substitutions of nucleotides.

[0229] The polynucleotides contemplated herein, regardless of the length of the coding sequence itself, may be combined with other DNA sequences, such as promoters and/or enhancers, untranslated regions (UTRs), signal sequences, Kozak sequences, polyadenylation signals, additional restriction enzyme sites, multiple cloning sites, internal ribosomal entry sites (IRES), recombinase recognition sites (e.g., LoxP, FRT, and Att sites), termination codons, transcriptional termination signals, and polynucleotides encoding self-cleaving polypeptides, epitope tags, as disclosed elsewhere herein or as known in the art, such that their overall length may vary considerably. It is therefore contemplated that a polynucleotide fragment of almost any length may be employed in particular embodiments. In some embodiments, the total length is limited by the ease of preparation and use in the intended recombinant DNA protocol.

Polynucleotides can be prepared, isolated, purified, manipulated, and/or expressed using any of a variety of well-established techniques known and available in the art.

Vectors

[0230] Another aspect of the present disclosure provides a vector comprising a nucleic acid encoding the antibody, or an antigen-binding fragment thereof, of the present disclosure. In some embodiments, the vector of the present disclosure is an expression vector.

[0231] In some embodiments, the vector comprises a polynucleotide comprising a nucleic acid sequence that is at least 60%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the nucleic acid sequence selected from the group consisting of SEQ ID NOs:33-40, 50, and 51. In some embodiments, the vector comprises a polynucleotide comprising a nucleic acid sequence selected from the group consisting of SEQ ID NOs:33-40, 50, and 51.

[0232] In some embodiments, the vector comprises a polynucleotide encoding a VH amino acid sequence that is at least 60%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence selected from the group consisting of SEQ ID NOs: 1-4. In some embodiments, the vector comprises a polynucleotide encoding a VL amino acid sequence that is at least 60%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence selected from the group consisting of SEQ ID NOs: 5-8. In some embodiments, the vector comprises a polynucleotide encoding a VH amino acid sequence selected from the group consisting of SEQ ID NOs: 1-4. In some embodiments, the vector comprises a polynucleotide encoding a VL amino acid sequence selected from the group consisting of SEQ ID NOs: 5-8.

[0233] In order to express the antibody or antigen-binding fragment thereof described herein in a cell, an expression cassette encoding the antibody or antigen-binding fragment thereof can be inserted into a nucleic acid vector. The “expression cassette” contains the encoding the antibody or antigen-binding fragment thereof described herein. The cassette is positionally and sequentially oriented within the vector such that the nucleic acid in the cassette can be transcribed into RNA, and when necessary, translated into a protein or a polypeptide, undergo appropriate post-translational modifications required for activity in the host cell, and be translocated to the appropriate compartment for biological activity by targeting to appropriate intracellular compartments or secretion into extracellular compartments. In some embodiments, the cassette has its 3’ and 5’ ends adapted for ready insertion into a vector, e.g., it has restriction endonuclease sites at each end. The cassette can be removed and inserted into a plasmid or viral vector as a single unit.

[0234] In some embodiments, vectors include, without limitation, plasmids, phagemids, cosmids, transposons, artificial chromosomes such as yeast artificial chromosome (YAC), bacterial artificial chromosome (BAC), or Pl -derived artificial chromosome (PAC), bacteriophages such as lambda phage or Ml 3 phage, and animal viruses. In some embodiments, the coding sequences of the antibody or antigen-binding fragment thereof disclosed herein can be ligated into such vectors for expression in mammalian cells.

[0235] In some embodiments, non-viral vectors are used to deliver one or more polynucleotides contemplated herein. In some embodiments, the vector comprising a polynucleotide encoding the antibody or antigen-binding fragment thereof described herein is a plasmid. Numerous suitable plasmid expression vectors are known to those of skill in the art, and many are commercially available. The following vectors are provided by way of example; for eukaryotic host cells: pXTl, pSG5 (Stratagene), pSVK3, pBPV, pMSG, and pSVLSV40 (Pharmacia). However, any other plasmid vector may be used so long as it is compatible with the host cell.

[0236] In some embodiments, viral vectors are used to deliver one or more polynucleotides contemplated herein. Suitable viral vectors include, but are not limited to, viral vectors based on adenovirus (see, e.g., Li et al., Invest Opthalmol Vis Sci 35:2543 2549, 1994; Borras et al., Gene Ther 6:515 524, 1999; Li and Davidson, PNAS 92:7700 7704, 1995; Sakamoto et al., H Gene Ther 5: 1088 1097, 1999; WO 94/12649, WO 93/03769; WO 93/19191 ; WO 94/28938; WO 95/11984 and WO 95/00655); adeno-associated virus (see, e.g., U.S. Patent No. 7,078,387; Ali et al., Hum Gene Ther 9:81 86, 1998, Flannery et al„ PNAS 94:6916 6921 , 1997; Bennett et al., Invest Opthalmol Vis Sci 38:28572863, 1997; Jomary et al., Gene Ther 4:683 690, 1997, Rolling et al., Hum Gene Ther 10:641 648, 1999; Ali et al., Hum Mol Genet 5:591 594, 1996; Srivastava in WO 93/09239, Samulski et al., J. Vir. (1989) 63:3822-3828; Mendelson et al„ Virol. (1988) 166: 154-165; and Flotte et al., PNAS (1993) 90: 10613-10617); alphaviruses; arenaviruses; baculovirus; herpes simplex virus; human immunodeficiency virus (see, e.g., Miyoshi et al., PNAS 94: 10319 23, 1997; Takahashi et al., J Virol 73:7812 7816, 1999); poliovirus; poxvirus; retrovirus (e.g., Murine Leukemia Virus, spleen necrosis virus, and vectors derived from retroviruses such as Rous Sarcoma Virus, Harvey Sarcoma Virus, avian leukosis virus, a lentivirus, human immunodeficiency virus, myeloproliferative sarcoma virus, and mammary tumor virus); SV40; vaccinia virus; and the like. Examples of vectors are pClneo vectors (Promega) for expression in mammalian cells; pLenti4/V5-DEST™, pLenti6/V5- DEST™, and pLenti6.2/V5-GW/lacZ (Invitrogen) for lentivirus-mediated gene transfer and expression in mammalian cells.

[0237] In some embodiments, the vector is a non-integrating vector, including but not limited to, an episomal vector or a vector that is maintained extrachromosomally. As used herein, the term “episomal” refers to a vector that is able to replicate without integration into host’s chromosomal DNA and without gradual loss from a dividing host cell also meaning that said vector replicates extrachromosomally or episomally. The vector is engineered to harbor the sequence coding for the origin of DNA replication or “ori” from a lymphotrophic herpes virus or a gamma herpesvirus, an adenovirus, SV40, a bovine papilloma virus, or a yeast, specifically a replication origin of a lymphotrophic herpes virus or a gamma herpesvirus corresponding to oriP of EBV. In some embodiments, the lymphotrophic herpes virus may be Epstein Barr virus (EBV), Kaposi’s sarcoma herpes virus (KSHV), Herpes virus saimiri (HS), or Marek’s disease virus (MDV). Epstein Barr virus (EBV) and Kaposi’s sarcoma herpes virus (KSHV) are also examples of a gamma herpesvirus. A viral vector delivered by such viruses or viral particles may be referred to by the type of virus to deliver the viral vector (e.g., a lentiviral vector is a viral vector that is to be delivered by a lentivirus). A viral vector can contain viral elements (e.g., nucleotide sequences) necessary for packaging of the viral vector into the virus or viral particle, replicating the virus, or other desired viral activities. A virus containing a viral vector may be replication competent, replication deficient or replication defective.

[0238] In some embodiments, the vector is an integrating vector. In some embodiments, a polynucleotide is introduced into a target or host cell using a transposon vector system. In some embodiments, the transposon vector system comprises a vector comprising transposable elements and a polynucleotide contemplated herein; and a transposase. In some embodiments, the transposon vector system is a single transposase vector system, see, e.g., WO 2008/027384. Exemplary transposases include, but are not limited to: piggyBac, Sleeping Beauty, Mosl, Tcl/mariner, Tol2, mini-Tol2, Tc3, MuA, Himar I, Frog Prince, and variants thereof. The piggyBac transposon and transposase are described, for example, in U.S. Patent 6,962,810, which is incorporated herein by reference in its entirety. The Sleeping Beauty transposon and transposase are described, for example, in Izsvak et al., J. Mol. Biol. 302: 93-102 (2000), which is incorporated herein by reference in its entirety. The Tol2 transposon which was first isolated from the medaka fish Oryzias latipes and belongs to the hAT family of transposons is described in Kawakami et al. (2000). Mini-Tol2 is a variant of Tol2 and is described in Balciunas et al. (2006). The Tol2 and Mini-Tol2 transposons facilitate integration of a transgene into the genome of an organism when co-acting with the Tol2 transposase. The Frog Prince transposon and transposase are described, for example, in Miskey et al., Nucleic Acids Res. 31 :6873-6881 (2003).

[0239] In some embodiments, a polynucleotide sequence encoding the anti-SARS-CoV-2 antibody or antigen-binding fragment thereof disclosed herein is operably linked to one or more control elements that allow expression of the polynucleotide in both prokaryotic and eukaryotic cells. “Control elements” refer those non-translated regions of the vector which interact with host cellular proteins to carry out transcription and translation. Non-limiting examples of control elements include origin of replication, selection cassettes, constitutive and inducible promoters, enhancers, translation initiation signals (Shine Dalgarno sequence or Kozak sequence) introns, transcription terminators, 5’ and 3’ untranslated regions. See e.g., Bitter et al. (1987) Methods in Enzymology, 153:516-544) Such elements may vary in their strength and specificity. The transcriptional control element may be functional in either a eukaryotic cell (e.g., a mammalian cell) or a prokaryotic cell (e.g., bacterial or archaeal cell).

[0240] The vectors disclosed herein usually contain a promoter that is recognized by the host organism and is operably linked to the nucleic acid encoding the antibodies or the antigenbinding fragments thereof of the present disclosure.

[0241] Promoters suitable for use with prokaryotic hosts include the phoA promoter, lactamase and lactose promoter systems, alkaline phosphatase promoter, a tryptophan promoter system, and hybrid promoters such as the tac promoter, although other known bacterial promoters are also suitable. Promoters for use in bacterial systems also will contain a Shine-Dalgamo (S.D.) sequence operably linked to the DNA encoding the antibodies and antibody fragments.

[0242] Promoter sequences are known for eukaryotes. Virtually all eukaryotic genes have an AT -rich region located approximately 25 to 30 bases upstream from the site where transcription is initiated. Another sequence found 70 to 80 bases upstream from the start of transcription of many genes is a CNCAAT region where N may be any nucleotide. At the 3' end of most eukaryotic genes is an AATAAA sequence that may be the signal for addition of the polyA tail to the 3' end of the coding sequence. All of these sequences may be inserted into eukaryotic expression vectors.

[0243] Examples of suitable promoter sequences for use with yeast hosts include the promoters for 3 -phosphoglycerate kinase or other glycolytic enzymes, such as enolase, glyceraldehyde-3- phosphate dehydrogenase, hexokinase, pyruvate decarboxylase, phospho-fructokinase, glucose-6-phosphate isomerase, 3 -phosphoglycerate mutase, pyruvate kinase, triosephosphate isomerase, phosphoglucose isomerase, and glucokinase. Inducible promoters in yeast have the additional advantage of permitting transcription controlled by growth conditions. Exemplary inducible promoters include the promoter regions for alcohol dehydrogenase 2, isocytochrome C, acid phosphatase, degradative enzymes associated with nitrogen metabolism, metallothionein, glyceraldehyde-3 -phosphate dehydrogenase, and enzymes responsible for maltose and galactose utilization. Suitable vectors and promoters for use in yeast expression are further described in EP 73657. Yeast enhancers also are advantageously used with yeast promoters.

[0244] Transcription of nucleic acids encoding antibodies or fragments thereof from vectors in mammalian host-cells can be controlled, for example, by promoters obtained from the genomes of viruses such as polyoma virus, fowlpox virus, adenovirus (such as Adenovirus 2), bovine papilloma virus, avian sarcoma virus, cytomegalovirus, a retrovirus, hepatitis-B virus, Simian Virus 40 (SV40), by heterologous mammalian promoters, e.g., the actin promoter or an immunoglobulin promoter, and by heat-shock gene promoters, provided such promoters are compatible with the desired host-cell systems.

[0245] The early and late promoters of the SV40 virus are conveniently obtained as an SV40 restriction fragment that also contains the SV40 viral origin of replication. The immediate early promoter of the human cytomegalovirus is conveniently obtained as a Hindlll E restriction fragment. A system for expressing DNA in mammalian hosts using the bovine papilloma virus as a vector is disclosed in U.S. Patent No. 4,419,446. A modification of this system is described in U.S. Patent No. 4,601,978. Alternatively, the Rous Sarcoma Virus long terminal repeat can be used as the promoter.

[0246] Transcription of a DNA encoding the antibodies or fragments thereof by higher eukaryotes is often increased by inserting an enhancer sequence into the vector. Many enhancer sequences are now known from mammalian genes (globin, elastase, albumin, a-fetoprotein, and insulin). Typically, however, one of ordinary skill in the art will use an enhancer from a eukaryotic virus. Examples include the SV40 enhancer on the late side of the replication origin (bp 100-270), the cytomegalovirus early promoter enhancer, the polyoma enhancer on the late side of the replication origin, and adenovirus enhancers. The enhancer may be spliced into the vector at a position 5' or 3' to the antibody-or antibody-fragment encoding sequences. In some embodiments, the enhancer is located at a site 5' of the promoter.

[0247] Vectors used in eukaryotic host-cells (yeast, fungi, insect, plant, animal, human, or nucleated cells from other multicellular organisms) will also contain sequences necessary for the termination of transcription and for stabilizing the mRNA. Such sequences are commonly available from the 5' and, occasionally 3', untranslated regions of eukaryotic or viral DNAs or cDNAs. These regions contain nucleotide segments transcribed as polyadenylated fragments in the untranslated portion of the mRNA encoding antibodies or fragments thereof. One useful transcription termination component is the bovine growth hormone polyadenylation region.

[0248] The vectors disclosed herein may also include nucleotide sequences encoding protein tags (e.g., 6xHis tag, hemagglutinin tag, green fluorescent protein, etc.) that are fused to the site-directed modifying polypeptide, thus resulting in a chimeric polypeptide.

[0249] Methods of introducing polynucleotides and vectors into a host cell are known in the art. Suitable methods include e.g., viral or bacteriophage infection, transfection, conjugation, protoplast fusion, lipofection, electroporation, calcium phosphate precipitation, polyethyleneimine (PEI)-mediated transfection, DEAE-dextran mediated transfection, liposome-mediated transfection, particle gun technology, calcium phosphate precipitation, direct micro injection, nanoparticle-mediated nucleic acid delivery (see, e.g., Panyam et al., Adv Drug Deliv Rev. 2012 Sep 13. pii: SO 169-409X( 12)00283 -9), microfluidics delivery methods (See e.g., International PCT Publication No. WO 2013/059343), and the like.

[0250] In some embodiments, delivery via electroporation comprises mixing the cells with the polynucleotides encoding the antibody or antigen-binding fragment thereof in a cartridge, chamber, or cuvette and applying one or more electrical impulses of defined duration and amplitude. In some embodiments, cells are mixed with polynucleotides encoding the antibody or antigen-binding fragment thereof in a vessel connected to a device (e.g., a pump) which feeds the mixture into a cartridge, chamber, or cuvette wherein one or more electrical impulses of defined duration and amplitude are applied, after which the cells are delivered to a second vessel. Illustrative examples of polynucleotide delivery systems suitable for use in particular embodiments contemplated include, but are not limited to, those provided by Amaxa Biosystems, Maxcyte, Inc., BTX Molecular Delivery Systems, NeonTM Transfection Systems, and Copernicus Therapeutics Inc. Lipofection reagents are sold commercially (e.g., Transfectam™ and Lipofectin™). Cationic and neutral lipids that are suitable for efficient lipofection of polynucleotides have been described in the literature. See e.g., Liu et al. (2003) Gene Therapy. 10: 180-187; and Balazs et al. (2011) Journal of Drug Delivery. 2011 : 1-12.

[0251] In some embodiments, polynucleotides encoding the antibody or antigen-binding fragment thereof described herein are introduced to a cell in a non-viral delivery vehicle, such as a transposon, a nanoparticle (e.g., a lipid nanoparticle), a liposome, an exosome, an attenuated bacterium, or a virus-like particle. In some embodiments, the vehicle is an attenuated bacterium (e.g., naturally or artificially engineered to be invasive but attenuated to prevent pathogenesis including Listeria monocytogenes, certain Salmonella strains, Bifidobacterium longum, and modified Escherichia coli), bacteria having nutritional and tissue-specific tropism to target specific cells, and bacteria having modified surface proteins to alter target cell specificity. In some embodiments, the vehicle is a genetically modified bacteriophage (e.g., engineered phages having large packaging capacity, less immunogenicity, containing mammalian plasmid maintenance sequences and having incorporated targeting ligands). . In some embodiments, the vehicle is a biological liposome. For example, the biological liposome is a phospholipid-based particle derived from human cells (e.g., erythrocyte ghosts, which are red blood cells broken down into spherical structures derived from the subject and wherein tissue targeting can be achieved by attachment of various tissue or cell-specific ligands), secretory exosomes, or subjecti derived membrane-bound nanovescicles (30 -100 nm) of endocytic origin (e.g., can be produced from various cell types and can therefore be taken up by cells without the need for targeting ligands).

[0252] In some embodiments, vectors comprising polynucleotides encoding the antibody or antigen-binding fragment thereof described herein are introduced to cells by viral delivery methods, e.g., by viral transduction. A number of viral based systems have been developed for gene transfer into mammalian cells. For example, retroviruses provide a convenient platform for gene delivery systems. The heterologous nucleic acid can be inserted into a vector and packaged in retroviral particles using techniques known in the art. The recombinant virus can then be isolated and delivered to the engineered mammalian cell in vitro or ex vivo. A number of retroviral systems are known in the art. In some embodiments, adenovirus vectors are used. A number of adenovirus vectors are known in the art. In some embodiments, lentivirus vectors are used. In some embodiments, self-inactivating lentiviral vectors are used. For example, selfinactivating lentiviral vectors carrying the immunomodulator (such as immune checkpoint inhibitor) coding sequence and/or self-inactivating lentiviral vectors carrying chimeric antigen receptors can be packaged with protocols known in the art. The resulting lentiviral vectors can be used to transduce a mammalian cell (such as primary human T cells) using methods known in the art. Vectors derived from retroviruses such as lentivirus are suitable tools to achieve longterm gene transfer, because they allow long-term, stable integration of a transgene and its propagation in progeny cells. Lentiviral vectors also have low immunogenicity, and can transduce nonproliferating cells.

Host Cells

[0253] Another aspect of the present disclosure provides a host cell comprising a nucleic acid encoding the antibody, or an antigen-binding fragment thereof, of the present disclosure or comprising the vector of the present disclosure. In some embodiments, the host cell of the present disclosure is prokaryotic or eukaryotic.

[0254] Suitable host cells for cloning or expressing nucleic acid encoding the antibodies or the antigen-binding fragments thereof of the present disclosure in the vectors described include prokaryotic or eukaryotic cells described herein. For example, antibodies may be produced in bacteria, in particular when glycosylation and Fc effector function are not needed. For expression of antibody fragments and polypeptides in bacteria, see for example U.S. Patent Nos. 5,648,237, 5,789,199, and 5,840,523. After expression, the antibody may be isolated from the bacterial cell paste in a soluble fraction and can be further purified.

[0255] In addition to prokaryotes, eukaryotic microbes such as filamentous fungi or yeast are suitable cloning or expression hosts for antibody-encoding vectors, including fungi and yeast strains whose glycosylation pathways have been “humanized,” resulting in the production of an antibody with a partially or fully human glycosylation pattern.

[0256] Suitable host cells for the expression of glycosylated antibody are also derived from multicellular organisms (invertebrates and vertebrates). Examples of invertebrate cells include plant and insect cells. Numerous baculoviral strains have been identified which may be used in conjunction with insect cells, particularly for transfection of Spodoptera frugiperda cells.

[0257] Plant cell cultures can also be utilized as hosts. See for example US Patent Nos. 5,959,177, 6,040,498, 6,420,548, 7,125,978, and 6,417,429 (describing PLANTIBODIES™ technology for producing antibodies in transgenic plants).

