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NZ736728B2 - Cd123 antibodies and conjugates thereof - Google Patents

Cd123 antibodies and conjugates thereof Download PDF

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Publication number
NZ736728B2
NZ736728B2 NZ736728A NZ73672816A NZ736728B2 NZ 736728 B2 NZ736728 B2 NZ 736728B2 NZ 736728 A NZ736728 A NZ 736728A NZ 73672816 A NZ73672816 A NZ 73672816A NZ 736728 B2 NZ736728 B2 NZ 736728B2
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NZ
New Zealand
Prior art keywords
antibody
seq
chain variable
occupied
variable region
Prior art date
Application number
NZ736728A
Other versions
NZ736728A (en
Inventor
Django Sussman
May Kung Sutherland
Lori Westendorf
Original Assignee
Seagen Inc
Filing date
Publication date
Application filed by Seagen Inc filed Critical Seagen Inc
Priority claimed from PCT/US2016/036631 external-priority patent/WO2016201065A1/en
Publication of NZ736728A publication Critical patent/NZ736728A/en
Publication of NZ736728B2 publication Critical patent/NZ736728B2/en

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    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K39/00Medicinal preparations containing antigens or antibodies
    • A61K2039/505Medicinal preparations containing antigens or antibodies comprising antibodies
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00Medicinal preparations containing organic active ingredients
    • A61K31/33Heterocyclic compounds
    • A61K31/395Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
    • A61K31/55Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having seven-membered rings, e.g. azelastine, pentylenetetrazole
    • A61K31/551Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having seven-membered rings, e.g. azelastine, pentylenetetrazole having two nitrogen atoms, e.g. dilazep
    • A61K31/55131,4-Benzodiazepines, e.g. diazepam or clozapine
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00Medicinal preparations containing organic active ingredients
    • A61K31/33Heterocyclic compounds
    • A61K31/395Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins
    • A61K31/55Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having seven-membered rings, e.g. azelastine, pentylenetetrazole
    • A61K31/551Heterocyclic compounds having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins having seven-membered rings, e.g. azelastine, pentylenetetrazole having two nitrogen atoms, e.g. dilazep
    • A61K31/55131,4-Benzodiazepines, e.g. diazepam or clozapine
    • A61K31/55171,4-Benzodiazepines, e.g. diazepam or clozapine condensed with five-membered rings having nitrogen as a ring hetero atom, e.g. imidazobenzodiazepines, triazolam
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K39/00Medicinal preparations containing antigens or antibodies
    • A61K39/395Antibodies; Immunoglobulins; Immune serum, e.g. antilymphocytic serum
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/68Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment
    • A61K47/6801Drug-antibody or immunoglobulin conjugates defined by the pharmacologically or therapeutically active agent
    • A61K47/6803Drugs conjugated to an antibody or immunoglobulin, e.g. cisplatin-antibody conjugates
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/68Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment
    • A61K47/6801Drug-antibody or immunoglobulin conjugates defined by the pharmacologically or therapeutically active agent
    • A61K47/6803Drugs conjugated to an antibody or immunoglobulin, e.g. cisplatin-antibody conjugates
    • A61K47/68035Drugs conjugated to an antibody or immunoglobulin, e.g. cisplatin-antibody conjugates the drug being a pyrrolobenzodiazepine
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/68Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment
    • A61K47/6835Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment the modifying agent being an antibody or an immunoglobulin bearing at least one antigen-binding site
    • A61K47/6849Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment the modifying agent being an antibody or an immunoglobulin bearing at least one antigen-binding site the antibody targeting a receptor, a cell surface antigen or a cell surface determinant
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/50Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates
    • A61K47/51Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent
    • A61K47/68Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment
    • A61K47/6835Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment the modifying agent being an antibody or an immunoglobulin bearing at least one antigen-binding site
    • A61K47/6851Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient the non-active ingredient being chemically bound to the active ingredient, e.g. polymer-drug conjugates the non-active ingredient being a modifying agent the modifying agent being an antibody, an immunoglobulin or a fragment thereof, e.g. an Fc-fragment the modifying agent being an antibody or an immunoglobulin bearing at least one antigen-binding site the antibody targeting a determinant of a tumour cell
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00Medicinal preparations characterised by special physical form
    • A61K9/08Solutions
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61PSPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P35/00Antineoplastic agents
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61PSPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P35/00Antineoplastic agents
    • A61P35/02Antineoplastic agents specific for leukemia
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K16/00Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/18Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
    • C07K16/28Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants
    • C07K16/2866Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants against receptors for cytokines, lymphokines, interferons
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K16/00Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/18Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
    • C07K16/28Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants
    • C07K16/30Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants from tumour cells
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2317/00Immunoglobulins specific features
    • C07K2317/10Immunoglobulins specific features characterized by their source of isolation or production
    • C07K2317/14Specific host cells or culture conditions, e.g. components, pH or temperature
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2317/00Immunoglobulins specific features
    • C07K2317/20Immunoglobulins specific features characterized by taxonomic origin
    • C07K2317/21Immunoglobulins specific features characterized by taxonomic origin from primates, e.g. man
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2317/00Immunoglobulins specific features
    • C07K2317/20Immunoglobulins specific features characterized by taxonomic origin
    • C07K2317/24Immunoglobulins specific features characterized by taxonomic origin containing regions, domains or residues from different species, e.g. chimeric, humanized or veneered
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2317/00Immunoglobulins specific features
    • C07K2317/50Immunoglobulins specific features characterized by immunoglobulin fragments
    • C07K2317/52Constant or Fc region; Isotype
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2317/00Immunoglobulins specific features
    • C07K2317/50Immunoglobulins specific features characterized by immunoglobulin fragments
    • C07K2317/56Immunoglobulins specific features characterized by immunoglobulin fragments variable (Fv) region, i.e. VH and/or VL
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2317/00Immunoglobulins specific features
    • C07K2317/70Immunoglobulins specific features characterized by effect upon binding to a cell or to an antigen
    • C07K2317/73Inducing cell death, e.g. apoptosis, necrosis or inhibition of cell proliferation
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2317/00Immunoglobulins specific features
    • C07K2317/90Immunoglobulins specific features characterized by (pharmaco)kinetic aspects or by stability of the immunoglobulin
    • C07K2317/92Affinity (KD), association rate (Ka), dissociation rate (Kd) or EC50 value

