WO2025054524A1

WO2025054524A1 - Method for diagnosing amyloid diseases

Info

Publication number: WO2025054524A1
Application number: PCT/US2024/045688
Authority: WO
Inventors: Jonathan S. Wall; Emily Brooke MARTIN-SHULER
Original assignee: University of Tennessee Research Foundation
Current assignee: University of Tennessee Research Foundation
Priority date: 2023-09-07
Filing date: 2024-09-06
Publication date: 2025-03-13
Anticipated expiration: 2026-03-07

Abstract

The present disclosure relates in some aspects to methods and compositions for detecting an amyloid-related disease in an individual.

Description

METHOD FOR DIAGNOSING AMYLOID DISEASES

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application No. 63/581,213, filed on September 7, 2023, and U.S. Provisional Application No. 63/657,715, filed on June 7, 2024, which are hereby incorporated by reference in its entirety

REFERENCE TO AN ELECTRONIC SEQUENCE LISTING

[0002] The contents of the electronic sequence listing (165992001240SEQLIST.xml; Size: 40,979 bytes; and Date of Creation: September 6, 2024) is herein incorporated by reference in its entirety..

FIELD

[0003] The present disclosure relates in some aspects to methods of diagnosing amyloid-related diseases.

BACKGROUND

[0004] Systemic amyloidosis is a progressive protein misfolding disorder characterized by the extracellular deposition of proteinaceous fibrils, extracellular matrix components, and serum proteins. Accumulation of amyloid, notably within the heart and kidneys, the most affected organs in all types of amyloidosis, leads to organ dysfunction, poor quality of life, and ultimately death. Approximately 20 different proteins have been identified as fibrillar components in systemic amyloidosis (Aimo A, Merlo M, Porcari A, et al. Eur J Heart Fail. 2022); however, patients with variant or wild type transthyretin- (ATTRv and ATTRwt), immunoglobulin light chain- (AL), and leukocyte chemotactic factor 2- (ALECT2) associated amyloidosis comprise more than 90% of the cases diagnosed in the US (Edwards CV, Rao N, Bhutani D, et al. Blood. 2021;138:2632-2641).

[0005] Cardiac amyloidosis is an ominous manifestation in both AL and ATTR- associated amyloidosis causing restrictive hypertrophic cardiomyopathy, notably of the left ventricular wall and interventricular septum, accompanied by abnormalities of electrical conduction and strain (Garcia-Pavia P, Aus Dem Siepen F, Donal E, et al. N Engl J Med. 2023:NEJMoa2303765). However, any organ or tissue may be involved, resulting in heterogeneous clinical presentation and rendering accurate and rapid diagnosis challenging (Dorbala S, Cuddy S, Falk RH. JACC Cardiovasc Imaging. 2020;13:1368-1383).

[0006] Non-invasive imaging is particularly useful in the diagnostic algorithm for cardiac amyloidosis (Dorbala S, Park M-A, Cuddy S, et al. J Nucl Med. 2021;62:716-722). Echocardiography and cardiac magnetic resonance imaging (CMR) can reveal structural abnormalities and functional sequelae associated with amyloidosis 10; however, these techniques are not amyloid specific. Nuclear imaging with "^mTc-pyrophosphate (^99mTc-PyP) or "^mTc-3,3- diphosphono-l,2-propanodicarboxylic acid (DPD) is routinely used for diagnosing cardiac ATTR amyloidosis. These bone-seeking agents bind cardiac microcalcifications associated with cardiac amyloid and preferentially detect only ATTR-associated cardiac amyloidosis (Antoni G, Eubberink M, Estrada S, et al. J Nucl Med. 2013;54:213-220). In some aspects, existing methods are limited by the unavailability of amyloid specific measures to monitor change in amyloid load over time. Thus, a non-invasive and quantitative measure to detect and monitor cardiac, as well as extracardiac, amyloid deposits would be clinically beneficial. Provided herein are methods and compositions that address such and other needs.

SUMMARY

[0007] In one aspect, provided herein is a method of diagnosing an amyloid-related disease at an early stage in an individual at risk for developing the amyloid-related disease comprising a) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b) detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid-related disease, wherein the amyloid- related disease is in an early stage of the amyloid-related disease.

[0008] In some embodiments, the individual is determined to be at risk for an amyloid-related disease based upon the presence of a genetic mutation, having multiple myeloma, having amyloid positive laminectomy tissue, having an amyloid positive tissue from carpal tunnel release surgery, having a monoclonal gammopathy of unknown significance (MGUS), having heart failure with preserved ejection fraction (HFpEF), having heart failure with reduced ejection fraction (HFrEF), being from susceptible ethnic populations, or being elderly. In some embodiments, the genetic mutation is in the transthyretin protein. In some embodiments, the genetic mutation is in the fibrinogen ex protein.

[0009] In some embodiments, the individual does not have symptoms of amyloidosis. In some embodiments, the individual has neuropathic symptoms of an amyloid disease. In some embodiments, the individual has previously been diagnosed as not having an amyloid related disease.

[0010] In another aspect, provided herein is a method of diagnosing an amyloid- related disease at an early stage in an individual suspected of having an amyloid-related disease comprising a) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b) detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid-related disease, wherein the amyloid- related disease is in an early stage of the amyloid-related disease.

[0011] In another aspect, provided herein is a method of determining prognosis of an individual having an amyloid-related disease at an early stage comprising a) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloidreactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; and c) comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time to determine the prognosis of the individual, wherein the amyloid-related disease is in an early stage of the amyloid-related disease.

[0012] In some embodiments, the prognosis of an individual having an amyloid- related disease is based on detecting an amount of amyloid-reactive peptide in the heart alone. In some embodiments, the prognosis of an individual having an amyloid-related disease is based on detecting an amount of amyloid-reactive peptide in the heart and kidneys. In some embodiments, the prognosis of an individual having an amyloid-related disease is based on detecting an amount of amyloid-reactive peptide in the heart, kidneys, and all other organs.

[0013] In another aspect, provided herein is a method of treating an amyloid-related disease in an individual with the amyloid-related disease at an early stage comprising a) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; b) detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label in a tissue or organ of the individual, and c) administering a treatment for the amyloid-related disease if the amount of amyloid-reactive peptide is above a threshold.

[0014] In some embodiments, the individual is suspected of having the amyloid- related disease.

[0015] In another aspect, provided herein is a method of monitoring treatment of an amyloid-related disease in an individual with the amyloid-related disease at an early stage comprising a) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b) administering a treatment for an amyloid-related disease; c) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; and d) comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time to determine whether the treatment is effective.

[0016] In some embodiments, the method further comprises administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloidreactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time, optionally a third time a fourth time, and/or a fifth time.

[0017] In some embodiments, the first time and the second time are at least six weeks apart. [0018] In another aspect, provided herein is a method of selecting a treatment for an amyloid-related disease in an individual comprising a) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b) detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein if amyloid is detected in the heart a treatment for the amyloid-related disease is administered and wherein if amyloid is not detected in the heart, an alternative therapy is administered. ‘

[0019] In another aspect, provided herein is a method of managing the treatment for an amyloid-related disease in an individual comprising a) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b) administering a treatment for an amyloid- related disease; c) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; d) comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time; and e) adjusting the treatment for the amyloid-related disease.

[0020] In some embodiments, if the amyloid disease is stable between the first and second times treatment is be modified. In some embodiments, if the amyloid burden increases treatment is reinitiated.

[0021] In some embodiments, the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid-related disease. In some embodiments, the amyloid-related disease is in an early stage of the amyloid-related disease.

[0022] In some embodiments, the amyloid-reactive peptide comprises SEQ ID NO:13.

[0023] In some embodiments, the detectable label is a radiolabel. In some embodiments, the detectable label is selected from the group consisting of ⁿC, ¹⁸F, ⁱⁿIn, "^mTc, ⁸⁹Zr, ⁶⁸Ga, and ¹²³I, ¹²⁴I, and ¹²⁵I. In some embodiments, the detectable label is ¹²⁴I. [0024] In some embodiments, the method further comprises administering a dose of about 0.1 to about 25 mCi of ¹²⁴I-labeled amyloid-reactive peptide to the individual. In some embodiments, the method further comprises administering a dose of about 0.3 mCi, 1 mCi, or about 2 mCi of ¹²⁴I-labeled amyloid-reactive peptide to the individual. In some embodiments, the method further comprises administering a dose of about of aboutl mCi (±10%) of ¹²⁴I-labeled amyloid-reactive peptide to the individual.

[0025] In some embodiments, the method further comprises administering a dose of about 20 mCi of Tc-99 to the individual.

[0026] In some embodiments, the method further comprises administering about 0.3 mg, 1 mg, 1.5 mg, or about 2 mg of amyloid-reactive peptide to the individual.

[0027] In some embodiments, the amyloid-reactive peptide is administered intravenously.

[0028] In some embodiments, the method further comprises determining an organspecific standard uptake value ratio for an organ within an individual. In some embodiments, the organ- specific SUVR for the individual is selected from the group consisting of SUVR mean, SUVR max, and SUVR peak.

[0029] In some embodiments, the method further comprises determining an organspecific SUV for the individual. In some embodiments, the organ- specific SUV for the individual is selected from the group consisting of SUV mean, SUV max, and SUV peak.

[0030] In some embodiments, the method further comprises determining an organspecific percent injected dose/gram (%ID) for the individual.

[0031] In some embodiments, the sensitivity for detecting amyloid using the amyloid-reactive peptide is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 99% or at least 100%. In some embodiments, the sensitivity is about 99% or about 100%.

[0032] In some embodiments, the specificity of the amyloid-reactive peptide is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 99% or at least 100%. In some embodiments, the specificity of the amyloidreactive peptide is about 99% or 100%.

[0033] In some embodiments, the method further comprises determining one or more health related quality of life measures for the individual. [0034] In some embodiments, the method further comprises detecting one or more biomarkers associated with the amyloid-related disease. In some embodiments, the biomarker associated with amyloid-related disease is selected from the group consisting of Troponin T, NTproBNP, urine protein levels, UACR, EGFR, and alkaline phosphatase levels.

[0035] In some embodiments, the tissue or organ of the individual is selected from the group consisting of lung, fat, heart, kidney, pancreas, joints, spine, liver, spleen, adrenal gland, bone lesions, choroid plexus, pituitary gland, uterus, bone marrow, musculoskeletal tissue, gastrointestinal, and prostate gland.

[0036] In some embodiments, the threshold is an SUVR mean threshold value. In some embodiments, the SUVR mean threshold value is approximately 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, or 1.6 if the organ or tissue is the liver, the SUVR mean threshold value is approximately 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, or 1.5 if the organ or tissue is the spleen, the SUVR mean threshold value is approximately 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, or 2.3 if the organ or tissue is the kidneys, the SUVR mean threshold value is approximately 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, or 1.7 if the organ or tissue is the pancreas, the SUVR mean threshold value is approximately 0.9, 1.0, 1.1, 1.2, 1.3,

1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, or 2.1 if the organ or tissue is the heart or the SUVR mean threshold value is approximately 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, or 1.4 if the organ or tissue is the adrenal gland. In some embodiments, the SUVR mean threshold value is 1.31 if the organ or tissue is the liver, the SUVR mean threshold value is 1.21 if the organ or tissue is the spleen, the SUVR mean threshold value is 1.88 if the organ or tissue is the kidneys, the SUVR mean threshold value is 1.40 if the organ or tissue is the pancreas, the SUVR mean threshold value is 1.19 if the organ or tissue is the heart or the SUVR mean threshold value is 1.35 if the organ or tissue is the adrenal gland.

[0037] In some embodiments, the threshold is an SUVR max threshold value. In some embodiments, the SUVR max threshold value is 10.6, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, or 16 if the organ or tissue is the liver, the SUVR max threshold value is 3.8, 4, 4.5, 5,

5.5, or 5.9 if the organ or tissue is the spleen, the SUVR max threshold value is 7.7, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, or 11.7 if the organ or tissue is the kidneys, the SUVR max threshold value is

7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, or 11.4 if the organ or tissue is the pancreas, the SUVR max threshold value is 4.9, 5, 5.5, 6, 6.5, 7, or 7.5 if the organ or tissue is the heart or the SUVR max threshold value is 1, 1.1, 1.2, 1.3, 1.4, 1.5, or 1.6 if the organ or tissue is the adrenal gland. In some embodiments, the SUVR max threshold value is 13.26 if the organ or tissue is the liver, the SUVR max threshold value is 4.86 if the organ or tissue is the spleen, the SUVR max threshold value is 9.68 if the organ or tissue is the kidneys, the SUVR max threshold value is 9.48 if the organ or tissue is the pancreas, the SUVR max threshold value is 6.20 if the organ or tissue is the heart or the SUVR max threshold value is 1.31 if the organ or tissue is the adrenal gland.

[0038] In some embodiments, the method further comprises performing a cardiac biopsy if amyloid is detected in the heart. In some embodiments, the method further comprises performing additional amyloid imaging on the individual. In some embodiments, the method further comprises performing additional amyloid imaging on the individual before administering the amyloid reactive peptide. In some embodiments, the additional amyloid imaging on the individual comprises ECHO, CMR, bone scintigraphy or positron emission tomography imaging. In some embodiments, the additional amyloid imaging on the individual further comprises a tracer selected from the group consisting of "^mTc-PyP, "^mTc-DPD, "^mTc-HMDP, "^mTc-MDP other bone scintigraphy tracers, ¹²⁴I, and ¹⁸F-florbetapir, ¹⁸F-flutemetamol, and ¹⁸F-florbetaben.

[0039] In some embodiments, the diagnosis, prognosis, or response, is confirmed by a measure of the health-related quality of life of the individual, the presence or amount of one or more biomarkers associated with the amyloid-related disease, a cardiac biopsy, and/or additional amyloid imaging of the individual.

[0040] In some embodiments, the individual is diagnosed with amyloid cardiomyopathy. In some embodiments, the individual is suspected of having amyloid cardiomyopathy .

[0041] In some embodiments, the amyloid-related disease is systemic or localized amyloidosis. In some embodiments, the amyloid-related disease is cardiac amyloidosis.

[0042] In some embodiments, the amyloid-reactive peptide has pan-amyloid specificity. In some embodiments, the amyloid-reactive peptide binds to amyloid of immunoglobulin light chain (AE), immunoglobulin heavy chain (AH), p2-microglobulin (Ap2M), transthyretin (ATTR wild type; ATTR variant), apolipoprotein Al (AApoAI), apolipoprotein All (AApoAII), apolipoprotein AIV (AApoAIV), gelsolin (AGel), apolipoprotein C-II (AApoCII), apolipoprotein C-II (AApoCIII), lysozyme (AEys), leukocyte chemotactic factor (AEECT2), fibrinogen a variants (AFib), cystatin variants (ACys), calcitonin (ACal), lactadherin (AMed), islet amyloid polypeptide (AIAPP), prolactin (APro), insulin (Alns), prior protein (APrP); a-synuclein (AaSyn), tau (ATau), atrial natriuretic factor (AANF), IAAP, ALP4, or ALpi.

[0043] In some embodiments, the amyloid reactive peptide is detected using PET, PET/CT, gamma scintigraphy, SPECT, and/or SPECT/CT.

[0044] In some embodiments, the amyloid-related disease is selected from the group consisting of AL, AH, Ap2M, ATTRv, ATTRwt, AA, AApoAI, AApoAII, AApoCII, AApoCIII, AGel, ALys, ALECT2, AFib, ACys, ACal, AMed, AIAPP, APro, Alns, APrP, and Ap amyloidosis. In some embodiments, the amyloid-related disease is cardiac AL amyloidosis. In some embodiments, the amyloid-related disease is cardiac ATTR amyloidosis.

[0045] In some embodiments, the individual has a genetic predisposition to an amyloid-related disease. In some embodiments, the individual has a family history of an amyloid-related disease.

[0046] In some embodiments, the individual is elderly.

[0047] In some embodiments, the individual has an early stage of an amyloid-related disease. In some embodiments, the individual has an early stage of an systemic amyloidosis. In some embodiments, the individual has an early stage of cardiac amyloidosis. In some embodiments, the individual has an early stage of AL amyloidosis. In some embodiments, the early stage of AL amyloidosis is diagnosed according to the Mayo Clinic system. In some embodiments, the early stage of AL amyloidosis is stage 1 AL amyloidosis. In some embodiments, the individual has an early stage of ATTR amyloidosis. In some embodiments, the early stage of ATTR amyloidosis comprises stage 1 ATTR amyloidosis.

[0048] In some embodiments, the method further comprises administering a treatment for the amyloid-related disease. In some embodiments, the treatment for the amyloid- related disease is selected from the group consisting of transthyretin stabilizers (e.g. tafamidis, acoramidis), transthyretin silencers (e.g. Patisiran, Inotersen, Vutrisiran, Eploetersen), gene editing approaches, anti-amyloid approaches utilizing monoclonal antibodies, treatments targeting plasma cell clones (e.g. Daratumumab, Bortezomib), and an antibody-peptide fusion comprising an antibody-peptide fusion protein comprising a second amyloid-reactive peptide and an antibody that binds to amyloid fibrils. In some embodiments, the second amyloid-reactive peptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1-14 comprising 0, 1, 2, 3, or 4 amino acid substitutions, insertions, or deletions. In some embodiments, the antibody-peptide fusion protein comprises a heavy chain and a light chain and wherein the amyloid-reactive peptide is linked to at the C-terminal end of the light chain of the antibody via a spacer. In some embodiments, the antibody-peptide fusion protein comprises: (i) an amyloid-reactive peptide comprising the amino acid sequence set forth in SEQ ID NO: 2; and (ii) an antibody that binds to a human amyloid fibril, wherein the antibody comprises a heavy chain and a light chain, wherein the heavy chain of the antibody comprises a heavy chain variable region (VH) and the light chain of the antibody comprises a light chain variable region (VL), wherein the VH comprises a CDR-H1 comprising the amino acid sequence set forth in SEQ ID NO: 106, a CDR-H2 comprising the amino acid sequence set forth in SEQ ID NO: 107, and a CDR-H3 comprising the amino acid sequence set forth in SEQ ID NO: 108, and the VL comprises a CDR-L1 comprising the amino acid sequence set forth in SEQ ID NO: 103, a CDR- L2 comprising the amino acid sequence set forth in SEQ ID NO: 104, and a CDR-L3 comprising the amino acid sequence set forth in SEQ ID NO: 105; wherein the amyloid-reactive peptide and antibody are linked at the C-terminal end of the light chain, and wherein the amyloid-reactive peptide is linked to the antibody via a spacer comprising an amino acid sequence set forth in SEQ ID NO: 83.

[0049] In some embodiments, a peptide comprising the amyloid-reactive peptide and an N-terminal leader sequence is administered to the individual. In some embodiments, the peptide comprising the amyloid reactive peptide comprises the amino acid sequence set forth in SEQ ID NO: 100.

[0050] In some embodiments, a detectable label is bound to one or more amino acids at positions 1 to 6 of the amino acid sequence set forth in SEQ ID NO: 100. In some embodiments, the detectable label is ¹²⁴I. In some embodiments, the ¹²⁴I is bound to amino acid 4 of SEQ ID NO: 100.

[0051] In some embodiments, the method further comprises administering potassium iodide to the individual. In some embodiments, the administering potassium iodide comprises administering 130 mg of the potassium iodide to the patient for seven days starting one day before the administration of the amyloid reactive peptide. In some embodiments, the administering potassium iodide comprises administering 130 mg of the potassium iodide to the patient for three days starting about 30 minutes before the administration of the amyloid reactive peptide. In some embodiments, the administration of potassium iodide is oral administration. [0052] In another aspect, provided herein is a peptide comprising the amino acid set forth in SEQ ID NO: 100, wherein the peptide comprises a detectable label bound to one or more amino acids at positions 1 to 6. In some embodiments, the detectable label is ¹²⁴I. In some embodiments, the ¹²⁴I is bound to amino acid 4 of SEQ ID NO: 100.

BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The drawings illustrate certain features and advantages of this disclosure. These embodiments are not intended to limit the scope of the appended claims in any manner.

[0054] FIG. 1 depicts a multi-part, open-label study to assess the safety, dosimetry and biodistribution of ¹²⁴I-p5+14 peptide in patients with systemic amyloidosis of any type; pre- symptomatic subjects carrying a germline TTR mutation; and healthy subjects.

[0055] FIG. 2 depicts the biodistribution of radioactivity in healthy subjects. FIG. 2A shows maximum intensity projections of PET data acquired at 5 h post infusion for five healthy subjects. FIG. 2B shows transaxial PET/CT images of the heart in healthy subjects.

[0056] FIG. 3 depicts cardiac uptake of ¹²⁴I-p5+14 in patients with AL and ATTR- associated amyloidosis. FIG. 3A shows maximum intensity projections of PET data and coronal PET/CT images of the heart (image intensity set individually for optimal visualization). FIG. 3B shows transaxial PET/CT images of the heart in healthy subjects and patients with AL or ATTR amyloidosis with positive PET imaging (PET+) who were deemed positive (Clin+) or negative (Clin-) for cardiac amyloidosis in the medical record..

[0057] FIG. 4 depicts PET evaluation of cardiac ¹²⁴I-p5+14 SUVRmean and correlation with serum NTproBNP. FIG. 4A shows the comparison of cardiac SUVRmean for patients with AL, ATTR, other types of amyloidosis and healthy susbjects. Cardiac SUVRmean values were also compared for PET positive and PET negative AL and ATTR patients. FIGs. 4B-4C depicts the significant positive correlation between Cardiac SUVRmean and serum NTproBNP in AL patients (FIG. 4B) which is not significant in ATTR patients (FIG. 4C). FIG. 4D shows the correlation between cardiac SUVRmean scaled by the serum creatinine for each patient and serum NTproBNP in AL patients.

[0058] FIGs. 5A-5B depict extracardiac uptake of ¹²⁴I-p5+14 in patients with AL or ATTR-associated amyloidosis. Uptake of ¹²⁴I-p5+14 in the lung, fat, kidney, pancreas, joints, and spine of ATTR amyloidosis patients (FIG. 5A), and the liver, spleen, kidney, adrenal gland, bone lesions, choroid plexus, pituitary gland, bone marrow, and pancreas of AL amyloidosis patients and a patient with multiple myeloma and amyloidosis (FIG. 5B).

[0059] FIG. 6 depicts automatic iso-contouring on ¹²⁴I-p5+14 PET images for quantifying cardiac uptake of radiotracer. LA: Left atrial. LV: Left ventricular. PET/CT: Positron emission tomography /computed tomography. RV: Right ventricular. SD: Standard deviation. VOI: Volume of interest. %ID/mL: Percent injected dose by milliliter.

[0060] FIG. 7 depicts ¹²⁴I-p5+14 PET/CT in uptake in a patient with ATTRwt cardiomyopathy (CMP) who had with equivocal "^mPYP SPECT/CT. The individual presented with heart failure, preserved left ventricular ejection fraction, diastolic dysfunction grade 2, asymmetric hypertrophy, and impaired global longitudinal strain on echocardiogram. He had a history of surgery for bilateral carpal tunnel syndrome and lumbar stenosis, and had no evidence for abnormal immunoglobulin light chains. "^mTc-PYP SPECT/CT was equivocal (nondiagnostic) with Grade 1 uptake. Then, cardiac MRI showed diffuse late gadolinium enhancement. ATTRwt-CMP (NAC stage 2, Mayo stage 2) was confirmed by endomyocardial biopsy with mass spectrometry and normal TTR gene sequencing. ¹²⁴I-p5+14 PET/CT performed within 6 months showed definite myocardial uptake. NAC: National Amyloidosis Center. MRI: Magnetic resonance imaging. "^mTc-PYP SPECT/CT: "^mTc-pyrophosphate single-photon emission computed tomography/computed tomography.

[0061] FIG. 8 depicts ¹²⁴I-p5+14 uptake metrics. ¹²⁴I-p5+14 LV %ID, CAA, and TBR perfectly discriminated amyloid CMP cases from controls, but SUVmean did not. Uptake measurement and calculations are explained in the Methods section. Thresholds shown for high metrics were defined using Youden’s index. Between-group comparisons were made using Dunn’s test. CAA: Cardiac amyloid activity (SUV units x mL). LV: Left ventricular. SUV: Standardized uptake value. TBR: Target- to-background ratio. %ID: Percent injected dose.

[0062] FIG. 9 depicts ¹⁸F-Florbetapir uptake metrics. ¹⁸F-Florbetapir LV %ID and CAA perfectly discriminated amyloid CMP cases from controls, but SUVmean and TBR did not. Thresholds shown for high metrics were defined using Youden’s index. Between-group comparisons were made using Dunn’s test.

[0063] FIG. 10 depicts ¹²⁴I-p5+14 and ¹⁸F-Florbetapir uptake metrics in the same participants. ¹²⁴I-p5+14 and ¹⁸F-florbetapir imaging were obtained in the same participants (1 AL-CMP participant without 18F-florbetapir PET/CT is not included). LV %ID, SUVmean, and CAA were higher in ATTRwt-CMP with ¹²⁴I-p5+14. But LV TBR was higher with ¹⁸F- florbetapir in AL-CMP and ATTRwt-CMP. Uptake measurement and calculations are explained in the Methods section. P-values were obtained from paired Wilcoxon signed-rank test.