[0258] Vertebrate cells may also be used as hosts. For example, mammalian cell lines that are adapted to grow in suspension may be useful. Other examples of useful mammalian host cell lines are monkey kidney CV1 line transformed by SV40 (COS-7); human embryonic kidney line (293 or 293 cells; baby hamster kidney cells (BHK); mouse Sertoli cells (TM4 cells); monkey kidney cells (CV1); African green monkey kidney cells (VERO-76); human cervical carcinoma cells (HELA); canine kidney cells (MDCK; buffalo rat liver cells (BRL 3 A); human lung cells (W138); human liver cells (Hep G2); mouse mammary tumor (MMT 060562); TRI cells; MRC 5 cells; and FS4 cells. Other useful mammalian host cell lines include Chinese hamster ovary (CHO) cells, including DHFR- CHO cells; and myeloma cell lines such as Y0, NSO and Sp2/0.

[0259] In some embodiments, host-cells are transformed with the above-described vectors for antibody or antigen-binding fragment production are cultured in conventional nutrient media modified as appropriate for inducing promoters, selecting transformants, or amplifying the genes encoding the desired sequences. Commercially available media such as Ham's F10 (Sigma), Minimal Essential Medium ((MEM), Sigma), RPMI-1640 (Sigma), and Dulbecco's Modified Eagle's Medium ((DMEM), Sigma) are suitable for culturing the host-cells. Any of these media may be supplemented as necessary with hormones and/or other growth factors (such as insulin, transferrin, or epidermal growth factor), salts (such as sodium chloride, calcium, magnesium, and phosphate), buffers (such as HEPES), nucleotides (such as adenosine and thymidine), antibiotics (such as GENT MYCIN™ drug), trace elements (defined as inorganic compounds usually present at final concentrations in the micromolar range), and glucose or an equivalent energy source. Any other necessary supplements may also be included at appropriate concentrations that would be known to those skilled in the art. The culture conditions, such as temperature, pH, and the like, are those previously used with the host-cell selected for expression, and will be apparent to the person skilled in the art.

[0260] In some embodiments, a host cell comprising one or more nucleic acids encoding an antibody or an antigen-binding fragment thereof of the present disclosure is provided. In one such embodiment, a host cell comprises (for example, has been transformed with): (1) a vector comprising a nucleic acid that encodes an amino acid sequence comprising the VL of the antibody and an amino acid sequence comprising the VH of the antibody, or (2) a first vector comprising a nucleic acid that encodes an amino acid sequence comprising the VL of the antibody and a second vector comprising a nucleic acid that encodes an amino acid sequence comprising the VH of the antibody. In some embodiments, the host cell is eukaryotic, for example a Chinese Hamster Ovary (CHO) cell or lymphoid cell (such as Y0, NSO, Sp20 cell). In some embodiments, a host cell comprises a nucleic acid encoding a VH amino acid sequence that is at least 75%, 80%, 87.5%, or 90% identical to the amino acid sequence selected from the group consisting of SEQ ID NOs: 1-4. In some embodiments, a host cell comprises a nucleic acid encoding a VL amino acid sequence that is at least 75%, 80%, 87.5%, or 90% identical to the amino acid sequence selected from the group consisting of SEQ ID NOs: 5-8. In some embodiments, a host cell comprises a nucleic acid encoding a VH amino acid sequence selected from the group consisting of SEQ ID NOs: 1-4. In some embodiments, a host cell comprises a nucleic acid encoding a VL amino acid sequence selected from the group consisting of SEQ ID NOs: 5-8. In some embodiments, a method of making an antibody of the present disclosure is provided, wherein the method comprises culturing a host cell comprising a nucleic acid encoding the antibody, as provided above, under conditions suitable for expression of the antibody, and optionally recovering the antibody from the host cell (or host cell culture medium). In some embodiments, the host cell is a 293T cell. [0261] In some embodiments, an antibody of the present disclosure is produced by a method comprising culturing a host cell comprising one or more nucleic acids encoding an antibody described herein, under a condition suitable for expression of the one or more nucleic acids, and recovering the antibody produced by the cell. In some embodiments, the one or more nucleic acids encode a VH amino acid sequence that is at least 75%, 80%, 87.5%, or 90% identical to the amino acid sequence selected from the group consisting of SEQ ID NOs: 1-4. In another further embodiment, the one or more nucleic acids encode a VL amino acid sequence that is at least 75%, 80%, 87.5%, or 90% identical to the amino acid sequence selected from the group consisting of SEQ ID NOs: 5-8. In some embodiments, the one or more nucleic acids encode a VH amino acid sequence selected from the group consisting of SEQ ID NOs: 1-4. In another further embodiment, the one or more nucleic acids encode a VL amino acid sequence selected from the group consisting of SEQ ID NOs: 5-8. In some embodiments, the antibody of the present disclosure produced by a method comprising culturing a host cell comprising one or more nucleic acids encoding an antibody described herein has a lysine residue removed from the C-terminus. In some embodiments, the host cell is a 293T cell.

Methods of Detection and Kits

[0262] Another aspect of the present disclosure provides a method for detecting SARS-CoV-2 virus in a cell or on a cell, the method comprising contacting a test biological sample with one or more antibodies, or antigen-binding fragments thereof, of the present disclosure or one or more variants of the present disclosure and detecting the antibody, or an antigen-binding fragment thereof, bound to the biological sample or components thereof.

[0263] In some embodiments, the method for detecting SARS-CoV-2 virus in a cell or on a cell further comprises comparing the amount of binding to the test biological sample or components thereof to the amount of binding to a control biological sample or components thereof, wherein increased binding to the test biological sample or components thereof relative to the control biological sample or components thereof indicates the presence of a cell expressing SARS- CoV-2 in the test biological sample.

[0264] Another aspect of the present disclosure provides a method for detecting a SARS-CoV- 2 virus in a sample, the method comprising contacting the sample with the antibody, or antigenbinding fragment thereof, of the present disclosure and detecting the antibody in the sample.

[0265] In some embodiments for detecting a SARS-CoV-2 virus in a sample, the method further comprises comparing the amount of the antibody detected in the sample to the amount of the antibody detected in a control sample, wherein increased detection of the antibody in the sample relative to the control sample indicates the presence of the SARS-CoV-2 virus in the test biological sample.

[0266] In some embodiments for detecting a SARS-CoV-2 virus in a sample, the SARS-CoV- 2 virus is selected from wild type SARS-CoV-2 or a variant of SARS-CoV-2 selected from Alpha (B.1.1.7), Beta (B.1.351), Gamma (P. l), Delta (Bl.617.2), and Omicron (B.1.1.529). In some embodiments, the SARS-CoV-2 virus is selected from a wild type SARS-CoV-2 virus or a variant selected from Alpha (B.l.1.7), Beta (B.1.351), Gamma (P.l), Delta (B.1.617.2), Omicron (B.1.1.529), CAL.C20, Mink variant 16, Lambda (C.37), and Mu (B.1.621).

[0267] In some embodiments for detecting a SARS-CoV-2 virus in a sample, the sample is selected from the group consisting of blood, serum, nasopharyngeal and/or nasal swabs, anal swabs, bronchoalveolar lavage, cerebrospinal fluid, nasal-throat swab, throat swab, sputum, a cell, and tissue (such as liver tissue from a liver biopsy).

[0268] The term “detecting” as used herein encompasses quantitative or qualitative detection.

[0269] In some embodiments of the present disclosure, any of the antibodies, or the antigenbinding fragments thereof, of the present disclosure is useful for detecting the presence of SARS-CoV-2 virus and/or Spike protein or fragment thereof in a biological sample.

[0270] In some embodiments of the present disclosure, the antibodies, or the antigen-binding fragments thereof, of the present disclosure for use in a method of diagnosis or detection is provided. In a further aspect, a method of detecting the presence of SARS-CoV-2 in a biological sample is provided. In some embodiments, the method comprises contacting the biological sample with one or more antibodies, or the antigen-binding fragments thereof, of the present disclosure under conditions permissive for binding of the antibody, or the antigen-binding fragment thereof, of the present disclosure to SARS-CoV-2, and detecting whether a complex is formed between the antibody, or the antigen-binding fragment thereof, of the present disclosure and SARS-CoV-2. Such method may be an in vitro or in vivo method.

[0271] In a further aspect, a method of detecting the presence of Spike protein or fragment thereof (for example, the receptor binding domain (RBD), the N-terminal domain (NTD), the subdomain (SD), or the S2 domain) in a biological sample is provided. In some embodiments, the method comprises contacting the biological sample with one or more antibodies, or antigenbinding fragments thereof, of the present disclosure under conditions permissive for binding of the antibody, or the antigen-binding fragment thereof to Spike protein or fragment thereof (for example, the receptor binding domain (RBD), the N-terminal domain (NTD), the subdomain (SD), or the S2 domain), and detecting whether a complex is formed between the antibody or the antigen-binding fragment thereof and Spike protein or fragment thereof (for example, the receptor binding domain (RBD), the N-terminal domain (NTD), the subdomain (SD), or the S2 domain). Such method may be an in vitro or in vivo method.

[0272] In some embodiments, the antibodies, or the antigen-binding fragments thereof, of the present disclosure are used to select subjects eligible for therapy with the antibodies, or the antigen-binding fragments thereof, of the present disclosure, such as where SARS-CoV-2 or RBD, or Spike protein or fragment thereof is a biomarker for selection of patients.

[0273] In yet a further aspect, there is provided a diagnostic test apparatus and method for determining or detecting the presence of SARS-CoV-2 in a sample. The apparatus may comprise, as a reagent, one or more antibodies, or the antigen-binding fragments thereof, of the present disclosure. The antibody/ies may, for example, be immobilized on a solid support (for example, on a microtiter assay plate, or on a particulate support) and serve to “capture” SARS- CoV-2 from a sample (such as a blood or serum sample or other clinical specimen - such as a liver biopsy). The captured virus may then be detected by, for example, adding a further, labeled, reagent which binds to the captured virus. Conveniently, the assay may take the form of an ELISA, especially a sandwich-type ELISA, but any other assay format could in principle be adopted (such as radioimmunoassay, Western blot) including immunochromatographic or dipstick-type assays.

[0274] For diagnostic purposes, the antibodies, or the antigen-binding fragments thereof, of the present disclosure may either be labeled or unlabeled. Unlabeled antibodies can be used in combination with other labeled antibodies (second antibodies). Alternatively, the antibodies can be directly labeled. A wide variety of labels may be employed - such as radionuclides, fluors, enzymes, enzyme substrates, enzyme cofactors, enzyme inhibitors, ligands (particularly haptens), etc. Labels include, but are not limited to, labels or moieties that are detected directly (such as fluorescent, chromophoric, electron-dense, chemiluminescent, and radioactive labels), as well as moieties, such as enzymes or ligands, that are detected indirectly, e.g., through an enzymatic reaction or molecular interaction. Exemplary labels include, but are not limited to, the radioisotopes 32 P, 14 C, 125 I, 3 H, and 131 I, fluorophores such as rare earth chelates or fluorescein and its derivatives, rhodamine and its derivatives, dansyl, umbelliferone, luceriferases, such as firefly luciferase and bacterial luciferase, luciferin, 2,3- dihydrophthalazinediones, horseradish peroxidase (HRP), alkaline phosphatase, P- galactosidase, glucoamylase, lysozyme, saccharide oxidases, such as glucose oxidase, galactose oxidase, and glucose-6-phosphate dehydrogenase, heterocyclic oxidases such as uricase and xanthine oxidase, coupled with an enzyme that employs hydrogen peroxide to oxidize a dye precursor such as HRP, lactoperoxidase, or microperoxidase, biotin/avidin, spin labels, bacteriophage labels, stable free radicals, and the like.

[0275] In some embodiments, the test biological sample is compared to a control biological sample. In some embodiments, the control biological sample is from an individual known not to be infected with the SARS-CoV-2 virus. In some embodiments, the control biological sample is from an individual known to be infected with SARS-CoV-2.

[0276] In some embodiments, any of the methods of treatment and/or attenuation of a SARS- CoV-2 virus infection described in the present disclosure are based on the determination or detection of SARS-CoV-2 in a sample by any of the antibodies or antigen-binding fragments thereof of the present disclosure. As used herein, “based upon” includes (1) assessing, determining, or measuring the subject's characteristics as described herein, and/or selecting a subject suitable for receiving treatment); and (2) administering the treatment(s) as described herein.

[0277] In some embodiments, a method is provided for identifying an individual suitable or not suitable (unsuitable) for treatment with the antibodies or antigen-binding fragments thereof of the present disclosure. In some embodiments, an individual suitable for treatment is administered a neutralizing antibody or an antigen-binding fragment thereof of the present disclosure.

[0278] In some embodiments, a method is providing for selecting or not selecting an individual for treatment with the antibodies or antigen-binding fragments thereof of the present disclosure, the method comprising: a) assessing the viral load and/or viral titer in a biological sample from the individual, and b) selecting the individual for treatment with an anti-SARS-CoV-2 antibody or an antigen-binding fragment thereof of the present disclosure if the viral load is at least 5 lU/mL. In some embodiments, the viral load is at least 5xl0² copies per ml, 10³ copies per ml, 10⁴ copies per ml, 10⁵ copies per ml, 10⁶ copies per ml, 10⁷ copies per ml, or > 10⁷ copies per ml inclusive, including any values in between these numbers.

[0279] In a further aspect of the present disclosure, there is provided an assay method for identifying an agent that improves or enhances the efficacy of the neutralizing activity of the antibodies or antigen-binding fragments thereof of the present disclosure. Provided herein is an assay method for identifying an agent that improves or enhances the efficacy of the neutralizing activity of the antibodies or antigen-binding fragments thereof of the present disclosure against SARS-CoV-2 virus, comprising the steps of: (a) contacting said antibody or antigen-binding fragment thereof and an agent to be tested with a sample; and (b) determining whether the agent improves or enhances the efficacy of the antibody or antigen-binding fragment thereof in neutralizing the infectivity of SARS-CoV-2 virus. In some embodiments, the ability of the agent to improve or enhance the efficacy of the neutralizing activity of the antibody or antigenbinding fragment thereof of the present disclosure against SARS-CoV-2 virus is compared to a control. In some embodiments, the control is the antibody or antigen-binding fragment thereof of the present disclosure in the absence of the agent. In some embodiments, the control is humanized antibody or fragment thereof with a placebo, e.g. , water, saline, sugar water, etc. As used herein, the term “agent” may be a single entity or it may be a combination of entities. The agent may be an organic compound or other chemical. The agent may be a compound, which is obtainable from or produced by any suitable source, whether natural or artificial. The agent may be an amino acid molecule, a polypeptide, or a chemical derivative thereof, or a combination thereof. The agent may even be a polynucleotide molecule - which may be a sense or an anti-sense molecule. In some embodiments, the agent is an antibody. In some embodiments, the agent is a cytokine (such as interferon- a). In some embodiments, the agent is a direct acting antiviral agent. In further embodiments, the direct acting antiviral agent is viral protease inhibitor or a viral polymerase inhibitor. In some embodiments, the agent is an indirect acting viral agent. The agent may be designed or obtained from a library of compounds, which may comprise peptides, as well as other compounds, such as small organic molecules. By way of example, the agent may be a natural substance, a biological macromolecule, or an extract made from biological materials such as bacteria, fungi, or animal (particularly mammalian) cells or tissues, an organic or an inorganic molecule, a synthetic agent, a semi- synthetic agent, a structural or functional mimetic, a peptide, a peptidomimetics, a derivatized agent, a peptide cleaved from a whole protein, or a peptides synthesized synthetically (such as, by way of example, either using a peptide synthesizer or by recombinant techniques or combinations thereof, a recombinant agent, an antibody, a natural or a non-natural agent, a fusion protein or equivalent thereof and mutants, variants or combinations thereof. Typically, the agent will be an organic compound. Typically, the organic compounds will comprise two or more hydrocarbyl groups. Here, the term “hydrocarbyl group” means a group comprising at least C and H and may optionally comprise one or more other suitable substituents. Examples of such substituents may include halo-, alkoxy-, nitro-, an alkyl group, a cyclic group etc. In addition to the possibility of the substituents being a cyclic group, a combination of substituents may form a cyclic group. If the hydrocarbyl group comprises more than one C then those carbons need not necessarily be linked to each other. For example, at least two of the carbons may be linked via a suitable element or group. Thus, the hydrocarbyl group may contain hetero atoms. Suitable hetero atoms will be apparent to those skilled in the art and include, for instance, sulphur, nitrogen and oxygen. For some applications, the agent comprises at least one cyclic group. The cyclic group may be a polycyclic group, such as a non-fused polycyclic group. For some applications, the agent comprises at least the one of said cyclic groups linked to another hydrocarbyl group. The agent may contain halo groups. Here, “halo” means fluoro, chloro, bromo or iodo. The agent may contain one or more of alkyl, alkoxy, alkenyl, alkylene and alkenylene groups - which may be unbranched- or branched-chain.

[0280] Another aspect of the present disclosure provides a kit for detecting SARS-CoV-2 virus in a cell or on a cell, the kit comprising the one or more antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure and instructions for use. In some embodiments of the kit of the present disclosure, the antibody, or an antigenbinding fragment thereof, the variant of the present disclosure is in lyophilized form.

[0281] Another aspect of the present disclosure provides a kit for detecting SARS-CoV-2 virus in a sample, the kit comprising the one or more antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure and instructions for use. In some embodiments of the kit of the present disclosure, the antibody, or an antigenbinding fragment thereof, the variant of the present disclosure is in lyophilized form.

[0282] In some embodiments, the kit containing the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure useful for the detection of SARS-CoV-2 virus in a sample, in a cell or on a cell, the treatment, prevention and/or diagnosis of the disorders described above is provided.

[0283] In some embodiments, the kit of the present disclosure comprises a container and a label or package insert on or associated with the container. Suitable containers include, for example, bottles, vials, syringes, IV solution bags, etc. The containers may be formed from a variety of materials such as glass or plastic. The container holds a composition which is by itself or combined with another composition effective for treating, preventing and/or diagnosing the condition and may have a sterile access port (for example the container may be an intravenous solution bag or a vial having a stopper pierceable by a hypodermic injection needle). At least one active agent in the composition is an antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure. The label or package insert indicates that the composition is used for diagnosing and/or treating the condition of choice. Moreover, the kit may comprise (a) a first container with a composition contained therein, wherein the composition comprises an antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure; and (b) a second container with a composition contained therein, wherein the composition comprises a further cytotoxic or otherwise therapeutic agent. The article of manufacture or kit in this embodiment of the present disclosure may further comprise a package insert indicating that the compositions can be used to treat a particular condition. Alternatively, or additionally, the article of manufacture or kit may further comprise a second (or third) container comprising a pharmaceutically-acceptable buffer, such as bacteriostatic water for injection (BWFI), phosphate-buffered saline, Ringer's solution and dextrose solution. It may further include other materials desirable from a commercial and user standpoint, including other buffers, diluents, filters, needles, and syringes. [0284] In some embodiments, the kit of the present disclosure is a diagnostic kit, for example, research, detection and/or diagnostic kit. Such kits typically contain the antibody, or an antigenbinding fragment thereof, of the present disclosure or the variant of the present disclosure. Suitably, the antibody is labeled, or a secondary labeling reagent is included in the kit. In some embodiments, the kit is labeled with instructions for performing the intended application, for example, for performing an in vivo imaging assay.

Compositions

[0285] Another aspect of the present disclosure provides a pharmaceutical composition comprising one or more antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure, and a pharmaceutically acceptable carrier.

[0286] In some embodiments, the pharmaceutical composition of the present disclosure comprises the antibody Red-E2 of the present disclosure and one or more antibodies of the present disclosure selected from the group consisting of P4J15, P5-I14, Red-Al and P1N04. In some embodiments, the pharmaceutical composition of the present disclosure comprises the antibody P4J15 of the present disclosure and one or more antibodies of the present disclosure selected from the group consisting of Red-E2, P5-I14, Red-Al and P1N04. In some embodiments, the pharmaceutical composition of the present disclosure comprises the antibody P5-I14 of the present disclosure and one or more antibodies of the present disclosure selected from the group consisting of Red-E2, P4J15, Red-Al and P1N04. In some embodiments, the pharmaceutical composition of the present disclosure comprises the antibody Red-E2 of the present disclosure and the antibody P4J15 of the present disclosure. In some embodiments, the pharmaceutical composition of the present disclosure comprises the antibody Red-E2 of the present disclosure and the antibody P5-I14 of the present disclosure. In some embodiments, the pharmaceutical composition of the present disclosure comprises the antibody P5-I14 of the present disclosure and the antibody P4J15 of the present disclosure. [0287] In some embodiments, the pharmaceutical composition comprises an antibody, or an antigen-binding fragment thereof, of the present disclosure and a pharmaceutically acceptable carrier.