Abstract

The invention provides murine, chimeric, and humanized antibodies that specifically bind to CD123 and conjugates thereof.

Claims (1)

1.SUMMARY OF THE CLAIMED INVENTION Provided herein are anti-CD123 antibodies and CD123 directed antibody-drug conjugates. In particular, provided herein are CD123 directed pyrrolobenzodiazepine (“PBD”) antibody-drug conjugates and the use of such conjugates to treat CD123 expressing disorders. Thus, in a first aspect, the invention provides an anti-CD123 antibody-drug conjugate compound having the formula: or a pharmaceutically acceptable salt, solvate, or solvate of the salt; wherein the subscript n is 1 or 3; the subscript m is 2 to 5 Ab is an anti-CD123 intact antibody or antigen binding fragment thereof comprising a heavy chain variable region having the amino acid sequence set forth in SEQ ID NO:1; and a light chain variable region having the amino acid sequence set forth in SEQ ID NO:2; the subscript p is an integer from 1 to 4. In a second aspect, the invention provides a pharmaceutical composition comprising a population of anti-CD123 antibody-drug conjugate molecules having the formula: or a pharmaceutically acceptable salt, solvate, or solvate of the salt; wherein the subscript n is 1 to 3; the subscript m is 2 to 5 Ab is an anti-CD123 intact antibody or antigen binding fragment thereof comprising a heavy chain variable region having the amino acid sequence set forth in SEQ ID NO:1; and a light chain variable region having the amino acid sequence set forth in SEQ ID NO:2; the subscript p is an integer from 1 to 4; and the average drug load of the composition is about 2. In a third aspect, the invention provides an antibody-drug conjugate composition comprising a population of anti-CD123 antibody-drug conjugate molecules having the formula: or a pharmaceutically acceptable salt, solvate, or solvate of the salt; wherein the subscript n is 1 to 3; the subscript m is 2 to 5 Ab is an anti-CD123 intact antibody or antigen binding fragment thereof comprising a heavy chain variable region having the amino acid sequence set forth in SEQ ID NO:1; and a light chain variable region having the amino acid sequence set forth in SEQ ID NO:2; and the subscript p is an integer from 1 to 4; and the average drug load of the composition is about 2. In a fourth aspect, the invention provides an anti-CD123 intact antibody or antigen binding fragment thereof comprising a heavy chain variable region having the amino acid sequence set forth in SEQ ID NO:1; and a light chain variable region having the amino acid sequence set forth in SEQ ID NO:2. In a fifth aspect, the invention provides use of the pharmaceutical composition of the second aspect for the manufacture of a medicament for treating a human patient having a cancer that expresses CD123 In a sixth aspect, the invention provides a pharmaceutical composition comprising the intact antibody or antigen binding fragment thereof of the fourth aspect conjugated to a cytotoxic agent. In a seventh aspect, the invention provides an anti-CD123 intact antibody or antigen binding fragment thereof comprising a heavy chain variable region having the amino acid sequence set forth in SEQ ID NO:1 provided that H20 is occupied by M or V, H38 is occupied by K or R, H48 is occupied by I, H66 is occupied by K or R, H67 is occupied by A, H69 is occupied by L, H71 is occupied by V, H73 is occupied by R, H81 is occupied by E or H, H82A is occupied by S or N, and H93 is occupied by T; ; and a light chain variable region having the amino acid sequence set forth in SEQ ID NO:2 provided that L2 is occupied by F, L19 is