[0064] FIGs. 11A-11B depicts changes in ¹²⁴I-p5+14 uptake as measured by SUVRmean and NTproBNP for amyloidosis AL patients (FIG. 11A) and ATTR patients (FIG. 11B).

[0065] FIG. 12 depicts the relationship between percent change in NTproBNP and scaled percent change in cardiac SUVR changes for 19 amyloidosis patients with AL or ATTR.

[0066] FIGs 13A-13I depicts the relationship between anatomical and functional metrics with ¹²⁴Lp5+14 uptake in the heart as measured by SUVRmean for AL patients, ATTR, and all amyloidosis patients. Heart left ventricular wall thickness (LV) (Y axis) correlates with heart SUVRmean (X axis) in AL patients (FIG. 13A). Global longitudinal strain (GLS) (Y axis), a parameter reflecting left ventricular function, correlates with heart SUVRmean (X axis) in AL patients (FIG. 13B) Interventricular septum thickness (IVS) (Y axis) does not correlate with heart SUVRmean (X axis) in AL patients (FIG. 13C). Heart LV wall thickness (Y axis) correlates with heart SUVRmean (X axis) in ATTR patients (FIG. 13D). GLS (Y axis) does not correlate with heart SUVRmean (X axis) in ATTR patients (FIG. 13E) IVS thickness (Y axis) correlates with heart SUVRmean (X axis) in ATTR patients (FIG. 13F). Heart LV wall thickness (Y axis) correlates with heart SUVRmean (X axis) in amyloidosis patients (FIG. 13G). GLS (Y axis) correlates with heart SUVRmean (X axis) in amyloidosis patients (FIG. 13H). IVS thickness (Y axis) correlates with heart SUVRmean (X axis) in amyloidosis patients (FIG. 131)

DETAILED DESCRIPTION

[0067] All publications, comprising patent documents, scientific articles and databases, referred to in this application are incorporated by reference in their entirety for all purposes to the same extent as if each individual publication were individually incorporated by reference. If a definition set forth herein is contrary to or otherwise inconsistent with a definition set forth in the patents, applications, published applications and other publications that are herein incorporated by reference, the definition set forth herein prevails over the definition that is incorporated herein by reference.

[0068] The section headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described. I. OVERVIEW

[0069] Provided herein are methods for the diagnosis and treatment of amyloid disease. In some embodiments, the methods comprise administering an amyloid-reactive agent and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual. In some embodiments, the methods provided herein are capable of diagnosing an amyloid-related disease in an individual at risk of developing an amyloid-related disease. In some embodiments, the methods provided herein are capable of diagnosing an amyloid-related disease in an individual suspected of having an amyloid-related disease. In some embodiments, the methods provided herein are capable of determining the prognosis of an individual diagnosed with an amyloid-related disease. In some embodiments, the methods provided herein are capable of monitoring the treatment of an individual with an amyloid-related disease. In some embodiments, the methods provided herein are capable of selecting the treatment for an individual with an amyloid-related disease.

[0070] The rates of early mortality in newly diagnosed amyloid-related diseases suggest there continue to be significant delays in diagnosis (Muchtar E, Gertz MA, Kumar SK, el al. Blood. 2017;129(15):2111-2119). For example, nearly 20% of patients succumb to AL amyloidosis within 6 months of diagnosis, and this statistic has shown no improvement in 40 years, suggesting, that patients who are diagnosed at an advanced state cannot be helped despite major advances in therapy for this disease (Hasib Sidiqi, M, and Morie A Gertz. Blood cancer journal vol. 11,5 90. 15 May. 2021). Current anatomic imaging methods, including echocardiography and cardiac magnetic resonance imaging, provide valuable structural and functional information once a diagnosis of amyloidosis has been established. "^mTc-PyP and similar bone- seeking agents are used for detecting cardiac amyloid; however, their relationship with amyloid fibrils is not well understood. Therefore, a non-invasive imaging method using a reagent that directly binds amyloid deposits, is quantifiable, and can detect cardiac amyloidosis before the onset of overt anatomic changes and organ dysfunction would be of significant clinical benefit.

[0071] In some embodiments, provided herein are methods of diagnosing an amyloid-related disease in an individual at risk for developing the amyloid-related disease comprising administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid disease.

[0072] Also provided herein, in some embodiments, are methods of treating an amyloid-related disease comprising administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label in a tissue or organ of the individual, and administering a treatment for the amyloid-related disease if the amount of amyloid-reactive peptide is above a threshold.

II. DEFINITIONS

[0073] As used herein, an “amino acid” or “amino acid residue” refers to any naturally occurring amino acid, any non-naturally occurring amino acid, any modified including derivatized amino acid, or any amino acid mimetic known in the art. The amino acid may be referred by both their common three letter abbreviation and single letter abbreviation.

[0074] The terms amyloids, amyloid deposits, amyloid fibrils, and amyloid fibers refer to insoluble fibrous protein aggregates sharing specific structural traits. The protein aggregates have a tertiary structure, for example, that is formed by aggregation of any of several different proteins and that consists of an ordered arrangement of P sheets stacked perpendicular to a fiber axis. See Sunde et al., J. Mol. Biol. (1997) 273:729-39. Abnormal accumulation of amyloids in organs may lead to amyloidosis. Although they are diverse in their occurrence, all amyloids have common morphologic properties in that they stain with specific dyes such as Congo red and have a characteristic red-green birefringent appearance in polarized light after staining. Amyloids also share common ultrastructural features and common x-ray diffraction and infrared spectra.

[0075] Amyloidosis refers to a pathological condition or disease characterized by the presence of amyloids, such as the presence of amyloid deposits. “Amyloid diseases” or “amyloidosis” are diseases associated with the formation, deposition, accumulation or persistence of amyloid fibrils. Such diseases include, but are not limited to, Alzheimer’s disease, Down's syndrome, hereditary cerebral hemorrhage with amyloidosis of the Dutch type, and cerebral beta-amyloid angiopathy. Other amyloid diseases such as systemic AA amyloidosis, AL amyloidosis, ATTR amyloidosis, ALECT2 amyloidosis, and IAPP amyloidosis of type II diabetes are also amyloid diseases.

[0076] The term “amyloidogenic” refers to producing or tendency to produce amyloid deposits. For example, certain soluble monomeric proteins can undergo extensive conformational changes leading to their aggregation into well-ordered, unbranching, 8- to 10-nm wide fibrils, which culminate in the formation of amyloid aggregates. More than thirty proteins, for example, have been found to form amyloid deposits (or amyloids) in man. Not all proteins within the class of diverse proteins, such as immunoglobulin light chains, are capable of forming amyloid, i.e., some immunoglobulin light chains are non- amyloidogenic, meaning that they do not tend to form amyloids. Other proteins of the class, however, can form amyloid deposits and are thus amyloidogenic. Furthermore, within the class of light chain proteins, some may be deemed more “amyloidogenic” than others based upon the ease with which they form amyloid fibrils. Certain light chain proteins are deemed non-amyloidogenic or less amyloidogenic because of their inability to readily form amyloid fibrils in patients or in vitro.

[0077] As used herein, the term “carriers” includes pharmaceutically acceptable carriers, excipients, or stabilizers which are nontoxic to the cell, tissue, mammal, or subject being exposed thereto at the dosages and concentrations employed. Often the pharmaceutically acceptable carrier is an aqueous pH buffered solution. Examples of pharmaceutically acceptable carriers include without limitation buffers such as phosphate, citrate, and other organic acids; antioxidants including ascorbic acid; low molecular weight (less than about 10 residues) polypeptide; proteins, such as serum albumin, gelatin, or immunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone; amino acids such as glycine, glutamine, asparagine, arginine or lysine; monosaccharides, disaccharides, and other carbohydrates including glucose, mannose, or dextrins; chelating agents such as EDTA; sugar alcohols such as mannitol or sorbitol; salt-forming counterions such as sodium; and/or nonionic surfactants such as Tween®, polyethylene glycol (PEG), and Pluronics®.

[0078] As used herein, the term “effective amount” or “suitable amount” is an amount sufficient to effect beneficial or desired clinical or biochemical results. An effective amount can be administered one or more times. For purposes of this invention, an effective amount of an amyloid reactive agent or detection is an amount that is sufficient to bind to and allow detection of amyloids. [0079] As used herein, the term “imaging agent” or “contrast agent” which terms may be used interchangeably, refers to any agent which may be used in connection with methods for imaging an internal region of a subject and/or diagnosing the presence or absence of a disease in a subject by the application and/or detection of an energy source. Exemplary imaging agents include contrast agents for use in connection with ultrasound, magnetic resonance imaging, radionuclide imaging, or x-ray (including computed tomography) imaging of a patient, and the compositions described herein.

[0080] As used herein, the term “mammal” for purposes of the present invention refers to any animal classified as a mammal, including humans, domestic and farm animals, and zoo, sports, or pet animals, such as dogs, cats, cattle, horses, sheep, pigs, and so on. In some embodiments, the mammal is human.

[0081] As used herein, the term “peptide” refers to any peptide or peptidomimetic structure comprising or consisting of two or more amino acids, including chemical modifications and derivatives of amino acids.

[0082] As used herein, the term “purified” or “isolated” molecule refers to biological or synthetic molecules that are removed from their natural environment and are isolated or separated and are free from other components with which they are naturally associated.

[0083] As used herein, the term “specifically binds” refers to a non-random binding reaction between two molecules, for example between an amyloid-reactive agent and an amyloid. The term “specifically binds” may be used interchangeably with “selectively targets” or “selectively associates.”

[0084] As used herein, the term “selectively targets” or “selectively associates” with reference to amyloids, refers to, for example, the selective localization or binding between an amyloid-reactive agent and an amyloid compared to a non-amyloid protein. An amyloid-reactive agent can selectively target multiple types of amyloid.

[0085] As used herein, the term “subject” refers to a vertebrate. The vertebrate may be a mammal, for example, a human. The subject may be a human patient.

[0086] As used here, the term “amyloid-reactive agent” is an agent that specifically reacts with or binds to amyloid.

[0087] As used herein, the term “conjugated” includes covalent and non-covalent binding. [0088] The term "antibody" herein is used in the broadest sense and specifically covers monoclonal antibodies (including full length monoclonal antibodies), polyclonal antibodies, multispecific antibodies (e.g., bispecific antibodies), and antibody fragments so long as they exhibit the desired biological activity.

[0089] =The term “amyloid reactive peptide” refers to a peptide that binds to any of various amyloid fibrils such as, but not limited to, amyloidogenic X6 variable domain protein (VX6Wil) or an amyloidogenic immunoglobulin light chain (AL), A[3( I -40) amyloid-like fibril or an amyloidogenic AP precursor protein, or serum amyloid protein A (AA). In other embodiments, the amyloids bound by the amyloid - reactive peptide comprise amyloidogenic forms of immunoglobulin heavy chain (AH), p2-microglobulin (Ap2M), transthyretin variants (ATTRv), wild type transthyretin (ATTRwt), apolipoprotein Al (AApoAI), apolipoprotein All (AApoAII), gelsolin (AGel), lysozyme (ALys), leukocyte chemotactic factor (ALect2), fibrinogen ex variants (AFib), cystatin variants (ACys), calcitonin ((ACal), lactadherin (AMed), islet amyloid polypeptide (AIAPP), prolactin (APro), insulin (Alns), prior protein (APrP); cx- synuclein (AaSyn), tau (ATau), atrial natriuretic factor (AANF), or IAAP, ALK, AL/ other amyloidogenic peptides.

IL METHODS OF DIAGNOSIS

[0090] Provided herein are methods of diagnosing an amyloid-related disease in an individual at risk for developing the amyloid-related disease comprising administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and detecting an amount of amyloidreactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid disease.

[0091] Provided herein are methods of diagnosing an amyloid-related disease at an early stage in an individual comprising administering an amyloid-reactive peptide conjugated to a detectable label to the individual and detecting the amount of detectable label in a tissue or organ of the individual, wherein the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid-related disease, wherein the amyloid-related disease is in an early stage of the amyloid-related disease. In some embodiments, the amyloid- related disease is systemic amyloidosis. In some embodiments, the amyloid-related disease is cardiac amyloidosis. In some embodiments, the amyloid-reactive peptide conjugated to a detectable label is a peptide comprising the amino acids set forth in SEQ ID NO: 100, conjugated to ¹²⁴I. In some embodiments, the ¹²⁴I is bound to amino acid 4 of SEQ ID NO: 100.

[0092] The methods provided herein can be used for diagnosing an amyloid-related disease at an early stage. In some embodiments, the methods can be used to diagnose an amyloid-related disease before traditional diagnostic methods. In some embodiments, the individual has previously been diagnosed as not having a amyloid-related disease. In some embodiments, the methods have high sensitivity and specificity for diagnosing amyloid-related diseases at an early stage. A. Amyloid-reactive peptides

[0093] In some embodiments, the methods for diagnosing a type of amyloid disease comprise administering an amyloid-reactive peptide conjugated to a detectable label.

[0094] In some embodiments, the methods for diagnosing a type of amyloid disease comprise administering an amyloid-reactive agent comprising an amyloid-reactive peptide conjugated to a detectable label. In some embodiments, the amyloid-reactive peptide comprises an amino acid sequence that is at least 80%, 85%, 90% or more identical to the amino acid sequence set forth as any one of SEQ ID NOS: 1-14, such as at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to the amino acid sequence set forth as any one of SEQ ID NOS: 1-14. In some embodiments, amyloid-reactive peptides used with the methods described herein comprise or consist of from about 10 to 55 amino acids. The amyloidreactive peptides of the present invention may, for example, comprise or consist of 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, or 55 amino acids. Such peptides are described, for example, in international patent application WO2016032949, which is hereby incorporated herein in its entirety. In some embodiments, the methods for diagnosing an amyloid disease comprise an amyloid-reactive peptide with an amino acid sequence as set forth in SEQ ID NO: 13. In some embodiments, the methods for diagnosing a type of amyloid disease comprise p5+14. In some embodiments, the methods for diagnosing an amyloid disease comprise an amyloid-reactive peptide with an amino acid sequence as set forth in SEQ ID NO: 13, conjugated to ¹²⁴I Table 1. Example Amyloid-Reactive Peptide Sequences

[0095] The amino acids forming all or a part of the amyloid-reactive peptides used with the present methods may be stereoisomers and modifications of naturally occurring amino acids, non-naturally occurring amino acids, post-translationally modified amino acids, enzymatically synthesized amino acids, derivatized amino acids, constructs or structures designed to mimic amino acids, and the like. The amino acids forming the peptides of the present invention may be one or more of the 20 common amino acids found in naturally occurring proteins, or one or more of the modified and unusual amino acids. The amyloid-reactive peptides used with the methods described herein may be made by any technique known to those of skill in the art, including chemical synthesis or recombinant means using standard molecular biological techniques. [0096] The peptides of the present invention may also comprise one or more modified amino acids. The modified amino acid may be a derivatized amino acid or a modified and unusual amino acid. Examples of modified and unusual amino acids include but are not limited to, 2- Aminoadipic acid (Aad), 3-Aminoadipic acid (Baad), P-Amino-propionic acid (Bala, P-alanine), 2-Aminobutyric acid (Abu, piperidinic acid), 4- Aminobutyric acid (4Abu), 6- Aminocaproic acid (Acp), 2-Aminoheptanoic acid (Ahe), 2-Aminoisobutyric acid (Aib), 3- Aminoisobutyric acid (Baib), 2-Aminopimelic acid (Apm), 2,4-Diaminobutyric acid (Dbu), Desmosine (Des), 2,2'-Diaminopimelic acid (Dpm), 2,3-Diaminopropionic acid (Dpr), N- Ethylglycine (EtGly), N-Ethylasparagine (EtAsn), Hydroxylysine (Hyl), allo-Hydroxylysine (AHyl), 3-Hydroxyproline (3Hyp), 4-Hydroxyproline (4Hyp), Isodesmosine (Ide), allo- Isoleucine (Alle), N-Methylglycine (MeGly, sarcosine), N-Methylisoleucine (Melle), 6-N- Methyllysine (MeLys), N-Methylvaline (MeVal), Norvaline (Nva), Norleucine (Nle), and Ornithine (Orn).

[0097] Other examples of modified and unusual amino acids are described generally in Synthetic Peptides: A User's Guide, Second Edition, April 2002, Edited Gregory A. Grant, Oxford University Press; Hruby V J, Al-obeidi F and Kazmierski W: Biochem J 268:249-262, 1990; and Toniolo C: Int J Peptide Protein Res 35:287-300, 1990; the teachings of all of which are incorporated herein by reference.

[0098] In certain embodiments, the peptides of the present invention may comprise or consist of the following amino acid sequence: SRAQRAQARQARQAQRAQRAQARQARQ. (SEQ ID NO: 17)

[0099] The peptides of the present invention may be a fusion protein comprising a second peptide as a leader sequence at the amino terminus, such as CGGY (SEQ ID NO: 18) or GGGYS (SEQ ID NO: 19) for labeling with an agent for detection. Accordingly, in some embodiments, the amyloid-reactive peptide may have at most 55 amino acids and comprise an amino acid sequence as set forth in CGGYSRAQRAQARQARQAQRAQRAQARQARQ. (SEQ ID NO: 20)

[0100] In some embodiments, provided herein is a peptide comprising an amyloid reactive peptide fused to an N-terminal leader sequence. In some embodiments, the leader sequence comprises the amino acid sequence GGGYS (SEQ ID NO: 19). In some embodiments, provided herein is a peptide comprising an amyloid reactive peptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 1-14 and the N-terminal leader sequence GGGYS. In some embodiments, provided herein is a peptide comprising the amino acid sequence GGGYS KAQKA QAKQA KQAQK AQKAQ AKQAK QAQKA QKAQA KQAKQ (SEQ ID NO: 100). In some embodiments, the peptide comprises the amino acid sequence set forth in SEQ ID NO: 100 and is conjugated to a detectable label. In some embodiments, the detectable label is bound to one or more of amino acids 1-6 of SEQ ID NO: 100. In some embodiments, the detectable label is bound to amino acids 4 of SEQ ID NO: 100. In some embodiments, the detectable label is bound to the N-terminal leader sequence. In some embodiments, the peptide comprises the amino acid sequence set forth in SEQ ID NO: 100 and is conjugated to a ¹²⁴I detectable label. In some embodiments, the ¹²⁴I detectable label is bound to one or more of amino acids 1-6 of SEQ ID NO: 100. In some embodiments, the ¹²⁴I detectable label is bound to amino acid 4 of SEQ ID NO: 100. In some embodiments, the detectable label is bound to the N-terminal.

[0101] The fusion protein may comprise other leader sequences such as a cell penetrating peptide (CPP) or a blood brain barrier (BBB) translocating peptide.

[0102] The present invention also provides other peptides and fusion proteins that are rich in positively charged amino acids for imaging amyloids.

[0103] The peptides of the present invention may be made by any technique known to those of skill in the art, including chemical synthesis, recombinant means using standard molecular biological techniques, or the isolation of peptides from natural sources. The peptides may be synthesized in solution or on a solid support in accordance with conventional techniques. Various automatic synthesizers are commercially available and can be used in accordance with known protocols. (See, for example, Stewart and Young, Solid Phase Peptide Synthesis, 2d ed. Pierce Chemical Co., 1984; Tam et al., J. Am. Chem. Soc., 105:6442, 1983; Merrifield, Science, 232: 341-347, 1986; and Barany and Merrifield, The Peptides, Gross and Meienhofer, eds., Academic Press, New York, pp. 1-284, 1979, each is incorporated herein by reference in its entirety.)

[0104] Alternatively, recombinant DNA technology may be employed wherein a nucleotide sequence which encodes a peptide of the invention is inserted into an expression vector, transformed or transfected into an appropriate host cell, cultivated under conditions suitable for expression, and isolating the peptide. [0105] In certain embodiments, amyloid reactive agent may be a naturally occurring peptide and may be obtained by isolation or purification from its natural sources. Protein purification techniques involve, at one level, the homogenization and crude fractionation of the cells, tissue or organ to peptide and non-peptide fractions. Other protein purification techniques include, for example, precipitation with ammonium sulfate, polyethylene glycol (PEG), antibodies and the like, or by heat denaturation, followed by: centrifugation; chromatography steps such as ion exchange, gel filtration, reverse phase, hydroxylapatite and affinity chromatography; isoelectric focusing; gel electrophoresis, for example polyacrylamide gel electrophoresis; and combinations of these and other techniques

[0106] Various chromatographic techniques include but are not limited to ionexchange chromatography, gel exclusion chromatography, affinity chromatography, immunoaffinity chromatography, and reverse phase chromatography. A particularly efficient method of purifying peptides is fast performance liquid chromatography (FPLC) or even high performance liquid chromatography (HPLC).

[0107] The order of conducting the various purification steps may be changed, or that certain steps may be omitted, and still result in a suitable method for the preparation of a substantially purified peptide. The peptides of the present invention may be a part of a polypeptide or protein and may be produced by biochemical or enzymatic fragmentation of the polypeptide or protein. Accordingly, the peptides of the present invention may be (a) naturally- occurring, (b) produced by chemical synthesis, (c) produced by recombinant DNA technology, (d) produced by biochemical or enzymatic fragmentation of larger molecules, (e) produced by methods resulting from a combination of methods a through d listed above, or (f) produced by any other means for producing peptides.

[0108] During chemical synthesis, the peptides may be modified at its N- or C- terminus, thereby providing for improved stability and formulation, resistance to protease degradation, and the like. Examples of modifications of amino acids include pegylation, acetylation, alkylation, formylation, amidation. Moreover, various amino acids which do not naturally occur along the chain may be introduced to improve the stability of the peptides.

[0109] Cysteine is also useful for facilitating the labeling of peptides of the present invention with biotin, fluorophores, or other ligands via conjugation. Moreover, a cysteine on the leader peptide allows the generation of covalently bound dimer molecules that might increase the relative affinity of the peptides for their targets.

B. Detectable labels

[0110] In some embodiments, the method for diagnosing a type of amyloid disease comprises administering an amyloid-reactive peptide conjugated to a detectable label. As used herein, conjugation may be covalent and/or non-covalent binding. In some embodiments, the detectable label is bound either covalently or non-covalently to the peptide. Without being limited, this may include radionuclides (e.g., C-l l, 1-125, 1-123, 1-131, Zr-89, Tc-99m, Cu-64, Br-76, F-18); enzymes (horse radish peroxidase); biotin; fluorophores, etc. Any means known in the art for detectably labeling a protein can be used and/or adapted for use with the methods described herein. For example, the amyloid-reactive peptides, can be radiolabeled with a radioisotope, or labeled with a fluorescent tag or a chemiluminescent tag. Example radioisotopes include, for example, ⁿC, ¹⁸F, ⁱⁿIn, "^mTc, and ¹²³I, ¹²⁴I, and ¹²⁵I. These and other radioisotopes can be incorporated to the amyloid-reactive agent or detection dye. Example fluorescent or chemiluminescent tags include fluorescein, Texas red, rhodamine, Alexa dyes, and luciferase that can be incorporated to the amyloid-reactive agent using conventional methods in the art.

[0111] In some embodiments, the methods for diagnosing a type of amyloid disease comprise administering an amyloid-reactive agent comprising a radiolabel. In some embodiments, the radiolabel is ⁿC, ¹⁸F, ^{n i}In, "mTc, ⁸⁹Zr and ¹²³I, ¹²⁴I, or ¹²⁵I. In some embodiments, the radiolabelled amyloid-reactive agent is a radiolabeled amyloid-reactive peptide. In some embodiments, the radiolabeled amyloid-reactive peptide is a ¹²⁴I-labelled amyloid-reactive peptide. In other embodiments, the method for diagnosing a type of amyloid disease comprise administering ¹²⁴I-p5+14. In some embodiments the amyloid reactive peptide comprises an amino acid sequence set forth in SEQ ID NO: 13. In some embodiments, the amyloid reactive peptide is conjugated to ¹²⁴I. In some embodiments, method for diagnosing a type of amyloid disease comprises administering an the amyloid reactive peptide comprising SEQ ID NO: 13 conjugated to ¹²⁴I.

[0112] In another embodiment, the methods for diagnosing a type of amyloid disease comprise administering an amyloid-reactive agent comprising a fluorescent label. In some embodiments, the agent fluorescently-labelled amyloid-reactive agent is thioflavin T (ThT). [0113] In some embodiments, the amyloid-reactive agent comprises an amyloidreactive peptide conjugated to a radiolabel. In some embodiments, the amyloid-reactive agent comprises a peptide conjugated to a bulking agent. In some embodiments, the amyloid-reactive peptide is conjugated to PEG. In some embodiments, the amyloid-reactive peptide is conjugated to an antibody.