[0288] In some embodiments, the pharmaceutical composition of the present disclosure comprises two antibodies, wherein the first antibody is the Red-E2 antibody of the present disclosure and the second antibody is selected from P4J15, P5-I14, Red-Al and P1N04 of the present disclosure. In some embodiments, the pharmaceutical composition of the present disclosure comprises two antibodies, wherein the first antibody is the P4J15 antibody of the present disclosure and the second antibody is selected from Red-E2, P5-I14, Red-Al and P1N04 of the present disclosure. In some embodiments, the pharmaceutical composition of the present disclosure comprises two antibodies, wherein the first antibody is the P5-I14 antibody of the present disclosure and the second antibody is selected from P4J15, Red-E2, Red-Al and P1N04 of the present disclosure. In some embodiments, the first antibody is the Red-E2 antibody of the present disclosure and the second antibody is P4J15 of the present disclosure or P5-I14 of the present disclosure. In some embodiments, the pharmaceutical composition of the present disclosure comprises a first and a second antibody, wherein the first antibody is P5-I14 antibody of the present disclosure and the second antibody is P4J15 of the present disclosure.

[0289] Furthermore, antibodies of the present disclosure Red-E2, P4J15 and/or P5-I14 in binding distinct epitopes could be used to enhance the pharmaceutical efficacy and extend the neutralizing breadth against current and future SARS-CoV-2 variants when used in combination with anti-SARS-CoV-2 neutralizing antibodies binding the Class 3 epitope, such as P2G3 as disclosed in WO2022/263638 and Bebtelovimab as disclosed in WO2022/072919. Thus in further embodiments, the pharmaceutical composition of the present disclosure comprises at least one first antibody of the present disclosure selected from the group consisting of Red-E2, P4J15 and/or P5-I14 and at least one second antibody selected from P2G3 and/or Bebtelovimab.

[0290] In some embodiments, the pharmaceutical composition of the present disclosure comprises two or more antibodies, wherein the first antibody is the Red-E2 antibody of the present disclosure, and the second or more antibodies are selected from:

(a) the P4J 15 antibody of the present disclosure;

(b) the P5-I14 antibody of the present disclosure;

(c) Bebtelovimab;

(d) the P2G3 antibody; and (e) a combination thereof.

[0291] In some embodiments, the pharmaceutical composition of the present disclosure comprises two or more antibodies, wherein the first antibody is the P4J15 antibody of the present disclosure, and the second or more antibodies are selected from:

(a) the Red-E2 antibody of the present disclosure;

(b) the P5-I14 antibody of the present disclosure;

(c) Bebtelovimab;

(d) the P2G3 antibody; and

(e) a combination thereof.

[0292] In some embodiments, the pharmaceutical composition of the present disclosure comprises two or more antibodies, wherein the first antibody is the P5-I14 antibody of the present disclosure, and the second or more antibodies are selected from:

(a) the P4J 15 antibody of the present disclosure;

(b) the Red-E2 antibody of the present disclosure;

(c) Bebtelovimab;

(d) the P2G3 antibody; and

(e) a combination thereof.

Table 9: VH amino acid sequences for P2G3

Table 10: VL amino acid sequences for P2G3

Table 11: Heavy chain CDR sequences for P2G3

Table 12: Light chain CDR sequences for P2G3

[0293] Pharmaceutical compositions of an antibody as described herein are prepared by mixing such antibody having the desired degree of purity with one or more optional pharmaceutically acceptable carriers {Remington's Pharmaceutical Sciences 16th edition, Osol, A. Ed. (1980)), in the form of lyophilized compositions or aqueous solutions. Pharmaceutically acceptable carriers are generally nontoxic to recipients at the dosages and concentrations employed, and include, but are not limited to: buffers such as phosphate, citrate, and other organic acids; antioxidants including ascorbic acid and methionine; preservatives (such as octadecyldimethylbenzyl ammonium chloride; hexamethonium chloride; benzalkonium chloride; benzethonium chloride; phenol, butyl or benzyl alcohol; alkyl parabens such as methyl or propyl paraben; catechol; resorcinol; cyclohexanol; 3-pentanol; and m-cresol); low molecular weight (less than about 10 residues) polypeptides; proteins, such as serum albumin, gelatin, or immunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone; amino acids such as glycine, glutamine, asparagine, histidine, arginine, or lysine; monosaccharides, disaccharides, and other carbohydrates including glucose, mannose, or dextrins; chelating agents such as EDTA; sugars such as sucrose, mannitol, trehalose or sorbitol; salt-forming counter-ions such as sodium; metal complexes (such as Zn-protein complexes); and/or nonionic surfactants such as polyethylene glycol (PEG). Exemplary pharmaceutically acceptable carriers herein further include insterstitial drug dispersion agents such as soluble neutral-active hyaluronidase glycoproteins (sHASEGP), for example, human soluble PH-20 hyaluronidase glycoproteins, such as rHuPH20 (HYLENEX®, Baxter International, Inc.). In one aspect, a sHASEGP is combined with one or more additional glycosaminoglycanases such as chondroitinases.

[0294] Buffers are used to control the pH in a range which optimizes the therapeutic effectiveness, especially if stability is pH dependent. In some embodiments, buffers are present at concentrations ranging from about 50 mM to about 250 mM. Suitable buffering agents for use with the present disclosure include both organic and inorganic acids and salts thereof, such as citrate, phosphate, succinate, tartrate, fumarate, gluconate, oxalate, lactate, acetate. Additionally, buffers may comprise histidine and trimethylamine salts such as Tris. [0295] Preservatives are added to retard microbial growth, and are typically present in a range from 0.2% - 1.0% (w/v). Suitable preservatives for use with the present disclosure include octadecyldimethylbenzyl ammonium chloride; hexamethonium chloride; benzalkonium halides (such as chloride, bromide, iodide), benzethonium chloride; thimerosal, phenol, butyl or benzyl alcohol; alkyl parabens such as methyl or propyl paraben; catechol; resorcinol; cyclohexanol, 3 -pentanol, and m-cresol.

[0296] Tonicity agents, sometimes known as “stabilizers” are present to adjust or maintain the tonicity of liquid in a composition. When used with large, charged biomolecules such as proteins and antibodies, they are often termed “stabilizers” because they can interact with the charged groups of the amino acid side chains, thereby lessening the potential for inter- and intra-molecular interactions. Tonicity agents can be present in any amount between 0.1% to 25% by weight, for instance, between 1% to 5% by weight, taking into account the relative amounts of the other ingredients. In some embodiments, tonicity agents include polyhydric sugar alcohols. In some embodiments, the polyhydric sugar alcohols are trihydric or higher sugar alcohols, such as glycerin, erythritol, arabitol, xylitol, sorbitol and mannitol.

[0297] Non-ionic surfactants or detergents (also known as “wetting agents”) are present to help solubilize the therapeutic agent as well as to protect the therapeutic protein against agitation- induced aggregation, which also permits the composition to be exposed to shear surface stress without causing denaturation of the active therapeutic protein or antibody. Non-ionic surfactants are present in a range of about 0.05 mg/ml to about 1.0 mg/ml, for instance, about 0.07 mg/ml to about 0.2 mg/ml.

[0298] Suitable non-ionic surfactants include polysorbates (20, 40, 60, 65, 80, etc.), polyoxamers (184, 188, etc.), PLURONIC® polyols, TRITON®, polyoxyethylene sorbitan monoethers (TWEEN®-20, TWEEN®-80, etc.), lauromacrogol 400, polyoxyl 40 stearate, polyoxyethylene hydrogenated castor oil 10, 50 and 60, glycerol monostearate, sucrose fatty acid ester, methyl cellulose and carboxymethyl cellulose. Anionic detergents that can be used include sodium lauryl sulfate, dioctyle sodium sulfo succinate and dioctyl sodium sulfonate. Cationic detergents include benzalkonium chloride or benzethonium chloride.

[0299] The choice of pharmaceutical carrier, excipient or dilutent may be selected with regard to the intended route of administration and standard pharmaceutical practice.

[0300] Pharmaceutical compositions may comprise as - or in addition to - the carrier, excipient or dilutent any suitable binder(s), lubricant(s), suspending agent(s), coating agent(s) or solubilizing agent(s). [0301] There may be different composition requirements dependent on the different delivery systems. By way of example, pharmaceutical compositions useful in the present disclosure may be formulated to be administered using a mini-pump or by a mucosal route, for example, as a nasal spray or aerosol for inhalation or ingestible solution, or parenterally in which the composition is formulated by an injectable form, for delivery, by, for example, an intravenous, intramuscular or subcutaneous route. Alternatively, the composition may be designed to be administered by a number of routes.

[0302] In some embodiments, an antibody composition is a lyophilized antibody composition. In some embodiments, an antibody composition is an aqueous antibody composition. Exemplary lyophilized antibody compositions are described in US Patent No. 6,267,958. Aqueous antibody compositions include those described in US Patent No. 6,171,586 and W02006/044908, the latter compositions including a histidine-acetate buffer.

[0303] The composition herein may also contain one or more additional active ingredients, such as antiviral agents, as necessary for the particular indication being treated. In some embodiments, the one or more additional active ingredients are those with complementary activities that do not adversely affect each other. In some embodiments, the one or more additional active ingredients are antiviral agents. In some embodiments, the antiviral agents are selected from the group consisting of Remdesivir, anti-inflammatory drugs, such as tocilizumab and sarilumab, and antibodies that bind to other SARS-CoV-2 proteins required by SARS-CoV- 2 to infect the cell. For example, Remdesivir may be used which is a broad-spectrum antiviral medication that acts as a ribonucleotide analogue inhibitor of viral RNA polymerase. Once additional antivirals against SARS-CoV-2 are identified, it may be desirable to further provide an antiviral agent that target additional steps in the viral replication cycle or an antibody. The combination of the antibodies described in the present disclosure may also be used in combination with anti-inflammatory drugs, including tocilizumab and sarilumab, that have been reported to help prevent COVID-19 related deaths. Antibodies that bind to other SARS- CoV-2 proteins required by SARS-CoV-2 to infect the cell are also contemplated. In any embodiments herein, an antiviral agent as described herein can be used in a composition with an antibody of the present disclosure. Such as antiviral agents described herein are suitably present in combination in amounts that are effective for the purpose intended.

[0304] Active ingredients may be entrapped in microcapsules prepared, for example, by coacervation techniques or by interfacial polymerization, for example, hydroxymethylcellulose or gelatin-microcapsules and poly-(methylmethacylate) microcapsules, respectively, in colloidal drug delivery systems (for example, liposomes, albumin microspheres, microemulsions, nano-particles and nanocapsules) or in macroemulsions. Such techniques are disclosed in Remington's Pharmaceutical Sciences 16th edition, Osol, A. Ed. (1980).

[0305] Stability of the proteins and antibodies described herein may be enhanced through the use of non-toxic “water-soluble polyvalent metal salts”. Examples include Ca2+, Mg2+, Zn2+, Fe2+, Fe3+, Cu2+, Sn2+, Sn4+, A12+ and A13+. Exemplary anions that can form water soluble salts with the above polyvalent metal cations include those formed from inorganic acids and/or organic acids. Such water-soluble salts are soluble in water (at 20°C) to at least about 20 mg/ml, alternatively at least about 100 mg/ml, alternatively at least about 200 mg/ml.

[0306] Suitable inorganic acids that can be used to form the “water soluble polyvalent metal salts” include hydrochloric, acetic, sulfuric, nitric, thiocyanic and phosphoric acid. Suitable organic acids that can be used include aliphatic carboxylic acid and aromatic acids. Aliphatic acids within this definition may be defined as saturated or unsaturated C2-9 carboxylic acids (such as aliphatic mono-, di- and tri-carboxylic acids). For example, exemplary monocarboxylic acids within this definition include the saturated C2-9 monocarboxylic acids acetic, proprionic, butyric, valeric, caproic, enanthic, caprylic pelargonic and capryonic, and the unsaturated C2- 9 monocarboxylic acids acrylic, propriolic methacrylic, crotonic and isocro tonic acids. Exemplary dicarboxylic acids include the saturated C2-9 dicarboxylic acids malonic, succinic, glutaric, adipic and pimelic, while unsaturated C2-9 dicarboxylic acids include maleic, fumaric, citraconic and mesaconic acids. Exemplary tricarboxylic acids include the saturated C2-9 tricarboxylic acids tricarballylic and 1,2,3-butanetricarboxylic acid. Additionally, the carboxylic acids of this definition may also contain one or two hydroxyl groups to form hydroxy carboxylic acids. Exemplary hydroxy carboxylic acids include glycolic, lactic, glyceric, tartronic, malic, tartaric and citric acid. Aromatic acids within this definition include benzoic and salicylic acid.

[0307] Commonly employed water soluble polyvalent metal salts which may be used to help stabilize the encapsulated polypeptides of the present disclosure include, for example: (1) the inorganic acid metal salts of halides (such as zinc chloride, calcium chloride), sulfates, nitrates, phosphates and thiocyanates; (2) the aliphatic carboxylic acid metal salts (e.g., calcium acetate, zinc acetate, calcium proprionate, zinc glycolate, calcium lactate, zinc lactate and zinc tartrate); and (3) the aromatic carboxylic acid metal salts of benzoates (e.g., zinc benzoate) and salicylates.

[0308] Pharmaceutical compositions of antibodies of the present disclosure can be designed to immediately release an antibody (“immediate-release” formulations), to gradually release the antibodies over an extended period of time (“sustained-release,” “controlled-release,” or “extended-release” formulations), or with alternative release profiles. The additional materials used to prepare a pharmaceutical composition can vary depending on the therapeutic form of the composition (for example whether the system is designed for immediate-release or sustained-, controlled-, or extended-release). In certain variations, a sustained-release composition can further comprise an immediate-release component to quickly deliver a priming dose following drug delivery, as well as a sustained-release component. Thus, sustained-release formulations can be combined with immediate-release formulations to provide a rapid “burst” of drug into the system as well as a longer, gradual release. For example, a core sustained- release formulation may be coated with a highly soluble layer incorporating the drug. Alternatively, a sustained-release formulation and an immediate-release formulation may be included as alternate layers in a tablet or as separate granule types in a capsule. Other combinations of different types of drug formulations can be used to achieve the desired therapeutic plasma profile.

[0309] Suitable examples of sustained-release preparations include semi-permeable matrices of solid hydrophobic polymers containing the antagonist, which matrices are in the form of shaped articles, such as films, or microcapsules. Examples of sustained-release matrices include polyesters, hydrogels (for example, poly(2-hydroxyethyl -methacrylate), or poly(vinylalcohol)), polylactides, copolymers of L-glutamic acid and ethyl-L-glutamate, non-degradable ethylenevinyl acetate, degradable lactic acid-glycolic acid copolymers such as the LUPRON DEPOT™ (injectable microspheres composed of lactic acid-glycolic acid copolymer and leuprolide acetate), and poly-D-(-)-3 -hydroxybutyric acid.

[0310] The compositions to be used for in vivo administration are generally sterile. Sterility may be readily accomplished, for example by filtration through sterile filtration membranes. [0311] The pharmaceutical compositions may be used in any of the methods described herein. [0312] The pharmaceutical composition may be used among those subjects (such as humans) susceptible to infection with SARS-CoV-2 z.e., to prevent or reduce/decrease the onset of SARS-CoV-2 infection.

[0313] The pharmaceutical composition may be used among those subjects (such as humans) already infected with SARS-CoV-2 /.< ., to treat SARS-CoV-2 infection. Such treatment may facilitate clearance of the virus from those subjects who are acutely infected.

Therapeutic Methods and Applications

[0314] Another aspect of the present disclosure provides the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure for use as a pharmaceutical. [0315] Another aspect of the present disclosure provides a method of prophylaxis, treatment and/or attenuation of a SARS-CoV-2 virus infection in a subject, comprising administering to the subject an effective amount of the one or more antibodies, or antigen-binding fragments thereof, of the present disclosure or one or more variants of the present disclosure. In some embodiments, the subject has been diagnosed with a SARS-CoV-2 infection or the subject has to be protected from SARS-CoV-2 virus infection. In some embodiments, the subject does not have a SARS-CoV-2 infection. In some embodiments, treating and/or attenuating the SARS- CoV-2 virus infection comprises reducing viral load.

[0316] In some embodiments, the method described herein may be used in the treatment and/or prevention of SARS-CoV-2. Exemplary SARS-CoV-2 variants include WHO alpha variant, WHO beta variant, WHO gamma variant, WHO delta variant, WHO epsilon variant, WHO Eta variant, WHO iota variant, WHO kappa variant, WHO omicron variant, WHO zeta variant, WHO mu variant, and B.1.617.3.

[0317] In some embodiments, the subject may be a neonate, a juvenile, or an adult. In some embodiments, the subject is human. In some embodiments, the subject is non-human primates (e.g., monkeys, baboons, and chimpanzees), mice, rats, bovines, horses, household cats, tigers and other large cats, dogs, pigs, rabbits, goats, deer, sheep, ferrets, gerbils, guinea pigs, hamsters, bats, and birds (e.g., chickens, turkeys, and ducks). A number of these household pets and farm animals are capable of carrying and transmitting SARS-CoV-2 viruses without themselves getting substantially sick or dying, thereby transmitting the disease to humans. Thus, in some embodiments, these animals are treated not because they are suffering from disease, but rather, because they can transmit virus to humans and cause human disease.

[0318] In some embodiments, the subject is a subject in need of treatment and/or a subject being infected by a SARS-CoV-2 virus. In some embodiments, the subject is a subject that may be predisposed to, susceptible to a SARS-CoV-2-associated disorder, or at risk of developing a SARS-CoV-2-associated disorder, but has not yet been diagnosed with the disorder. In some embodiments, the subject is a subject that should be protected from a SARS-CoV-2 virus infection. In some embodiments, the subject is immunocompromised.

[0319] Immunocompromised subjects include subjects that suffer from an immune deficiency (e.g., a primary or acquired immune deficiency) or autoimmune disease, subjects that have undergone or are currently undergoing treatment with one or more immunosuppressive drugs (e.g., chemotherapy, glucocorticoids, protease inhibitors, immune cell depleting monoclonal antibodies, etc.), subjects that have recently received an organ transplant or hematopoietic stem cell transplant, subjects that have received a CAR-T therapy, and subjects that have undergone or are currently undergoing radiation treatment. Immunosuppressive drugs are known to those in the art. See e.g., Hussain Y, Khan H. Immunosuppressive Drugs. Encyclopedia of Infection and Immunity. 2022:726-40. Vaccines, including vaccines against SARS-CoV-2 infections, are less effective in immunocompromised subjects. Furthermore, some immunocompromised subjects may not be able to receive a SARS-CoV-2 vaccine. The antibodies and antigen-binding fragments thereof provided herein therefore provide a therapeutic option for subjects who cannot receive a SARS-CoV-2 vaccine or who demonstrate reduced efficacy of a SARS-CoV- 2 vaccine.

[0320] In some embodiments, treating refers to the treatment of a disease in a mammal, e.g., in a human, including (a) inhibiting the disease, /.< ., arresting disease development or preventing disease progression; (b) relieving the disease, /.< ., causing regression of the disease state or relieving one or more symptoms of the disease; and (c) curing the disease, /.< ., remission of one or more disease symptoms. In some embodiments, treatment results in an improvement or remediation of the symptoms of the disease. In some embodiments, treatment may refer to a short-term (e.g., temporary and/or acute) and/or a long-term (e.g., sustained) improvement or remediation in one or more disease symptoms. In some embodiments, the improvement is an observable or measurable improvement. In some embodiments, the improvement is an improvement in the general feeling of well-being of the subject. In some embodiments, administration of the pharmaceutical compositions disclosed herein may reduce one or more symptoms of the SARS-COV-2 infection, including but not limited to, death, incidence of emphysema, incidence of pneumonia, shortness of breath, racing heart, fever, cough, sore throat, congestion, muscle or body aches, headaches, fatigue, vomiting, diarrhea, loss of taste or smell, cognitive issues like “brain fog”, memory or attention problems, and Postural Orthostatic Tachycardia Syndrome (POTS).