occupied by A or V, L21 is occupied by I or M, L22 is occupied by N or S, L38 is occupied by L. In an eighth aspect, the invention provides a pharmaceutical composition comprising the intact antibody or antigen binding fragment thereof of the seventh aspect conjugated to a cytotoxic agent. Preferred anti-CD123 antibodies are chimeric or humanized forms of the murine 7G3 antibody (Sun et al., Blood, 1996, 87(1):83-92). The murine 7G3 antibody comprises a heavy chain variable region having the amino acid sequence set forth in SEQ ID NO:8 and a light chain variable region having the amino acid sequence set forth in SEQ ID NO:9. Preferred humanized 7G3 antibodies for use herein are antibodies constructed using the human germline sequence hIGHv1-2 and J exon J -1 for the heavy chain variable region and the human germline sequence hIGKv4-1 and J exon J -2 for the light chain variable regions. Particularly preferred humanized 7G3 antibodies comprise the heavy chain variable region set forth in SEQ ID NO:1 and the light chain variable region set forth in SEQ ID NO:2. Antibodies for use in the present invention can be intact antibodies or antigen binding fragments thereof. The humanized 7G3 antibody can have a mature heavy chain variable region that is fused to a heavy chain constant region and a mature light chain variable region that is fused to a light chain constant region. The heavy chain constant region can be a naturally occurring or mutant form of a human constant region (e.g., SEQ ID NO:5, a heavy chain IgG1 constant region with cysteine substituting for serine at position 239, (S239C) or SEQ ID NO:6) . The heavy chain constant region can be of IgG1 isotype. An exemplary light chain constant region amino acid sequence is set forth in SEQ ID NO:7 The chimeric or humanized 7G3 antibodies described herein are conjugated to drug-linkers, including PBD drug-linkers to provide CD123 antibody-drug conjugates. Attachment can be via conventional or site specific conjugation methods. An exemplary attachment is via an engineered cysteine at position 239 of the heavy chain constant region, according to the EU index as set forth in Kabat. The CD123 directed antibody- drug conjugates are used to treat CD123 expressing disease, including CD123 expressing cancers, such as AML. In other embodiments, the chimeric or humanized 7G3 antibodies described herein are conjugated to drug-linkers, including glucuronide-pegylated MMAE drug- linkers to provide CD123 antibody-drug conjugates. In a further embodiment, the drug-linker attached to the humanized 7G3 antibody has the formula: or a pharmaceutically acceptable salt thereof wherein Z represents an organic moiety having a reactive site capable of reacting with a functional group on the antibody to form a covalent attachment thereto, n ranges from 8 to 36, R is hydrogen or a protecting group, R is a capping unit for the polyethylene glycol moiety. In some embodiments of this disclosure, the value n can range from 8 to 14. In other embodiment of this disclosure, the value n ranges from 10 to 12. In a further embodiment of this disclosure, the value of n is 12. In another embodiment, R is –CH or –CH CH CO H. 2 2 2
NZ736728A 2016-06-09 Cd123 antibodies and conjugates thereof NZ736728B2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201562175121P 2015-06-12 2015-06-12
PCT/US2016/036631 WO2016201065A1 (en) 2015-06-12 2016-06-09 Cd123 antibodies and conjugates thereof

Publications (2)

Publication Number Publication Date
NZ736728A NZ736728A (en) 2024-03-22
NZ736728B2 true NZ736728B2 (en) 2024-06-25

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