[0114] In some embodiments, the amyloid-reactive agent specifically binds to amyloid deposits. In some embodiments, the amyloid-reactive agent is able to detect the presence, absence, or amount of amyloid in the subject. In some embodiments, the amyloidreactive agent or dye cross-reacts to amyloid deposits formed by a number of different proteins. In some embodiments, the amyloid-reactive agent binds to amyloid deposits formed by a variety of proteins and/or peptides. In some embodiments, the amyloid-reactive agent binds to amyloid deposits formed by amyloid light chain (AL). In some embodiments, the amyloid-reactive agent binds to amyloid formed by transthyretin (TTR) fibrils. In some embodiments, the amyloidreactive agent binds to amyloid formed by serum amyloid protein A (sAA). In some embodiments, the amyloid-reactive agent binds to amyloidogenic forms of immunoglobulin light chain (AL), immunoglobulin heavy chain (AH), P2-microglobulin (AP2M), transthyretin variants (ATTRv), wild type transthyretin (ATTRwt), apolipoprotein Al (AApoAI), apolipoprotein All variants (AApoAII), apolipoprotein AIII variants (AApoAIII), gelsolin (AGel), lysozyme (ALys), leukocyte chemotactic factor (ALECT2), fibrinogen a variants (AEib), cystatin variants (ACys), calcitonin ((ACal), lactadherin (AMed), islet amyloid polypeptide (AIAPP), prolactin (APro), insulin (Alns), prior protein (APrP); a-synuclein (AaSyn), tau (ATau), atrial natriuretic factor (AANL), or IAAP, ALK4, AL I other amyloidogenic peptides.

[0115] In some embodiments, the amyloid-reactive agent binds to heperan sulfate glycosaminoglycans (GAGs). In some embodiments GAGs are associated with amyloid deposits. Binding of GAGs to amyloid fibrils occurs mainly through electrostatic interactions involving the negative polyelectrolyte charges and positively charged side chains residues of aggregating protein. Similarly to catalyst for reactions, GAGs favor aggregation, nucleation and amyloid fibril formation functioning as a structural templates for the self-assembly of highly cytotoxic oligomeric precursors, rich in P-sheets, into amyloid fibrils. Moreover, the GAGs amyloid promoting activity can be facilitated through specific interactions via consensus binding sites between amyloid polypeptide and GAG molecules. [0116] In some embodiments, the method comprises administering an amyloidreactive agent to an individual. In some embodiments, the amyloid-reactive agent is administered in a pharmaceutical composition. In some embodiments, the composition comprises an aqueous buffer. The compositions may also include a solubilizing agent and a local anesthetic such as lignocaine to ease pain at the site of the injection. The ingredients are supplied either separately or mixed together in unit dosage form, for example, as a dry lyophilized powder or water free concentrate in a hermetically sealed container such as an ampule indicating the quantity of active agent. Where the composition is to be administered by infusion, it can be dispensed with an infusion bottle containing sterile pharmaceutical grade water or saline. Where the composition is administered by injection, an ampule of sterile water for injection or saline can be provided so that the ingredients may be mixed prior to administration.

[0117] The compositions may further comprise a carrier. The present invention also provides pharmaceutical compositions comprising one or more peptides and/or fusion peptides of the present invention. Such pharmaceutical compositions comprise an effective amount of the peptide or fusion peptide for binding to and detection of amyloids and a pharmaceutically acceptable carrier.

[0118] Pharmaceutically acceptable carriers include solid or liquid carriers or components which may be added to enhance or stabilize the composition, or to facilitate preparation of the composition include, without limitation, syrup, water, isotonic saline solution, 5% dextrose in water or buffered sodium or ammonium acetate solution, oils, glycerin, alcohols, among others. Examples of oils include those of petroleum, animal, vegetable or synthetic origin, such as peanut oil, soybean oil, mineral oil, and sesame oil. The carrier may also include a sustained release material such as glyceryl monostearate or glyceryl distearate, alone or with a wax. Other suitable pharmaceutical carriers include but are not limited to include starch, glucose, lactose, sucrose, gelatin, malt, rice, flour, chalk, silica gel, sodium stearate, glycerol monostearate, talc, sodium chloride, dried skim milk, propylene, glycol, water, ethanol, flavoring agents, preservatives, coloring agents diluents, granulating agents, lubricants, binders, and the like.

[0119] Water may be the preferred carrier when the pharmaceutical composition is administered intravenously. Saline solutions and aqueous dextrose and glycerol solutions can also be employed as liquid carriers, particularly for injectable solutions. The composition, if desired, can also contain minor amounts of wetting or emulsifying agents, or pH buffering agents. Such compositions can take the form of solutions, suspensions, emulsion, tablets, pills, capsules, powders, sustained-release formulations and the like. The compositions can be formulated as a suppository, with traditional binders and carriers such as triglycerides. Oral formulations can include standard carriers such as pharmaceutical grades of mannitol, lactose, starch, magnesium stearate, sodium saccharine, cellulose, magnesium carbonate, etc. Examples of other suitable pharmaceutical carriers are described in “Remington's Pharmaceutical Sciences” by E. W. Martin.

[0120] Methods for imaging amyloids include but are not limited to magnetic resonance imaging (MRI), computed axial tomography (CAT) scanning, positron emission tomography (PET), ultrasonic imaging, x-rays, radionuclide imaging, single photon emission computed tomography (SPECT), and multiphoton microscopy.

[0121] To increase the sensitivity of scans, various contrast media may be used. The contrast media for scans may include all molecules that attenuate x-rays. For positron emission tomography and radionuclide imaging, radioisotopes may be used. All positron emitting isotopes are useful for positron emission tomography radionuclide imaging, and all y-photon emitting isotopes are useful for radionuclide imaging.

[0122] Contrast agents for ultrasonic imaging include positive agents and negative agents. Positive agents reflect the ultrasonic energy and thus they produce a positive (light) image. Correspondingly, negative agents enhance transmissibility or sonolucency and thus produce a negative (dark) image. A variety of substances — gases, liquids, solids, and combinations of these — has been investigated as potential contrast-enhancing agents. Examples of solid particle contrast agents disclosed in U.S. Pat. No. 5,558,854 include but not limited to IDE particles and SHU454. European Patent Application 0231091 discloses emulsions of oil in water containing highly fluorinated organic compounds for providing enhanced contrast in an ultrasound image. Emulsions containing perfluorooctyl bromide (PFOB) have also been examined as ultrasound imaging agents. U.S. Pat. No. 4,900,540 describes the use of phospholipid-based liposomes containing a gas or gas precursor as a contrast-enhancing agent.

[0123] Several classes of compounds have potential as MRI contrast agents. These classes include supraparamagnetic iron oxide particles, nitroxides, and paramagnetic metal chelates (Mann et al., 1995). A strong paramagnetic metal is preferred. Normally, paramagnetic 1 lanthanides and transition metal ions are toxic in vivo. Thus, it is necessary to incorporate these compounds into chelates with organic ligands. The peptides and fusion peptides of the present invention may be used to enhance the targeting of such chelated metals to amyloids, which allows for the reduction in the total dose of imaging composition otherwise required.

[0124] Imaging agents may be attached to peptides and fusion peptides using known methods. Certain attachment methods involve the use of a metal chelate complex employing, for example, an organic chelating agent such a DTPA. Acceptable chelates are known in the field. They include but are not limited to 1,4,7, 10-tetraazacyclododecane-N,N',N",N'"-tetraacetic acid (DOTA); l,4,7,10-tetraazacyclododecane-N,N',N"-triacetic acid (DO3A); 1,4,7- tris(carboxymethyl)-10-(2-hydroxypropyl)-l,4,7,10-tetraazacyclododecane (HP-DO3A); diethylenetriaminepentaacetic acid (DTPA); and many others.

[0125] Several classes of compounds have potential as MRI contrast agents. These classes include supraparamagnetic iron oxide particles, nitroxides, and paramagnetic metal chelates (Mann et al., 1995). A strong paramagnetic metal is preferred. Normally, paramagnetic lanthanides and transition metal ions are toxic in vivo. Thus, it is necessary to incorporate these compounds into chelates with organic ligands. The peptides and fusion peptides of the present invention may be used to enhance the targeting of such chelated metals to amyloids, which allows for the reduction in the total dose of imaging composition otherwise required.

[0126] Paramagnetic metals of a wide range are suitable for chelation. Suitable metals include those having atomic numbers of 22-29 (inclusive), 42, 44 and 58-70 (inclusive), and having oxidation states of 2 or 3. Examples of such metals include but are not limited to chromium (III), manganese (II), iron (II), cobalt (II), nickel (II), copper (II), praseodymium (III), neodymium (III), samarium (III), gadolinium (III), terbium (III), dysprosium (III), holmium (III), erbium (III), ytterbium (III), and vanadium (II). Ions useful in other contexts, such as X-ray imaging, include but are not limited to lanthanum (III), gold (III), lead (II), and especially bismuth (III).

[0127] Among the radioisotopes that can be used to label peptides and fusion peptides of the present invention that are suitable for localization studies are gamma-emitters, positron-emitters, X-ray-emitters and fluorescence-emitters. Appropriate radioisotopes for labeling peptides and fusion proteins include astatine²¹¹, bromine⁷⁶, ¹⁴carbon, ⁿcarbon, ⁵¹chromium, ³⁶chlorine, ⁵⁷ cobalt, ⁵⁸cobalt, copper⁶⁷, copper⁶⁴, ¹⁵²europium, fluorine¹⁸, gallium⁶⁷, Gallium⁶⁸, ³hydrogen, iodine¹²³, iodine¹²⁴, iodine¹²⁵, iodine¹²⁶, iodine¹³¹, indium¹¹¹, indium¹¹³"¹, ⁵⁹iron, ¹⁷⁷lutetium, mercury¹⁰⁷, mercury²⁰³, ³²phosphorus, rhenium¹⁸⁶, rhenium¹⁸⁸, ruthenium⁹⁵, ruthenium⁹⁷, ruthenium¹⁰³, ruthenium¹⁰⁵, rhenium⁹⁹"¹, rhenium¹⁰⁵, rhenium¹⁰¹, ⁷⁵ selenium, ³⁵sulphur, technitium⁹⁹¹”, telluriuml21m, tellurium¹²²"¹, tellurium¹²⁵¹”, thulium¹⁶⁵, thulium¹⁶⁷, thulium¹⁶⁸, and yttrium⁹⁰. The halogens may be used more or less interchangeably as labels. The gamma-emitters, iodine¹²³ and technetium⁹⁹¹”, may also be used because such radiometals are detectable with a gamma camera and have favorable half-lives for imaging in vivo. The positronemitters 18-fluorine or ¹²⁴iodine which are suitable for PET imaging and have suitable half-lives for peptide imaging may also be used. Peptides and fusion peptides of the present invention may be labeled with indium¹¹¹ or technetium⁹⁹¹” via a conjugated metal chelator, such as DTP A (diethlenetriaminepentaacetic acid) or non-covalently and directly to the flanking peptide that contains a Cys residue or triglycine motif.

[0128] Radioactively labeled peptides or fusion peptides may be produced according to well-known methods in the art. For instance, they can be iodinated by contact with sodium or potassium iodide and a chemical oxidizing agent such as sodium hypochlorite, or an enzymatic oxidizing agent, such as lactoperoxidase. Peptides or fusion peptides according to the invention may be labeled with technetium⁹⁹¹” by ligand exchange process, for example, by reducing pertechnate with stannous solution, chelating the reduced technetium onto a Sephadex column and applying the peptide to this column or by direct labeling techniques, e.g., by incubating pertechnate, a reducing agent, such as SnCh, a buffer solution such as sodium-potassium phthalate solution, and the peptide. Intermediary functional groups that are often used to bind radioisotopes that exist as metallic ions to peptides are diethylenetriaminepenta- acetic acid (DTPA) and ethylene diaminetetra- acetic acid (EDTA), as mentioned earlier.

[0129] Other useful labels include fluorescent labels, chromogenic labels, and biotin labels. Fluorescent labels, include but are not limited to rhodamine, fluorescein isothiocyanate, fluorescein sodium, renographin, and Texas Red sulfonyl chloride. In certain embodiments, the peptides and fusion peptides of the present invention may be linked to a secondary binding ligand or to an enzyme (an enzyme tag) that will generate a colored product upon contact with a chromogenic substrate. Examples of suitable enzymes include urease, alkaline phosphatase, (horseradish) hydrogen peroxidase and glucose oxidase. Secondary binding ligands include biotin and avidin or streptavidin compounds. The use of such labels is well known to those of skill in the art in light and is described, for example, in U.S. Pat. Nos. 3,817,837; 3,850,752; 3,939,350; 3,996,345; 4,277,437; 4,275,149 and 4,366,241; each incorporated herein by reference.

[0130] The present invention provides a method for detecting amyloids in a subject. The method comprises administering a pharmaceutical composition comprising an effective amount of one or more peptides or fusion peptides of the present invention to a subject and detecting the peptides or fusion peptides bound to the amyloids. The peptides may be labeled with an imaging agent, such as a radioisotope. The peptide has specific binding affinity for the deposits and the binding is detectable. The binding of the peptides or fusion peptides to the amyloids may be detected by MRI, CAT scan, PET imaging, ultrasound imaging, SPECT imaging, X-ray imaging, fluorescence imaging, or radionuclide imaging.

[0131] In some instances, the methods for diagnosing a type of amyloid disease comprise administering to an individual a detectable amount of an amyloid-reactive reagent or dye. The detectable amount to be administered may be based on the type of detection to be performed. For example, in some embodiments, a detectable amount of an amyloid-reactive reagent or dye may be an amount sufficient to be detectable by imaging when administered to a subject. The detectable amount of the amyloid-reactive agent to be administered to an individual may vary depending upon such factors as the age, sex and weight of the individual, the specific response of the individual, the dosimetry, the formulation, and instrument-related factors. Optimization of such factors is well within the level of skill in the art. The detectable amount of the amyloid-reactive agent may also vary with the mode of administration of the amyloidreactive agent or detection dye.

[0132] In some instances, the amyloid-reactive agent is administered parenterally, paracancerally, transmucosally, tansdermally, intramuscularly, intravenously, intradermally, subcutaneously, intraperitonealy, intraventricularly, or intracranially. In some instances, the amyloid-reactive agent is administered intravenously. In other instances, the amyloid-reactive agent is administered intraperitonealy.

[0133] One of ordinary skill in the art will further appreciate that an effective amount of the amyloid-reactive agent can be administered in a single dose, or can be achieved by administering multiple doses. In some instances, the administration of the amyloid-reactive agent may further comprise administering a flushing solution. For example, a flushing solution, e.g. saline, may be administered after immediately after administration of the amyloid-reactive agent or detection dye, or after a set period of time after administration of the amyloid-reactive agent or detection dye. In other instances, the amyloid-reactive agent may be metabolized and excreted a certain period of time after administration.

C. Detection of amyloid in organs and tissues

[0134] In some embodiments, the methods of diagnosing an amyloid-related disease comprise detecting amyloids with an amyloid-reactive agent or detection dye. Examples of amyloids that can be detected as part of the present methods include, but are not limited to, amyloidogenic forms of immunoglobulin heavy chain (AH), p2-microglobulin (Ap2M), transthyretin variants (ATTR), amyloid beta (AP), apolipoprotein Al (AApoAI), apolipoprotein All (AApoAII), gelsolin (AGel), lysozyme (ALys), leukocyte chemotactic factor (ALect2), fibrinogen a variants (AFib), cystatin variants (ACys), calcitonin (ACal), lactadherin (AMed), islet amyloid polypeptide (AIAPP), prolactin (APro), insulin (Alns), prior protein (APrP); a- synuclein (AaSyn), tau (ATau), atrial natriuretic factor (AANF), or IAAP, and other amyloidogenic peptides. In some embodiments of the present disclosure, the method for diagnosing a type of amyloid disease comprises detecting ATTR, AL and/or ALECT2 amyloids. In other embodiments, the method for diagnosing a type of amyloid disease comprises distinguishing between ATTR, AL and ALECT2 amyloids.

[0135] In some embodiments, the methods can be for diagnosing an amyloid-related disease. In some embodiments, the amyloid-related disease is AL, AH, Ap2M, ATTRv, ATTRwt, AA, AApoAI, AApoAII, AGel, ALys, ALECT2, AFib, ACys, ACal, AMed, AIAPP, APro, Alns, APrP, or Ap amyloidosis. In some embodiments, the amyloid-related disease is systemic amyloidosis. In some embodiments, the amyloid-related disease is cardiac amyloidosis. In some embodiments, the amyloid-related disease is cardiac AL amyloidosis. In some embodiments, the amyloid-related disease is cardiac ATTR amyloidosis.

[0136] In some embodiments, the methods for diagnosing an amyloid-related disease comprise administering an amyloid-reactive peptide conjugated to a detectable label to an individual, and measuring the amount of the detectable label at a tissue or organ in the individual, wherein the amount of signal from the amyloid-reactive peptide above a threshold value indicates that the individual has the amyloid disease. [0137] In some embodiments, the method comprise administering a dose of about 0.1 mCi to about 25 mCi of the amyloid reactive peptide conjugated to a detectable label to an individual. In some embodiments, the methods comprise administering a dose of about 0.3 mCi, 1 mCi, or about 2 mCi of the amyloid reactive peptide conjugated to a detectable label to an individual. In some embodiments, the methods comprise administering a dose of 1 mCi (±10%) of the amyloid reactive peptide conjugated to a detectable label to an individual. In some embodiments, the methods comprise administering a dose of between about 0.9 mCi and about 1.1 mCi of the amyloid reactive peptide conjugated to a detectable label to an individual. In some embodiments, the methods comprise administering a dose of 1 mCi (±10%) and not more than 2 mCi of the amyloid reactive peptide conjugated to a detectable label to an individual In some embodiments, the amyloid reactive peptide conjugated to a detectable label is ¹²⁴I-labeled amyloid-reactive peptide to the individual.

[0138] In some embodiments, the method comprise administering a dose of about 0.1 mCi to about 25 mCi of ¹²⁴I-labeled amyloid-reactive peptide to an individual. In some embodiments, the methods comprise administering a dose of about 0.3 mCi, 1 mCi, or about 2 mCi of ¹²⁴I-labeled amyloid-reactive peptide to an individual. In some embodiments, the methods comprise administering a dose of 1 mCi (±10%) of ¹²⁴I-labeled amyloid-reactive peptide to an individual. In some embodiments, the methods comprise administering a dose of between about 0.9 mCi and about 1.1 mCi of ¹²⁴I-labeled amyloid-reactive peptide to an individual. In some embodiments, the methods comprise administering a dose of 1 mCi (±10%) and not more than 2 mCi of ¹²⁴I-labeled amyloid-reactive peptide an individual

[0139] In some embodiments, the methods comprise administering about 0.3 mg, about 1 mg, about 1.5 mg, about 2 mg of an amyloid-reactive peptide to an individual. In some embodiments, the methods comprise administering between about 0.3 mg and about 2 mg, about 1 mg and about 2 mg, or about 1.5 mg and about 2 mg of an amyloid-reactive peptide to an individual. In some embodiments, the methods comprise administering between about 0.3 mg and about 1 mg, about 0.3 mg and about 1.5 mg of an amyloid-reactive peptide to an individual.

[0140] In some embodiments, the step of detecting the amyloid-reactive agent in one or more organs as in the present methods comprises determining an organ uptake value for each organ. Organ uptake may be determined by methods known to those skilled in the art. For example, the organ uptake value may indicate the relative or absolute levels of the amyloid- reactive agent detected in each organ in an individual. In some embodiments, the organ uptake value ratio is a relative uptake value. In some embodiments, the organ uptake value is a standard uptake value (SUV) for each organ. In some embodiments, As would be appreciated by those skilled in the art, the standard uptake value may be determined by measuring the amount of amyloid-reactive agent detected in a reactive organ, e.g. heart, relative to the amount of amyloidreactive agent detected in a non-reactive tissue or sample, e.g. blood. The amount of amyloidreactive agent in an organ may be determined, for example, by quantifying the detectable signal from the amyloid-reactive agent in an organ, e.g. by computing pixel values in an image. In some embodiments, the standard uptake value is determined as the ratio of the amount of amyloid-reactive agent detected in an organ, and the amount of amyloid-reactive agent detected in blood. In some embodiments, the organ uptake value is indicative of the organ distribution pattern of the amyloid-reactive agent or detection dye. In some embodiments, the method comprises determining an organ- specific SUV for the individual. In some embodiments, the organ- specific SUV for the individual is selected from the group consisting of SUV mean, SUV max, and SUV peak.

[0141] In some embodiments, the organ uptake is based upon an organ- specific standard uptake value ratio (SUVR). In some embodiments, a SUVR is calculated using a blood pool as a reference tissue. In some embodiments, the SUVR is calculated for each organ by dividing the amount of amyloid detection agent or dye in the organ by the blood pool ratio. In some embodiments, the blood pool is a vein or artery. In some embodiments, the blood pool is the lumen of the thoracic aorta. In some embodiments, the organ- specific SUVR for the individual is selected from the group consisting of SUVR mean, SUVR max, and SUVR peak. In some embodiments, the organ- specific SUVR for the individual is an SUVR mean. In some embodiments, an organ- specific SUVR is utilized to control for differences in radiotracer clearance rates.

[0142] In some embodiments, the threshold is an SUVR mean threshold value. In some embodiments, the SUVR mean threshold value is a SUVR mean threshold value based on an organ or tissue. The SUVR mean threshold may be chosen according to the organ or tissue that the amyloid-reactive peptide conjugated to a detectable label is detected in. In some embodiments, the organ or tissue is a liver, spleen, kidney, pancreas, heart, or adrenal glands. In some embodiments, detecting the amyloid reactive peptide conjugated to a detectable label above the SUVR mean threshold level allows for diagnosis of an amyloid-related disorder at an early stage.

[0143] In some embodiments, the threshold an SUVR mean threshold value. In some embodiments, the SUVR mean threshold value is 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, or 1.6 if the organ or tissue is a liver. In some embodiments, the SUVR mean threshold value is 1.31 if the organ or tissue is a liver. In some embodiments, if the SUVR mean in the liver of the individual is above a threshold of 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, or 1.6, the individual is likely to have systemic amyloidosis or a type of systemic amyloidosis. In some embodiments, if the SUVR in the liver of the individual is above a threshold of 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, or 1.6, the individual is diagnosed as having systemic amyloidosis or a type of systemic amyloidosis.

[0144] In some embodiments, the threshold is an SUVR mean threshold value. In some embodiments, the SUVR mean threshold value is 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, or 1.5 if the organ or tissue is a spleen. In some embodiments, the SUVR mean threshold value is 1.21 if the organ or tissue is a spleen. In some embodiments, if the SUVR mean in the spleen of the individual is above a threshold of 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, or 1.5 the individual is likely to have systemic amyloidosis or a type of systemic amyloidosis. In some embodiments, if the SUVR mean in the spleen of the individual is above a threshold of 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, or 1.5 the individual is diagnosed as having systemic amyloidosis or a type of systemic amyloidosis.

[0145] In some embodiments, the threshold is an SUVR mean threshold value. In some embodiments, the SUVR mean threshold value is 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, or 2.3 if the organ or tissue is a kidney. In some embodiments, the SUVR mean threshold value is 1.88 (or is between 1.69 and 2.07) if the organ or tissue is a kidney. In some embodiments, if the SUVR mean in the kidney of the individual is above a threshold of 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, or 2.3 the individual is likely to have systemic amyloidosis or a type of systemic amyloidosis. In some embodiments, if the SUVR mean in the kidney of the individual is above a threshold of 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, or 2.3 the individual is diagnosed as having systemic amyloidosis or a type of systemic amyloidosis.

[0146] In some embodiments, the threshold is an SUVR mean threshold value. In some embodiments, the SUVR mean threshold value is 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, or 1.7 if the organ or tissue is a pancreas. In some embodiments, the SUVR mean threshold value is 1.40 if the organ or tissue is a pancreas. In some embodiments, if the SUVR mean in the pancreas of the individual is above a threshold of 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, or 1.7 the individual is likely to have systemic amyloidosis or a type of systemic amyloidosis. In some embodiments, if the SUVR mean in the pancreas of the individual is above a threshold of 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, or 1.7 the individual is diagnosed as having systemic amyloidosis or a type of systemic amyloidosis.

[0147] In some embodiments, the threshold is an SUVR mean threshold value. In some embodiments, the SUVR mean threshold value is 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7,

1.8, 1.9, 2.0, or 2.1 if the organ or tissue is a heart. In some embodiments, the SUVR mean threshold value is 1.19 if the organ or tissue is a heart. In some embodiments, if the SUVR mean in the heart of the individual is above a threshold of 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8,

1.9, 2.0, or 2.1 the individual is likely to have systemic amyloidosis or a type of systemic amyloidosis. In some embodiments, if the SUVR mean in the heart of the individual is above a threshold of 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, or 2.1 the individual is diagnosed as having systemic amyloidosis or a type of systemic amyloidosis.

[0148] In some embodiments, the threshold is an SUVR mean threshold value. In some embodiments, the SUVR mean threshold value is 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, or 1.4 if the organ or tissue is an adrenal gland. In some embodiments, the SUVR mean threshold value is 1.135 if the organ or tissue is an adrenal gland. In some embodiments, if the SUVR mean in the adrenal gland of the individual is above a threshold of 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, or 1.4 the individual is likely to have systemic amyloidosis or a type of systemic amyloidosis. In some embodiments, if the SUVR mean in the adrenal gland of the individual is above a threshold of 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, or 1.4 the individual is diagnosed as having systemic amyloidosis or a type of systemic amyloidosis.