[0321] In some embodiments of the present disclosure, the method of prophylaxis, treatment and/or attenuation of a SARS-CoV-2 virus infection in a subject further comprises administering an antiviral agent. In some embodiments, the antiviral compound comprises: a nucleoside analog, a peptoid, an oligopeptide, a polypeptide, a protease inhibitor, a 3C-like protease inhibitor, a papain-like protease inhibitor, or an inhibitor of an RNA dependent RNA polymerase. In some embodiments, the antiviral compound is selected from: acyclovir, gancyclovir, vidarabine, foscamet, cidofovir, amantadine, ribavirin, trifluorothymidine, zidovudine, didanosine, zalcitabine, and an interferon, and preferably wherein the interferon is an interferon-a or an interferon-p. [0322] In some embodiments, the antiviral agent is selected from the group consisting of a viral protease inhibitor, a viral polymerase inhibitor, an NS5A inhibitor, an interferon, a second antibody, and a combination thereof. In some embodiments, the antiviral agent is selected from the group consisting of Remdesivir, anti-inflammatory drugs, such as tocilizumab and sarilumab, and antibodies that bind to other SARS-CoV-2 proteins required by SARS-CoV-2 to infect the cell. In some embodiments, the antiviral agent is an antibody as described herein. In some embodiments, the antiviral agent is Remdesivir. In some embodiments, the antiviral agent is anti-inflammatory drug. In some embodiments, the anti-inflammatory drug is tocilizumab and/or sarilumab,

[0323] In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure is administered in combination with, sequential to, concurrently with, consecutively with, rotationally with, or intermittently with an antiviral agent (such as a viral RNA polymerase inhibitor) or anti-inflammatory drug (such as an anti-IL-6 antibody). In some embodiments, the administration of the combination of an antibody, or an antigen-binding fragment thereof, of the present disclosure or a variant of the present disclosure and an antiviral agent and/or anti-inflammatory agent ameliorates one or more symptoms of SARS-CoV-2, reduces and/or suppresses viral titer and/or viral load, and/or prevents SARS-CoV-2, and/or achieves a sustained virologic response more than treatment with the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure or the antiviral agent alone. In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure and the antiviral agent and/or anti-inflammatory agent are provided in separate dosage forms. In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure and the antiviral agent are provided in the same dosage form.

[0324] Thus, in a further aspect the present disclosure provides a method of prophylaxis, treatment and/or attenuation of a SARS-CoV-2 virus infection, comprising the use of the one or more antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure or the pharmaceutical composition of the present disclosure. Suitably, an effective amount of the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure or the pharmaceutical composition of the present disclosure is administered to the subject. In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure or the pharmaceutical composition of the present disclosure is administered in a therapeutic effective amount to effect beneficial clinical results, including, but not limited to anti-SARS-CoV-2 SARS-CoV-2 and/or ameliorating one or more symptoms of SARS-CoV-2 infections or aspects of SARS-CoV-2 infection. In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure or the pharmaceutical composition of the present disclosure is administered in a therapeutic effective amount to reduce viral titer and/or viral load of SARS-CoV-2. In some embodiments, the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure or the pharmaceutical composition of the present disclosure is administered in a therapeutic effective amount to achieve a sustained virologic response. As used herein, the term “sustained virologic response” refers to the absence of detectable viremia during certain period of time, such as twelve weeks, after stopping anti- SARS-CoV-2 treatment.

[0325] There is also provided the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure or the pharmaceutical composition of the present disclosure for use in the method of prophylaxis, treatment and/or attenuation of a SARS-CoV-2 virus infection in a subject, wherein the method comprises administering to the subject an effective amount of the one or more antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure or the pharmaceutical composition of the present disclosure.

[0326] There is also provided the use of the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure or the pharmaceutical composition of the present disclosure in the manufacture of a composition for the prophylaxis, treatment and/or attenuation of a SARS-CoV-2 virus infection in a subject. In some embodiments, the prophylaxis, treatment and/or attenuation of a SARS-CoV-2 virus infection in a subject comprises administering to the subject an effective amount of the one or more antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure.

[0327] The antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure or a pharmaceutical composition comprising same are useful in reducing, eliminating, or inhibiting SARS-CoV-2 infection and can be used for treating any pathological condition that is characterized, at least in part, by SARS-CoV-2 infection. The antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure and/or the pharmaceutical composition of the present disclosure can be used for treating a SARS-CoV-2 infection. The antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure and/or the pharmaceutical composition of the present disclosure can also be used in prophylaxis and/or methods for preventing a SARS-CoV-2 infection. For example the antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure and/or the pharmaceutical composition of the present disclosure is administered prophylactically.

[0328] Overall, the inventors have developed some of the most potent antibodies against the SARS-CoV-2 virus with several of the identified antibodies binding distinct, non-overlapping epitopes on the SARS-CoV-2 RBD. As such, monotherapy or combination therapy of antibodies could be used in both prophylactic and therapeutic treatments to combat SARS-CoV- 2 viral infection. Thus in some embodiments of prophylaxis, treatment and/or attenuation of a SARS-CoV-2 virus infection of the present disclosure, a combination of one, two or more antibodies, or antigen-binding fragments thereof, of the present disclosure can be administered to the subject.

[0329] In one aspect, the antibodies or antigen-binding fragments thereof, provided in the present disclosure are used as a monotherapy. In one aspect, the antibodies or antigen-binding fragments thereof, provided in the present disclosure are used in combination therapy. In some embodiments, the combinations are combinations of

(a) the antibody Red-E2 of the present disclosure is administered in combination with one or more antibodies of the present disclosure selected from the group consisting of P4J15, P5-I14, Red-Al and P1N04.

(b) the antibody P5-I14 of the present disclosure is administered in combination with one or more antibodies of the present disclosure selected from the group consisting of P4J15, Red-E2, Red-Al and P1N04.

(c) the antibody P4J 15 of the present disclosure is administered in combination with one or more antibodies of the present disclosure selected from the group consisting of P5-I14, Red-E2, Red-Al and P1N04.

(d) the antibody Red-E2 of the present disclosure is administered in combination with the antibody P4J15 of the present disclosure or the antibody P5-I14 of the present disclosure.

[0330] In some embodiments, the combination is the combination of at least one first antibody of the present disclosure selected from the group consisting of Red-E2, P4J15 and/or P5-I14 and at least one second antibody selected from P2G3 antibody and/or Bebtelovimab. [0331] In some embodiments of prophylaxis, treatment, and/or attenuation of a SARS-CoV-2 virus infection in a subject, the antibody Red-E2 of the present disclosure is administered in combination with one or more antibodies of the present disclosure selected from P4J 15, P5-I14, Red-Al and P1N04. In some embodiments of prophylaxis, treatment, and/or attenuation of a SARS-CoV-2 virus infection in a subject, the antibody P4J15 of the present disclosure is administered in combination with one or more antibodies of the present disclosure selected from Red-E2, P5-I14, Red-Al and P1N04. In some embodiments of prophylaxis, treatment, and/or attenuation of a SARS-CoV-2 virus infection in a subject, the antibody P5-I14 of the present disclosure is administered in combination with one or more antibodies of the present disclosure selected from P4J15, Red-E2, Red-Al and P1N04.

[0332] In some embodiments of prophylaxis, treatment, and/or attenuation of a SARS-CoV-2 virus infection in a subject, the two or more additional antibodies are administered as part of the same composition.

[0333] In some embodiments of prophylaxis, treatment, and/or attenuation of a SARS-CoV-2 virus infection in a subject, the two or more additional antibodies are administered as separate compositions.

[0334] In some embodiments of prophylaxis, treatment, and/or attenuation of a SARS-CoV-2 virus infection in a subject, the two or more additional antibodies are administered sequentially or simultaneously.

[0335] In some embodiments, the one or more additional antibodies are selected from the group consisting of

(a) the P4J 15 antibody of the present disclosure;

(b) the P5-I14 antibody of the present disclosure;

(c) Bebtelovimab;

(d) the P2G3 antibody; and

(e) a combination thereof.

[0336] In some embodiments of prophylaxis, treatment, and/or attenuation of a SARS-CoV-2 virus infection in a subject, the first antibody selected from the Red-E2, P5-I14, or P4J15 antibody of the present disclosure is administered in combination with the second or more antibodies selected from the group consisting of

(a) the Red-E2 antibody of the present disclosure;

(b) the P4J 15 antibody of the present disclosure; (c) the P5-I14 antibody of the present disclosure;

(d) Bebtelovimab;

(e) the P2G3 antibody; and

(f) a combination thereof.

[0337] In some embodiments, the first antibody and the second or more antibodies are administered as part of the same composition. In some embodiments, the first antibody and the second or more antibodies are administered as separate compositions. In further embodiments, the first antibody and the second or more antibodies are administered sequentially or simultaneously.

[0338] In the combination therapy (combined administration) of the present disclosure, the antibodies of the present disclosure are co-administered simultaneously, for example in a combined unit dose (e.g., providing simultaneous delivery). In the combination therapy (combined administration) of the present disclosure, the antibodies of the present disclosure can also be co-administered separately or sequentially at a specified time interval, such as, but not limited to, an interval of minutes, hours, days, weeks or months. In some embodiments, the antibodies of the present disclosure for the combination therapy may be administered essentially simultaneously, for example two unit dosages administered at the same time, or a combined unit dosage of the two or more antibodies. In some embodiments, the antibodies of the present disclosure for combination therapy may be delivered in separate unit dosages. The antibodies of the present disclosure for the combination therapy may be administered in any order, or as one or more preparations that includes two or more antibodies. In some embodiments, at least one administration of one antibody may be made within minutes, one, two, three, or four hours, or even within one or two days of the other antibody. In some embodiments, combination therapy of the present disclosure provides anti-SARS-CoV-2 the SARS-CoV-2 virus through binding of antibodies to different epitopes which has the potential effect of greater neutralization potency, reduced chance of developing viruses with mutations that confer resistance and greater breadth in anti-SARS-CoV-2 viruses with polymorphism in the general population.

[0339] In some embodiments, the methods of attenuation of a SARS-CoV-2 virus infection in a subject, such as reduction of incidence of, reduction duration of, reduction or lessen severity of, typically refers to attenuation of one or more symptoms of SARS-CoV-2 infection. Typically, the symptoms of SARS-CoV-2 include fever, cough, shortness of breath and myalgia or fatigue. [0340] In some embodiments, the methods of the present disclosure suppress or reduce viral titer. “Viral titer” is known in the art and indicates the amount of virus in a given biological sample.

[0341] In some embodiments, the methods of the present disclosure suppress or reduce viremia. “Viremia” is known in the art as the presence of virus in blood, serum, nasopharyngeal and/or nasal swabs, anal swabs, bronchoalveolar lavage, cerebrospinal fluid, nasal-throat swab, throat swab, sputum, a cell, or tissue (such as liver tissue from a liver biopsy).

[0342] n some embodiments, the methods of the present disclosure suppress or reduce viral load. “Viral load” refers to the amount of SARS-CoV-2 virus in a person's nasopharyngeal swabs or other relevant samples. The results of a SARS-CoV-2 viral load test are usually expressed as RNA copies/mL. A subject with a SARS-CoV-2 viral load of >1 million copies/mL or more is considered to have a high viral load. Amount of virus (such as viral titer or viral load) are indicated by various measurements, including, but not limited to amount of viral nucleic acid, the presence of viral particles, replicating units (RU), plaque forming units (PFU). Amount of virus such as high viral load, low viral load or undetectable viral load can be defined according to a clinical acceptable parameter established by the person skilled in the art. In some embodiments, an undetectable viral load is defined by the limit of the assay for detecting SARS-CoV-2. Generally, for fluid samples such as blood and urine, amount of virus is determined per unit fluid, such as milliliters. For solid samples, such as tissue samples, amount of virus is determined per weight unit, such as grams. Methods for determining amount of virus are known in the art and are also described herein. In some embodiments, the methods described herein result in a sustained virologic response for at least 12 weeks after stopping the treatment.

[0343] The term “SARS-CoV-2-associated diseases” or “SARS-CoV-2-associated disorders” or “COVID-19 patients” as used herein, refers to an infection with SARS-CoV-2 or a disease or disorder that is associated with SARS-CoV-2 infection such as respiratory distress. This disease can lead to one or more of the following symptoms that include fever, dry cough, tiredness, aches and pains sore throat, diarrhea, conjunctivitis, headache, loss of taste or smell, a rash on skin, or discolouration of fingers or toes. More serious symptoms include difficulty breathing or shortness of breath chest pain or pressure, and loss of speech or movement. Patients that experience acute respiratory distress syndrome due to COVID-19 will warrant intubation and mechanical ventilation. In severe cases, progression of the disease can lead to long-term health issues or death. Accordingly, in some embodiments, an antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure and/or the pharmaceutical composition of the present disclosure prevents development of a SARS-CoV- 2-associated disease.

[0344] The antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure and/or the pharmaceutical composition of the present disclosure can also be used in methods for preventing a SARS-CoV-2 infection, z.e., in prophylaxis. In some embodiments, the antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure and/or the pharmaceutical composition of the present disclosure are useful in methods of preventing an acute SARS-CoV- 2 infection. In some embodiments, the antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure and/or the pharmaceutical composition of the present disclosure can be used in methods for preventing a SARS-CoV-2 infection in a subject susceptible to infection with SARS-CoV-2. In some embodiments, the antibodies, or antigen-binding fragments thereof, of the present disclosure or the variant of the present disclosure and/or the pharmaceutical composition of the present disclosure can also be used in methods for preventing a SARS-CoV-2 infection in a subject exposed to or potentially exposed to SARS-CoV-2. “Exposure” to SARS-CoV-2 denotes an encounter or potential encounter with SARS-CoV-2 which could result in a SARS-CoV-2 infection. Generally, an exposed subject is a subject that has been exposed to SARS-CoV-2 by a route by which SARS- CoV-2 can be transmitted. In some embodiments, the subject has been exposed to or potentially exposed to a subject which may or may not be infected with SARS-CoV-2 (z.e., SARS-CoV-2 infection status of the subject is unknown). SARS-CoV-2 is often transmitted by air and contact. [0345] In a further aspect, the present disclosure provides for the use of an antibody, or antigenbinding fragment thereof, of the present disclosure or the variant of the present disclosure in the manufacture or preparation of a medicament. In some embodiments, the medicament is for treatment of SARS-CoV-2 infection. In some embodiments, a medicament comprising one or more antibodies, or antigen-binding fragments thereof, of the present disclosure or one or more variants of the present disclosure for use in a method of treating SARS-CoV-2 infection comprises administering to an individual having a SARS-CoV-2 infection an effective amount of the medicament comprising one or more antibodies, or antigen-binding fragments thereof, of the present disclosure or one or more variants of the present disclosure. In one such embodiment, the method further comprises administering to the individual an effective amount of at least one additional antiviral agent, such as agent described herein. In some embodiments, the present disclosure provides for the use of an antibody, or antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure in combination with an antiviral agent described herein in the manufacture or preparation of a medicament.

[0346] The antibody/ies may be administered, for example, in the form of immune serum or be a purified recombinant or monoclonal antibody. Methods of producing sera or monoclonal antibodies with the desired specificity are routine and well-known to those skilled in the art.

[0347] The antibodies, or antigen-binding fragments thereof, of the present disclosure or the variants of the present disclosure can be administered to a subject in accord with known methods and any suitable means, including parenteral, intrapulmonary, and intranasal, and, if desired for local treatment, intralesional administration. Parenteral infusions include intramuscular, intravenous, intraarterial, intraperitoneal, or subcutaneous administration. Dosing can be by any suitable route, for example by injections, such as intravenous or subcutaneous injections, depending in part on whether the administration is brief or chronic. Various dosing schedules including but not limited to single or multiple administrations over various time-points, bolus administration, and pulse infusion are contemplated herein., such as by intravenous administration, for example as a bolus or by continuous infusion over a period of time, by subcutaneous, intramuscular, intraperitoneal, intracerobrospinal, intra-articular, intrasynovial, intrathecal, or inhalation routes, generally by intravenous or subcutaneous administration.

[0348] Suitably, a passive immunization regime may conveniently comprise administration of the antibody, or an antigen-binding fragment thereof, of the present disclosure or the variant of the present disclosure and/or administration of antibody in combination with other antiviral agents. The active or passive immunization methods of the present disclosure should allow for the protection or treatment of individuals against infection with viruses of SARS-CoV-2 type. [0349] The present disclosure discloses some of the most potent antibodies identified to date. They are ideal candidate to be used in passive immunization for the prophylactic protection of uninfected individuals at risk of infection with the SARS-CoV-2 virus. The antibodies disclosed herein could also be used in combination with other anti- SARS-CoV-2 antibodies to have a greater antiviral potency and breadth in neutralizing viruses with mutations. Beyond prophylactic protection, the antibodies described herein can provide therapeutic benefit to: 1) individuals recently infected through contact with a SARS-CoV-2 positive individual, 2) COVID-19 patients that mount a weak humoral immune response and 3) COVID-19 patients in general with deteriorating health due to uncontrolled viral infection.

[0350] The antibodies, or antigen-binding fragments thereof, of the present disclosure or the variants of the present disclosure would be formulated, dosed, and administered in a fashion consistent with good medical practice. Factors for consideration in this context include the particular disorder being treated, the particular mammal being treated, the clinical condition of the individual patient, the cause of the disorder, the site of delivery of the agent, the method of administration, the scheduling of administration, and other factors known to medical practitioners. The antibody need not be, but is optionally, formulated with one or more agents currently used to prevent or treat the disorder in question. The effective amount of such other agents depends on the amount of antibody present in the composition, the type of disorder or treatment, and other factors discussed above. These are generally used in the same dosages and with administration routes as described herein, or about from 1 to 99% of the dosages described herein, or in any dosage and by any route that is empirically/clinically determined to be appropriate.

[0351] For the prevention or treatment of disease, the appropriate dosage of an antibody, or antigen-binding fragment thereof, of the present disclosure or a variant of the present disclosure (when used alone or in combination with one or more other additional antiviral agents) will depend on the type of disease to be treated, the type of antibody, the severity and course of the disease, whether the antibody is administered for preventive or therapeutic purposes, previous therapy, the patient's clinical history and response to the antibody, and the discretion of the attending physician. The antibody is suitably administered to the patient at one time or over a series of treatments. Depending on the type and severity of the disease, about 1 pg/kg to 15 mg/kg (for example O. lmg/kg-lOmg/kg) of antibody can be an initial candidate dosage for administration to the patient, whether, for example, by one or more separate administrations, or by continuous infusion. One typical daily dosage might range from about 1 pg/kg to 100 mg/kg or more, depending on the factors mentioned above. For repeated administrations over several days or longer, depending on the condition, the treatment would generally be sustained until a desired suppression of disease symptoms occurs. One exemplary dosage of the antibody would be in the range from about 0.05 mg/kg to about 10 mg/kg. Thus, one or more doses of about 0.5 mg/kg, 2.0 mg/kg, 4.0 mg/kg or 10 mg/kg (or any combination thereof) may be administered to the patient. Such doses may be administered intermittently, such as every week or every three weeks (for example such that the patient receives from about two to about twenty, or for example about two or about six doses of the antibody). An initial higher loading dose, followed by one or more lower doses may be administered.

[0352] Although there are now several vaccines in clinical trials that demonstrate a high level of efficacy, there is still no data indicating the durability of this vaccine induced protection. In addition, it is likely that at-risk individuals that includes the elderly population and immunosuppressed subjects (such as patients undergoing cancer therapy and those that have undergone an organ transplants) will only have a partial or transient protection induced by these vaccines. As such, the antibodies of the present disclosure may be of significant importance to protect individuals that are less able to mount an effective anti-SARS-CoV-2 immune response following vaccination.

[0353] In one aspect, the present disclosure provides methods for inhibiting, treating or preventing SARS-CoV-2 virus infection in a subject comprising administering to the subject an effective amount of an antibody described herein. In some embodiments, an effective amount of an antibody is administered to a subject for inhibiting, treating or preventing SARS-CoV-2 cellular entry in a subject. In some embodiments, an effective amount of an antibody is administered to an individual for inhibiting, treating or preventing SARS-CoV-2 spread in a subject. In some embodiments, an effective amount of an antibody is administered to a subject for inhibiting, treating or preventing a SARS-CoV-2-associated disease in the individual.

[0354] The identified clones are among the most potent antibodies discovered against the SARS-CoV-2 virus. For instance, the P4J15 antibody has EC50 values of 5 to 16 ng/ml in the pseudoviral assay and 2 to 18 ng/ml in the virus-like particles assay against different Omicron subvariants. Several of potent antibodies disclosed herein also bind to non-overlapping epitopes on the viral Spike protein. This provides an antibody combination therapy that would: 1) have a more pronounced neutralizing activity of the virus, 2) neutralize a broader array of circulating viruses with mutations and 3) help to suppress the development of resistant virus that may emerge in an antibody monotherapy.

[0355] Those skilled in the art will appreciate that the present disclosure described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the present disclosure includes all such variations and modifications without departing from the spirit or essential characteristics thereof. The present disclosure also includes all of the steps, features, compositions and compounds referred to or indicated in this specification, individually or collectively, and any and all combinations or any two or more of said steps or features. The present disclosure is therefore to be considered as in all aspects illustrated and not restrictive, the scope of the present disclosure being indicated by the appended claims, and all changes which come within the meaning and range of equivalency are intended to be embraced therein.

[0356] The foregoing description will be more fully understood with reference to the following Examples. Such Examples, are, however, exemplary of methods of practising the present disclosure and are not intended to limit the application and the scope of the present disclosure. FURTHER NUMBERED EMBODIMENTS

[0357] Further numbered embodiments of the present disclosure are provided as follows: [0358] Embodiment 1. An antibody that binds to the Spike protein of a SARS-CoV2 virus, or an antigen-binding fragment thereof, comprising a heavy chain variable region (VH) that comprises a heavy chain CDR1 (HCDR1), a heavy chain CDR2 (HCDR2), and a heavy chain CDR3 (HCDR3); and a light chain variable region (VL) that comprises a light chain CDR1 (LCDR1), a light chain CDR2 (LCDR2), and a light chain CDR3 (LCDR3), wherein: a) the HCDR1, HCDR2, and HCDR3 sequences are as set forth in SEQ ID NO: 9, SEQ ID NO: 10, and SEQ ID NO: 11, respectively; the LCDR1, LCDR2, and LCDR3 sequences are as set forth in SEQ ID NO: 21, SEQ ID NO: 22, and SEQ ID NO: 23, respectively (antibody Red- E2); b) the HCDR1, HCDR2, and HCDR3 sequences are as set forth in SEQ ID NO: 12, SEQ ID NO: 13, and SEQ ID NO: 14, respectively; the LCDR1, LCDR2, and LCDR3 sequences are as set forth in SEQ ID NO: 24, SEQ ID NO: 25, and SEQ ID NO: 26, respectively (antibody Red-Al); c) the HCDR1, HCDR2, and HCDR3 sequences are as set forth in SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 17, respectively; the LCDR1, LCDR2, and LCDR3 sequences are as set forth in SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively (antibody P4J15); d) the HCDR1, HCDR2, and HCDR3 sequences are as set forth in SEQ ID NO: 18, SEQ ID NO: 19, and SEQ ID NO: 20, respectively; the LCDR1, LCDR2, and LCDR3 sequences are as set forth in SEQ ID NO: 30, SEQ ID NO: 31, and SEQ ID NO: 32, respectively (antibody P1N04); e) the HCDR1, HCDR2, and HCDR3 sequences are as set forth in SEQ ID NO: 44, SEQ ID NO: 45, and SEQ ID NO: 46, respectively; the LCDR1, LCDR2, and LCDR3 sequences are as set forth in SEQ ID NO: 47, SEQ ID NO: 48, and SEQ ID NO: 49, respectively (antibody P5-I14).

[0359] Embodiment 2. The antibody, or an antigen-binding fragment thereof of Embodiment 1, wherein the HCDR1, HCDR2, and HCDR3 sequences are as set forth in SEQ ID NO: 9, SEQ ID NO: 10, and SEQ ID NO: 11, respectively; the LCDR1, LCDR2, and LCDR3 sequences are as set forth in SEQ ID NO: 21, SEQ ID NO: 22, and SEQ ID NO: 23, respectively (antibody Red-E2).

[0360] Embodiment s. The antibody, or an antigen-binding fragment thereof of Embodiment 1, wherein the HCDR1, HCDR2, and HCDR3 sequences are as set forth in SEQ ID NO: 44, SEQ ID NO: 45, and SEQ ID NO: 46, respectively; the LCDR1, LCDR2, and LCDR3 sequences are as set forth in SEQ ID NO: 47, SEQ ID NO: 48, and SEQ ID NO: 49, respectively (antibody P5-I14). [0361] Embodiment 4. The antibody, or an antigen-binding fragment thereof of Embodiment 1, wherein the HCDR1, HCDR2, and HCDR3 sequences are as set forth in SEQ ID NO: 15, SEQ ID NO: 16, and SEQ ID NO: 17, respectively; the LCDR1, LCDR2, and LCDR3 sequences are as set forth in SEQ ID NO: 27, SEQ ID NO: 28, and SEQ ID NO: 29, respectively (antibody P4J15).

[0362] Embodiment 5. The antibody, or an antigen-binding fragment thereof of Embodiment 1, wherein the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to an amino acid sequence selected from SEQ ID NOs: 1-4 and 42, and wherein the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to an amino acid sequence selected from SEQ ID NOs: 5-8 and 43.

[0363] Embodiment 6. The antibody, or an antigen-binding fragment thereof of Embodiment 5, wherein: a. the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 1 and the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 5; b. the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 2 and the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 6; c. the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 3 and the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 7; d. the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 4 and the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 8; e. the VH comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 42 and the VL comprises an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 43.

[0364] Embodiment 7. The antibody, or an antigen-binding fragment thereof of Embodiment 1, wherein: a. the VH amino acid sequence comprises or consists of the amino acid sequence of SEQ ID NO: 1 and the VL amino acid sequence comprises or consists of the amino acid sequence of SEQ ID NO: 5; b. the VH amino acid sequence comprises or consists of the amino acid sequence of SEQ ID NO: 2 and the VL amino acid sequence comprises or consists of the amino acid sequence of SEQ ID NO: 6; c. the VH amino acid sequence comprises or consists of the amino acid sequence of SEQ ID NO: 3 and the VL amino acid sequence comprises or consists of the amino acid sequence of SEQ ID NO: 7; d. the VH amino acid sequence comprises or consists of the amino acid sequence of SEQ ID NO: 4 and the VL amino acid sequence comprises or consists of the amino acid sequence of SEQ ID NO: 8; e. the VH amino acid sequence comprises or consists of the amino acid sequence of SEQ ID NO: 42 and the VL amino acid sequence comprises or consists of the amino acid sequence of SEQ ID NO: 43.

[0365] Embodiment 8. An antibody, or an antigen-binding fragment thereof, comprising a VH comprising an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 1, and a VL comprising an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 5 (antibody Red-E2). [0366] Embodiment 9. An antibody, or an antigen-binding fragment thereof, comprising a VH amino acid sequence that comprises or consists of the amino acid sequence of SEQ ID NO: 1, and a VL amino acid sequence that comprises or consists of SEQ ID NO: 5 (antibody Red-E2).

[0367] Embodiment 10. An antibody, or an antigen-binding fragment thereof, comprising a VH comprising an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 42, and a VL comprising an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 43 (antibody P5-I14). [0368] Embodiment 11. An antibody, or an antigen-binding fragment thereof, comprising a VH amino acid sequence that comprises or consists of the amino acid sequence of SEQ ID NO: 42, and a VL amino acid sequence that comprises or consists of SEQ ID NO: 43 (antibody P5-I14).

[0369] Embodiment 12. An antibody, or an antigen-binding fragment thereof, comprising a VH region comprising an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 3, and a VL region comprising an amino acid sequence that is at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the amino acid sequence of SEQ ID NO: 7 (antibody P4J15).

[0370] Embodiment 13. An antibody, or an antigen-binding fragment thereof, comprising a VH amino acid sequence that comprises or consists of the amino acid sequence of SEQ ID NO: 3, and a VL amino acid sequence that comprises or consists of SEQ ID NO: 7 (antibody P4J15).

[0371] Embodiment 14. The antibody, or an antigen-binding fragment thereof, of any one of Embodiments 1-13, wherein the antibody is an isolated monoclonal antibody.

[0372] Embodiment 15. The antibody, or an antigen-binding fragment thereof, of any one of Embodiments 1-14, wherein the antibody is selected from a human antibody, a canine antibody, a chicken antibody, a goat antibody, a mouse antibody, a pig antibody, a rat antibody, a shark antibody, and a camelid antibody.

[0373] Embodiment 16. The antibody, or an antigen-binding fragment thereof, of Embodiment 15, wherein: the antibody is a human antibody selected from a human IgG (including human IgGl, human IgG2, human IgG2a, human IgG2b, human IgG3, and human IgG4), a human IgM, a human IgA (including human IgAl and human IgA2), a human IgD, and a human IgE, the antibody is a canine antibody selected from a canine IgGA, a canine IgGB, a canine IgGC, and a canine IgGD, the antibody is a chicken antibody selected from a chicken IgA, a chicken IgD, a chicken IgE, a chicken IgG, a chicken IgM, and a chicken IgY, the antibody is a goat antibody including a goat IgG, the antibody is a mouse antibody including a mouse IgG.

[0374] Embodiment 17. The antibody, or an antigen-binding fragment thereof, of any one of Embodiments 1-16, wherein the antibody is a mono-specific antibody, a bispecific antibody, a tri-specific antibody, a multi-specific antibody, or a multivalent antibody.

[0375] Embodiment 18. The antibody, or an antigen-binding fragment thereof, of any one of Embodiments 1-17, wherein the antibody is a humanized antibody, a caninized antibody, a chimeric antibody (including a canine-human chimeric antibody, a canine-mouse chimeric antibody, and an antibody comprising a canine Fc), or a CDR-grafted antibody.

[0376] Embodiment 19. The antibody, or an antigen-binding fragment thereof, of any one of Embodiments 1-18, wherein the antigen binding fragment is selected from the group consisting of a Fab, a Fab2, a Fab’ single chain antibody, a Fv, a single chain variable fragment (scFv), and a nanobody.

[0377] Embodiment 20. The antibody, or an antigen-binding fragment thereof, of any one of Embodiments 1-19, further comprising a detectable label fixably attached thereto, wherein the detectable label is selected from the group consisting of fluorescein, DyLight, Cy3, Cy5, FITC, HiLyte Fluor 555, HiLyte Fluor 647, 5-carboxy-2,7-dichlorofluorescein, 5- carboxyfluorescein, 5-FAM, hydroxy tryptamine, 5-hydroxy tryptamine (5-HAT), 6- carboxyfluorescein (6-FAM), FITC, 6-carboxy-l,4-dichloro-2’,7’-dichloro^_,fluorescein (TET), 6-carboxy-l,4-dichloro-2’,4’,5’,7’-tetra^_,chlorofluorescein (HEX), 6-carboxy-4’,5’-dichloro- 2’,7’-dimethoxy^_,fluorescein (6-JOE), an Alexa fluor (Alexa fluor 350, Alexa fluor 405, Alexa fluor 430, Alexa fluor 488, Alexa fluor 500, Alexa fluor 514, Alexa fluor 532, Alexa fluor 546, Alexa fluor 555, Alexa fluor 568, Alexa fluor 594, Alexa fluor 610, Alexa fluor 633, Alexa fluor 635, Alexa fluor 647, Alexa fluor 660, Alexa fluor 680, Alexa fluor 700, Alexa fluor 750), a BODIPY fluorophore (BODIPY 492/515, BODIPY 493/503, BODIPY 500/510, BODIPY 505/515, BODIPY 530/550, BODIPY 542/563, BODIPY 558/568, BODIPY 564/570, BODIPY 576/589, BODIPY 581/591, BODIPY 630/650-X, BODIPY 650/665-X, BODIPY 665/676), FL, FL ATP, Fl-Ceramide, R6G SE, TMR, TMR-X conjugate, TMR-X, SE, TR, TR ATP, TR-X SE, a rhodamine, rhodamine 110, rhodamine 123, rhodamine B, rhodamine B 200, rhodamine BB, rhodamine BG, rhodamine B extra, 5-carboxytetramethylrhodamine (5- TAMRA), 5 GLD, 6-carboxyrhodamine 6G, Lissamine, Lissamine Rhodamine B, Phallicidine, Phalloidine, rhodamine red, Rhod-2, 6-carboxy-X-rhodamine (ROX), carboxy-X-rhodamine (5-ROX), Sulphorhodamine B can C, Sulphorhodamine G Extra, 6- carboxytetramethyHrhodamine (TAMRA), tetramethylrhodamine (TRITC), rhodamine WT, Texas Red, and Texas Red-X.

[0378] Embodiment 21. A pharmaceutical composition comprising one or more antibodies, or antigen-binding fragments thereof, of any one of Embodiments 1-20 and a pharmaceutically acceptable carrier.

[0379] Embodiment 22. The pharmaceutical composition of Embodiment 21, comprising two or more antibodies, wherein the first antibody is the Red-E2 antibody set forth in Embodiment la, Embodiment 2, Embodiment 6a, Embodiment 7a, Embodiment 8 and/or Embodiment 9 and the second or more antibodies are selected from: the P4J15 antibody set forth in Embodiment 1c, Embodiment 4, Embodiment 6c, Embodiment 7c, Embodiment 12 and/or Embodiment 13; the P5-I14 antibody set forth in Embodiment le, Embodiment 3, Embodiment 6e, Embodiment 7e, Embodiment 10 and/or Embodiment 11; Bebtelovimab; the P2G3 antibody; and a combination thereof.

[0380] Embodiment 23. A method for detecting a SARS-CoV-2 virus in a sample, the method comprising contacting the sample with the antibody, or antigen-binding fragment thereof, of any one of Embodiments 1-20 and detecting the antibody in the sample. [0381] Embodiment 24. The method of Embodiment 23, further comprising comparing the amount of the antibody detected in the sample to the amount of the antibody detected in a control sample, wherein increased detection of the antibody in the sample relative to the control sample indicates the presence of the SARS-CoV-2 virus in the test biological sample.

[0382] Embodiment 25. The method of Embodiment 23 or 24, wherein the SARS-CoV-2 virus is selected from wild type SARS-CoV-2 or a variant of SARS-CoV-2 selected from Alpha (B.l.1.7), Beta (B.1.351), Gamma (P.l), Delta (Bl.617.2), and Omicron (B.1.1.529).

[0383] Embodiment 26. The method of any one of Embodiments 23-25, wherein the sample is selected from the group consisting of blood, serum, nasopharyngeal and/or nasal swabs, anal swabs, bronchoalveolar lavage, cerebrospinal fluid, nasal-throat swab, throat swab, sputum, a cell, and tissue.

[0384] Embodiment 27. The antibody, or an antigen-binding fragment thereof, of any one of Embodiments 1-20 for use as a pharmaceutical.

[0385] Embodiment 28. The antibody, or an antigen-binding fragment thereof, of any one of Embodiments 1-20 for use in a method of prophylaxis, treatment, and/or attenuation of a SARS-CoV-2 virus infection in a subject, wherein the method comprises administering to the subject an effective amount of one or more antibodies, or antigen-binding fragments thereof, of any one of Embodiments 1-20.

[0386] Embodiment 29. The antibody, or an antigen-binding fragment thereof, for use according to Embodiment 28, wherein the first antibody selected from the Red-E2 antibody set forth in Embodiment la, Embodiment 2, Embodiment 6a, Embodiment 7a, Embodiment 8 and/or Embodiment 9 or the P5-I14 antibody set forth in Embodiment le, Embodiment 3, Embodiment 6e, Embodiment 7e, Embodiment 10 and/or Embodiment 11 is administered in combination with the second or more antibody selected from the group consisting of the P4J15 antibody set forth in Embodiment 1c, Embodiment 4, Embodiment 6c, Embodiment 7c, Embodiment 12 and/or Embodiment 13; the P5-I14 antibody set forth in Embodiment le, Embodiment 3, Embodiment 6e, Embodiment 7e, Embodiment 10 and/or Embodiment 11; Bebtelovimab; the P2G3 antibody; and a combination thereof.

[0387] Embodiment 30. The antibody, or an antigen-binding fragment thereof, for use according to Embodiment 29, wherein the first antibody and the second or more antibody are administered as part of the same composition.

[0388] Embodiment 31. The antibody, or an antigen-binding fragment thereof, for use according to Embodiment 29, wherein the first antibody and the second or more antibody are administered as separate compositions. [0389] Embodiment 32. The antibody, or an antigen-binding fragment thereof, for use according to Embodiment 29 or 31, wherein the first antibody and the second or more antibody are administered sequentially or simultaneously.

[0390] Embodiment 33. The antibody, or an antigen-binding fragment thereof, for use according to any one of Embodiments 28-32, wherein the subject has been diagnosed with a SARS-CoV-2 infection.

[0391] Embodiment 34. The antibody, or an antigen-binding fragment thereof, for use according to any one of Embodiments 28-32, wherein the subject does not have a SARS-CoV- 2 infection.

[0392] Embodiment 35. The antibody, or an antigen-binding fragment thereof, for use according to any one of Embodiments 28-34, wherein the subject is immunocompromised.

[0393] Embodiment 36. The antibody, or an antigen-binding fragment thereof, for use according to any one of Embodiments 28-33 and 35, wherein treating and/or attenuating the SARS-CoV-2 virus infection comprises reducing viral load.

[0394] Embodiment 37. The antibody, or an antigen-binding fragment thereof, for use according to any one of Embodiments 28-36, further comprising administering an antiviral agent.

[0395] Embodiment 38. An isolated nucleic acid encoding the antibody, or an antigenbinding fragment thereof, of any one of Embodiments 1-19.

[0396] Embodiment 39. A vector comprising a nucleic acid encoding the antibody, or an antigen-binding fragment thereof, of any one of Embodiments 1-19.

[0397] Embodiment 40. The vector of Embodiment 39, wherein the vector is an expression vector.

[0398] Embodiment 41. A host cell comprising a nucleic acid encoding the antibody, or an antigen-binding fragment thereof, of any one of Embodiments 1-19 or comprising the vector of Embodiment 39 or 40.

[0399] Embodiment 42. The host cell of Embodiment 41, wherein the host cell is prokaryotic or eukaryotic.

[0400] Embodiment 43. A method of producing the antibody, or an antigen-binding fragment thereof, of any one of Embodiments 1-19 comprising culturing a host cell comprising a nucleic acid encoding the antibody, or an antigen-binding fragment thereof, of any one of Embodiments 1-19 under a condition suitable for expression of the nucleic acid; and recovering the antibody, or an antigen-binding fragment thereof, produced by the cell. [0401] Embodiment 44. The method of Embodiment 43, further comprising purifying the antibody, or an antigen-binding fragment thereof.

[0402] Embodiment 45. A kit for detecting SARS-CoV-2 virus in a sample, the kit comprising the one or more antibodies, or antigen-binding fragments thereof, of any one of Embodiments 1-20 and instructions for use.

[0403] Embodiment 46. The kit of Embodiment 45 wherein the antibody, or an antigenbinding fragment thereof, of any one of Embodiments 1-20 is in lyophilized form.

EXAMPLES

Example 1: Selection of SARS-CoV-2 infected donors, isolation and selection of anti-SARS- CoV-2 antibodies.

[0404] In order to isolate potent neutralizing antibodies against the SARS-CoV-2 virus, serum samples from COVID-19 patients were screened for the presence of high titers of antibodies able to bind to the SARS-CoV-2 Spike protein and with neutralizing activity in the SARS-CoV- 2 Spike pseudoviral neutralization assay (assay methods described below). In addition to COVID-19 patients, serum samples from >100 donors that were naturally infected with the SARS-CoV-2 virus and vaccinated with a SARS-CoV-2 mRNA vaccine or donors that were vaccinated then became infected with the SARS-COV-2 virus, were also evaluated. This analysis resulted in the identification of three (3) patients with elevated serum levels of neutralizing antibodies including a potent antibody response against the Omicron BA.1 and BA.4 variants.