[0149] In some embodiments, the threshold is an SUVR max threshold value. In some embodiments, the SUVR max threshold value is a SUVR max threshold value based on an organ or tissue. The SUVR max threshold may be chosen according to the organ or tissue that the amyloid-reactive peptide conjugated to a detectable label is detected in. In some embodiments, the organ or tissue is a liver, spleen, kidney, pancreas, heart, or adrenal glands. In some embodiments, detecting the amyloid reactive peptide conjugated to a detectable label above the SUVR max threshold level allows for diagnosis of an amyloid-related disorder at an early stage. [0150] In some embodiments, the threshold is an SUVR max threshold value. In some embodiments, the SUVR max threshold value is 10.6, 10.7, 10.8, 10.9, 11, 11.1, 11.2, 11.3, 11.4, 11.5, 11.6, 11.7, 11.8, 11.9, 12, 12.1, 12.2, 12.3, 12.4, 12.5, 12.6, 12.7, 12.8, 12.9, 13, 13.1, 13.2, 13.3, 13.4, 13.5, 13.6, 13.7, 13.8, 13.9, 14, 14.1, 14.2, 14.3, 14.4, 14.5, 14.6, 14.7, 14.8, 14.9, 15, 15.1, 15.2, 15.3, 15.4, 15.5, 15.6, 15.7, 15.8, 15.9, or 16 if the organ or tissue is a liver. In some embodiments, the SUVR max threshold value is 13.26 if the organ or tissue is a liver.

[0151] In some embodiments, the threshold is an SUVR max threshold value. In some embodiments, the SUVR max threshold value is 3.8, 3.9, 4, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7,

4.8, 4.9, 5, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, or 5.9 if the organ or tissue is a spleen. In some embodiments, the SUVR max threshold value is 4.86 if the organ or tissue is a spleen.

[0152] In some embodiments, the threshold is an SUVR max threshold value. In some embodiments, the SUVR max threshold value is 7.7, 7.8, 7.9, 8, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6,

8.7, 8.8, 8.9, 9, 9.1, 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, 9.9, 10, 10.1, 10.2, 10.3, 10.4, 10.5, 10.6,

10.7, 10.8, 10.9, 11, 11.1, 11.2, 11.3, 11.4, 11.5, 11.6, or 11.7 if the organ or tissue is a kidney. In some embodiments, the SUVR max threshold value is 9.68 if the organ or tissue is a kidney.

[0153] In some embodiments, the threshold is an SUVR max threshold value. In some embodiments, the SUVR max threshold value is 7.5, 7.6, 7.7, 7.8, 7.9, 8, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 9, 9.1, 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, 9.9, 10, 10.1, 10.2, 10.3, 10.4, 10.5, 10.6, 10.7, 10.8, 10.9, 11, 11.1, 11.2, 11.3, or 11.4 if the organ or tissue is a pancreas. In some embodiments, the SUVR max threshold value is 9.48 if the organ or tissue is a pancreas.

[0154] In some embodiments, the threshold is an SUVR max threshold value. In some embodiments, the SUVR max threshold value is 4.9, 5, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8,

5.9, 6, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9, 7, 7.1, 7.2, 7.3, 7.4, or 7.5 if the organ or tissue is a heart. In some embodiments, the SUVR max threshold value is 6.2 if the organ or tissue is a heart.

[0155] In some embodiments, the threshold is an SUVR max threshold value. In some embodiments, the SUVR max threshold value is 1, 1.1, 1.2, 1.3, 1.4, 1.5, or 1.6 if the organ or tissue is an adrenal gland. In some embodiments, the SUVR max threshold value is 1.31 if the organ or tissue is an adrenal gland.

[0156] In some embodiments, and the steps of measuring the organ uptake value or organ uptake value ratio of the amyloid-reactive agent in one or more organs comprises analyzing imaging data. The imaging data may be generated by any procedure known in the art that may allow the imaging of the amyloid-reactive reagent or dye. For example, the amyloidreactive agent may be detected by positron emission tomography (PET), computed tomography (CT), magnetic resonance imaging (MRI), or single-photon emission computed tomography (SPECT). In certain embodiments, the amyloid-reactive agent may be detected by combined imaging methods such as PET/CT (PET with concurrent computed tomography imaging) or PET/MRI (PET with concurrent magnetic resonance imaging). The imaging procedure may result in one or more images of the region of observation of the individual. In certain embodiments, the imaging results in more than one image, these multiple images may be combined, overlaid, added, subtracted, color coded or otherwise fused and mathematically manipulated by any method known in the art. The image produced may be a digital or analog image that may be displayed as a “hard” image on, for example, printer paper, photographic paper or film, or as an image on a screen, such as for example, a video or LCD screen.

[0157] In some embodiments, PET images are analyzed using a region of interest (ROI) method. In some embodiments, the images are planar images. In some embodiments, the images are coronal, axial, or sagittal images.

[0158] In some embodiments, the threshold value for diagnosing a particular type of amyloid disease is selected based upon a desired sensitivity. In some embodiments, the cutoff is selected to provide a sensitivity of at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90% or at least 95%. In some embodiments, the sensitivity for detecting cardiac amyloid using the amyloid-reactive peptide conjugated to a detectable label is between about 80% and about 100%. In some embodiments, the sensitivity for detecting cardiac amyloid using the amyloid-reactive peptide conjugated to a detectable label is about 80%, about 85%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or about 100%. In some embodiments, the sensitivity for detecting cardiac amyloid using the amyloid-reactive peptide conjugated to a detectable label is about 96%.

[0159] In some embodiments, the sensitivity for detecting cardiac amyloid in patients with AL amyloidosis is between about 80% and about 100%. In some embodiments, the sensitivity for detecting cardiac amyloid in patients with AL amyloidosis is about 80%, about 85%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or about 100%. In some embodiments, the sensitivity for detecting cardiac amyloid in patients with AL amyloidosis is about 93%.

[0160] In some embodiments, the sensitivity for detecting cardiac amyloid in patients with ATTR amyloidosis is between about 80% and about 100%. In some embodiments, the sensitivity for detecting cardiac amyloid in patients with ATTR amyloidosis is about 80%, about 85%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or about 100%. In some embodiments, the sensitivity for detecting cardiac amyloid in patients with ATTR amyloidosis is about 100%.

[0161] In some embodiments, the threshold value is selected based upon a desired specificity (i.e. the ability to exclude individuals who do not have an amyloid-related disease). In some embodiments, the cutoff is selected to provide a specificity of at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90% or at least 95%.

[0162] In some embodiments, the threshold value is selected to obtain the optimal relationship between sensitivity and specificity based on organ- specific SUV or SUVR values. In some embodiments, the threshold value is selected that provides the highest Youden’s index. In some embodiments, the Youden’s index is determined by the following formula: sensitivity + specificity - 1. In some embodiments, if several SUV or SUVR provide the same Youden’s index, the SUV or SUVR that results in the highest specificity is selected.

[0163] In some embodiments, the heart SUVRmean threshold value for AL amyloidosis is between about 0.6 and about 4. In some embodiments, the heart SUVRmean threshold for AL amyloidosis is about 1.0, about 1.1, about 1.2, about 1.4, about 1.6, about 1.8, about 2.0, about 2.2, about 2.4, about 2.6, about 2.8, about 3, about 3.5, or about 4.0.

[0164] In some embodiments, the heart SUVRmean threshold value for ATTR amyloidosis is between about 0.6 and about 4. In some embodiments, the heart SUVRmean threshold for ATTR amyloidosis is about 1.0, about 1.1, about 1.2, about 1.4, about 1.6, about 1.8, about 2.0, about 2.2, about 2.4, about 2.6, about 2.8, about 3, about 3.5, or about 4.0.

[0165] In some embodiments, the sensitivity and specificity of the amyloid-reactive peptide conjugated to a detectable label are defined relative to clinically approved methods to diagnose an amyloid-related disease. In some embodiments, the clinically approved method is selected from the group consisting of a measure of the health related quality of life of the individual, the presence or amount of one or more biomarkers associated with the amyloid- related disease, a cardiac biopsy, and additional amyloid imaging of the individual. In some embodiments, the sensitivity and specificity of the amyloid-reactive peptide conjugated to a detectable label are defined relative a diagnosis derived from an individual’s medical record.

[0166] In some embodiments, the sensitivity of the amyloid-reactive peptide is the specificity of the amyloid-reactive peptide conjugated to a detectable label. In some embodiments, the sensitivity of the amyloid-reactive peptide conjugated to a detectable label is measured as the true positives divided by the true positives added to the false negatives. In some embodiments, the true positives is the number of individual correctly diagnosed with an amyloid-related disease by the amyloid-reactive peptide conjugated to a detectable label when the individual does have the amyloid-related disease. In some embodiments, the false negatives is the number of individuals that are incorrectly diagnosed as not having an amyloid-related disease by the amyloid-reactive peptide conjugated to a detectable label when the individual does have the amyloid-related disease. In some embodiments, the sensitivity can be defined as a confidence interval of the sensitivity value. In some embodiments, the sensitivity can be defined according to the 95% confidence interval of the sensitivity value. In some embodiments, the 95% confidence interval can be calculated using the Wilson - Brown method.

[0167] In some embodiments, the sensitivity of the amyloid-reactive peptide conjugated to a detectable label is the sensitivity of the detection of an amyloid-related disease after administering of the amyloid-reactive peptide and detection of the radiolabel through amyloid imaging. In some embodiments, the sensitivity of the amyloid-reactive peptide conjugated to a detectable label relates to the dose of the amyloid-reactive peptide conjugated to a detectable label administered to an individual.

[0168] In some embodiments, the specificity of the amyloid-reactive peptide is the specificity of the amyloid-reactive peptide conjugated to a detectable label. In some embodiments, the specificity of the amyloid-reactive peptide conjugated to a detectable label is measured as the true negatives divided by the true negatives plus the false positives. In some embodiments, the true negatives is the number of individuals that are correctly diagnosed as not having an amyloid-related disease by the amyloid-reactive peptide conjugated to a detectable label when the individual does not have the amyloid-related disease. In some embodiments, the false positives is the number of individuals diagnoses as having an amyloid-related disease by the amyloid-reactive peptide conjugated to a detectable label when the individual does not have an amyloid-related disease. In some embodiments, the specificity can be defined as a confidence interval of the sensitivity value. In some embodiments, the specificity can be defined according to the 95% confidence interval of the specificity value. In some embodiments, the 95% confidence interval can be calculated using the Wilson - Brown method.

[0169] In some embodiments, the specificity of the amyloid-reactive peptide conjugated to a detectable label is the specificity of the detection of an amyloid-related disease after administering of the amyloid-reactive peptide and detection of the radiolabel through amyloid imaging. In some embodiments, the specificity of the amyloid-reactive peptide conjugated to a detectable label relates to the dose of the amyloid-reactive peptide conjugated to a detectable label administered to an individual. In some embodiments, the step of detecting the amyloid-reactive agent is performed in more than one organ in an individual. In some embodiments, the detecting step further comprises measuring the organ distribution pattern of the amyloid-reactive agent or detection dye, wherein the organ distribution pattern of the amyloid-reactive agent indicates a type of amyloid disease. The type of amyloid disease may be a sporadic amyloidosis, or have a genetic component, e.g. hereditary amyloidosis. Some nonlimiting examples of amyloid diseases are AA amyloidosis, AL amyloidosis, AH amyloidosis, Ap amyloidosis, ATTR amyloidosis, ALect2 amyloidosis, and IAPP amyloidosis of type II diabetes, Alzheimer’s disease, Down's syndrome, hereditary cerebral hemorrhage with amyloidosis of the Dutch type, cerebral beta-amyloid angiopathy, spongiform encelohalopathy, thyroid tumors, Parkinson’s disease, dementia with Lewis bodies, a tauopathy, Huntington’s disease, senile systemic amyloidosis, familial hemodialysis, senile systemic aging, aging pituitary disorder, iatrogenic syndrome, spongiform encephalopathies, reactive chronic inflammation, thyroid tumors, myeloma or other forms of cancer. In some embodiments, the type of amyloid disease is a systemic amyloid disease. In some embodiments, the type of amyloid disease is AL amyloidosis, ATTR amyloidosis, or ALECT2 amyloidosis. In some embodiments the amyloid disease is cardiac amyloidosis. In some embodiments, the amyloid disease is cardiac AL amyloidosis. In some embodiments, the amyloid disease is cardiac ATTR amyloidosis.

[0170] In some embodiments, the methods for diagnosing an amyloid-related disease comprise measuring the organ distribution pattern of the amyloid-reactive agent in one or more organs. Without being bound by theory, it is thought that the anatomic distribution of amyloid in each of form of the disease may have a specific pattern. For example, the amyloid deposits in ATTR amyloidosis are prevalent in the heart and peripheral nerves, while AL amyloidosis, another common amyloidosis, exhibits a variable pattern of amyloid deposition, with amyloids observed in, for example, the heart, spleen, liver, kidneys, peripheral nerves, gastrointestinal tract, muscle, lung, and lymph nodes. In some embodiments, the methods for diagnosing the type of amyloid disease comprise measuring the organ distribution pattern of the amyloid-reactive agent in one or more of heart, spleen, liver, kidneys, peripheral nerves, the gastrointestinal tract, muscle, lungs, brain, and lymph nodes. In some embodiments, the one or more organs are abdominothoracic organs. In some embodiments, the one or more organs are heart, spleen, liver, or kidney.

[0171] In other instances, the methods for diagnosing an amyloid-related disease comprise administering an amyloid-reactive agent and calculating an organ-to-organ ratio for two or more organs. In some instances, the step of calculating an organ-to-organ ratio for two or more organs comprises calculating the ratio between the organ uptake value for a first organ and the organ uptake value for a second organ. In some instances, the organ-to-organ ration is selected from the group consisting of liver-to-heart, spleen-to-heart, spleen-to-liver, spleen-to- kidney, kidney-to-heart, and kidney-to-liver. In some instances, the organ-to-organ ratio is the heart-to-spleen ratio. In some instances, the organ-to-organ ratio is between 0 and 1, 1, or higher than 1. In some instances, the organ-to-organ is indicative of the type of amyloid disease in an individual.

[0172] In some embodiments, an organ uptake value or organ-to-organ ratio are indicative of the type of amyloid disease. In some embodiments, the organ uptake value or the organ-to-organ ratio are indicative of the type of amyloid disease only if they are above a cut-off or threshold value. For example, in some embodiments, if the organ-to-organ ration is 1.4 for a type of amyloid disease, then a diagnosis of that type of amyloid disease will be made if an organ-to-organ ratio of 1.4 or more is calculated for an individual. As another non-limiting example, if an organ uptake value cut-off is 1.4 for a type of amyloid disease, then a diagnosis of that type of amyloid disease is not appropriate if an organ-to-organ ratio below 1.4 is calculated for an individual. The particular cut-off or threshold value for diagnosing the type of amyloid disease may vary with the type of amyloid disease, disease progression, patient demographics, the amyloid-reactive agent administered, and the detection method used. In some embodiments, the organ uptake value or organ-to-organ cut-off or threshold value is calculated from data from organ distribution of an amyloid-reactive agent or detection dye. In some embodiments, the organ uptake value or organ-to-organ cut-off or threshold value is calculated from data from a population with a particular type of amyloid disease.

[0173] Preferably, the organ uptake values or the organ-to-organ uptake ratio cut-off or threshold values for diagnosing the type of amyloid disease is determined using a receiver operator characteristic curve. As is understood in the art, the receiver operating characteristic curve, or, ROC curve, is a plot of the performance of a particular feature for distinguishing two populations, patients with an amyloid disease, and controls, e.g., those without an amyloid disease. Data across the entire population (namely, the patients and controls) are sorted in ascending order based on the value of a single feature (e.g. organ uptake value). Then, for each value for that feature, the true positive and false positive rates for the data are determined. The true positive rate (sensitivity) is determined by counting the number of cases above the value for that feature under consideration and then dividing by the total number of patients. The false positive rate (specificity) is determined by counting the number of controls above the value for that feature under consideration and then dividing by the total number of controls.

[0174] ROC curves can be produced for a single feature as well as for other single outputs, for example, combinations of two or more features are mathematically added together (added, drawn, multiplied, etc.) to provide a single total value, which can be plotted in the ROC curve. Furthermore, any combination of multiple features by which the combination leads to a single output value can be plotted in the ROC curve. These combinations of features may include testing. The ROC curve is a plot of the true positive rate (sensitivity) of the test against the false positive rate (1 -specificity) of the test. The area under the ROC curve can be a figure of merit for a given sample population, with the test ranging from 1 to 0 for a complete test that gives a completely random response in classifying the test subjects. As with any diagnostic application, the area under the ROC curve is indicative of the predictive power of the model, and can be used to compare the predictive power of one model against another. Using the ROC curve a cut-off value can be selected for diagnosing an amyloid disease and/or amyloid type in an individual with high confidence.

[0175] In some embodiments, the method comprises obtaining organ distribution data for an amyloid-reactive agent or detection dye. In some embodiments, organ distribution data are images. The images produced using the imaging procedure embodied in the present invention may be analyzed by any method known in the art. For example, in some embodiments, imaging data derived from a PET or SPECT scan can be inputted into a processor that identifies individual pixels or groups of pixels whose brightness is greater than a predetermined threshold or an average background, and identified pixels may be characterized as indicating the presence of the amyloid-reactive reagent or dye. In another embodiment, the image data may be derived from images scanned and inputted into a processor. In such embodiments, a similar process that identifies bright spots on the image may be used to locate the amyloid-reactive reagent or dye in the image. In certain embodiments, the analysis of the image may further include determining the intensity, concentration, strength or combination thereof of the output brightness, which may be correlated to the amount of radiolabeled protein in the image, an area or region of the image, or a particular spot on the image. Without wishing to be bound by theory, an area or spot on an image having a greater intensity than other areas or spots may hold a higher concentration of radiolabeled protein targeted to, for example, an amyloid deposit, and thus may have a higher concentration of the radiolabeled-amyloid-reactive reagent or dye attached to the region where the amyloid-reactive reagent or dye localizes.

[0176] In some embodiments, the method for diagnosing a type of amyloid disease comprises analyzing images by the spatial location of regions of interest to which the administered amyloid-reactive agent or detectable dye are targeted. In other embodiments, analysis of the pharmacokinetics of the administered amyloid-reactive reagent or dye may provide information on the appropriate timing of injection of the amyloid-reactive reagent or dye. By identifying areas, regions, or spots on an image that correlate to the presence of a radiolabeled protein, the presence or absence of amyloids may be determined. For example, in some embodiments, identifying regions or spots where the amyloid-reactive agent concentrates indicates the presence of amyloids. In some embodiments, images that correlate to the presence of an amyloid-reactive agent are used to diagnose an amyloid disease in an individual.

[0177] In some embodiments, the method further comprises providing a diagnosis of a type of amyloid disease based upon the organ distribution pattern. In some embodiments, a particular organ distribution pattern is indicative of a particular type of amyloid disease. For example, in some embodiments, the heart to spleen, heart to liver, spleen to liver, spleen to kidney, kidney to heart, or kidney to liver ratio is used to diagnose ATTR. In some embodiments, the heart to spleen, heart to liver, spleen to liver, spleen to kidney, kidney to heart, or kidney to liver ratio is used to diagnose ALECT2. In some embodiments, the heart to spleen, heart to liver, spleen to liver, spleen to kidney, kidney to heart, or kidney to liver ratio is used to diagnose AL.

[0178] In some embodiments, different types of amyloid diseases have different relative organ to organ ratios. In some embodiments, one particular type of amyloid disease may have a higher liver to heart ratio than another. In some embodiments, the heart to spleen ratio for individuals diagnosed with AATR is higher than the heart to spleen ratio for individuals diagnosed with AL. In some embodiments, the heart to spleen ratio for individuals diagnosed with ATTR is higher than the heart to spleen ratio for individuals diagnosed with ALECT2.

[0179] In some embodiments, the level amyloid-reactive agent in the heart is highest in individuals with ATTR. In some embodiments, the level of amyloid-reactive agent in the liver is highest in individuals with AL. In some embodiments, the level of amyloid-reactive agent is highest in the spleen in individuals with ALECT2. In some embodiments, the level of amyloid reactive agent is highest in the kidney in individuals with ALECT2.

[0180] In some embodiments, the level of amyloid reactive agent is lowest in the heart in individuals with ALECT2. In some embodiments, the level of amyloid-reactive agent in the liver is lowest in individuals with ATTR. In some embodiments, the level of amyloidreactive agent in the spleen is lowest in individuals with ATTR. In some embodiments, the level of amyloid-reactive agent in the kidney is lowest in individuals with ATTR.

[0181] In some embodiments, the cutoff value for diagnosing a particular type of amyloid disease is selected based upon a certain p value. In some embodiments, the cutoff is selected to provide a p-value of less than 0.1, less than 0.05, less than 0.01, less than 0.005, or less than 0.001.

[0182] One of ordinary skill in the art will appreciate that each of the ratios discussed herein can easily converted to its inverse. For example, a heart to spleen ratio of 2: 1 (2) is the same as a spleen to heart ratio of 1:2 (0.5).

[0183] In some embodiments, the diagnosis is confirmed by a measure of the health related quality of life of the individual. In some embodiments, the diagnosis is confirmed by the presence or amount of one or more biomarkers associated with the amyloid-related disease. In some embodiments, the diagnosis is confirmed by a cardiac biopsy. In some embodiments, the diagnosis is confirmed by additional amyloid imaging of the individual. [0184] In some embodiments, the method further comprises administering potassium iodide to the individual. The potassium iodide may protect the individual’s thyroid gland. In some embodiments, the potassium iodide is administered orally. In some embodiments, 130 mg of potassium iodide is administered for 7 days starting one day before administration of the amyloid-reactive agent. In some embodiments, 130 mg of potassium iodide is administered for 3 days starting the day of the administration of the amyloid-reactive agent, for example about 30 minutes before the administration of the amyloid-reactive agent.

D. Patient population

[0185] In some embodiments, the methods of diagnosing a type of amyloid disease are particularly useful in individuals at risk of developing an amyloid-related disease. In some embodiments, the individuals at risk of developing an amyloid-related disease have a family history of amyloid-related disease. In some embodiments, the individuals are at risk of developing a hereditary form of an amyloid-related disease. In some embodiments, the hereditary form of an amyloid-related disease comprises hereditary transthyretin amyloidosis (hATTR).

[0186] In some embodiments, the individual is determined to be at risk for an amyloid-related disease based upon the presence of a genetic mutation. In some embodiments, the genetic mutation is an ATTR genetic mutation. In some embodiments, the genetic mutation is within the TTR gene. In some embodiments, the genetic mutation comprises a point mutation resulting in an amino acid substitution e.g., of valine by methionine at position 30 (Val30Met).

[0187] In some embodiments, the individual is determined to be at risk for an amyloid-related disease based upon having multiple myeloma. In some embodiments, the individual at risk for developing an amyloid-related disease has smoldering multiple myeloma. In some embodiments, the individual is at risk for developing Immunoglobulin light chain amyloidosis (AL) based upon having multiple myeloma.

[0188] In some embodiments, the individual is determined to be at risk for an amyloid-related disease based upon having monoclonal gammopathy of undetermined significance (MGUS).

[0189] In some embodiments, the individual is determined to be at risk for an amyloid-related disease based upon having amyloid positive laminectomy tissue. In some embodiments, the individual is determined to be at risk for an amyloid-related disease based upon having amyloid positive carpal tunnel release tissue. In some embodiments, the individual is determined to be at risk for an amyloid-related disease based upon being elderly. In some embodiments, the individual is at least about 60, 65, 70, 75, 80, 85, or 90 years old. In some embodiments, the individual is at least 80 years old.

[0190] In some embodiments, the individual at risk of developing an amyloid-related disease displays symptoms of an amyloid-related disease. In some embodiments, the symptom of an amyloid-related disease is selected from the group consisting of swollen ankles and legs, severe fatigue, shortness of breath, significant weight loss, difficulty in swallowing, tingling, numbness or pain in the hands, wrist or feet, enlarged tongue, irregular heartbeat, diarrhea, and easy bruising, thickening, or purplish patches on the skin.

[0191] Alternatively, in some embodiments, the individual at risk of developing an amyloid-related disease does not display symptoms of an amyloid-related disease.

[0192] In some embodiments, the individual is suspected of having an amyloid- related disease. In some embodiments, an individual is suspected of having an amyloid-related disease, but has not been diagnosed with the amyloid-related disease. In some embodiments, the individual has not undergone a diagnostic evaluation for the amyloid related disease. In some embodiments, the individual has undergone diagnostic evaluation for the amyloid-related disease and the diagnostic evaluation did not detect the amyloid-related disease. In some embodiments, the individual has not been diagnosed according to the Mayo Clinic System. In some embodiments, the individual suspected of having an amyloid-related disease displays symptoms of an amyloid-related disease. Alternatively, in some embodiments, the individual is at risk of developing an amyloid-related disease and does not display symptoms of an amyloid-related disease. In some embodiments, individual suspected of having an amyloid-related disease has a genetic predisposition to an amyloid-related disease. In some embodiments, individual suspected of having an amyloid-related disease has a family history of any amyloid-related disease. In some embodiments, individual suspected of having an amyloid-related disease is elderly. In some embodiments, the individual has an early stage of an amyloid-related disease.