[0405] In the isolation of antigen specific B cells, freshly isolated blood mononuclear cells from the selected COVID-19 patients were incubated with biotinylated Spike trimer protein, biotinylated RBD protein and a cocktail of fluorescently labeled antibodies for flow cytometry. Spike trimer proteins used in these studies corresponded to either the original 2019-nCoV first identified in Wuhan China, the Beta variant from South Africa (B.1.351), Delta variant from India (B.1.617.2) or the Omicron BA.l variant. Biotinylated proteins were stained with Streptavidin-PE and SARS-CoV-2 antigen specific B memory cells were detected and sorted separately according to Spike/RBD expression (/.< ., PE fluorescence), IgG (i.e., IgD and IgM negative cells), CD 19 and CD27 expression. Individual cells were seeded in separate plates as single cell micro-cultures on human feeder cells (i.e., CD40L expressing 3T3 cells) in the presence of Epstein-Barr Virus (EBV) (which also stimulate poly clonally memory B cells) and a cocktail composed TLR9 agonist CpG-2006, IL-2 (1000 lU/ml), IL-6 (10 ng/ml), IL-21 (10 ng/ml), and anti-BCR goat antibodies (BCR triggering).

[0406] Supernatants from the day 14 immortalized B cell cultures were then tested for binding to the Spike trimer protein in the Luminex bead-based assay. The different recombinant proteins used in binding assays were produced by transient transfection of either CHO or 293 T mammalian cell lines and enriched to >90% purity from the cell surface supernatants as described in Fenwick et al (J Virol. 2020 Nov 3: JVI.01828-20. doi: 10.1128/JVI.01828-20). In performing the antibody binding assay, Spike coupled beads are diluted 1/100 in PBS with 50 pl added to each well of a Bio-Plex Pro 96-well Flat Bottom Plates (Bio-Rad). Following bead washing with PBS on a magnetic plate washer (MAG2x program), 50 pl of individual antibodies at different dilution concentrations in PBS were added to the plate wells. Plates were sealed with adhesive film, protected from light and agitated at 500 rpm for 30 minutes on a plate shaker. Beads were then washed on the magnetic plate washer and anti-human IgG-PE secondary antibody (ThermoFisher) was added at a 1/100 dilution with 50pl per well. Plates were agitated for 45 minutes, and then washed on the magnetic plate washer. Beads resuspended in 80 pl of reading buffer were agitated 5 minutes at 700 rpm on the plate shaker then read directly on a Luminex FLEXMAP 3D plate reader (ThermoFisher). Wells with supernatant contained antibody with elevated binding properties to Spike were further profiled for binding to the SARS-CoV-2 SI protein and RBD domain, and for neutralizing activity at different dilutions in the SARS-CoV-2 Spike pseudotyped lentivirus neutralization assay. Antibodies in the individual well supernatants were evaluated for binding to either the RBD domain from the 2019-nCoV or a panel of Spike proteins (2019-nCoV, Delta, Delta with K444T substitution, Omicron BA.l, Omicron BA2, Omicron BA.4/BA.5 and SARS1). This level and depth of characterization at this early step in the antibody discovery pipeline is not standard in the field and contributed to our unexpected finding of the select few B cell clones with the desired broad binding properties out of the >10’000 B cell supernatants evaluated. Neutralization activity determined in a 384-well plate assay where antibody supernatant dilutions were mixed with the SARS-CoV-2 Spike pseudotyped lentivirus for 1 hour at 37° C (5% CO2) before the addition to 293T ACE-2 cells. These were incubated for a further 72 h, after which cells were lysed and treated with the ONE-Step™ Luciferase Assay System (LabForce) and luciferase activity detected by reading the plates on a Synergy microplate luminometer (BioTek). The percent neutralization value of each antibody supernatant samples performed at two serum dilutions was then evaluated along with the Spike binding data to select the best antibodies for cloning. [0407] B cells that produced antibody supernatants with the strongest neutralizing activity and those that had broad binding properties for the different Spike protein variants tested were collected with heavy and light chain antibody sequences cloned. Cloning was accomplished by standard molecular biology methods where cellular RNA was extracted using the NucleoSpin RNA XS kit (Life System Designs), reverse transcription with SMARTScribe™ Reverse Transcriptase kit (Takeda Bio Europe), PCR amplification with Platinum™ Taq DNA Polymerase High Fidelity (Life Technologies Europe) and cloning of DNA inserts corresponding to the heavy and light chain variable regions into a TA cloning vector. The resulting nucleotide sequences and corresponding amino acid sequences of the variable regions as well as the amino acid sequences of the complementarity determining regions (CDRs) ascertained are provided in the present disclosure (see Tables 1 and 2). These sequences correspond to the neutralizing antibodies termed Red-E2, P4J15, P5-I14, Red-Al, P1N04 that are IgGl-type fully human monoclonal antibody.

Example 2: Production of anti-SARS-CoV-2 antibodies

[0408] The heavy chain and kappa or lambda light chain sequences identified from the antigen specific B cells producing neutralizing antibody were cloned by standard molecular biology into IgG mammalian expression vectors (e.g., pFUSE expression vectors). Plasmids encoding the anti-SARS-CoV-2 antibodies with CDRs listed in Tables 1 and 2 were co-transfected into the CHO Express mammalian cell line. After incubation of transiently transfected cells for 7 days, the full-length IgGl -based antibodies were purified from the cell culture medium using standard techniques (e.g., a full-length IgGl -based antibody may be purified using a recombinant protein-A column (GE-Healthcare)). This protocol is described in further detail in Fenwick et al J Exp Med. 2019 Jul 1 ;216(7): 1525-1541. doi: 10.1084/jem.20182359.

Example 3: Binding characterization of anti-SARS-CoV-2 antibodies

[0409] Binding affinities of the purified anti-SARS-CoV-2 antibodies listed in Fig.19 were evaluated for recombinant expressed Spike trimer proteins in Luminex binding assays. The Red-E2, P4J15, P5-I14, Red-Al and P1N04 antibodies exhibited the highest binding affinities and breadth in binding the different SARS-CoV-2 variants (/.< ., the ancestral 2019-nCoV, Alpha, Beta, Delta, Omicron BA.l, BA.2 and BA.4/BA.5) with binding IC50 values less than 2.3, 4.8, 12, 2.7 and 3.6 ng/ml, respectively (Fig.19 and Figs. 1A-1H). These affinities are similar to or improved relative to a panel of the current most potent antibodies against the SARS-CoV-2 variants. As a note, binding of all antibodies were shown to be specific for SARS- CoV-2 as none bound with significant affinity to the Spike trimer from the 2003 SARS1 outbreak. Importantly, Red-E2, P4J15 P5-I14, and Red-Al bound with equivalent affinity to the Spike Delta variant with the K444T substitution (IC50 values <7.2 ng/ml), exhibiting significantly better binding affinity compared to the class 3 antibodies P2G3, Ly- Covl4014/Bebtelovimab and AZD1061/Cilgavimab.

[0410] The ability to block the interaction between the Spike trimer and the ACE-2 receptor was next evaluated in a Luminex competitive binding assay. To perform the Spike trimer /ACE- 2 blocking assay, Spike beads were incubated with different dilutions of the test antibodies with agitation at 500 rpm for 30 minutes on a plate shaker. The ACE-2 mouse Fc fusion protein (Creative Biomart) was then added to each well at a final concentration of 1 pg/ml, re-sealed with adhesive film, protected from light and agitated at 500 rpm for 60 minutes on a plate shaker. Beads were then washed on the magnetic plate washer and anti-mouse IgG-PE secondary antibody (OneLambda ThermoFisher) was added at a 1/100 dilution with 50pl per well. Following a 30-minute incubation with agitation, beads were washed then read directly on a Luminex FLEXMAP 3D plate reader (ThermoFisher). MFI for each of the beads alone wells were averaged and used as the 100% binding signal for the ACE-2 receptor to the bead coupled Spike trimer.

[0411] Blockade of the Spike-ACE2 interaction is one important mechanism by which antibodies exert potent neutralization of the SARS-CoV-2 virus by preventing viral entry into ACE2 expressing target cells. The Luminex based Spike- ACE2 biochemical assay used in these experiments is a valuable tool to assess antibody activity against a panel of Spike trimer proteins from different viral variants and with different amino acid substitutions. Against the panel of Spike protein tested, Red-E2, P4J15 and P5-I14 exhibit the most potent and broad activity in blocking ACE2 binding with IC50 values <44, <114 and <126 ng/ml, respectively (Fig. 20 and Figs. 2A-2H). By comparison, the best-in-class benchmark antibodies used for comparison and tested in parallel exhibited IC50 values that were from 514 to >10000 ng/ml against select variants and mutants. Although Red-Aland P1N04 bind with high affinity to most of the Spike proteins evaluated (Fig. 19), it only weakly blocked the Spike-ACE2 interaction with select variants and did not reach an ACE2 blocking Imax of 100%.

Example 4: Neutralization characteristics of anti-SARS-CoV-2 antibodies

[0412] Antibodies discovered with binding properties for the different Spike protein variants were further characterized in neutralization assays using the SARS-CoV-2 Spike pseudotyped lentivirus. The Spike pseudotyped lentivirus encoding the Luciferase reporter gene was incubated in a concentration response with each of the antibodies for 1 hour and the mixture was then added to 293T cells stably expressing the ACE-2 receptor in a 96-well plate. Following a 72-hour incubation at 37 °C with 5% CO2, cells infected with virus produced elevated levels of luciferase while the presence of neutralizing antibody inhibited viral infection and luciferase production. The inhibition EC50 values for each of the antibodies (Fig. 21) corresponds with the inhibition curves in Figs. 3A-3D. In this assay, potent neutralization of Omicron BA.l and BA.4 is shown with EC50 values of 5 & 6 ng/ml for Red-E2, 15 & 6 ng/ml for P4J15 and 4 & 3 ng/ml for P5-I14, respectively. These activities are superior to those shown for P5C3 and AZD1061/Cilgavimab and equivalent to or slightly less potent than the P2G3 and Bebtelovimab Class 3 antibodies. Red-E2 exhibits EC50 values of 33 & 43 against Spike D614G and Delta variants while P4J15 shows EC50 values of 64 & 85 ng/ml and P5-I15 shows EC50 values of 63 & 64 ng/ml, respectively. These values represent a moderate potency range although with reduced activity compared to P2G3, P5C3, Bebtelovimab and AZD1061/Cilgavimab against these past variants that are no longer in circulation. Consistent with the neutralizing activity against the BA.l and BA.4 Omicron variants, Red-E2 also shows potent neutralization of the Omicron BA.2.12.1 variant with an EC50 of 3 ng/ml (Fig. 21). Neutralization activities of Red- A1 and P1N04 were lower relative to the panel of potent benchmark antibodies testes, however in acting by a mechanism that is distinct from the Spike-ACE2 interaction; these antibodies may bind to alternate epitopes that are highly conserved.

[0413] As a further confirmation of the unique binding epitope and neutralizing properties of the present disclosure, Red-E2, P5-I14, P4J15 and Red-Al were evaluated for neutralizing potency against lentiviruses that were pseudotyped with Omicron BA.4 Spike encoding the K444T and V445A substitutions that confer resistance to Class 3 neutralizing antibodies including Bebtelovimab. Red-E2 and P4J15 exhibited highly potent activity against the Spike K444T and V445A pseudoviruses with EC50 values of <3 and 4 ng/ml, respectively (Fig. 22) and P5-I14 showed an EC50 of 3 ng/ml against the Spike K444T pseudovirus. By comparison, Bebtelovimab tested in parallel showed a >200-fold and > 120-fold loss in potency against the Spike K444T and V445A pseudotyped viruses, respectively.

[0414] In recent months, Omicron BA.4 and BA.5 virus has acquired the R346T mutation in several sub-lineages including BA.4.6, which has provided the virus with improved transmissibility and resistance to certain classes of neutralizing antibodies. As an example, Evusheld is reported to be completely inactive against the BA.4.6 virus owing to the R346T substitution (https://doi.org/10.1101/2022.09.15.5Q7787 ). In lentivirus assays pseudotyped with Omicron BA.4 Spike encoding the R346T mutation, Red-E2, P5-14 and P4J15 all show no loss in potency relative to the unmodified Omicron BA.4 Spike with EC50 values <3 ng/ml. Neutralization assays performed with Red-Al showed that this antibody had moderate potency (EC50 values of 76 to 217 ng/ml) against lentiviruses pseudotyped with Omicron BA.4 Spike encoding the K444T, V445A and R346T substitutions.

Example 5: Neutralization characteristics of select anti-SARS-CoV-2 antibodies against SARS-CoV-2 variants in a live virus cytopathic effect assay

[0415] Antiviral potency of selected antibodies was evaluated in the live virus cytopathic effect assay (CPE) performed with Omicron BA.l, BA.2 and BA.4 SARS-CoV-2 viruses (Fig. 23). In these tests, Red-E2 and P4J15 are the most potent neutralizing antibody discovered with a broad potency in neutralizing Omicron BA.1, BA.2 and BA.4 variants with ECso value ranging from 5 to 10 ng/ml. By comparison, Evusheld, the dual antibody combination of Cilgabvimab and Tixagevimab, show EC50s from 40 to 290 ng/ml. The class 3 antibodies P2G3 and Bebtelovimab both have potent activity against Omicron variants (EC50 from 2 to 12 ng/ml) while P5C3, the only Class 1 antibody advanced to the clinic with significant potency against Omicron variants exhibits EC50 values >139 ng/ml (Figs. 23 and 4).

Example 6: Comparative competitive binding studies of different antibodies to recombinant SARS-CoV-2 RBD protein

[0416] Competitive binding studies allowed for the mapping of competitive, partially competitive and non-overlapping binding of different anti-SARS-CoV-2 antibodies to the RBD protein. The competitive binding assay was performed in a similar manner to the Spike/ ACE-2 assay except that 20 pg/ml of the indicated competitor antibody was incubated with RBD coupled beads for 30 minutes followed by the addition of 0.5 to 2 pg/ml of the indicated biotinylated antibodies. Beads were washed and the RBD bound biotinylated antibody was detected with PE labeled Streptavidin (Sigma). Direct completion between the two antibodies tested resulted in low level PE fluorescence associated with the RBD beads while noncompetitive binding gave fluorescence signals that were comparable to controls where biotinylated antibodies were incubated with RBD beads in the absence of competitor. Biotinylated antibodies were prepared using the EZ-link NHS-PEG biotinylation kit (Pierce ThermoFisher) according to the manufacturer’s protocol.

[0417] Based on these studies, Red-E2 is a Class 1/ Class 2 antibody that shows strong competitive binding that may represent overlapping binding epitopes with REGN10933, AZD8895 and P5C3 mAbs (Fig. 24). Spike RBD pre-incubated with Red-E2 also exhibits partial competitive binding with the Class 3 mAbs REGN10987 and S309/Sotrovimab and is partially competitive with mAb clones P1G17 and P7K18. In contrast, Red-E2 binds non- competitively with all other Class 3 mAbs tested. [0418] The P4J15 mAb exhibits a competitive to partially competitive binding profile with almost all the biotinylated antibodies tested from the different binding classes. This profile is most similar to the Class 4 mAb, ADG-2 that may have this blocking activity by exerting a binding induced conformational change on RBD that prevents the binding of other mAbs, even if they do not bind overlapping epitopes.

[0419] The P5-I14 mAb shows competitive binding with all Class 1/2 mAbs but the binding epitope appears to be distinct in being strongly competitive with the Class 4 mAb ADG-2. PS- 114 also bind RBD non-competitively with all other Class 3 mAb tested and with multiple mAb clones (P1G17, M35, P2H13, P7K18) binding diverse epitopes on the RBD. Along with exhibiting strong competitive binding for ACE2, our studies support P5-I14 as binding an epitope that overlaps between the Class 1 and Class 4 binding sites on the inner side of the RBD.

[0420] The Red-Al mAb has a competitive binding profile that is consistent with a Class 3 mAb at an epitope that does not significantly inhibit the Spike-ACE2 interaction. Compared to the marketed S309/Sotrovimab antibody that is also non-blocking of the Spike-ACE2 interaction, Red-Al binds a distinct epitope since it is only partially competitive with biotinylated S309 mAb and is different in exerting a partially competitive binding profile with the Class 1 mAb REGN10933.

[0421] The competitive binding profile of P1N04 mAb is consistent with a Class 3 mAb that binds non-competitively with the Class 1, Class 2 and Class 4 mAbs tested. The binding profile and partial blocking of the Spike- ACE2 interaction mimics P2G3 closely, indicating that these mAbs are binding overlapping epitopes. The observation that both P2G3 and P1N04 lose binding affinity to the Spike Delta variant with the K444T substitutions further confirms the similarity of their binding epitopes.

Example 7: Cryo-electron microscopy structure of Red-E2 Fab in complex with the Spike trimer

[0422] To understand the structural basis of Red-E2 potent neutralization of SARS-CoV-2 variants of concern (VOC), the complex formed by Omicron BA.l SARS-CoV-2 Spike trimer and Red-E2 Fab fragments was characterized using single particle cryo-electron microscopy (Cryo-EM). In preparation of cryo-EM grids, Omicron Spike was mixed with Red-E2 Fab fragment at a 1 :3 molar ratio and applied to the glow-discharged grids. The best grids screened for particle presence were evaluated with cryo-EM data collected using TFS Titan Krios G4 transmission electron microscope, equipped with a Cold-FEG on a Falcon IV detector in electron counting mode. The EM map was generated by performing non-uniform refinement followed by local refinement of the Fab-RBD interacting region and finally an atomic model was built by positioning the Ca chains for the Fab and Spike. The single particle cryo-EM reconstruction of the Omicron Spike trimeric ectodomain bound to the Fabs at a 3.0 A resolution with Red-E2 Fabs binding RBD in the up- or open-conformation. Red-E2 binds RBD with a buried surface area of around 680 A² as a Class 1 neutralizing mAb, recognizing an epitope on the SARS-CoV-2 RBD that overlaps with receptor-binding motif (Fig. 5A). To characterize the Red-E2 paratope and epitope interface in detail, we performed local refinement of the Red-E2 Fab-RBD interacting region and reached a resolution of ~4 A with well-defined density, allowing clear interpretation of sidechain positions at the interface, where the resolution was closer to ~3.0 A resolution (Fig. 5A). The Red-E2 paratope is composed of five complementarity-determining region (CDR) loops binding at the RBD. The interactions are mediated through electrostatic and hydrophobic contacts (Fig. 5B) and involve fifteen residues of the RBD, bound by the three heavy chain and two light chain CDRs of the Red-E2 mAb. Central contacts between the RBD and Red-E2 are shown in Fig. 5B with RBD interactions including Asn417, Tyr421, Leu455, Phe456, Ala475 to Lys478, Asn481, Gly485 to Asn487, Tyr489, and Pro491 to Ser494. The binding epitope of Red-E2 is further defined in Fig. 5C with potential longer range interactions extending to a 6.5 A distance and compared to the ACE2 contact residues on the RBD and a comparison of epitopes for the Class 1 antibody P5C3 and Class 3 antibodies P2G3, Cilgavimab and Bebtelovimab. Although Red-E2 forms contacts with many of the same residues on the RBD compared to P5C3, binding and neutralization assay studies show that Red-E2 activity is optimized for many of the amino acid substitutions in the Omicron variant (shown with asterisk in Fig. 5C) that have evolved to endow the virus with improved ACE2 binding affinity, increased infectivity and resistance to a humoral immune response generated with SARS-CoV-2 vaccines. These substitutions present in the Omicron variants include Lys417Asn, Ser477Asn and Thr478Lys that could partially explain the 5- to 6-fold improved neutralizing potency of Red-E2 against omicron variants relative to the ancestral D614G and Delta variants with conserved residues Lys417 and Ser477. Red-E2 also forms distinct interactions with RBD compared to P5C3 including direct contacts with Tyr421 and Pro491. An unexpected consequence of Red-E2 exhibiting optimal binding to Spike sequences in the Omicron variant is that in order to evade neutralization by Red-E2, the virus will have to mutated some of these key residues needed for enhanced ACE2 binding, viral fitness and/or infectivity. A second unexpected advantage of the binding epitope targeted by Red-E2 is that the contact residues on the RBD are highly conserved in the GISAID sequence database (Table 13), indicating that they are crucial for maintaining Spike structure and/or key contacts with the ACE2 receptor that is essential to viral infection. All contact residues are >99.9% conserved relative to residues at this position that are effectively neutralized by the Red-E2 antibody.

Table 13: Sequence conservation of Spike RBD residues that form direct contacts with Red-E2.