E. Prognosis

[0193] Also provided herein are methods of determining the prognosis of an individual having an amyloid-related disease comprising a) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; and c) comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time to determine the prognosis of the individual.

[0194] In some embodiments, the individual has an amyloid disorder is selected from the group consisting of AL, AH, Ap2M, ATTRv, ATTRwt, AA, AApoAI, AApoAII, AGel, ALys, ALECT2, AFib, ACys, ACal, AMed, AIAPP, APro, Alns, APrP, or Ap amyloidosis. In some embodiments, the individual has an early stage of an amyloid-related disease. In some embodiments, the individual has stage 1 amyloidosis. In some embodiments, the individual has systemic amyloidosis. In some embodiments, the individual has cardiac amyloidosis. In some embodiments, the individual has cardiac AL amyloidosis. In some embodiments, the individual has cardiac ATTR amyloidosis.

[0195] In some embodiments, the first time the amyloid-reactive peptide conjugated to a detectable label is administered and the second time the amyloid-reactive peptide conjugated to a detectable label is administered are between at least one week, two weeks, three weeks, one month, two months, three months, four months, five months, six months, seven months, eight months, nine months, ten months, eleven months, one year, two years, three years, four years, or five years apart. In some embodiments, the first time and the second time are at least two weeks apart. In some embodiments, the first time and the second time are at least one month apart. In some embodiments, the first time and the second time are at least three months apart.

[0196] In some embodiments, the prognosis of the individual with an amyloid-related disease has worsened. In some embodiments, the prognosis of the individual with an amyloid- related disease has improved.

[0197] In some embodiments, the prognosis is confirmed by a measure of the health related quality of life of the individual. In some embodiments, the prognosis is confirmed by the presence or amount of one or more biomarkers associated with the amyloid-related disease. In some embodiments, the prognosis is confirmed by a cardiac biopsy. In some embodiments, the prognosis is confirmed by additional amyloid imaging of the individual.

III. METHODS OF TREATMENT

[0198] Also provided herein are methods of treating an amyloid-related disease comprising; a) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; b) detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual; and c) administering a treatment for the amyloid-related disease if the amount of amyloid-reactive peptide is above a threshold.

[0199] Provided herein are methods of treating an amyloid-related disease in an individual with the amyloid-related disease at an early stage in an individual comprising administering an amyloid-reactive peptide conjugated to a detectable label to the individual and detecting the amount of detectable label at a tissue or organ of the individual and administering a treatment for the amyloid-related disease if the amount of amyloid-reactive peptide is above a threshold. In some embodiments, the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid-related disease, wherein the amyloid-related disease is in an early stage of the amyloid-related disease. In some embodiments, the amyloid-related disease is systemic amyloidosis. In some embodiments, the amyloid-related disease is cardiac amyloidosis. In some embodiments, the amyloid-reactive peptide conjugated to a detectable label is a peptide comprising the amino acids set forth in SEQ ID NO: 100, conjugated to ¹²⁴I. In some embodiments, the ¹²⁴I is bound to amino acid 4 of SEQ ID NO: 100.

[0200] The methods provided herein can be used for treating an amyloid-related disease at an early stage. In some embodiments, the methods can be used to treat an amyloid- related disease before the disease can be detected with traditional methods. In some embodiments, the individual has previously been diagnosed as not having a amyloid-related disease. In some embodiments, the methods have high sensitivity and specificity for detecting and treating an amyloid-related diseases at an early stage.

A. Administering an amyloid-reactive peptide

[0201] Some aspects of the present invention provide methods of treating an amyloid disease based upon detecting amyloids with an amyloid-reactive agent or detection dye. In some embodiments, provided herein is a method of treating an amyloid disease comprising administering an amyloid-reactive agent or detection dye, measuring the organ distribution of the amyloid-reactive agent or detection dye, and selecting a treatment based upon the type of disease.

[0202] In some embodiments, the methods of treating an amyloid disease comprising administering an amyloid-reactive agent or detection dye, and measuring the organ- specific SUV and/or SUVR of the amyloid-reactive agent for one or more organs. In some embodiments, the organ distribution pattern of the amyloid-reactive agent or dye indicates a type of amyloid disease. In some embodiments, the methods further comprise selecting a treatment based upon the type of amyloid disease.

[0203] In some embodiments, the method comprises obtaining an organ distribution pattern of an amyloid-reactive agent or detection dye, wherein the organ distribution pattern indicates a particular type of amyloid disease, and administering a treatment based upon the amyloid disease.

[0204] In some embodiments, the methods of treating an amyloid disease comprise administering an amyloid-reactive agent comprising an amyloid-reactive peptide conjugated to a detectable label. In some embodiments, the amyloid-reactive agent comprises a peptide, a fusion protein, a small molecule compound, or an antibody or fragment.

[0205] In some embodiments, the methods of treating an amyloid disease comprise administering an amyloid-reactive agent comprising an amyloid-reactive peptide conjugated to a detectable label. In some embodiments, the amyloid-reactive peptide is a peptide with amino acid sequence set forth as any one of SEQ ID NOS: 1-14. In some embodiments, the methods of treating an amyloid disease comprise an amyloid-reactive peptide with an amino acid sequence as set forth in SEQ ID NO: 13.

[0206] In some embodiments, the methods of treating an amyloid disease comprising administering an amyloid-reactive agent or detection dye, and measuring the organ- specific SUV and/or SUVR of the amyloid-reactive agent for one or more organs. In some embodiments, the methods of treating an amyloid disease comprise administering an amyloid-reactive agent comprising a detectable label to determine an organ distribution pattern. In some embodiments, the amyloid-reactive agent comprises a fluorescent label, chemiluminescent tag, or a radiolabel. In some embodiments, the amyloid-reactive agent comprises a radiolabel. In some embodiments, the radiolabeled amyloid-reactive agent is ¹²⁴I-p5+14. In other embodiments, the radiolabeled amyloid-reactive agent is florbetapir, flortaben, or flutemetamol. In some embodiments, the methods of treating an amyloid disease comprise p5+14. In some embodiments, the amyloid reactive agent is radiolabeled. In some embodiments, the radiolabel is ⁿC, ¹⁸F, ⁱⁿIn, "^mTc, and ¹²³I, ¹²⁴I, or ¹²⁵I. In some embodiments, the radiolabeled amyloid-reactive agent is a radiolabeled amyloid-reactive peptide. In some embodiments, the radiolabeled amyloid-reactive peptide is a ¹²⁴I-labelled amyloid-reactive peptide. In other embodiments, the method for diagnosing a type of amyloid disease comprise administering ¹²⁴I-p5+14. In other embodiments, the radiolabeled amyloid-reactive agent is florbetapir, flortaben, or flutemetamol.

[0207] In certain other embodiments, the amyloid-reactive agent comprises a fluorescent label. In some embodiments, the fluorescently-labelled amyloid-reactive agent is ThT. In some embodiments, the amyloid-reactive agent is administered parenterally, paracancerally, transmucosally, tansdermally, intramuscularly, intravenously, intradermally, subcutaneously, intraperitoneally, intraventricularly, or intracranially. In some instances, the amyloid-reactive agent is administered intravenously or intraperitoneally.

[0208] In some embodiments, the method further comprises administering potassium iodide to the individual. The potassium iodide may protect the individual’s thyroid gland. In some embodiments, the potassium iodide is administered orally. In some embodiments, 130 mg of potassium iodide is administered for 7 days starting one day before administration of the amyloid-reactive agent. In some embodiments, 130 mg of potassium iodide is administered for 3 days starting the day of the administration of the amyloid-reactive agent, for example about 30 minutes before the administration of the amyloid-reactive agent.

B. Detecting the amount of amyloid

[0209] In some embodiments, the methods of treating an amyloid disease comprise administering an amyloid-reactive agent or detection dye, and measuring the organ- specific SUV and/or SUVR of the amyloid-reactive agent for one or more organs. In some embodiments, the methods of treating an amyloid disease comprise measuring the organ distribution pattern of the amyloid-reactive agent for one or more organs. In some embodiments, the methods for treating the type of amyloid disease comprise measuring the organ- specific SUV and/or SUVR of the amyloid-reactive agent in one or more of lung, fat, heart, kidney, pancreas, joints, spine, liver, spleen, adrenal gland, bone lesions, choroid plexus, pituitary gland, uterus, bone marrow, musculoskeletal tissue, gastrointestinal, and prostate gland. In some embodiments, the one or more organs are heart, spleen, liver, or kidney. In some embodiments, the step of measuring the organ distribution pattern of the amyloid-reactive agent in one or more organ comprise determining an organ uptake value for each organ. In some embodiments, the organ uptake value is a standard uptake value for each organ. In some embodiments, the standard uptake value is determined as the ratio of the amount of amyloid-reactive agent detected in an organ, and the amount of amyloid-reactive agent detected in blood. In some embodiments, the organ uptake value is indicative of the organ distribution pattern of the amyloid-reactive agent or detection dye.

[0210] In some embodiments, the measuring the organ-specific SUV and/or SUVR of the amyloid-reactive agent comprises the analysis of imaging data generated by PET, CT, MRI, SPECT, PET/CT, PET/MRI, or other imaging techniques. In some embodiments, the step of measuring the organ-specific SUV and/or SUVR of the amyloid-reactive agent comprises analysis of images by the spatial location of regions of interest.

[0211] In other embodiments, the step of measuring the organ distribution pattern of the amyloid-reactive agent in one or more organ comprises calculating an organ-to-organ ratio for two or more organs. In some embodiments, the step of calculating an organ-to-organ ratio for two or more organs comprises calculating the ratio between the organ uptake value for a first organ and the organ uptake value for a second organ. In some instances, the organ-to-organ ration is selected from the group consisting of liver-to-heart, spleen-to-heart, spleen-to-liver, spleen-to-kidney, kidney-to-heart, and kidney-to-liver. In some instances, the organ-to-organ ratio is the heart-to- spleen ratio. In some embodiments, the ratio is the inverse of any of these ratios.

[0212] In some embodiments, the organ distribution pattern indicates a type of amyloid disease. In some embodiments, the organ distribution pattern is used to select a particular treatment based upon a type of amyloid disease. In some embodiments, the method further comprises providing a diagnosis of a type of amyloid disease based upon the organ distribution pattern. In some embodiments, a particular organ distribution pattern is indicative of a particular type of amyloid disease. For example, in some embodiments, the heart to spleen, heart to liver, spleen to liver, spleen to kidney, kidney to heart, or kidney to liver ratio is used to diagnose ATTR. In some embodiments, the heart to spleen, heart to liver, spleen to liver, spleen to kidney, kidney to heart, or kidney to liver ratio is used to diagnose ALECT2. In some embodiments, the heart to spleen, heart to liver, spleen to liver, spleen to kidney, kidney to heart, or kidney to liver ratio is used to diagnose AL.

C. Administering a treatment

[0213] In some embodiments, the method comprises treating or selecting a treatment for an amyloid-related disease in an individual. Some example amyloid diseases that can be diagnosed and/or treated with the methods disclosed herein include, but are not limited to, AA amyloidosis, AL amyloidosis, AH amyloidosis, Ap amyloidosis, ATTR amyloidosis, ALECT2 amyloidosis, and IAPP amyloidosis of type II diabetes, Alzheimer’s disease, thyroid tumors, Parkinson’s disease, a tauopathy, senile systemic amyloidosis, familial hemodialysis, senile systemic aging, aging pituitary disorder, iatrogenic syndrome, reactive chronic inflammation, thyroid tumors, myeloma or other forms of cancer. In some embodiments, the methods of treating an amyloid disease comprise selecting a treatment for a systemic amyloidosis. In some embodiments, the methods of treating an amyloid disease comprise selecting a treatment for AL amyloidosis, ATTR amyloidosis, or ALECT2 amyloidosis. In some embodiments, the treatment is a targeted therapy for an ATTR amyloidosis, an AL amyloidosis, or an ALECT2 amyloidosis. In some embodiments, the methods of treating an amyloid disease comprise selecting a treatment for cardiac amyloidosis. In some embodiments, the methods of treating an amyloid disease comprise selecting a treatment for cardiac AL amyloidosis. In some embodiments, the methods of treating an amyloid disease comprise selecting a treatment for cardiac ATTR amyloidosis. In some embodiments, the amyloid-related disease is at an early stage. In some embodiments, the amyloid related disease is an early stage amyloid-related disease.

[0214] In some embodiments, the method comprises treating or selecting treatment for an amyloid related disease in an individual suspected of having the amyloid-related disease. In some embodiments, an individual is suspected of having an amyloid-related disease, but has not been diagnosed with the amyloid-related disease. In some embodiments, the individual has not undergone a diagnostic evaluation for the amyloid related disease. In some embodiments, the individual has undergone diagnostic evaluation for the amyloid-related disease and the diagnostic evaluation did not detect the amyloid-related disease. In some embodiments, the individual has not been diagnosed according to the Mayo Clinic System. In some embodiments, the individual suspected of having an amyloid-related disease displays symptoms of an amyloid- related disease. Alternatively, in some embodiments, the individual at risk of developing an amyloid-related disease does not display symptoms of an amyloid-related disease. In some embodiments, individual suspected of having an amyloid-related disease has a genetic predisposition to an amyloid-related disease. In some embodiments, individual suspected of having an amyloid-related disease has a family history of any amyloid-related disease. In some embodiments, individual suspected of having an amyloid-related disease is elderly. In some embodiments, the individual has an early stage of an amyloid-related disease.

[0215] In some embodiments, the treatment is a small molecule, an antibody, a peptide, a protein, a nucleic acid, and/or a gene therapy. In some embodiments the treatment is a targeted treatment that is specific a particular type of amyloid disease.

[0216] In some embodiments, the treatment is an antibody-peptide fusion comprising an antibody-peptide fusion protein comprising a second amyloid-reactive peptide and an antibody that binds to amyloid fibrils. In some embodiments, the second amyloid-reactive peptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1-14 comprising 0, 1, 2, 3, or 4 amino acid substitutions, insertions, or deletions. In some embodiments, the second amyloid-reactive peptide comprises the amino acid sequence set forth in SEQ ID NO: 2. In some embodiments, the antibody-peptide fusion protein comprises: (i) an amyloid-reactive peptide comprising the amino acid sequence set forth in SEQ ID NO:2; and (ii) an antibody that binds to a human amyloid fibrils.

[0217] In some embodiments, the antibody that binds to a human amyloid fibril comprises a heavy chain and a light chain. In some embodiments, the antibody that binds to a human amyloid fibril comprises a heavy chain variable region (VH) and the light chain of the antibody comprises a light chain variable region (VL) according to Table 2. In some embodiments, the VH comprises the amino acid set for in SEQ ID NO: 102. In some embodiments, the VL comprises the amino acid set for in SEQ ID NO: 101.

Table 2: Exemplary Antibody VH and VL

[0218] In some embodiments, the heavy chain of the antibody comprises a heavy chain variable region (VH) and the light chain of the antibody comprises a light chain variable region (VL), wherein the VH and HV comprise the CDR according to Table 3. In some embodiments, the heavy chain of the antibody comprises a heavy chain variable region (VH) and the light chain of the antibody comprises a light chain variable region (VL), wherein the VH comprises a CDR-H1 comprising the amino acid sequence set forth in SEQ ID NO: 106, a CDR- H2 comprising the amino acid sequence set forth in SEQ ID NO: 107, and a CDR-H3 comprising the amino acid sequence set forth in SEQ ID NO: 108, and the VL comprises a CDR-L1 comprising the amino acid sequence set forth in SEQ ID NO: 103, a CDR-L2 comprising the amino acid sequence set forth in SEQ ID NO: 104, and a CDR-L3 comprising the amino acid sequence set forth in SEQ ID NO: 105.

Table 3:Exemplary Antibody CDRs

[0219] In some embodiments, the amyloid-reactive peptide and antibody are linked at the C-terminal end of the light chain, and wherein the amyloid-reactive peptide is linked to the antibody via a spacer comprising an amino acid sequence: VSPSV (SEQ ID NO:83). In some embodiments, the antibody-peptide fusion may be any of the modified immunoglobulins described in U.S. Patent Publication 12,030,934B2.

[0220] In some embodiments, the treatment is a targeted therapy for an ATTR amyloidosis, an AL amyloidosis, or an ALECT2 amyloidosis. In some embodiments, the treatment is a targeted therapy for ATTR amyloidosis. In some embodiments, the treatment comprises a TTR tetramer stabilizer. In some embodiments, the TTR tetramer stabilizer is epigallocatechin-3-gallate (EGCG), AG- 10, CHF5074, tafadimis, or diflunisal. In some embodiments, the treatment comprises an antibody or fragment that binds misfolded TTR. In some embodiments, the antibody is PRX004. In some embodiments, the treatment comprises an oligonucleotide. In some embodiments, the oligonucleotide is a TTR silencer. In some embodiments, the TTR silencer is patisiran (ALN-TTR02), vutrisiran, inotersen, or AKCEA- TTR-LRx. In some embodiments, the treatment comprises an ATTR amyloid disruptor. In some embodiments, the treatment comprises doxycycline, tauroursodeoxycholic acid, or serum amyloid P (SAP). In some embodiments, the treatment comprises an organ transplant. In some embodiments, the treatment comprises a liver transplant.

[0221] In other embodiments, the treatment is a targeted therapy for AL amyloidosis. In some embodiments, the treatment comprises bortemozib, ixazomib, or cazilfomib. In some embodiments, the treatment comprises an antibody or fragment. In some embodiments, the treatment comprises daratumab, CAEL-101, elotuzumab, or belantamab mafodotin. In some embodiments, the treatment comprises a stem cell therapy. In some embodiments, the treatment comprises a corticosteroid. In some embodiments, the corticosteroid is dexamethasone.

[0222] In some embodiments, the method is used to eliminate a potential therapy for a patient having amyloidosis. In some embodiments, the method is used to diagnose one type of amyloidosis and eliminate therapies for other types of amyloidosis. In some embodiments, the method is used to diagnose ALECT2 and eliminate therapies for AL or ATTR amyloidosis.

[0223] In some embodiments, the method is used to differentiate types of amyloidosis in order to develop therapies specific for a specific type of amyloidosis. For example in some embodiments, the method is used to identify individuals with ALECT2 amyloidosis and develop a therapy specific to ALECT2 amyloidosis.

[0224] In some embodiments, provided herein, are methods of monitoring the treatment of an amyloid-related disease in an individual comprising; a) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloidreactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b) administering a treatment for an amyloid-related disease; c) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; and d) comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time to determine whether the treatment is effective.

[0225] In some embodiments, the first time the amyloid-reactive peptide is administered and the second time the amyloid-reactive peptide is administered are between at least one week, two weeks, three weeks, one month, two months, three months, four months, five months, six months, seven months, eight months, nine months, ten months, eleven months, one year, two years, three years, four years, or five years apart. In some embodiments, the first time and the second time are at least two weeks apart. In some embodiments, the first time and the second time are at least one month apart. In some embodiments, the first time and the second time are at least three months apart.

[0226] In some embodiments, provided herein, are methods of selecting a treatment for an amyloid-related disease in an individual comprising; a) administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b) detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein if amyloid is detected in the heart a treatment for the amyloid-related disease is administered and wherein if amyloid is not detected in the heart, an alternative therapy is administered.

IV. KITS

[0227] Some aspects of the invention provide kits for diagnosing or detecting a type of amyloid disease in an individual with the methods described herein.

[0228] In some embodiments, the kit comprises an amyloid-reactive agent and instructions for use. In some embodiments, the amyloid-reactive agent comprising a detectable label. In some embodiments, the amyloid-reactive agent is ¹²⁴I-p5+14. In some embodiments the amyloid reactive agent comprises an amino acid sequence comprising SEQ ID NO: 13.

[0229] In some embodiments, the radiolabel is ⁿC, ¹⁸F, ⁱⁿIn, "^mTc, ¹²³I, ¹²⁴I, or ¹²⁵I. In some embodiments, the radiolabeled amyloid-reactive agent is a radiolabeled amyloidreactive peptide. In some embodiments, the radiolabeled amyloid-reactive peptide is a ¹²⁴I- labelled amyloid-reactive peptide. In other embodiments, the method for diagnosing a type of amyloid disease comprise administering ¹²⁴I-p5+14. In other embodiments, the radiolabeled amyloid-reactive agent is florbetapir, flortaben, or flutemetamol. [0230] In some embodiments, the instructions comprises instructions for detecting the amyloid reactive agent in one or more organs. In some embodiments the amyloid reactive agent is detected in blood, heart, lungs, kidney, or spleen.

[0231] In some embodiments, the kit comprises instructions for calculating an organspecific SUV. In some embodiments, the kit comprises instructions for calculating an organspecific SUVR. In some embodiments, the kit comprises instructions for calculating a SUVR ratio for one or more organs. In some embodiments, a SUVR is calculated using a blood pool as a reference tissue. In some embodiments, the SUVR is calculated for each organ by dividing the amount of amyloid detection agent or dye in the organ by the blood pool ratio. In some embodiments, the blood pool is a vein or artery. In some embodiments, the blood pool is the lumen of the thoracic aorta.

[0232] In some embodiments, the instructions comprise instructions for determining an organ to organ ratio. In some embodiments, the organ to organ ratio is the liver to heart, spleen to heart, spleen to liver, spleen to kidney, kidney to heart, kidney to liver, or the inverse of any of these ratios.

[0233] In some embodiments, the kit further comprises instructions for providing a diagnosis based upon the organ- specific SUV or SUVR. In some embodiments, the kit comprises instructions for providing a diagnosis based upon the organ to organ ratio.

[0234] In some embodiments, the kit comprises a therapeutic agent for treating an amyloid disease.

EXEMPLARY EMBODIMENTS

1. A method of diagnosing an amyloid-related disease in an individual at risk for developing the amyloid-related disease comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b. detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid disease. The method of embodiment 1, wherein the individual is determined to be at risk for an amyloid-related disease based upon the presence of a genetic mutation, having multiple myeloma, having amyloid positive laminectomy tissue, having an amyloid positive tissue from carpal tunnel release surgery, having a monoclonal gammopathy of unknown significance (MGUS), having heart failure with preserved ejection fraction (HFpEF), having heart failure with reduced ejection fraction (HFrEF), being from susceptible ethnic populations, or being elderly. The method of embodiment 2, wherein the genetic mutation is in the transthyretin protein. The method of embodiment 2, wherein the genetic mutation is in the fibrinogen ex protein. The method of any one of embodiment 1-3, wherein the individual does not have symptoms of amyloidosis. The method of any one of embodiments 1-3, wherein the individual has neuropathic symptoms of an amyloid disease. A method of diagnosing an amyloid-related disease in an individual suspected of having an amyloid-related disease comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b. detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid disease. A method of determining prognosis of an individual having an amyloid-related disease comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; and c. comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time to determine the prognosis of the individual. The method of embodiment 8, wherein the prognosis of an individual having an amyloid- related disease is based on detecting an amount of amyloid-reactive peptide in the heart alone. The method of embodiment 8, wherein the prognosis of an individual having an amyloid- related disease is based on detecting an amount of amyloid-reactive peptide in the heart and kidneys. The method of embodiment 8, wherein the prognosis of an individual having an amyloid- related disease is based on detecting an amount of amyloid-reactive peptide in the heart, kidneys, and all other organs. A method of treating an amyloid-related disease comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; b. detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label in a tissue or organ of the individual ,and c. administering a treatment for the amyloid-related disease if the amount of amyloid-reactive peptide is above a threshold. A method of monitoring treatment of an amyloid-related disease in an individual comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b. administering a treatment for an amyloid-related disease; c. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; and d. comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time to determine whether the treatment is effective. The method of any one of embodiments 1-13, further comprising administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time, optionally a third time a fourth time, and/or a fifth time. The method embodiments 13 or 14, wherein the first time and the second time are at least six weeks apart. A method of selecting a treatment for an amyloid-related disease in an individual comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b. detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein if amyloid is detected in the heart a treatment for the amyloid-related disease is administered and wherein if amyloid is not detected in the heart, an alternative therapy is administered. A method of managing the treatment for an amyloid-related disease in an individual comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b. administering a treatment for an amyloid-related disease; c. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; and d. comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time. e. adjusting the treatment for the amyloid-related disease. The method of embodiment 17, wherein if the amyloid disease is stable between the first and second times treatment is be modified. The method of embodiment 18, wherein if the amyloid burden increases treatment is reinitiated. The method of any one of embodiments 1-19, wherein the amyloid-reactive peptide comprises SEQ ID NO: 13. The method of any one of embodiments 1-20, wherein the detectable label is a radiolabel. The method of any one of embodiments 1-21, wherein the detectable label is selected from the group consisting of ⁿC, ¹⁸F, ^{n i}In, "^mTc, ⁸⁹Zr, ⁶⁸Ga, and ¹²³I, ¹²⁴I, and ¹²⁵I. The method of any one of embodiments 1-22, wherein the detectable label is ¹²⁴I. The method of any one of embodiments 1-23, comprising administering a dose of about

0.1 to about 25 mCi of ¹²⁴I-labeled amyloid-reactive peptide to the individual. The method of any one of embodiments 1-24, comprising administering a dose of about 0.3 mCi, 1 mCi, or about 2 mCi of ¹²⁴I-labeled amyloid-reactive peptide to the individual. The method of any one of embodiments 1-25, comprising administering a dose of about 20 mCi of Tc-99 to the individual. The method of any one of embodiments 1-26, comprising administering about 0.3 mg, 1 mg, 1.5 mg, or about 2 mg of amyloid-reactive peptide to the individual. The method of any one of embodiments 1-27, wherein the amyloid-reactive peptide is administered intravenously. The method of any one of embodiments 1-28, further comprising determining an organspecific standard uptake value ratio for an organ within an individual. The method of embodiment 29, wherein the organ- specific SUVR for the individual is selected from the group consisting of SUVR mean, SUVR max, and SUVR peak. The method of any one of embodiments 1-30, further comprising determining an organspecific SUV for the individual. The method of embodiment 31, wherein the organ- specific SUV for the individual is selected from the group consisting of SUV mean, SUV max, and SUV peak. The method of any one of embodiments 1-32, further comprising determining an organspecific percent injected dose/gram (%ID) for the individual. The method of any one of embodiments 1-33, wherein the amyloid-reactive peptide has a sensitivity of at least 90%. The method of any one of embodiments 1-34, wherein the sensitivity is about 99% or about 100%. The method of any one of embodiments 1-35, further comprising determining one or more health related quality of life measures for the individual. The method of any one of embodiments 1-36, further comprising detecting one or more biomarkers associated with the amyloid-related disease. The method of embodiment 37, wherein the biomarker associated with amyloid-related disease is selected from the group consisting of Troponin T, NTproBNP, urine protein levels, UACR, EGFR, and alkaline phosphatase levels. The method of any one of embodiments 1-38, wherein the tissue or organ of the individual is selected from the group consisting of lung, fat, heart, kidney, pancreas, joints, spine, liver, spleen, adrenal gland, bone lesions, choroid plexus, pituitary gland, uterus, bone marrow, musculoskeletal tissue, gastrointestinal, and prostate gland. The method of any one of embodiments 1-39, further comprising performing a cardiac biopsy if amyloid is detected in the heart. The method of any one of embodiments 1-40, further comprising performing additional amyloid imaging on the individual. The method of embodiment 41, wherein the additional amyloid imaging on the individual comprises ECHO, CMR, bone scintigraphy or positron emission tomography imaging. The method of embodiment 41, where in the additional amyloid imaging on the individual further comprises a tracer selected from the group consisting of "^mTc-PyP, "^mTc-DPD, "^mTc-HMDP, "^mTc-MDP other bone scintigraphy tracers, ¹²⁴I, and ¹⁸F- florbetapir, ¹⁸F-flutemetamol, and ¹⁸F-florbetaben. The method of any one of embodiments 1-43, wherein the diagnosis, prognosis, or response, is confirmed by a measure of the health-related quality of life of the individual, the presence or amount of one or more biomarkers associated with the amyloid-related disease, a cardiac biopsy, and/or additional amyloid imaging of the individual. The method of any one of embodiments 1-44, wherein the individual is diagnosed with amyloid cardiomyopathy. The method of any one of embodiments 1-45, wherein the individual is suspected of having amyloid cardiomyopathy. The method of any one of embodiments 1-46, wherein the amyloid-related disease is systemic or localized amyloidosis. The method of any one of embodiments 1-47, wherein the amyloid-reactive peptide has pan-amyloid specificity. The method of any one of embodiments 1-48, wherein the amyloid-reactive peptide binds to amyloid of immunoglobulin light chain (AL), immunoglobulin heavy chain (AH), P2- microglobulin (Ap2M), transthyretin (ATTR wild type; ATTR variant), apolipoprotein Al (AApoAI), apolipoprotein All (AApoAII), apolipoprotein AIV (AApoAIV), gelsolin (AGel), apolipoprotein C-II (AApoCII), apolipoprotein C-II (AApoCIII), lysozyme (ALys), leukocyte chemotactic factor (ALECT2), fibrinogen a variants (AFib), cystatin variants (ACys), calcitonin (ACal), lactadherin (AMed), islet amyloid polypeptide (AIAPP), prolactin (APro), insulin (Alns), prior protein (APrP); a-synuclein (AaSyn), tau (ATau), atrial natriuretic factor (AANF), IAAP, ALP4, or ALpi. The method of any one of embodiments 1-49, wherein the amyloid reactive peptide is detected using PET, PET/CT, gamma scintigraphy, SPECT, and/or SPECT/CT. The method of any one of embodiments 1-50, wherein the amyloid-related disease is selected from the group consisting of AL, AH, Ap2M, ATTRv, ATTRwt, AA, AApoAI, AApoAII, AApoCII, AApoCIII, AGel, ALys, ALECT2, AFib, ACys, ACal, AMed, AIAPP, APro, Alns, APrP, and Ap amyloidosis. The method of any one of embodiments 1-51, wherein the individual has a genetic predisposition to an amyloid-related disease. The method of any one of embodiments 1-52, wherein the individual has a family history of an amyloid-related disease. The method of any one of embodiments 1-53, wherein the individual is elderly. The method of any one of embodiments 1-54, wherein the individual has an early stage of an amyloid-related disease. The method of any one of embodiments 1-55, wherein the individual has an early stage of AL amyloidosis. The method of embodiment 56, wherein the early stage of AL amyloidosis is diagnosed according to the Mayo Clinic system. The method of embodiment 57, wherein the early stage of AL amyloidosis is stage 1 AL amyloidosis. The method of any one of embodiments 1-58, wherein the individual has an early stage of ATTR amyloidosis. The method of embodiment 59, wherein the early stage of ATTR amyloidosis comprises stage 1 ATTR amyloidosis. The method of any one of embodiments 1-11, 14-16, and 18-60, further comprising administering a therapy for the amyloid-related disease. The method of any one of embodiments 12-13, 17 and 61, wherein the therapy for the amyloid-related disease is selected from the group consisting of transthyretin stabilizers (e.g. tafamidis, acoramidis), transthyretin silencers (e.g. Patisiran, Inotersen, Vutrisiran, Eploetersen), gene editing approaches, anti-amyloid approaches utilizing monoclonal antibodies, treatments targeting plasma cell clones (e.g. Daratumumab, Bortezomib), and an antibody-peptide fusion comprising an antibody-peptide fusion protein comprising a second amyloid-reactive peptide and an antibody that binds to amyloid fibrils. The method of embodiment 62, wherein the second amyloid-reactive peptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1-14 comprising 0, 1, 2, 3, or 4 amino acid substitutions, insertions, or deletions. The method of embodiment 62 or 63, wherein the antibody-peptide fusion protein comprises a heavy chain and a light chain and wherein the amyloid-reactive peptide is linked to at the C-terminal end of the light chain of the antibody via a spacer. The method of any one of embodiments 62-64, wherein the antibody-peptide fusion protein comprises:

(i) an amyloid-reactive peptide comprising the amino acid sequence set forth in SEQ ID NO: 2; and

(ii) an antibody that binds to a human amyloid fibrils, wherein the antibody comprises a heavy chain and a light chain, wherein the heavy chain of the antibody comprises a heavy chain variable region (VH) and the light chain of the antibody comprises a light chain variable region (VL), wherein the VH comprises a CDR-H1 comprising the amino acid sequence set forth in SEQ ID NO: 106, a CDR-H2 comprising the amino acid sequence set forth in SEQ ID NO: 107, and a CDR-H3 comprising the amino acid sequence set forth in SEQ ID NO: 108, and the VL comprises a CDR-L1 comprising the amino acid sequence set forth in SEQ ID NO: 103, a CDR-L2 comprising the amino acid sequence set forth in SEQ ID NO: 104, and a CDR-L3 comprising the amino acid sequence set forth in SEQ ID NO: 105; wherein the amyloid-reactive peptide and antibody are linked at the C-terminal end of the light chain, and wherein the amyloid-reactive peptide is linked to the antibody via a spacer comprising an amino acid sequence set forth in SEQ ID NO:83. The method of any one of embodiments 1-65, wherein a peptide comprising the amyloidreactive peptide and an N-terminal leader sequence is administered to the individual. The method of embodiment 66, wherein the peptide comprising the amyloid reactive peptide comprises the amino acid sequence set forth in SEQ ID NO: 100. The method of embodiment 67, wherein the detectable label is bound to one or more amino acids at positions 1 to 6 of the amino acid sequence set forth in SEQ ID NO: 100. 9. The method embodiment 68, wherein the detectable label is ¹²⁴I. 0. The method of embodiment 69, wherein the ¹²⁴I is bound to amino acid 4 of SEQ ID NO: 100. 1. A peptide comprising the amino acid set forth in SEQ ID NO: 100, wherein the peptide comprises a detectable label bound to one or more amino acids at positions 1 to 6. 2. The peptide of embodiment 71, wherein the detectable label is ¹²⁴I. 3. The peptide of embodiment 72, wherein the ¹²⁴I is bound to amino acid 4 of SEQ ID NO: 100. A. A method of diagnosing an amyloid-related disease at an early stage in an individual at risk for developing the amyloid-related disease comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b. detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid-related disease, wherein the amyloid-related disease is in an early stage of the amyloid-related disease. A. The method of embodiment 1A, wherein the individual is determined to be at risk for an amyloid-related disease based upon the presence of a genetic mutation, having multiple myeloma, having amyloid positive laminectomy tissue, having an amyloid positive tissue from carpal tunnel release surgery, having a monoclonal gammopathy of unknown significance (MGUS), having heart failure with preserved ejection fraction (HFpEF), having heart failure with reduced ejection fraction (HFrEF), being from susceptible ethnic populations, or being elderly. A. The method of embodiment 2A, wherein the genetic mutation is in the transthyretin protein. A. The method of embodiment 2A, wherein the genetic mutation is in the fibrinogen ex protein. A. The method of any one of embodiments 1A-3A, wherein the individual does not have symptoms of amyloidosis. A. The method of any one of embodiments 1A-3A, wherein the individual has neuropathic symptoms of an amyloid disease. A. The method of any of embodiments 1A-6A, wherein the individual has previously been diagnosed as not having an amyloid related disease. A. A method of diagnosing an amyloid-related disease at an early stage in an individual suspected of having an amyloid-related disease comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b. detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid-related disease, wherein the amyloid-related disease is in an early stage of the amyloid-related disease.. A. A method of determining prognosis of an individual having an amyloid-related disease at an early stage comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; and c. comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time to determine the prognosis of the individual, wherein the amyloid-related disease is in an early stage of the amyloid-related disease.. A. The method of embodiment 9A, wherein the prognosis of an individual having an amyloid-related disease is based on detecting an amount of amyloid-reactive peptide in the heart alone. A. The method of embodiment 9A, wherein the prognosis of an individual having an amyloid-related disease is based on detecting an amount of amyloid-reactive peptide in the heart and kidneys. A. The method of embodiment 9A, wherein the prognosis of an individual having an amyloid-related disease is based on detecting an amount of amyloid-reactive peptide in the heart, kidneys, and all other organs. A. A method of treating an amyloid-related disease in an individual with the amyloid- related disease at an early stage comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; b. detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label in a tissue or organ of the individual ,and c. administering a treatment for the amyloid-related disease if the amount of amyloid-reactive peptide is above a threshold. A. The method of embodiment 13A, wherein the individual is suspected of having the amyloid-related disease. A. A method of monitoring treatment of an amyloid-related disease in an individual with the amyloid-related disease at an early stage comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b. administering a treatment for an amyloid-related disease; c. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; and d. comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time to determine whether the treatment is effective. A. The method of any one of embodiments 1A-15A, further comprising administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time, optionally a third time a fourth time, and/or a fifth time. A. The method embodiment 15A or 16A, wherein the first time and the second time are at least six weeks apart. A. A method of selecting a treatment for an amyloid-related disease in an individual comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b. detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein if amyloid is detected in the heart a treatment for the amyloid-related disease is administered and wherein if amyloid is not detected in the heart, an alternative therapy is administered. A. A method of managing the treatment for an amyloid-related disease in an individual comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b. administering a treatment for an amyloid-related disease; c. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; and d. comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time. e. adjusting the treatment for the amyloid-related disease. A. The method of embodiment 19A, wherein if the amyloid disease is stable between the first and second times treatment is be modified. A. The method of embodiment 20A, wherein if the amyloid burden increases treatment is reinitiated. A. The method of embodiments 9A-12A and 14A-21A, wherein the amount of amyloidreactive peptide above a threshold indicates that the individual has the amyloid-related disease. A. The method of embodiment 22A, wherein the amyloid-related disease is in an early stage of the amyloid-related disease. A. The method of any one of embodiments 1A-23A, wherein the amyloid-reactive peptide comprises SEQ ID NO: 13. A. The method of any one of embodiments 1A-24A, wherein the detectable label is a radiolabel. A. The method of any one of embodiments 1A-25A, wherein the detectable label is selected from the group consisting of ⁿC, ¹⁸F, ⁱⁿIn, "^mTc, ⁸⁹Zr, ⁶⁸Ga, and ¹²³I, ¹²⁴I, and 125j A. The method of any one of embodiments 1A-26A, wherein the detectable label is ¹²⁴I. A. The method of any one of embodiments 1A-27A, comprising administering a dose of about 0.1 to about 25 mCi of ¹²⁴I-labeled amyloid-reactive peptide to the individual. A. The method of any one of embodiments 1A-28A, comprising administering a dose of about 0.3 mCi, 1 mCi, or about 2 mCi of ¹²⁴I-labeled amyloid-reactive peptide to the individual. A. The method of any one of embodiments 1A-29A, comprising administering a dose of about of aboutl mCi (±10%) of ¹²⁴I-labeled amyloid-reactive peptide to the individual. A. The method of any one of embodiments 1A-30A, comprising administering a dose of about 20 mCi of Tc-99 to the individual. A. The method of any one of embodiments 1A-31A, comprising administering about 0.3 mg, 1 mg, 1.5 mg, or about 2 mg of amyloid-reactive peptide to the individual. A. The method of any one of embodiments 1A-32A, wherein the amyloid-reactive peptide is administered intravenously. A. The method of any one of embodiments 1A-33A, further comprising determining an organ- specific standard uptake value ratio for an organ within an individual. A. The method of embodiment 34A, wherein the organ-specific SUVR for the individual is selected from the group consisting of SUVR mean, SUVR max, and SUVR peak. A. The method of any one of embodiments 1A-35A, further comprising determining an organ- specific SUV for the individual. A. The method of embodiment 36A, wherein the organ-specific SUV for the individual is selected from the group consisting of SUV mean, SUV max, and SUV peak. A. The method of any one of embodiments 1A-37A, further comprising determining an organ- specific percent injected dose/gram (%ID) for the individual. A. The method of any one of embodiments 1A-38A, wherein the sensitivity for detecting amyloid using the amyloid-reactive peptide is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 99% or at least 100%. A. The method of any one of embodiments 1A-39A, wherein the sensitivity is about 99% or about 100%. A. The method of any one of embodiments 1A-40A, wherein the specificity of the amyloid-reactive peptide is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 99% or at least 100%. A. The method of any one of embodiments 1A-41A, wherein the specificity of the amyloid-reactive peptide is about 99% or 100%. A. The method of any one of embodiments 1A-42A, further comprising determining one or more health related quality of life measures for the individual. A. The method of any one of embodiments 1A-43A, further comprising detecting one or more biomarkers associated with the amyloid-related disease. A. The method of embodiment 44A, wherein the biomarker associated with amyloid- related disease is selected from the group consisting of Troponin T, NTproBNP, urine protein levels, UACR, EGFR, and alkaline phosphatase levels. A. The method of any one of embodiments 1A-45A, wherein the tissue or organ of the individual is selected from the group consisting of lung, fat, heart, kidney, pancreas, joints, spine, liver, spleen, adrenal gland, bone lesions, choroid plexus, pituitary gland, uterus, bone marrow, musculoskeletal tissue, gastrointestinal, and prostate gland. A. The method of embodiments 1A-8A, 13A, and 22A-46A, wherein the threshold is an SUVR mean threshold value. A. The method of embodiment 47A, wherein the SUVR mean threshold value is approximately 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, or 1.6 if the organ or tissue is the liver, the SUVR mean threshold value is approximately 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, or 1.5 if the organ or tissue is the spleen, the SUVR mean threshold value is approximately 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, or 2.3 if the organ or tissue is the kidneys, the SUVR mean threshold value is approximately 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, or 1.7 if the organ or tissue is the pancreas, the SUVR mean threshold value is approximately 0.9, 1.0, 1.1, 1.2, 1.3, 1.4,

I.5, 1.6, 1.7, 1.8, 1.9, 2.0, or 2.1 if the organ or tissue is the heart or the SUVR mean threshold value is approximately 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, or 1.4 if the organ or tissue is the adrenal gland. A. The method of embodiment 48A, wherein the SUVR mean threshold value is 1.31 if the organ or tissue is the liver, the SUVR mean threshold value is 1.21 if the organ or tissue is the spleen, the SUVR mean threshold value is 1.88 if the organ or tissue is the kidneys, the SUVR mean threshold value is 1.40 if the organ or tissue is the pancreas, the SUVR mean threshold value is 1.19 if the organ or tissue is the heart or the SUVR mean threshold value is 1.35 if the organ or tissue is the adrenal gland. A. The method of embodiments 1A-8A, 13A, and 22A-46A, wherein the threshold is an SUVR max threshold value. A. The method of embodiment 50A, wherein the SUVR max threshold value is 10.6, 11,

II.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, or 16 if the organ or tissue is the liver, the SUVR max threshold value is 3.8, 4, 4.5, 5, 5.5, or 5.9 if the organ or tissue is the spleen, the SUVR max threshold value is 7.7, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, or 11.7 if the organ or tissue is the kidneys, the SUVR max threshold value is 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, or 11.4 if the organ or tissue is the pancreas, the SUVR max threshold value is 4.9, 5, 5.5, 6, 6.5, 7, or 7.5 if the organ or tissue is the heart or the SUVR max threshold value is 1, 1.1, 1.2, 1.3, 1.4, 1.5, or 1.6 if the organ or tissue is the adrenal gland. A. The method of embodiment 51 A, wherein the SUVR max threshold value is 13.26 if the organ or tissue is the liver, the SUVR max threshold value is 4.86 if the organ or tissue is the spleen, the SUVR max threshold value is 9.68 if the organ or tissue is the kidneys, the SUVR max threshold value is 9.48 if the organ or tissue is the pancreas, the SUVR max threshold value is 6.20 if the organ or tissue is the heart or the SUVR max threshold value is 1.31 if the organ or tissue is the adrenal gland. A. The method of any one of embodiments 1A-52A, further comprising performing a cardiac biopsy if amyloid is detected in the heart. A. The method of any one of embodiments 1A-53A, further comprising performing additional amyloid imaging on the individual. A. The method of any one of embodiments 1A-54A, further comprising performing additional amyloid imaging on the individual before administering the amyloid reactive peptide. A. The method of embodiment 55A, wherein the additional amyloid imaging on the individual comprises ECHO, CMR, bone scintigraphy or positron emission tomography imaging. A. The method of embodiment 56A, where in the additional amyloid imaging on the individual further comprises a tracer selected from the group consisting of "^mTc-PyP, "^mTc-DPD, "^mTc-HMDP, "^mTc-MDP other bone scintigraphy tracers, ¹²⁴I, and ¹⁸F- florbetapir, ¹⁸F-flutemetamol, and ¹⁸F-florbetaben. A. The method of any one of embodiments 1A-57A, wherein the diagnosis, prognosis, or response, is confirmed by a measure of the health-related quality of life of the individual, the presence or amount of one or more biomarkers associated with the amyloid-related disease, a cardiac biopsy, and/or additional amyloid imaging of the individual. A. The method of any one of embodiments 1A-58A, wherein the individual is diagnosed with amyloid cardiomyopathy. A. The method of any one of embodiments 1A-59A, wherein the individual is suspected of having amyloid cardiomyopathy. A. The method of any one of embodiments 1A-60A, wherein the amyloid-related disease is systemic or localized amyloidosis. A. The method of any one of embodiments 1A-61A, wherein the amyloid-related disease is cardiac amyloidosis. A. The method of any one of embodiments 1A-62A, wherein the amyloid-reactive peptide has pan-amyloid specificity. A. The method of any one of embodiments 1A-63A, wherein the amyloid-reactive peptide binds to amyloid of immunoglobulin light chain (AL), immunoglobulin heavy chain (AH), p2-microglobulin (Ap2M), transthyretin (ATTR wild type; ATTR variant), apolipoprotein Al (AApoAI), apolipoprotein All (AApoAII), apolipoprotein AIV (AApoAIV), gelsolin (A Gel), apolipoprotein C-II (AApoCII), apolipoprotein C-II (AApoCIII), lysozyme (ALys), leukocyte chemotactic factor (ALECT2), fibrinogen a variants (AFib), cystatin variants (ACys), calcitonin (ACal), lactadherin (AMed), islet amyloid polypeptide (AIAPP), prolactin (APro), insulin (Alns), prior protein (APrP); a- synuclein (AaSyn), tau (ATau), atrial natriuretic factor (AANF), IAAP, ALP4, or ALpi. A. The method of any one of embodiments 1A-64A, wherein the amyloid reactive peptide is detected using PET, PET/CT, gamma scintigraphy, SPECT, and/or SPECT/CT. A. The method of any one of embodiments 1A-65A, wherein the amyloid-related disease is selected from the group consisting of AL, AH, Ap2M, ATTRv, ATTRwt, AA, AApoAI, AApoAII, AApoCII, AApoCIII, AGel, ALys, ALECT2, AFib, ACys, ACal, AMed, AIAPP, APro, Alns, APrP, and Ap amyloidosis. A. The method of embodiment 66A, wherein the amyloid-related disease is cardiac AL amyloidosis. A. The method of embodiment 66A, wherein the amyloid-related disease is cardiac ATTR amyloidosis. A. The method of any one of embodiments 1A-68A, wherein the individual has a genetic predisposition to an amyloid-related disease. A. The method of any one of embodiments 1A-69A, wherein the individual has a family history of an amyloid-related disease. A. The method of any one of embodiments 1A-70A, wherein the individual is elderly. A. The method of any one of embodiments 1A-71A, wherein the individual has an early stage of an amyloid-related disease. A. The method of any one of embodiments 1A-72A, wherein the individual has an early stage of an systemic amyloidosis. A. The method of any one of embodiments 1A-73A, wherein the individual has an early stage of cardiac amyloidosis. A. The method of any one of embodiments 1A-74A, wherein the individual has an early stage of AL amyloidosis. A. The method of embodiment 75 A, wherein the early stage of AL amyloidosis is diagnosed according to the Mayo Clinic system. A. The method of embodiment 76A, wherein the early stage of AL amyloidosis is stage 1 AL amyloidosis. A. The method of any one of embodiments 1A-77A, wherein the individual has an early stage of ATTR amyloidosis. A. The method of embodiment 78A, wherein the early stage of ATTR amyloidosis comprises stage 1 ATTR amyloidosis. A. The method of any one of embodiments 1A-12A, 16A-18A, and 20A-79A, further comprising administering a treatment for the amyloid-related disease. A. The method of any one of 13A-15A, 19A and 80A, wherein the treatment for the amyloid-related disease is selected from the group consisting of transthyretin stabilizers (e.g. tafamidis, acoramidis), transthyretin silencers (e.g. Patisiran, Inotersen, Vutrisiran, Eploetersen), gene editing approaches, anti-amyloid approaches utilizing monoclonal antibodies, treatments targeting plasma cell clones (e.g. Daratumumab, Bortezomib), and an antibody-peptide fusion comprising an antibody-peptide fusion protein comprising a second amyloid-reactive peptide and an antibody that binds to amyloid fibrils. A. The method of embodiment 81 A, wherein the second amyloid-reactive peptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1- 14 comprising 0, 1, 2, 3, or 4 amino acid substitutions, insertions, or deletions. A. The method of embodiment 81A or 82A, wherein the antibody-peptide fusion protein comprises a heavy chain and a light chain and wherein the amyloid-reactive peptide is linked to at the C-terminal end of the light chain of the antibody via a spacer. A. The method of any one of embodiments 81A-83A, wherein the antibody-peptide fusion protein comprises: (i) an amyloid-reactive peptide comprising the amino acid sequence set forth in SEQ ID NO: 2; and

(ii) an antibody that binds to a human amyloid fibril, wherein the antibody comprises a heavy chain and a light chain, wherein the heavy chain of the antibody comprises a heavy chain variable region (VH) and the light chain of the antibody comprises a light chain variable region (VL), wherein the VH comprises a CDR-H1 comprising the amino acid sequence set forth in SEQ ID NO: 106, a CDR-H2 comprising the amino acid sequence set forth in SEQ ID NO: 107, and a CDR-H3 comprising the amino acid sequence set forth in SEQ ID NO: 108, and the VL comprises a CDR-L1 comprising the amino acid sequence set forth in SEQ ID NO: 103, a CDR-L2 comprising the amino acid sequence set forth in SEQ ID NO: 104, and a CDR-L3 comprising the amino acid sequence set forth in SEQ ID NO: 105; wherein the amyloid-reactive peptide and antibody are linked at the C-terminal end of the light chain, and wherein the amyloid-reactive peptide is linked to the antibody via a spacer comprising an amino acid sequence set forth in SEQ ID NO: 83. A. The method of any one of embodiments 1A-84A, wherein a peptide comprising the amyloid-reactive peptide and an N-terminal leader sequence is administered to the individual. A. The method of embodiment 85A, wherein the peptide comprising the amyloid reactive peptide comprises the amino acid sequence set forth in SEQ ID NO: 100. A. The method of embodiment 86A, wherein the detectable label is bound to one or more amino acids at positions 1 to 6 of the amino acid sequence set forth in SEQ ID NO: 100. A. The method embodiment 87A, wherein the detectable label is ¹²⁴I. A. The method of embodiment 88A, wherein the ¹²⁴I is bound to amino acid 4 of SEQ ID

NO: 100. 90A. The methods of any of embodiment 1A-89A, further comprising administering potassium iodide to the individual.