[0423] In Table 13, Percent conservations is listed for substitutions at the indicated sites where Red-E2 has demonstrated activity for mutations in SARS-CoV-2 variants as indicated in Fig. 5C. Compiled sequences were analyzed for the three-month period from June 19^th to September 19^th 2022 comprising a total of 1’474’046 Spike sequences collected worldwide. [0424] Given that our structural studies show that Red-E2 binds distinct, non-competitive sites on the Spike protein RBD compared to P2G3 and Bebtelovimab antibodies, both these cocktails of antibodies with Red-E2 could represent ideal partners for combined administration as a combination therapy, exhibiting a more potent neutralizing activity against current viral variants and/or suppress the development of resistant variants of the SARS-CoV-2 virus. Together our structural and competitive binding studies show that Red-E2, P4J15 and P5-I14 bind with high affinity to Omicron Spike at distinct epitopes, and used as monotherapy or combined together or with Class 3 antibodies, could exhibit enhanced neutralizing activity and breadth in neutralizing current and emerging SARS-COV-2 variants of concern. In addition to the current unexpected advantage of maintaining potency against all past and current variants of concern, in binding distinct, highly conserved epitopes on the viral Spike protein, Red-E2, P4J15 and P5-I14 have the potential unexpected benefit of maintaining activity against a future variant of concern. As was observed with the emergence of the Omicron variant at the end of 2021 (https://doi.org/10.1038/s41586-021-Q4388-0 ) and the further evolution of the virus in the summer of 2022 (https://doi.org/10.1038/s41586-022-05Q53-w ) almost all therapeutic antibodies have lost activity against the most prevalent circulating SARS-CoV-2 virus. This creates an unprecedented unmet medical need for immunocompromised individuals, including patients with primary immunodeficiencies, those receiving immunosuppressive treatments for organ transplants and systemic inflammatory diseases or for some cancers that are now almost completely unprotected due to their inability to mount a protective humoral immune response following vaccination (https ://doi . org/ 10 , 1001 /i amaoncol ,2022 , 0446). The situation has become increasingly dire in the fall of 2022 (https://doi.Org/10.l 101/2022,09.15.507787) where it has been shown that Evusheld, the only approved treatment for prophylactic protection against SARS-CoV-2 infection, is now completely inactive against the Omicron BA.4.6 variant. Recent publications and analysis also show that there has been a significate increase of viral isolates that have mutations at position K444 of the Spike protein that confer near complete resistance to P2G3 and Bebtelovimab, the only neutralizing antibody currently available for therapeutic interventions for hospitalized COVID-19 patients. In the period of the last three months (June 19^th to Sept 19^th, 2022) the prevalence of mutations at K444 has increased almost 10-fold from 0.128% to 1.21%, presenting a very real risk that hospitalized COVID-19 patients and immunocompromised patients will have no options for antibody treatments. Given that Red-E2, P4J15 and P5-I14 maintain neutralizing activity against pseudoviruses produced with the Omicron B A.4 Spike encoding the K444T mutation, these antibodies are unique in potency and breadth. Taken together, the need for potent neutralizing antibodies binding diverse highly conserved sited on the SARS-CoV-2 Spike has never been greater.

Example 8: Cryo— electron microscopy structure of P4J15 Fab in complex with the Spike trimer

[0425] To understand the structural basis of P4J15’s potent neutralization of SARS-CoV-2 variants of concern (VOC), the complex formed by Omicron XBB.1 SARS-CoV-2 Spike trimer and P4J15 Fab fragments was characterized using single particle cryo-electron microscopy (Cryo-EM) as discussed in Example 7. The single particle cryo-EM reconstruction of the Omicron XBB Spike trimeric ectodomain bound to the Fab at a 3.01 A resolution and the P4J15 Fab binding RBD in the up- or open-conformation (Fig. 6A). P4J15 binds RBD with a buried surface area of around 814 A² as a Class 1 neutralizing mAb, recognizing an epitope on the SARS-CoV-2 RBD that overlaps with the ACE2 receptor-binding motif (Figs. 6B and 6C). To characterize the P4J15 paratope and epitope interface in detail, local refinement of the P4J15 Fab-RBD interacting region was performed and a resolution of 3.85 A with well-defined density was reached, allowing clear interpretation of sidechain positions at the interface. The P4J15 paratope interactions are mediated mainly through electrostatic and hydrophobic contacts and involve twenty-six residues of the RBD, bound by the three heavy chain CDRs, two light chain CDRs and residues of the heavy chain Frame region 3 of the P4J15 mAb. The P4J15 resides in the heavy chain that form a contact with RBD include Glu27, Ser28, Ser30, Asp31, Phe33 in CDR1, Trp47, Glu50, Thr52, His53, Thr54, Asn58 in CDR2, Thr73, Ser74 in Frame region 3 and ProlOO, LeulOl, Glyl02, Serl03, Ilel05, Argl07 in CDR3. P4J15 light chain contact residues include Ile29, Thr30, Asn31, Tyr32 in CDR1 and Phe91, Asp92, His93 and Leu94 in CDR3. Primary P4J14 residues that contact RBD are shown in Fig. 7A. Central contacts between the RBD and P4J15 are shown in Fig. 7B with interactions including Arg403, Tyr421, Tyr449, Tyr453, Leu455, Phe456, Arg457, Lys458, Tyr473, Ala475, Gly476, Asn477, Lys478, Gly485, Ser486, Asn487, Tyr489, Ser490, Leu492, Gln493, Ser494, Gly496, Arg498, Tyr501, Gly502 and His505. These contact residues are further depicted in Fig. 8 with a structural model of the RBD viewed from the top and the P4J 15 contact buried surface on RBD shaded in dark grey. P4 J 15 residues that make key interactions with the RBD are shown in stick representation. It is important to underscore that 22 of these P4J15 contact residues on RBD are shared with crucial contacts formed between RBD and the ACE2 receptor that is essential for virus binding and infection of target cells. These common contact residues on RBD for both P4J15 and ACE2 include Arg403, Tyr449, Tyr453, Leu455, Phe456, Tyr473, Ala475, Gly476, Asn477, Gly485, Ser486, Asn487, Tyr489, Ser490, Leu492, Gln493, Ser494, Gly496, Arg498, Tyr501, Gly502 and His505. The common area on RBD for these 22 residues that contact P4J15 and ACE2 is approximately 725 A² that corresponds to almost 90% of the P4J15 epitope and 82% of the 889 A² contact area with ACE2. Based on these observations, P4J15 may act as an ACE2 mimetic antibody and that it will be difficult for the virus to develop resistance mutations that completely disrupt P4J15 to RBD interactions without having an impact on the ACE2 to RBD interaction.

Example 9: Viral resistance studies to generate SARS-CoV-2 Spike escape mutations to P4J15.

[0426] To gain insight into the predicted clinical value of P4J15 and variant residues in the SARS-CoV-2 Spike that could impact the antibodies neutralizing activity, we characterized the emergence of mutants allowing viral escape in tissue culture studies. For this, we grew SARS- CoV-2 Omicron BA.2.75.2 and Omicron BQ. l variants in the presence of sub-optimal neutralizing doses of P4J15 for three passages to generate a heterogeneous viral population, before switching to stringent mAb concentrations in order to select bona fide escapes (Fig. 9A). Viral genome sequencing of these mAb -resistant mutants pointed to the importance of Spike substitutions F456S, A475D, G476D, N477D/K, N487S/D/K escaping P4J15 in the BA.2.75.2 selection studies and G476D, N487S/T/D/K, Y489H substitutions identified with BQ. l virus studies. The identified mutations were then generated in a Spike BA.2.75.2 and Spike BQ.l expression vector through site directed mutagenesis and used to generate the Spike virus-like particles (VLP). We thus tested the impact of these mutations on the neutralizing capacity of P4J15 and on viral infectivity of these Spike escape virus-like particles. P4 JI 5 -escaping Spike mutations in the BA.2.75.2 VLP assay that conferred a complete loss of neutralizing activity were F456S, A475V, G476D, N487D, N487K, and N487T while N477D, N477K and N487S exerted a 14 to 33-fold loss in activity (Fig. 10A). Similarly, in the BQ.l Spike VLP assay, G476D, N487D, N487K, and N487T escaped neutralization of P4J15 along with the Y489H mutation, while the N487S mutation was moderately more resistant to P4J15 (Fig. 10B). Despite the resistance conferred by these Spike mutations on the neutralizing potency of P4J15, the infectivity of the corresponding Spike VLPs were reduced in many of the escapes (Figs. 11A and 11B where * indicates resistance mutations) including A475D and N487D in the BA.2.75.2 Spike andN487D, N487K andN487T in BQ.l Spike. Furthermore, using the ACE2- RBD interactive tool developed by Jesse Bloom’s lab, it was determined that all the Spike escape mutations in RBD exhibited a strong, 1- to 3 -log reduced binding affinity for ACE2 relative to the Omicron BA.2 Spike reference strain used in their studies (Figs. 11C and 11D). The reduced binding affinity of ACE2 for the Spike RBD escape mutations was expected based on our structural data in Example 8 since these residues are important for both P4J 15 and ACE2 binding to RBD. Finally, the GISAID EpiCoV database was examined to determine the frequency of the Spike escape mutations to P4J15. These mutations were found to be exceedingly rare and present in < 0.0044% of the -15’000’000 deposited sequences to date. Overall, these studies show that escape mutations to P4J15 are only present in very low frequency in virus isolated from infected individuals, a fact that is consistent with these viruses having a reduced fitness due to low infectivity as shown in our in vitro experiments and/or reduced ACE2-RBD affinity (Figs. 11A-11D).

Example 10: Neutralization characteristics of P4J15 and mutational engineered P4J15 to de-risk residues with potential liabilities in pre-clinical development

[0427] Having identified P4J15 as a potent neutralizing antibody binding highly conserved residues on the RBD, we next evaluated the activity against a broad panel of SARS-CoV-2 Spike variants of concern. Potency was measured in lentivirus pseudo-typed and virus-like particle cell-based neutralization assays, both using Spike from the SARS-CoV-2 variants of concern indicated in Fig. 12. Evusheld and Bebtelovimab marketed anti-SARS-COV-2 antibody therapies were also evaluated for comparison purposes. These studies show P4J15 exhibits potent activity against all Spike variants evaluated including the SARS-CoV-2 D614G variant that emerged early on in the pandemic, Alpha, Beta, Delta, Omicron BA. l, BA.4/5, BA.2.75.2, BQ.1.1, XBB.l, XBB.1.5, CH.1.1, XBB.1.6, XBB.1.16.1, XBB.2.3, and EG.5.1 with EC50 values ranging between 14 to 41 ng/ml for pre-Omicron variants in the pseudoviral assay and EC50 values of 2 to 18 ng/ml in either pseudoviral and VLP assays for all post- Omicron variants. By comparison, the Evusheld combination of tixagevimab (AZD8895) and cilgavimab (AZDI 061) exhibits potent neutralizing activity of pre-Omicron variants, reduced activity against Omicron BA. l and BA.4/5 and no detectable neutralizing activity against the Omicron variants after BA.4/5. Bebtelovimab potently neutralizes all Spike variants up to Omicron BA.4/5 but then exhibited only nominal activity (>8760 ng/ml EC50) against all the most recent Spike variants tested. Overall, these results strongly support the use of P4J15 as a therapeutic and prophylactic agent against all current and past circulating SARS-CoV-2 viral variants.

[0428] Apart from the anti-SARS-CoV-2 neutralizing activity and in vivo efficacy studies discussed below (Examples 11 and 12), we evaluated the heavy and light chain sequences for optimization. In particular, we evaluated the sequences for the presence of motifs that could present development challenges, e.g., deamidation sensitive motifs, potential glycosylation motifs, acid cleavage or isomerization motifs, potential oxidation sites in CDR, Lys glycation motifs, and integrin binding motifs. The main amino acid sequence identified was an integrin binding motifs (Arg-Gly-Asp) present at residues 107-109 of the P4J15 heavy chain. Removal of a potential acid cleavage or isomerization motif at Asp99/Serl00 of the heavy chain was also evaluated. There were furthermore several somatic hypermutations in the frame region of the P4J 15 heavy chain that were back mutated to the germline sequence in a mutational engineering process that could lead to higher antibody production and/or stability. Neutralizing potency of the resulting P4J15 antibodies containing different combinations of these engineering mutations are shown in Fig. 13A along with the amino acid substitutions that the corresponding neutralizing activity against pseudoviruses produced with the XBB Spike or the Omicron B A.4 Spike that harbours the F486P substitution present in the XBB.1.5 variant (Fig. 13B). These studies show that the heavy chain P4J15 mutations of R107Q, G108P, G108V, G108F, D109E and D109Q lead to a significant loss in neutralizing activity for the corresponding P4J15 antibodies. Substitutions for G108A (present in P4J15-MX01, P4J15-MX08 and P4J15-MX10 mAbs) and G108S (present in the P4J14-MX13 mAb) all removed the integrin binding motif while maintaining comparable levels of neutralizing activity to the parent P4J15 antibody. The potential acid cleavage or isomerization motif at Asp99/Serl00 could be removed by introducing the S99A mutation which provided equivalent potency compared to antibodies with a Ser at this position (compare P4J15-MX08 with P4J15-MX10 in Fig. 13B). Germline reversions that were introduced without a loss in neutralizing potency for the resulting P4J15 mutant antibody include the substitutions I4L, W7S, S40P, M43K and M64K. The N76Y substitution was accepted in the P4J15 antibody with a potential small improvement in neutralizing potency while the M69I substitution consistently resulted in antibodies with a 4 to 5-fold loss in potency relative to the parent P4J15 antibody. Several of the prioritized optimization candidates were further evaluated against a panel of Spike variants and point mutations in the pseudoviral cell-based neutralization assay. These studies show that P4J15- MX08 has neutralizing EC50 values that are comparable to the parental antibody against all pseudoviruses tested (Fig. 14). Profiling of P4J15-MX08 continued with pseudoviral neutralization assays using SARS-CoV-2 Spike with the D614G, Beta and Delta variants, P4J15 escape mutations (BA.5 F486S, A475K, G476D N487D and N487S) and variant present at low frequency at the P4J15 binding epitope (BA.5 L455F, and N477G; Fig. 15). In all cases, the neutralizing potency observed for P4J15-MX08 were equivalent to EC50 values obtained for the parental P4J15, indicating that the de-risked antibody engineering exercise was successful in maintaining potency while removing potential liabilities that would only be observed later in development. Apart from neutralizing activity of the P4J15-MX08 antibody, produced with the Met428Leu/Asn434Ser or LS substitutions in the Fc domain (LS Xtend mutations by Xencor), the Fc mediated functional activity of the antibody was evaluated in an in vitro antibody dependent cellular phagocytosis (ADCP) assay. These tests are performed by mixing different concentrations of antibody with Spike Omicron BA.1 coated fluorescent beads followed by an overnight incubation with the U937 monocyte cell line. This monocyte cell line expresses high levels of Fc-gamma receptors capable of inducing phagocytosis of opsonized viruses or beads coated with the Spike antigen as in our assay. Phagocytosis of the fluorescent beads was monitored by flow cytometry by gating of cells with and without intracellular beads. Of note, the ADCP activity of an antibody is independent of its neutralizing activity and depends on both efficient binding to the Spike protein and the epitope being targeted. As shown in Fig. 16A, P4J15-MX08 exhibited potent ADCP activity against Omicron BA.l Spike that was at similar levels with the Sotrovimab and Bebtelovimab class 3 binding epitope antibodies that are known to have potent Fc mediated functional activity. P4J15-MX08 exhibited moderately superior ADCP activity compared to the class 3 antibody cilgavimab (AZDI 061) and significantly better ADCP activity compared to the class 1 antibody tixagevimab (AZD8895). As shown in Fig. 16B, P4J15-MX08 and Sotrovimab exhibited potent ADCP activity against Omicron XBB.l Spike while the remaining antibodies tested were inactive. These studies confirm that in addition to possessing potent neutralizing activity, P4J15-MX08 will also benefit from enhanced antiviral activity in vivo due to this demonstrated Fc mediate functional activity.

Table 14: VH amino acid sequences for P4J15 variants

Table 15: HCDR3 amino acid sequences for P4J15 variants

Example 11: Prophylactic use of P4J15 LS in the hamster Omicron BA.5 infection model [0429] To further validate the potency of P4J15, in vivo live virus challenge experiments were performed in a prophylactic hamster challenge model of SARS-CoV-2 infection. Animals were dosed with 5, 1 or 0.5 mg/kg of P4J14, 5 mg/kg of bebtelovimab or a human IgGl control, challenged two days later with an intranasal inoculation of the Omicron BA.5 SARS-CoV-2 virus (Fig. 17A) and then four days later, hamster lung tissue was monitored for infectious virus and viral RNA. Infectious virus was undetectable in lungs from almost all P4J15 treated hamsters, with only 1 of 6 hamsters in the lowest dosed 0.5 mg/kg group showing a >2-log reduction in levels of infectious virus compared to the isotype mAb-treated control animals (Fig. 17B). By comparison, 1 of 6 hamsters in the 5 mg/kg bebtelovimab dosed animals had detectable levels of infectious virus. Importantly, protective plasma levels of P4J15 in Omicron BA.5 challenged hamsters was shown to be ~7 pg/ml, while in the bebtelovimab arm of the study, the one treated animal with detectable infection virus in the lung had mAb plasma levels of 83 pg/ml. Interestingly, although all P4J15 treatment groups showed a significant reduction of genomic viral RNA levels, relatively high levels were detected in two and three hamsters for the 1 and 0.5 mg/kg dosing arms (Fig. 17C). This indicates that although P4J15 treatments practically eliminated infectious virus, RNA, potentially from inactivated virus was still detectable four days post challenge. Example 12: P4J15 exhibits complete prophylactic therapeutic efficacy in cynomolgus macaques

[0430] P4J15 LS with M428L/N434S half-life extension mutations in the Fc domain was evaluated in mediating protection from SARS-CoV-2 Omicron XBB.1.5 infection in a cynomolgus macaques pre-exposure challenge study. Monkeys (n=6) were administered 5 mg/kg of P4J15 intravenously and challenged 72 hrs later via combined intranasal and intratracheal routes with IxlO⁵ TCID50 of SARS-CoV-2 Omicron XBB.1.5 virus. Following viral challenge, control animals (n=6) showed similar genomic (g)RNA levels and kinetics with median peak viral loads (VL) of 7.5- ,7.0 and 6.0-logl0 copies/ml gRNA at 2-3 days post challenge in nasopharyngeal swabs, tracheal swabs and bronchoalveolar lavage (BAL) samples, respectively (panels A-C of Fig. 18). In comparison, the six P4J15 LS treated monkeys had essentially undetectable levels of gRNA in all sample and timepoints tested. This full protection by P4J15 LS was further confirmed by evaluating signs of active viral replication, as assessed by subgenomic (sg)RNA levels, peaked 3-4 days post-challenge with nasopharyngeal swabs, tracheal swabs and BAL showing median values of 5.1- 5.0 and 4.2-loglO copies per ml (panels D-F of Fig. 18). P4J15 LS treated monkeys had undetectable levels of sgRNA levels throughout the testing period in any of the samples evaluated. This indicates an absence of any replicating virus and complete prophylactic protection provided by the P4J15 LS antibody, a result to our knowledge that is unparalleled with all other anti-SARS-COV-2 antibodies tested to date in this monkey model.

Table 16. Amino acid substitutions and deletions on SARS-CoV-2 variants of concern

* Indicates that variant has different sub-populations that may or may not include the indicatec amino acid substitutions.

[0431] Sequence of the ancestral Wuhan (2019-nCoV) SARS-CoV-2 Spike protein (SEQ ID NO: 41). RBD residues 333 to 527 in bold.