91 A. The method of embodiment 90A, wherein the administering potassium iodide comprises administering 130 mg of the potassium iodide to the patient for seven days starting one day before the administration of the amyloid reactive peptide.

92A. The method of embodiment 91 A, wherein the administering potassium iodide comprises administering 130 mg of the potassium iodide to the patient for three days starting about 30 minutes before the administration of the amyloid reactive peptide.

93A. The method of any of embodiment 90A-92A, wherein the administration of potassium iodide is oral administration.

94A. A peptide comprising the amino acid set forth in SEQ ID NO: 100, wherein the peptide comprises a detectable label bound to one or more amino acids at positions 1 to 6.

95A. The peptide of embodiment 94A, wherein the detectable label is ¹²⁴I.

96A. The peptide of embodiment 95A, wherein the ¹²⁴I is bound to amino acid 4 of SEQ ID NO: 100.

EXAMPLES

[0235] The following examples are included for illustrative purposes only and are not intended to limit the scope of the present disclosure.

[0236] The present disclosure is not intended to be limited in scope to the particular disclosed embodiments, which are provided, for example, to illustrate various aspects of the present disclosure. Various modifications to the compositions and methods described will become apparent from the description and teachings herein. Such variations may be practiced without departing from the true scope and spirit of the disclosure and are intended to fall within the scope of the present disclosure. Example 1: Cardiac Amyloid Detection by PET/CT Imaging of ¹²⁴I-p5+14

[0237] This example describes the safety and efficacy of a novel amyloid-reactive peptide, designated p5+14, labeled with iodine- 124, in patients with diverse types of systemic amyloidosis.

STUDY DESIGN

[0238] This was a multi-part, open-label study to assess the safety, dosimetry and biodistribution of ¹²⁴I-p5+14 peptide in patients with systemic amyloidosis of any type; pre- symptomatic subjects carrying a germline TTR mutation; and healthy subjects. In Part 5, a single patient underwent repeat imaging approximately two years apart (Table 5). Patients with systemic AL amyloidosis were initially recruited to assess radiation dosimetry prior to enrolling additional patients. Enrollment targets were not met due to premature termination of the study to allow transfer of the IND to a commercial partner for clinical development (Table 5).

[0239] This study was an exploratory Phase 1/Phase 2 evaluation of ¹²⁴I-p5+14 as an imaging agent for the safe and accurate detection of amyloid deposits in patients with systemic amyloidosis. The primary objective was to assess the safety and tolerability of the study agent using systemic and organ-specific measures of dosimetry (Part 1) and standard measures of safety (vital signs, adverse events, and clinical laboratory measures).

[0240] The secondary objectives were broadly designed to assess:

[0241] 1. Whether organ- specific retention of ¹²⁴I-p5+14 could be observed in anatomic sites where there was biopsy-proven or clinically suspected amyloid deposition in all patients with systemic amyloidosis and within each major amyloid-type patient subset, e.g., AL, ATTR, ALECT2.

[0242] 2. In appropriately evaluable patients, the correlation between the amount of uptake of ¹²⁴I-p5+14 (defined as the mean and maximum concentration per unit volume [Bq/cc] or SUVR) in the kidney and heart, based on PET data, with clinical metrics of organ function such as: serum NT proBNP, creatinine, BUN or eGFR.

[0243] 3. The distribution of ¹²⁴I-p5+14 in subjects without abnormal amyloid deposition, that is, in healthy controls.

[0244] 4. The biodistribution of ¹²⁴I-p5+14 in asymptomatic subjects with known pro amyloid mutations of transthyretin. [0245] 5. If changes in amyloid load in patients could be appreciated through repeat imaging.

[0246] The study enrolled n=50 patients with a diagnosed and identified type of systemic amyloidosis, 2 asymptomatic subjects with a confirmed mutant form of TTR at risk for amyloidosis (who were not evaluable and excluded from analysis of organ- and patient-based sensitivity measurements), and 5 healthy controls (a total of 57 unique subjects). In addition, one participant from Part 2 successfully underwent a repeat exposure to ¹²⁴I-p5+14 and followup imaging. The participants were not randomized or blinded with respect to their disease state. Every subject received the ¹²⁴I-p5+14 PET imaging agent. During evaluation of the PET/CT image data, the study Nuclear Medicine Physician (the reader) was blinded to the patient or subject diagnosis and suspected organ involvement.

[0247] This study comprised five parts. In Part 1 (n=3 patients with widespread AL amyloidosis), the patients participated in a radioactivity dose-escalation study to assess radiation dosimetry and pharmacokinetics. Patients received a single IV bolus of ¹²⁴I-p5+14 (< 2 mg of p5+14 peptide). Patient one was administered 0.31 mCi (0.84 mg p5+14), patient two 1.05 mCi (1.06 mg p5+14) and patient three 1.03 mCi (0.95 mg p5+14). Whole body and organ- specific dosimetry was estimated based on the imaging data using the OLINDA-EXM method (1).

[0248] In Parts 2, 3, and 4, a further 54 participants were enrolled and received a single IV infusion of ¹²⁴I-p5+14 (1.98 ± 0.19 mCi ¹²⁴I and 1.42 ± 0.19 mg p5+14). In Part 5, a single patient imaged during Part 2 received a second injection of ¹²⁴I-p5+14 (2.08 mCi and 1.49 mg p5+14) and a repeat PET/CT scan.

[0249] The radiolabeled drug product was synthetized using aseptic techniques in a biological safety cabinet in a certified clean room within the Radiochemistry Facility at the University of Tennessee Medical Center, Knoxville (study site). After testing for radiopurity, stability, bioactivity and endotoxin levels, the ¹²⁴I-p5+14 dose was formulated in <35 mL sterile phosphate buffered saline with 5% w/v human serum albumin (USP) as a stabilizing agent, and 0.5 mg/mL ascorbic acid (USP) as an antioxidant. Participants received an IV infusion of 30 mL of ¹²⁴I-p5+14 delivered at a flow rate of 3 mL/min followed by a 30 mL saline flush at the same rate. The iodine- 124 was purchased from 3D Imaging (Little Rock, AR) and was generated in compliance with information provided in DMF # 025853. Table 4: Subject Disposition

^aOne patient was deemed ineligible due to heparin use and four healthy volunteers were found ineligible due to comorbidities.

PATIENT IDENTIFICATION AND IMAGING PROTOCOL

[0250] The study required an initial prescreen of medical records, after obtaining a signed medical release, to confirm the diagnosis of amyloidosis and assess the clinical evidence for organ involvement in 13 predetermined organs and tissues (FIG. 1). Following written consent, on Day 1 participants underwent a physical exam and phlebotomy followed by initiation of a 7-day course of oral potassium iodide. Subjects received acetaminophen and antihistamine 30 min prior to a 30-mL IV infusion of ¹²⁴I-p5+14 at 3 mL/min followed by a 30 mL saline flush at the same rate. [0251] On Day 3, phlebotomy was again performed. Follow-up phone calls were performed at Day 9 and 28 in patients with systemic amyloid and presymptomatic subjects. Healthy subjects, recruited after 42 patients had been imaged, had safety follow up on Days 3, 9, 28, and 56 and provided blood samples on Days 28 and 56 (FIG. 1).

SUBJECT POPULATION

[0252] Subjects were recruited locally and from around the US. Patients included males and females >18 years of age with a diagnosis of amyloidosis of known type. Healthy subjects were >50 years of age with no gender or racial restrictions, no known germline mutation in the TTR gene, no diagnosis of amyloidosis or type 2 diabetes mellitus and no first- or second- degree relatives with confirmed or suspected familial amyloidosis. One patient with AL and evidence of positive organ uptake had repeat imaging after-24 months.

[0253] Due to the known interaction of peptide p5+14 with heparin, patients exposed to heparin within seven days prior to infusion were excluded.

[0254] A total of n=25 patients with AL amyloidosis (n=23 with systemic AL and n=2 with localized AL); n=20 patients with ATTR amyloidosis (n=15 ATTRv and n=5 ATTRwt); two (n=2) patients with ALECT2 amyloidosis; and (n=3) patients with other amyloid types were imaged (Table 3). Additionally, n=5 healthy volunteers and n=2 asymptomatic TTRv carriers were enrolled.

Table 5: Subject demographic characteristics at baseline

RADIOTRACER SYNTHESIS AND PET/CT IMAGING

[0255] Peptide p5+14 was synthesized by AmbioPharm Inc. (North Augusta, SC), supplied as a lyophilized powder in 3 mg aliquots, and stored at -20°C. Iodine- 124 was purchased from 3D Imaging (Little Rock, AR; DMF# 025853). Patient batches of radiotracer were prepared on the day of use in the UT Radiochemistry Facility using soluble iodogen as the oxidant. Images were acquired with a Siemens Biograph PET/CT (Siemens, Knoxville, TN) using a ~30-sec reduced-dose CT (120 kVp, 50 effective mAs). PET images were acquired initially from knees to ankles, using 2 x 10 min bed positions before imaging from crown to thighs using 5 min bed positions. Lastly, a 10 min gated cardiac PET image was acquired.

[0256] PET data were reconstructed using a 3D OSEM algorithm with attenuation and prompt gamma corrections, a 168 x 168 image matrix, and an image resolution of ~8 mm full width half maximum. CT data were reconstructed using a medium smoothing kernel and 4 mm reconstruction increments.

IMAGE INTERPRETATION

[0257] PET/CT images were visually evaluated for uptake in 13 organs and tissues using the XD General Oncology Review application in Mirada Medical DBx (Build 1.2.0.59). Maximum intensity projections (MIPs) and PET/CT images were prepared using Inveon Research Workplace (IRW) software (Ed. 4.2 [4.2.0.15], Siemens Preclinical Solutions). Evaluation of the PET/CT images was performed by a reader blinded to the clinical data. Uptake of ¹²⁴I-p5+14 in organs was quantified manually by measurement of radioactivity per unit volume (Bq/cc). The standard uptake value ratio (SUVR) was determined for all organs by scaling the mean radioactive concentration by the blood pool (radioactivity in the lumen of the thoracic aorta).

[0258] In patients with AL- or ATTR-associated amyloidosis, the correlation between the cardiac uptake of ¹²⁴I-p5+14 (SUVRmean) and contemporaneous serum NT-proBNP was assessed. Similar correlations were performed for renal radiotracer uptake and serum blood urea nitrogen (BUN), creatinine and eGFR.

ENDPOINTS

[0259] The primary endpoint was determination of radiation dosimetry and safety based on collection of adverse events (AEs), which were reported according to the Medical Dictionary for Regulatory Activities (MedDRA) after initial classification using CTCAE criteria. Additional efficacy-based secondary and exploratory endpoints and two measures of interest were also undertaken. ASSESSMENTS

[0260] No clinical assessments were performed as part of this study other than serum biomarker measurements. Safety assessments were performed before and after the infusion of ¹²⁴I-p5+14. Vital signs were collected immediately prior to infusion of the radiotracer and periodically for 50 mins thereafter. Blood was drawn for clinical chemistry, complete blood count, C-reactive protein, lactate dehydrogenase, and NTproBNP testing (FIG. 1). In healthy subjects, additional blood samples were drawn at 28 and 56 d post infusion to assess anti-p5+14 antibodies using an in-house pep tide-capture ELISA.

ESTIMATION OF AMYLOID ORGAN POSITIVITY

[0261] The truth standard for diagnosis and organ involvement in this study was derived from the medical record and based on standard methods of diagnosis. Tissue biopsy was performed in the majority of patients. Organ involvement was tabulated during prescreening. Cardiac amyloidosis was generally based on a combination of serum biomarkers (NT-proBNP), echocardiography, magnetic resonance imaging, nuclear imaging, and endomyocardial biopsy. Amyloid involvement in other organs relied on organ specific biopsies or remote biopsies combined with serum biomarkers.

STATISTICS

[0262] Sample size was dictated by the rarity of systemic amyloidosis in the population, the anticipated accrual rate, and the exploratory nature of the study. A comprehensive subset analysis of patients with AL and ATTR, and healthy volunteers, was not feasible given subject numbers. All subjects who completed the study were included in image analyses except for the presymptomatic participants for whom the image quality was deemed unacceptable.

[0263] The patient- and organ-based sensitivity was determined by comparing visual uptake of ¹²⁴I-p5+14 in abdominothoracic organs by PET/CT imaging with clinically known or anticipated organs involvement. Sensitivity and specificity (percent agreement) were calculated by Exact method and the 95% confidence interval (95% CI) calculated using Wilson-Brown method (Graphpad Prism v9.3.0). Patient-based sensitivity, (i.e., participants with a confirmed diagnosis of amyloidosis positive ¹²⁴I-p5+14 uptake in any organ or tissue) was similarly calculated. Cardiac specificity was assessed in the healthy subject cohort, where absence of amyloid was assumed based on recruitment criteria.

[0264] Comparison of cardiac ¹²⁴I-p5+14 uptake in patients and healthy subjects was performed using unpaired, two-tailed t-tests with ex = 0.05. The correlation between ¹²⁴I-p5+14 uptake in the kidney or heart (SUVRmean) and BUN (mg/dL), creatinine (mg/dL), eGFR, and serum NT-proBNP (pg/mL) was determined using a Spearman analysis (ex = 0.05). Calculations were performed using SPSS Version 28 (Armonk, NY: IBM Corp.) and Prism.

ETHICAL OVERSIGHT

[0265] The study protocol was granted to proceed by the US Food and Drug Administration and performed under the auspices of Investigational New Drug (IND) submission (IND# 132282). Further approval was obtained from the Institutional Review Board (IRB) at the UT Graduate School of Medicine (Knoxville, TN). All patients provided written consent for prescreening of medical records and the imaging protocol prior to participation in the study.

RESULTS

SUBJECT DISPOSITION

[0266] Fifty-seven (n=57) subjects were enrolled (Table 4). Healthy volunteers (n=5) and asymptomatic TTRv carriers (n=2) comprised the amyloid-free control group for the purpose of most analyses. The first three patients were administered 11.4 MBq, 38.9 MBq, and 38.1 MBq, respectively, and were imaged seven times over 48 h post injection. Subsequent subjects (n=54) were administered 73.3+7.0 MBq and 1.42+0.19 mg of peptide with PET/CT images acquired at 5.2 h (IQ, 4.93-5.42) post infusion. The initial n=22 patients were imaged also at ~24 h post injection but was discontinued to minimize the CT radiation dose, as the data did not add to the interpretation of findings at 5 h post injection. All subjects completed the study.

PATIENT DEMOGRAPHICS AND BASELINE CHARACTERISTICS

[0267] Fifty one percent (51%) of the subjects were male. The mean age of all subjects was 64.8+10.2 years. In the AL amyloidosis population, 52% (n=13/25) were X isotype, 40% (n=10/25) were K. Eight percent (n =2/25) were not reported (Table 5). Patients with ATTR amyloidosis comprised 25% ATTRwt (n=5/20). Eight different germline mutations were included in the ATTRv population, with most being T60A (n=6/20) (Table 5). Cardiac involvement in patients with AL or ATTR amyloidosis was clinically noted in 52% (n= 13/25) and 55% (n=l l/20), respectively. Cardiac amyloidosis was only clinically anticipated in one of the patients with other types of amyloidosis (ALys). In the AL patient cohort, extracardiac amyloid was noted in the medical record in the spleen (n=l/25), liver (n=3/25) and the kidneys (n=7/25).

RADIOTRACER PRODUCTION

[0268] Each batch of ¹²⁴Lp5+14 was assessed for reactivity with amyloid-like fibrils with the mean percent bound-peptide equal to 97.5 ± 1.5%. The mean radiopurity of ¹²⁴Lp5+14 in the formulated doses was 98.8 ± 0.7%. All other release criteria, specifically pyrogenicity, sterility, color, pH, peptide identity, peptide purity, and particulates, met release criteria.

DOSIMETRY AND PHARMACOKINETICS

[0269] The gender-averaged whole-body effective radiation dose was estimated to be 0.23 (± 0.02) mSv/MBq with the highest organ dose received by the urinary bladder (0.94 ± 0.25 mSv/MBq). Elimination of the radioactivity was principally via renal and gastrointestinal routes with rapid loss of radioactivity from the central compartment. The estimated whole blood elimination half-life was 21.9 ± 7.6 h.

CARDIAC UPTAKE AND ABDOMINOTHORACIC BIODISTRIBUTION OF ¹²⁴Lp5+14 IN HEALTHY SUBJECTS

[0270] In healthy subjects (n =5), radioactivity was observed in the stomach and urinary bladder as well as the parotid and salivary glands, renal pelvis, ureter, and saliva in the esophagus. In healthy subject number four, radioactivity in the liver and kidney was considered higher than blood pool background and consequently deemed positive in these sites (FIG. 2A). In the heart, there was no visible evidence of radioactivity in the LV or right ventricular (RV) walls, or IVS in any healthy subject (FIG. 2B). Visual evaluation of ¹²⁴Lp5+14 distribution therefore resulted in specificity (negative percent agreement) for the heart and spleen of 100%, and 80% for the liver and kidneys (Table 5). Table 6: Uptake of ¹²⁴I-p5+14 in four major organs in healthy subjects

CARDIAC UPTAKE OF 124I-p5+14 IN PATIENTS

[0271] Cardiac uptake of ¹²⁴I-p5+14 was readily visible by PET/CT imaging in patients with ATTR or AL amyloidosis (FIG. 3A) and in those with AApoAl and ALys- associated amyloidosis. Cardiac uptake of the radiotracer was observed in patients with known cardiac involvement, and in those for whom cardiac involvement had not been identified (FIG. 3B). In most cases, radioactivity was observed in the LV wall and IVS with variable involvement of the RV wall and atria.

[0272] The sensitivity of cardiac ¹²⁴I-p5+14 uptake was 93% (n=13/14, ([95% CI: 68.5-99.6]) and 100% (n=l 1/11, ([95% CI: 74.2-100]) in patients with AL and ATTR amyloidosis, respectively. For the entire patient population, the cardiac sensitivity was 96% (n=25/26, ([95% CI: 81.1-99.8]) (Table 6). Cardiac retention of ¹²⁴I-p5+14 was observed in 27% (n=3/l 1) of AL patients, and 67% (n=6/9) of ATTR patients who had no clinical evidence of cardiac involvement based on review of the medical records. Gated cardiac images were not evaluated.

Table 7: Amyloid Distribution Agreement Between Clinical Evaluation and ¹²⁴I-p5+14

Imaging Evaluation in Subjects with Systemic Amyloidosis for 13 Evaluated Organs and

Tissues

QUANTITATION OF CARDIAC ¹²⁴I-p5+14 UPTAKE AND CORRELATION WITH SERUM NTproBNP

[0273] There was no difference in the cardiac SUVRmean of the AL and ATTR patient cohorts (FIG. 4A). Cardiac uptake of radiotracer in patients with systemic amyloidosis was significantly higher than that of healthy subjects, (Fig. 4A). The cardiac SUVRmean in the PET positive (PET+) cohorts was significantly higher than PET negative (PET-) patients (FIG. 4A).

[0274] For patients with AL amyloidosis, a statistically significant correlation (rS=0.48. p=0.018) between cardiac SUVRmean and serum NTproBNP was observed (FIG. 4B). No correlation was observed for patients with ATTR amyloidosis (rS=0.28. p=0.231) (FIG. 4C). In a post hoc analysis of the AL amyloidosis patient data, the cardiac SUVRmean was scaled by the serum creatinine for each patient to account for variably impaired renal function. Comparison of this compound variable with serum NTproBNP resulted in a highly significant correlation (rS=0.61. p=0.0017) (FIG. 4D). No correlations were observed between renal SUVRmean and serum creatinine, BUN, or eGFR.

EXTRACARDIAC BIODISTRIBUTION OF ¹²⁴Lp5+14 IN PATIENTS

[0275] The binding of ¹²⁴I-p5+14 was visually appreciated in one or more of the n=13 predetermined organs in 94% (n=44/47, [95% CI: 82.8-97.8]) of enrolled patients (Table 6). Two patients (n=2) diagnosed with AL and one with ATTR had no positive visual uptake of ¹²⁴I- p5+14 in any evaluated organ or tissue. Extracardiac binding of ¹²⁴I-p5+14 was observed in the kidneys, liver, spleen, pancreas, lung, adrenal gland, bones and joints, subcutaneous and abdominal fat, pituitary gland, choroid plexus, and bone lesions (in a patient with multiple myeloma and AL amyloidosis) (FIGs. 5A-5B). Despite the low number of clinical observations, the sensitivity for liver and spleen amyloid for all patients was 100% (n=4/4, 95%CI: 51.0-100) and 100% (n=2/2, 95% CI: 17.8-100) (Table 6). The kidney, as the organ of excretion, had lower sensitivity of 79% (n=l l/14, 95% CI: 52.4-92.4) (Table 6). Uptake of ¹²⁴I-p5+14 in patients with AL was also observed in the spleen and liver in 37.5% (n=9/24) and 18% (n=4/22), respectively, of patients with no clinical evidence of organ-related involvement. In addition, uptake of ¹²⁴I-p5+14 was observed in the spleen (35%, n=7/20), liver (24%, n=5/20) and kidneys (45%, n=9/20) of patients with ATTR amyloidosis in the absence of clinical evidence of organ involvement.

IMMUNOGENICITY OF p5+14

[0276] There was no evidence of anti-peptide antibodies in the ELISA in any sample when compared to two control samples of normal human serum.

SAFETY

[0277] The safety analysis was conducted on all subjects. Overall, 124I-p5+14 was well tolerated, with no deaths, drug-related serious adverse events (SAEs), or treatment emergent adverse events (TEAEs) resulting in study discontinuation (Table 8). Only one patient (1.8%, n=l/57) experienced study drug related TEAEs, pruritus and dysuria, both of which resolved without sequelae. Approximately half (49.1%, n=28/57) of the subjects reported a non-study drug related TEAE, most of which were of mild severity.

Table 8: Overall summary of adverse events

DISCUSSION

[0278] Current anatomic imaging methods, including echocardiography and cardiac magnetic resonance imaging, provide valuable structural and functional information once a diagnosis of amyloidosis has been established. "^mTc-PyP and similar bone-seeking agents are used for detecting cardiac amyloid; however, they appear to bind microcalcifications associated with amyloid deposits (Dietemann S, Nkoulou R. Ann Nucl Med. 2019;33:624-628), and their relationship with amyloid fibrils is not well understood. Therefore, a non-invasive imaging method using a reagent that directly binds amyloid deposits, is quantifiable, and can detect cardiac amyloidosis before the onset of overt anatomic changes and organ dysfunction would be of significant clinical benefit.

[0279] Peptide p5+14 is a synthetic pattern recognition peptide that binds amyloid via multivalent electrostatic interactions (Antoni G, Lubberink M, Estrada S, el al. J Nucl Med. 2013;54:213-220). In preclinical studies, the peptide bound synthetic amyloid-like fibrils and diverse types of amyloid-laden tissue sections. When radiolabeled with iodine- 124, the peptide is suitable for PET/CT imaging, which affords quantitative, high-resolution biodistribution data. Iodine- 124 is a non-residualizing, cyclotron-produced radionuclide with a 4.2-day half-life that can be enzymatically stripped from the peptide by intracellular enzymes during renal catabolism, resulting in physiological uptake in the stomach lumen, salivary and thyroid glands (Cuddy SAM, Bravo PE, Falk RH, et al. JACC Cardiovasc Imaging. 2020;13:1325-1336). This process is exploited to permit amyloid imaging in the kidney, the organ of clearance.

[0280] This is the first-in-human Phase 1/2 study of ¹²⁴I-p5+14 enrolled patients with eight different types (sub-types) of amyloidosis - ALK, AL , ATTRwt, ATTRv, ALys, AGel, ALECT2 and AApoAl. The sensitivity of organ- specific uptake of radiotracer was assessed by comparison with data in the patients’ medical record, which served as the truth standard in this early-phase study. Incidental imaging findings were also recorded following visual review of the PET images. Overall, a dose of 2 mCi ¹²⁴I-p5+14 (~1.4 mg peptide) was well-tolerated, with no deaths or drug-related SAEs. The whole-body effective dose for a 1 mCi ¹²⁴I-p5+14 injection (8.9 mSv), which is being used in follow-on studies, is equivalent to many thallium-201 and technetium-99m cardiac evaluations (Genovesi D, Vergaro G, Giorgetti A, et al. JACC Cardiovasc Imaging. 2021;14:246-255). All patients diagnosed with amyloidosis in the study demonstrated visual uptake of ¹²⁴I-p5+14 in at least one abdominothoracic organ or tissue including the heart, apart from one patient with AL who was diagnosed with cutaneous amyloid nodules, and one with renal amyloidosis who responded well to therapy and was presumed to have complete regression of the amyloid deposits (18,19). A patient diagnosed with systemic ATTRwt amyloidosis, with peripheral neuropathy and a Congo red positive ligamentum flavum finding, was negative.