MFVFLVLLPL VSSQCVNLTT RTQLPPAYTN SFTRGVYYPD KVFRSSVLHS

TQDLFLPFFS NVTWFHAIHV SGTNGTKRFD NPVLPFNDGV YFASTEKSNI

IRGWIFGTTL DSKTQSLLIV NNATNVVIKV CEFQFCNDPF LGVYYHKNNK SWMESEFRVY SSANNCTFEY VSQPFLMDLE GKQGNFKNLR EFVFKNIDGY

FKIYSKHTPI NLVRDLPQGF SALEPL VDLP IGINITRFQT LLALHRSYLT

PGDSSSGWTA GAAAYYVGYL QPRTFLLKYN ENGTITDAVD CALDPLSETK CTLKSFTVEK GIYQTSNFRV QPTESIVRFP NITNLCPFGE VFNATRFASV

YAWNRKRISN CVADYSVLYN SASFSTFKCY GVSPTKLNDL CFTNVYADSF VIRGDEVRQI APGQTGKIAD YNYKLPDDFT GCVIAWNSNN LDSKVGGNYN YLYRLFRKSN LKPFERDIST EIYQAGSTPC NGVEGFNCYF PLQSYGFQPT NGVGYQPYRV VVLSFELLHA PATVCGPKKS TNLVKNKCVN FNFNGLTGTG VLTESNKKFL PFQQFGRDIA DTTDAVRDPQ TLEILDITPC SFGGVSVITP GTNTSNQVAV LYQGVNCTEV PVAIHADQLT PTWRVYSTGS NVFQTRAGCL IGAEHVNNSY ECDIPIGAGI CASYQTQTNS PRRARSVASQ SIIAYTMSLG AENSVAYSNN SIAIPTNFTI SVTTEILPVS MTKTSVDCTM YICGDSTECS

NLLLQYGSFC TQLNRALTGI AVEQDKNTQE VFAQVKQIYK TPPIKDFGGF NFSQILPDPS KPSKRSFIED LLFNKVTLAD AGFIKQYGDC LGDIAARDLI

CAQKFNGLTV LPPLLTDEMI AQYTSALLAG TITSGWTFGA GAALQIPFAM QMAYRFNGIG VTQNVLYENQ KLIANQFNSA IGKIQDSLSS TASALGKLQD

VVNQNAQALN TLVKQLSSNF GAISSVLNDI LSRLDKVEAE VQIDRLITGR

LQSLQTYVTQ QLIRAAEIRA SANLAATKMS ECVLGQSKRV DFCGKGYHLM SFPQSAPHGV VFLHVTYVPA QEKNFTTAPA ICHDGKAHFP REGVFVSNGT HWFVTQRNFY EPQIITTDNT FVSGNCDVVI GIVNNTVYDP LQPELDSFKE

ELDKYFKNHT SPDVDLGDIS GINASVVNIQ KEIDRLNEVA KNLNESLIDL

QELGKYEQYI KWPWYIWLGF IAGLIAIVMV TIMLCCMTSC CSCLKGCCSC

GSCCKFDEDD SEPVLKGVKL HYT

[0432] It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the present description.

[0433] Various publications, articles and patents are cited or described in the background and throughout the specification; each of these references is herein incorporated by reference in its entirety. Discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is for the purpose of providing context for the invention.

Such discussion is not an admission that any or all of these matters form part of the prior art with respect to any inventions disclosed or claimed.

Claims

1. An antibody or antigen-binding fragment thereof that binds to the Spike protein of a Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), wherein the antibody or antigen-binding fragment thereof comprises: a. a variable heavy chain CDR1 (HCDR1) comprising an amino acid sequence selected from SEQ ID No: 9, 12, 15, 18, and 44; b. a variable heavy chain CDR2 (HCDR2) comprising an amino acid sequence of SEQ ID No: 10, 13, 16, 19, and 45; c. a variable heavy chain CDR3 (HCDR3) comprising an amino acid sequence selected from SEQ ID No: 11, 14, 17, 20, 46, 66, 67, 68, and 69; d. a variable light chain CDR1 (LCDR1) comprising an amino acid sequence selected from SEQ ID No: 21, 24, 27, 30, and 47; e. a variable light chain CDR2 (LCDR2) comprising an amino acid sequence selected from SEQ ID No: 22, 25, 28, 31, and 48; and f. a variable light chain CDR3 (LCDR3) comprising an amino acid sequence selected from SEQ ID No: 23, 26, 29, 32, and 49.

2. The antibody or antigen-binding fragment thereof of claim 1, wherein the antibody or antigen-binding fragment thereof comprises: a HCDR1 comprising an amino acid sequence of SEQ ID No: 9, a HCDR2 comprising an amino acid sequence of SEQ ID No: 10, a HCDR3 comprising an amino acid sequence of SEQ ID No: 11, a LCDR1 comprising an amino acid sequence of SEQ ID No: 21, a LCDR2 comprising an amino acid sequence of SEQ ID No: 22, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 23.

3. The antibody or antigen-binding fragment thereof of claim 2, wherein the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 1, and a light chain variable domain (VL) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 5.

4. The antibody or antigen-binding fragment thereof of claim 2 or claim 3, wherein the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 1, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 5.

5. The antibody or antigen-binding fragment thereof of claim 1, wherein the antibody or antigen-binding fragment thereof comprises a HCDR1 comprising an amino acid sequence of SEQ ID No: 12, a HCDR2 comprising an amino acid sequence of SEQ ID No: 13, a HCDR3 comprising an amino acid sequence of SEQ ID No: 14, a LCDR1 comprising an amino acid sequence of SEQ ID No: 24, a LCDR2 comprising an amino acid sequence of SEQ ID No: 25, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 26.

6. The antibody or antigen-binding fragment thereof of claim 5, wherein the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 2, and a light chain variable domain (VL) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 6.

7. The antibody or antigen-binding fragment thereof of claim 5 or claim 6, wherein the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 2, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 6.

8. The antibody or antigen-binding fragment thereof of claim 1, wherein the antibody or antigen-binding fragment thereof comprises a HCDR1 comprising an amino acid sequence of SEQ ID No: 15, a HCDR2 comprising an amino acid sequence of SEQ ID No: 16, a HCDR3 comprising an amino acid sequence SEQ ID No: 17, a LCDR1 comprising an amino acid sequence of SEQ ID No: 27, a LCDR2 comprising an amino acid sequence of SEQ ID No: 28, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 29.

9. The antibody or antigen-binding fragment thereof of claim 8, wherein the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 3, and a light chain variable domain (VL) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 7.

10. The antibody or antigen-binding fragment thereof of claim 8 or claim 9, wherein the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 3, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 7.

11. The antibody or antigen-binding fragment thereof of claim 8, wherein the HCDR3 comprises an amino acid substitution selected from S99A, G108A, and/or G108S relative to SEQ ID NO: 17.

12. The antibody or antigen-binding fragment thereof of claim 11, wherein the VH sequence is selected from SEQ ID Nos: 60-65.

13. The antibody or antigen-binding fragment thereof of claim 1, wherein the antibody or antigen-binding fragment thereof comprises a HCDR1 comprising an amino acid sequence of SEQ ID No: 18, a HCDR2 comprising an amino acid sequence of SEQ ID No: 19, a HCDR3 comprising an amino acid sequence of SEQ ID No: 20, a LCDR1 comprising an amino acid sequence of SEQ ID No: 30, a LCDR2 comprising an amino acid sequence of SEQ ID No: 31, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 32.

14. The antibody or antigen-binding fragment thereof of claim 13, wherein the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 4, and a light chain variable domain (VL) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 8.

15. The antibody or antigen-binding fragment thereof of claim 13 or claim 14, wherein the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 4, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 8.

16. The antibody or antigen-binding fragment thereof of claim 1, wherein the antibody or antigen-binding fragment thereof comprises a HCDR1 comprising an amino acid sequence of SEQ ID No: 44, a HCDR2 comprising an amino acid sequence of SEQ ID No: 45, a HCDR3 comprising an amino acid sequence of SEQ ID No: 46, a LCDR1 comprising an amino acid sequence of SEQ ID No: 47, a LCDR2 comprising an amino acid sequence of SEQ ID No: 48, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 49.

17. The antibody or antigen-binding fragment thereof of claim 16, wherein the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 42, and a light chain variable domain (VL) comprising an amino acid sequence that is at least about 75%, at least 85%, at least 90%, at least 95%, at least 99%, or 100% identical to SEQ ID No: 43.

18. The antibody or antigen-binding fragment thereof of claim 16 or claim 17, wherein the antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 42, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 43.

19. The antibody or antigen-binding fragment thereof of any one of claims 1-18, wherein the antibody or antigen-binding fragment thereof is a fully human antibody or antigen-binding fragment thereof.

20. The antibody or antigen-binding fragment thereof of any one of claims 1-19, wherein the antibody or antigen-binding fragment thereof binds to an epitope within the receptor binding domain (RBD) or the N-terminal domain (NTD).

21. The antibody or antigen-binding fragment thereof of any one of claims 1-20, wherein the antibody or antigen-binding fragment thereof neutralizes SARS-CoV-2.

22. The antibody or antigen-binding fragment thereof of claim 21, wherein the antibody or antigen-binding fragment thereof inhibits the fusion of SARS-CoV-2 and host cell membrane.

23. The antibody or antigen-binding fragment thereof of any one of claims 1-22, wherein the antibody or antigen-binding fragment thereof is cytotoxic to a SARS-CoV-2 infected host cell.

24. The antibody or antigen-binding fragment thereof of any one of the preceding claims, wherein the antibody or antigen-binding fragment thereof is a multivalent antibody comprising (a) a first target binding site that specifically binds to an epitope within the spike polypeptide, and (b) a second target binding site that binds to an epitope on a different epitope on the spike polypeptide or a different molecule.

25. The antibody or the antigen-binding fragment thereof of any one of the preceding claims, further comprising a variant Fc constant region.

26. The antibody or antigen-binding fragment thereof of any one of the preceding claims, wherein the antibody is a antibody, a chimeric antibody, a humanized antibody, or humanized antibody.

27. The antibody or antigen-binding fragment thereof of any one of the preceding claims, wherein the antigen-binding fragment is a single-chain antibody, Fab, or Fab2 fragment.

28. The antibody or antigen-binding fragment thereof of any one of the preceding claims, wherein the antibody or antigen-binding fragment thereof is detectably labeled or conjugated to a toxin, a therapeutic agent, a polymer, a receptor, an enzyme, or a receptor ligand, preferably wherein the polymer is polyethylene glycol (PEG).

29. A polynucleotide encoding the antibody or antigen-binding fragment thereof of any one of claims 1-28.

30. A vector, comprising the polynucleotide of claim 29.

31. A cultured host cell comprising the vector of claim 30

32. A pharmaceutical composition comprising the antibody or antigen-binding fragment thereof of any one of claims 1-28, the polynucleotide of claim 29, or the vector of claim 30.

33. A pharmaceutical composition comprising two or more of antibodies or antigen binding fragments thereof, wherein the two or more antibodies or antigen binding fragments thereof are selected from: a. an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 9, a HCDR2 comprising an amino acid sequence of SEQ ID No: 10, a HCDR3 comprising an amino acid sequence of SEQ ID No: 11, a LCDR1 comprising an amino acid sequence of SEQ ID No: 21, a LCDR2 comprising an amino acid sequence of SEQ ID No: 22, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 23; b. an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 12, a HCDR2 comprising an amino acid sequence of SEQ ID No: 13, a HCDR3 comprising an amino acid sequence of SEQ ID No: 14, a LCDR1 comprising an amino acid sequence of SEQ ID No: 24, a LCDR2 comprising an amino acid sequence of SEQ ID No: 25, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 26; c. an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 15, a HCDR2 comprising an amino acid sequence of SEQ ID No: 16, a HCDR3 comprising an amino acid sequence of SEQ ID No: 17, a LCDR1 comprising an amino acid sequence of SEQ ID No: 27, a LCDR2 comprising an amino acid sequence of SEQ ID No: 28, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 29; d. an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 18, a HCDR2 comprising an amino acid sequence of SEQ ID No: 19, a HCDR3 comprising an amino acid sequence of SEQ ID No: 20, a LCDR1 comprising an amino acid sequence of SEQ ID No: 30, a LCDR2 comprising an amino acid sequence of SEQ ID No: 31, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 32; e. an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 44, a HCDR2 comprising an amino acid sequence of SEQ ID No: 45, a HCDR3 comprising an amino acid sequence of SEQ ID No: 46, a LCDR1 comprising an amino acid sequence of SEQ ID No: 47, a LCDR2 comprising an amino acid sequence of SEQ ID No: 48, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 49; f. Bebtelovimab; g. the P2G3 antibody; and h. a combination thereof.

34. The pharmaceutical compositions of claim 33, wherein the two or more antibodies or antigen binding fragments thereof are selected from a. an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 1, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 5; b. an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 2, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 6; c. an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 3, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 7; d. an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 4, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 8; e. an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 42, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 43; f. Bebtelovimab; g. the P2G3 antibody; and h. a combination thereof.

35. The pharmaceutical composition of any one of claims 32-34, wherein the pharmaceutical composition further comprises a pharmaceutical acceptable carrier.

36. The pharmaceutical composition of any one of claims 32-35, for use in treating a SARS- CoV-2 infection in a subject.

37. A method of treating a SARS-CoV-2 infection in a subject, comprising administering to the subject therapeutically effective amount of the antibody or antigen-binding fragment thereof of any one of claims 1-28 or a therapeutically effective amount of the pharmaceutical composition of any one of claims 32-35.

38. A method of neutralizing SARS-CoV-2 in a subject, comprising administering to a subject in need thereof a therapeutically effective amount of the antibody or antigen-binding fragment thereof of any one of claims 1-28 or a therapeutically effective amount of the pharmaceutical composition of any one of claims 32-35.

39. A method of preventing a SARS-CoV-2 infection in a subject, comprising administering to a subj ect in need thereof a therapeutically effective amount of the antibody or antigen-binding fragment thereof of any one of claims 1-28 or a therapeutically effective amount of the pharmaceutical composition of any one of claims 32-35.

40. The method of any one of claims 37-39, wherein the subject is immunocompromised.

41. The method of any one of claims 37-40, wherein the method further comprises administering a second therapeutic agent, preferably wherein the second therapeutic agent comprises an anti-inflammatory drug or an antiviral compound.

42. The method of claim 41, wherein: (a) the antiviral compound comprises: a nucleoside analog, a peptoid, an oligopeptide, a polypeptide, a protease inhibitor, a 3C-like protease inhibitor, a papain-like protease inhibitor, or an inhibitor of an RNA dependent RNA polymerase; or (b) the antiviral compound is selected from: acyclovir, gancyclovir, vidarabine, foscamet, cidofovir, amantadine, ribavirin, trifluorothymidine, zidovudine, didanosine, zalcitabine, and an interferon, and preferably wherein the interferon is an interferon-a or an interferon-p.

43. The method of claim 41 or claim 42, wherein the second therapeutic agent is administered before, after, or concurrently with the antibody or pharmaceutical composition thereof.

44. The method of any one of claim 37 or 38, wherein the pharmaceutical composition is administered to the subject after the exposure to SARS-CoV-2.

45. A kit for detecting a SARS-CoV-2 infection in a subject, comprising the antibody or antigen-binding fragment thereof of any one of claims 1-28.

46. A method of detecting the presence of a SARS-CoV-2 in a sample, comprising (1) contacting the sample with the antibody or antigen-binding fragment thereof of any one of claims 1-28, and (2) detecting the presence of an antibody-antigen complex, wherein the presence of the antibody-antigen complex indicates the presence of SARS-CoV-2.

47. The method of claim 46, wherein the antibody or antigen-binding fragment thereof is conjugated to a label, preferably wherein the label is selected from a fluorescent label, a chemiluminescent label, a radiolabel, and an enzyme.

48. The method of claim 46 or claim 47, further comprising contacting a secondary antibody with the antibody or antigen-binding fragment thereof, wherein the secondary antibody comprises a label.

49. The method of claim 48, further comprising detecting fluorescence or chemiluminescence of the label, preferably wherein the step of detecting comprises a competitive binding assay or ELISA.

50. The method of any one of claims 46-49, further comprising binding the sample to a solid support, preferably wherein the solid support is selected from microparticles, microbeads, magnetic beads, and an affinity purification column.

51. The method of any one of claims 46-50, wherein the sample is a blood sample, a nasal swab, or a throat swab.

52. A method of preparing a antibody, or antigen-binding fragment thereof, comprising: a. obtaining the cultured host cell of claim 31 ; b. culturing the cultured host cell in a medium under conditions permitting expression of a polypeptide encoded by the vector and assembling of an antibody or fragment thereof; and c. purifying the antibody or fragment from the cultured cell or the medium of the cell.

53. A kit comprising a pharmaceutically acceptable dose unit of the antibody or antigenbinding fragment thereof of any one of claims 1-28 or the pharmaceutical composition of any one of claims 32-35.

54. A kit for the diagnosis, prognosis or monitoring treatment of SARS-CoV-2 in a subject, comprising: the antibody or antigen-binding fragment thereof of any one of claims 1-28; and at least one detection reagent that binds specifically to the antibody or antigen-binding fragment thereof.

55. A method of neutralizing SARS-CoV-2 in a subject, comprising administering to a subject in need thereof a therapeutically effective amount of two or more monoclonal antibodies or antigen-binding fragments thereof of any one of claims 1-28.

56. A method of treating a SARS-CoV-2 in a subject in need thereof, comprising administering to a subject in need thereof a therapeutically effective amount of two or more monoclonal antibodies or antigen-binding fragments thereof of any one of claims 1-28.

57. A method of preventing a SARS-CoV-2 in a subject in need thereof, comprising administering to a subject in need thereof a therapeutically effective amount of two or more monoclonal antibodies or antigen-binding fragments thereof of any one of claims 1-28.

58. The method of any one of claims 55-57, wherein the two or more antibodies or antigenbinding fragments thereof are selected from: a. an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 9, a HCDR2 comprising an amino acid sequence of SEQ ID No: 10, a HCDR3 comprising an amino acid sequence of SEQ ID No: 11, a LCDR1 comprising an amino acid sequence of SEQ ID No: 21, a LCDR2 comprising an amino acid sequence of SEQ ID No: 22, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 23; b. an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 12, a HCDR2 comprising an amino acid sequence of SEQ ID No: 13, a HCDR3 comprising an amino acid sequence of SEQ ID No: 14, a LCDR1 comprising an amino acid sequence of SEQ ID No: 24, a LCDR2 comprising an amino acid sequence of SEQ ID No: 25, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 26; c. an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 15, a HCDR2 comprising an amino acid sequence of SEQ ID No: 16, a HCDR3 comprising an amino acid sequence of SEQ ID No: 17, a LCDR1 comprising an amino acid sequence of SEQ ID No: 27, a LCDR2 comprising an amino acid sequence of SEQ ID No: 28, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 29; d. an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 18, a HCDR2 comprising an amino acid sequence of SEQ ID No: 19, a HCDR3 comprising an amino acid sequence of SEQ ID No: 20, a LCDR1 comprising an amino acid sequence of SEQ ID No: 30, a LCDR2 comprising an amino acid sequence of SEQ ID No: 31, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 32; e. an antibody or antigen-binding fragment thereof comprising: a HCDR1 comprising an amino acid sequence of SEQ ID No: 44, a HCDR2 comprising an amino acid sequence of SEQ ID No: 45, a HCDR3 comprising an amino acid sequence of SEQ ID No: 46, a LCDR1 comprising an amino acid sequence of SEQ ID No: 47, a LCDR2 comprising an amino acid sequence of SEQ ID No: 48, and a LCDR3 comprising an amino acid sequence of SEQ ID No: 49; f. Bebtelovimab; g. the P2G3 antibody; and h. a combination thereof.

59. The method of claim 58, wherein the two or more monoclonal antibodies or antigen binding fragments thereof are selected from: a. an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 1, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 5; b. an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 2, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 6; c. an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 3, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 7; d. an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 4, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 8; e. an antibody or antigen-binding fragment thereof comprises a heavy chain variable domain (VH) comprising or consisting of the amino acid sequence of SEQ ID No: 42, and a light chain variable domain (VL) comprising or consisting of the amino acid sequence of SEQ ID No: 43; f. Bebtelovimab; g. the P2G3 antibody; and h. a combination thereof.

60. The method of any one of claims 55-59, wherein the first antibody or antigen-binding fragment thereof and the second antibody or antigen binding fragment thereof exhibit synergistic activity.

61. The method of any one of claims 55-60, further comprising administering to the subject a therapeutically effective amount of a second therapeutic agent or therapy.

62. The method of claim 61, wherein the second therapeutic agent comprises an antiinflammatory drug or an antiviral compound.

63. The method of claim 62, wherein: (a) the antiviral compound comprises: a nucleoside analog, a peptoid, an oligopeptide, a polypeptide, a protease inhibitor, a 3C-like protease inhibitor, a papain-like protease inhibitor, or an inhibitor of an RNA dependent RNA polymerase; or (b) the antiviral compound is selected from: acyclovir, gancyclovir, vidarabine, foscamet, cidofovir, amantadine, ribavirin, trifluorothymidine, zidovudine, didanosine, zalcitabine, and an interferon, and preferably wherein the interferon is an interferon-a or an interferon-p.

64. The method of any one of claims 55-63, wherein the first antibody or antigen-binding fragment thereof is administered before, after, or concurrently with the second antibody or antigen-binding fragment thereof.

65. The method of any one of claims 37-44 or 55-64, wherein the antibody or antigenbinding fragment thereof is administered to the subject intravenously, subcutaneously, or intraperitoneally.