[0281] Cardiac uptake of the radiotracer was observed in 100% of patients with ATTR in whom clinical evidence supported a diagnosis of cardiac amyloidosis. Moreover, positive cardiac PET/CT imaging was observed in six ATTR patients with no clinical evidence of cardiac involvement. This included patients with negative "^mTc-PyP imaging and normal serum NTproBNP levels. These data suggest that PET/CT imaging of ¹²⁴I-p5+14 may detect early, presymptomatic cardiac amyloid.

[0282] Of the major abdominothoracic organs, the sensitivity (positive percent agreement) between clinical findings and ¹²⁴I-p5+14 imaging was strongest for the heart (96.2%; 95% CI: 80.4-99.9; n=26). The presence of cardiac amyloid was not confirmed contemporaneously, but relied on clinical reports in the medical record, which is a limitation of the study design, but suggests that cardiac amyloid persists even in patients responding to treatment. Incidental uptake of ¹²⁴I-p5+14 was observed in extracardiac sites by PET/CT imaging, notably in the liver and spleen of patients with AL amyloidosis, organs that commonly contain asymptomatic amyloid deposits (Martin EB, Williams A, Richey T, et al. Sci Rep. 2016;6:22695). Although considered principally a cardiac or neuropathic disorder, ATTR amyloidosis is a systemic pathology. PET/CT imaging of ¹²⁴I-p5+14 in patients with ATTR amyloidosis exhibited diverse anatomic uptake involving e.g., the lung, liver, kidney, pancreas, spheroid joints, spine, and abdominal fat. These data suggest that ¹²⁴I-p5+14 imaging can detect not only cardiac amyloidosis, but also extracardiac disease that may contribute to poor quality of life and impact the speed of cardiac amyloid removal in patients receiving amyloid-degrading therapeutics.

[0283] PET imaging is an intrinsically quantitative modality. Uptake of ¹²⁴I-p5+14 can be readily assessed by various analytical methods including determination of an organspecific SUVR, a semi-quantitative metric in PET. The ratio was used in this study to control for differences in radiotracer clearance rates, which may be significantly impacted by impaired renal function notably in patients with AL amyloidosis and in many of the less common types where renal involvement is ubiquitous. Mean cardiac SUVR measurements for the AL and ATTR populations in this study were indistinguishable. However, the AL, ATTR and other amyloid populations had significantly higher mean cardiac SUVRs as compared to the small cohort of healthy controls.

[0284] Serum NT-proBNP is a validated biomarker for overall survival in patients with AL amyloidosis. Cardiac retention of ¹²⁴I-p5+14 in these patients, but not those with ATTR, correlated positively and significantly with contemporaneous measurements. This correlation was increased when renal function, estimated by serum creatinine levels, was included in the analysis (Dorbala S, Ando Y, Bokhari S, et al. J Nucl Cardiol. 2020;27:659-673).

[0285] Current amyloid treatments have demonstrated a greater impact in patients in earlier stages of cardiac amyloidosis, therefore it is imperative to diagnose patients early in their disease. An agent that could directly detect amyloid deposits prior to symptom onset, or when symptoms are mild, could be advantageous. As new amyloid-clearing therapies are developed, a tool that can directly measure amyloid load, quantify changes, and demonstrate efficacy would be invaluable. A non-invasive and quantitative technique, such as PET/CT imaging with ¹²⁴I- p5+14, that can detect and monitor cardiac as well as extracardiac deposits would be particularly useful.

CONCLUSIONS

[0286] The data from this first-in-human study support the overall safety and efficacy of ¹²⁴I-p5+14 for detecting cardiac amyloidosis, as well as systemic amyloid deposits. Based on these data, orphan designation for the diagnosis of AL and ATTR amyloidosis has been granted in the US and Europe.

Example 2: Inclusion and Exclusion Criteria

[0287] This example describes the inclusion and exclusion criteria for the study disclosed in Example 1.

[0288] The following inclusion and exclusion criteria were used for the study.

[0289] 1. Patients had a confirmed diagnosis of systemic amyloidosis (SA), based on either a histologic confirmation that a biopsy contained deposits of apple-green birefringent, Congophilic material or genetic screening and presence of amyloid-related pathology, or amyloid- specific imaging study. Additionally, the type of amyloidosis (AL, ATTR, ALECT2, or other) was characterized.

[0290] 2. Patients enrolled in Part 1 (n = 3) had widespread AL amyloidosis, defined as biopsy proven or clinically detectable involvement, of at least two organs (excluding the peripheral nervous system).

[0291] 3. All patients in Parts 1 and 2 were 18 years of age or older. There were no gender or racial restrictions.

[0292] 4. Women of childbearing potential (those who had not been surgically sterilized, were not postmenopausal [typically understood to mean last menstrual period >2 y ago without pharmaceutical intervention], and women who were fertile) had to test negative for pregnancy in a laboratory test administered by the site physician.

[0293] 5. Patients who had or were currently receiving therapy or other drug based anti-amyloid regimens could be included on study (Parts 1 and 2).

[0294] 6. Patients provided signed, written, informed consent and complied with eligibility requirements, scheduled visits, and follow-up studies. [0295] 7. Due to annual dosimetry limitations, patients who had participated in another nuclear medicine amyloid imaging clinical trial protocol could be included in this study no earlier than 12 months after the previous radiotracer injection.

[0296] Prior to participation in Part 3 (n = 2) of the trial, the following inclusion criteria were required:

[0297] 1. Patients had a well-defined germline mutation of the transthyretin (TTR) gene rendering them at risk for amyloidosis and were free of clinical evidence of SA.

[0298] 2. All patients in Part 3 were >50 years of age. There were no gender or racial restrictions.

[0299] 3. Women of childbearing potential (those who had not been surgically sterilized, were not postmenopausal [typically understood to mean last menstrual period >2 y ago without pharmaceutical intervention], and women who were fertile) had to test negative for pregnancy in a laboratory test administered by the site physician.

[0300] 4. Subjects provided signed, written, informed consent and complied with eligibility requirements, scheduled visits, and follow-up studies.

[0301] 5. Due to annual dosimetry limitations, subjects who had participated in another nuclear medicine amyloid imaging clinical trial protocol could be included in this study no earlier than 12 months after the previous radiotracer injection.

[0302] Prior to participation Part 4 of the trial (n = 5), the following inclusion criteria were required:

[0303] 1. Healthy Control Subjects (HC) were generally healthy adults, either male or female, and did not have a diagnosis of amyloidosis, did not have a first- or second-degree relative (parent, sibling, child, aunt, uncle, niece, nephew) with confirmed or suspected familial amyloidosis, and did not have diabetes mellitus (type 2).

[0304] 2. All Part 4 subjects were > 30 years of age or older.

[0305] 3. Women of childbearing potential (those who had not been surgically sterilized, were not postmenopausal [typically understood to mean last menstrual period >2 y ago without pharmaceutical intervention], and women who were fertile) had to test negative for pregnancy in a laboratory test administered by the site physician.

[0306] 4. Patients provided signed, written, informed consent and complied with eligibility requirements, scheduled visits, and follow-up studies. [0307] 5. Due to annual dosimetry limitations, patients who had participated in another nuclear medicine imaging clinical trial protocol could be included in this study no earlier than 12 months after the previous radiotracer injection.

[0308] Prior to participation in Part 5 (n= 1 ) of the trial, the following inclusion criteria were required:

[0309] 1. Patients had successfully completed participation in Part 2 or Part 3 of this trial with CT/PET images confirming the presence of abnormal amyloid deposits in thoracoabdominal organs.

[0310] 2. Patients had received a 2 mCi dose of 124I-p5+14 during Part 2 or 3 of this trial with visual evidence of uptake of radiotracer in abdominothoracic organs associated with amyloid.

[0311] 3. The repeat exposure to the study agent occurred at least 6 months after the first exposure.

[0312] 4. Patients submitted a serum specimen for exploratory evaluation of the presence of p5+14 peptide-reactive antibodies, with results reviewed by the Principal Investigator prior to a second exposure to the study agent.

[0313] 5. The patient met all of the Inclusion criteria for participation in Part 2 or Part

3, including the signing of an informed consent for Part 5.

[0314] The following criteria excluded candidates from participation in the trial, Parts 1 and 2:

[0315] 1. Those with significant co-morbidity (e.g., Eastern Cooperative Oncology

Group [ECOG] score of 3 or greater), uncontrolled infection, or other serious illness.

[0316] 2. Patients with a sustained SpO2 of < 92% as noted in the medical record.

[0317] 3. Patients that required renal dialysis.

[0318] 4. Women who were of childbearing potential (those who had not been surgically sterilized, were not postmenopausal [typically understood to mean last menstrual period >2 y ago without pharmaceutical intervention], and women who were fertile) who tested positive for pregnancy in a laboratory test administered by the site physician, were pregnant, or were nursing

[0319] 5. Patients who had received any amyloidophilic radiotracer as part of a research clinical trial (not standard of care) within the past 12 months. [0320] 6. Patients with exposure to heparin, or heparin-based medications, within 7 days prior to the imaging study.

[0321] 7. Patients who had a known allergy to acetaminophen or iOS AT iodine treatment.

[0322] The following criteria excluded candidates from participation in Part 3 of the trial:

[0323] 1. Those with significant co-morbidity (e.g., Eastern Cooperative Oncology

[0324] 2. Subjects with a sustained SpO2 of < 92% as noted in the medical record.

[0325] 3. Women who were of childbearing potential (those who had not been surgically sterilized, were not postmenopausal [typically understood to mean last menstrual period >2 y ago without pharmaceutical intervention], and women who were fertile) who tested positive for pregnancy in a laboratory test administered by the site physician, were pregnant, or were nursing.

[0326] 4. Subjects who had clinical evidence of amyloidosis based on standard clinical criteria.

[0327] 5. Subjects with polyneuropathy of unknown origin.

[0328] 6. Subjects who had received any amyloidophilic radiotracer as part of a research clinical trial (not standard of care) within the past 12 months.

[0329] 7. Subjects with exposure to heparin, or heparin-based medications, within 7 days prior to the imaging study.

[0330] 8. Subjects who had a known allergy to acetaminophen or iOS AT iodine treatment.

[0331] 9. Subjects with clinical signs of SA based on routine investigation of serum and urine biomarkers, radiographic or nuclear imaging studies, or peripheral nerve evaluations.

[0332] The following criteria excluded subjects from participation in Part 4:

[0333] 1. Those with significant co-morbidity (e.g., Eastern Cooperative Oncology

Group [ECOG] score of 2 (Restricted in physically strenuous activity but ambulatory and able to carry out work of a light or sedentary nature, e.g., light housework, office work) or greater), uncontrolled infection, or other serious illness.

[0334] 2. Individuals with a sustained SpO2 of < 92% as noted in the medical record. [0335] 3. Women who were of childbearing potential (those who had not been surgically sterilized, were not postmenopausal [typically understood to mean last menstrual period >2 y ago without pharmaceutical intervention], and women who were fertile) who tested positive for pregnancy in a laboratory test administered by the site physician, were pregnant, or were nursing.

[0336] 4. Subjects who had received any amyloidophilic radiotracer as part of a research clinical trial (not standard of care) within the past 12 months.

[0337] 5. Subjects with exposure to heparin, or heparin-based medications, within 30 days prior to the imaging study.

[0338] 6. Subjects who had a known allergy to acetaminophen or iOSAT iodine treatment.

[0339] 7. Subjects with a diagnosis of Type 2 diabetes mellitus or who were taking medication for management of Type 2 diabetes mellitus.

[0340] 8. Active infection requiring systemic antiviral or antimicrobial therapy that would not be completed prior to Study Day 1.

[0341] 9. Known history of or positive test for human immunodeficiency virus

(HIV), hepatitis C or chronic hepatitis.

[0342] 10. Uncontrolled hypertension (BP > 160/100 mm Hg).

[0343] 11. Smoked >20 cigarettes a day.

[0344] 12. A diagnosis of heart failure with preserved ejection fraction.

[0345] 13. Had any other conditions, which, in the opinion of the Investigator would make the subject unsuitable for inclusion, or could interfere with the subject participating in or completing the study

[0346] The following criteria excluded subjects from participation in Part 5:

[0347] 1. Any patient who experienced a clinically significant adverse event related to prior exposure to the study agent.

[0348] 2. Any subject who met any of the Exclusion Criteria for Part 2 or Part 3 (as applicable). Example 3: Cardiac Amyloid Quantification Using ¹²⁴I-P5+14 (¹²⁴I-p5+14) versus 18F- Florbetapir: A Pilot PET/CT Study

[0349] This example describes a pilot study to quantify myocardial ¹²⁴I-p5+14 uptake and to compare its diagnostic value to ¹⁸F-florbetapir in participants with amyloid cardiomyopathy (CMP) and controls. The primary aims of this pilot study were (1) to quantify ¹²⁴I-p5+14 cardiac uptake in participants with amyloid CMP and controls, (2) to compare the diagnostic value of ¹²⁴I-p5+14 and ¹⁸F-florbetapir in AL-CMP and ATTRwt-CMP, and (3) to measure correlations between ¹²⁴I-p5+14 myocardial uptake and metrics of cardiac structure and function, serum biomarkers, functional status and quality of life as markers for amyloid burden.

Methods

PARTICIPANT INCLUSION

[0350] The study was approved by the Mass General Brigham Human Research Committee, and each participant provided written informed consent (protocol number 2021P000085). The use of ¹²⁴I-p5+14 was approved by the Food and Drug Administration under an Investigational New Drug application (155808). Between July 2021 and June 2023, 46 participants were included: 12 with AL-CMP, 12 with ATTRwt-CMP, 2 with hereditary amyloid CMP (1 variant ATTR [ATTRv] with Thr60Ala [p.T80A], 1 apolipoprotein A-IV amyloidosis [AApoAIV]), and 12 control participants without amyloidosis. Additionally, 8 controls participants from previous studies with ¹⁸F-florbetapir PET/CT were included (Dorbala S, Vangala D, Semer J, et al. Eur J Nucl Med Mol Imaging. 2014;41:1652-1662). One AL-CMP participant was excluded due to an acquisition error during ¹²⁴Lp5+14 imaging. Hereditary amyloidosis participants were not included in statistical analyses due to small numbers (N=2), but presented visually for comparison. AL-CMP was diagnosed using standard criteria for systemic AL amyloidosis, including biopsy with confirmation of amyloid type by immunohistochemistry or mass spectrometry, and proof of cardiac involvement by imaging or endomyocardial biopsy. ATTRwt amyloidosis was diagnosed by a grade 2/3 cardiac "^mTc- pyrophosphate (^99mTc-PYP) SPECT/CT scan and exclusion of AL amyloidosis by serum free light chain assay and serum and urine immunofixation electrophoresis, or by endomyocardial biopsy with immunohistochemistry or mass spectrometry. Hereditary amyloid CMP was diagnosed by biopsy with immunohistochemistry or mass spectrometry, the finding of a variant TTR by genetic sequencing if appropriate, and proof of cardiac involvement by imaging or endomyocardial biopsy.

PET/CT ACQUISITION

[0351] Participants with amyloid CMP underwent molecular imaging of amyloidosis using ¹²⁴I-p5+14 and ¹⁸F-florbetapir PET/CT (except one AL-CMP participant in whom only ¹²⁴I-p5+14 PET/CT could be performed). Controls underwent one PET/CT: 12 with ¹²⁴I-p5+14 and 8 with ¹⁸F-florbetapir. Imaging was performed using a Discovery MI PET/CT scanner (GE Healthcare, Chicago, IL, USA) with CT scout for patient positioning and low-dose chest CT scan for attenuation correction and image fusion. Acquisition and quantification methods were specific to each radiotracer, given differences in radiotracer characteristics. ¹²⁴I-p5+14 was injected intravenously over 5 minutes. Cardiac PET acquisition was performed for 30 minutes in static mode only, 5 hours post-injection to allow for clearance of blood pool activity, based on previous data on radiotracer kinetics. The median net injected activity, limited by concerns about exposure to participants and staff, was 1.00 mCi (interquartile range [IQR] 0.94-1.07), with a median effective dose of 9.01 mSv (IQR 8.55-9.47, based on 0.23 mSv/MBq, including 0.5 mSv for the low-dose CT scan). We protected the thyroid gland using potassium iodide 130 mg for 7 days, starting 1 day before radiotracer injection. 18F-florbetapir was injected as a bolus 1 minute after starting the PET acquisition in list mode. Static images of the heart were reconstructed using data from 4 to 30 minutes after radiotracer injection, based on a previous publication. The median net injected activity was 7.15 mCi (IQR 6.33-8.40), with a median effective dose of 5.58 mSv (IQR 4.99-6.46, including 0.5 mSv for low-dose CT scan). The ¹²⁴I-p5+14 scan was performed a median of 1.5 days (IQR 1-4.5, range 1-12 days) after the ¹⁸F-florbetapir scan.

PET/CT QUANTIFICATION

[0352] Myocardial uptake was measured volumetrically on static images using PMOD software (PMOD Technologies LLC, Zurich, Switzerland). Because manual tracing of the myocardial contour on each slice lacks reproducibility and is inaccurate in controls, we used automatic iso-contouring in PMOD to exclude ventricular blood pool and delineate the myocardium in a reproducible manner. First, volumes of interest (VOI) were manually traced on PET emission images guided by fused CT images to define the left ventricular (LV) and right ventricular (RV) contours including cavity blood pool, and attributing the interventricular septum to LV tracings. Given differences in radiotracer kinetics and target-to-background ratio, specific iso-contouring thresholds were chosen for each radiotracer. Blood pool activity concentration was measured in a 10-mm-diameter left atrial (LA) spherical VOL For ¹⁸E- florbetapir, we used a threshold of 2 x mean blood pool activity concentration, as in our previous study. For ¹²⁴I-p5+14, we used a threshold of mean + 2 standard deviations of blood pool activity concentration, which better delineated myocardial volumes, particularly in mild cases (FIG. 6).

[0353] To perform automatic iso-contouring on ¹²⁴I-evuzamitide PET images, we first traced volumes of interest (VOI) manually on fused PET/CT images to define the global left ventricular and right ventricular (LV and RV) contours. Then, we measured blood pool activity concentration in a 10 mm diameter left atrial (LA) spherical VOI. Next, we used the isocontouring function of PMOD software with a threshold at mean + 2 standard deviations (SD) of the LA blood pool activity concentration, which appropriately delineated the myocardial volume in cases with various levels of uptake. By contrast, in the last column, a threshold at 2 x mean LA blood pool activity concentration, as used for ¹⁸E-florbetapir, would ignore a relevant fraction of the myocardial volume. This is why we used a specific threshold for ¹²⁴I-evuzamitide (LA+2SD).

[0354] Our primary LV and RV uptake metric was percent injected dose (%ID), calculated as VOI mean activity concentration x VOI volume / injected activity.26 This metric adjusts for injected activity, but not for body weight, the latter unnecessary for a radiotracer accumulating in the heart and specific organs, not in the whole body. We additionally analyzed standardized uptake (SUVmean, SUVmax) as mean or maximal VOI activity concentration / (injected activity / body weight), cardiac amyloid activity (CAA) as VOI SUVmean x VOI volume, and target-to background ratio (TBR) as VOI mean activity concentration / blood pool mean activity concentration (identical to a SUVratio, where corrections for injected activity and weight in SUV cancel out in the ratio). Thresholds for abnormally high uptake values were defined in receiver operating characteristic (ROC) analysis by maximization of Youden’s index (sensitivity + specificity - 1) to identify cut-offs with optimal sensitivity and specificity to classify CMP cases vs. controls, giving equal weight to false positive and false negative cases.

STRUCTURAL AND EUNCTIONAL MARKERS OE AMYLOID BURDEN [0355] Reports and, when available, images from clinically performed echocardiograms (N=23), cardiac MRI (N=13), and 99mTc-PYP SPECT (N=l l) within one year of PET/CT were retrieved. Older 99mTc-PYP SPECT results were included if Grade 3, as no further change was expected. Median time differences to PET/CT were 1.7 (IQR 0.7-4.1) months for echocardiogram, 2.7 (IQR 0.7-5.0) months for MRI, and 4.5 (IQR 2.5-13.8) months for SPECT. Interventricular septum thickness, LV mass index, ejection fraction, myocardial contraction fraction (MCF = stroke volume / myocardial volume), global longitudinal strain (GLS), late gadolinium enhancement, ECV, and 99mTc-PYP grade were evaluated.

LABORATORY TESTS, FUNCTIONAL STATUS, AND QUALITY OF LIFE

[0356] In all participants, serum levels of troponin T, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and creatinine were measured. Functional status was assessed using the New York Heart Association class (NYHA) and the 6-minute walk test distance. Quality of life was measured using the Minnesota living with heart failure questionnaire (MLWHFQ, 21 questions, total score 0-105 points, higher values indicating worse symptoms), the Kansas City Cardiomyopathy Questionnaire (KCCQ, 23 questions, overall score 0-100 points, higher values indicating less symptoms), and the 36-Item Short Form Survey (SF-36, 36 questions, transformed T- scores for normalized population 0-100, higher values indicating better quality of life).

STATISTICAL ANALYSIS

[0357] Continuous variables were presented as median with IQR and compared using Kruskal-Wallis test, followed by Dunn’s test for pairwise testing. We included an adjustment for multiple testing using the Benjamini-Hochberg procedure. Categorical variables were displayed as frequency with percentage and assessed using Fisher’s exact test. Paired variables were compared using Wilcoxon signed-rank test or McNemar’s test, as appropriate. Correlations were quantified using Spearman’s p with 95% CI using the Fieller correction. We presented two-sided p-values and considered them as statistically significant if <0.05. Data were analyzed using R version 4.3.0 (R Core Team. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria), using the packages tidyverse, DescTools, gtsummary, rstatix, pROC, and correlation.d Results

PATIENT CHARACTERISTICS

[0358] In amyloid CMP participants (N=24), median age was 74 years (IQR 69-78) and 22 were male (92%). ATTRwt-CMP participants (N=12) were older, had a lower heart rate and worse cardiac metrics, such as LV mass index, ejection fraction, and GLS, than AL-CMP participants (N=12). But other demographics, clinical characteristics, quality of life, functional status, and biomarkers were similar (Table 9). At study inclusion, 10 AL-CMP participants were in hematological remission after plasma cell-directed therapy (83%) and 2 were undergoing therapy and not in remission (17%), while 10 ATTRwt-CMP participants received tafamidis (83%). In controls (N=20), median age was 62 years (IQR 58-67) and 13 were male (65%).

Table 9: Participant Characteristics

Continuous and ordinal variables are presented as median (interquartile range), with p-values from Kruskal-Wallis test for 3 groups or Wilcoxon rank-sum test for 2 groups. For MLWHFQ, KCCQ, and SF-36, the data range is also presented. Categorical variables are presented as frequencies (percentages), with p-values from Fisher’s exact test.

* Only demographical data were available for the ¹⁸F-florbetapir control cohort.

BP: Blood pressure. ECV: Extracellular volume. eGFR: Estimated glomerular filtration rate. GLS: Global longitudinal strain. KCCQ: Kansas City cardiomyopathy questionnaire. LGE: Late gadolinium enhancement. MCF: Myocardial contraction fraction (stroke volume / myocardial volume). MLWHFQ: Minnesota living with heart failure questionnaire. MRI: Magnetic resonance imaging. NT-proBNP: N- terminal pro-B-type natriuretic peptide. NYHA: New York Heart Association. SF-36: 36-ltem Short

Form Survey.^99mTc-PYP SPECT: 99mTc-pyrophosphate single-photon emission computed tomography. _

¹²⁴I-P5+14 PET/CT LV AND RV MYOCARDIAL UPTAKE

[0359] Radiotracer injection was well tolerated in all participants and no adverse effects were noted. Substantial cardiac uptake of ¹²⁴I-p5+14 was observed in all amyloid CMP participants regardless of amyloid type, while all control participants had no visual cardiac uptake. Moreover, in a participant with equivocal Grade 1 "^mTc-PYP SPECT/CT, ¹²⁴I-p5+14 PET/CT demonstrated definite myocardial uptake, confirmed by endomyocardial biopsy showing TTR amyloid deposits (FIG.7).¹²⁴I-p5+14 LV %ID differed across groups (overall p<0.001): AL-i-CMP median 1.48 (IQR 1.12-1.89), ATTRwt-CMP 2.12 (1.66-2.47), and controls 0.00 (0.00-0.01, Table 8). Several uptake metrics tended to be higher in ATTRwt-CMP than in AL-CMP, particularly LV SUVmean and RV metrics (FIG.8, Table 10). Based on Youden’s index, high LV %ID, LV CAA, and LV TBR perfectly discriminated amyloid CMP cases from controls, while LV SUVmean, SUVmax and RV metrics showed some overlap (FIG.8, Table 10). Indeed, a few control participants presented heterogeneous background activity with small spots of activity concentration above the automatic iso-contouring threshold based on blood pool. This led to SUVmean in the range of amyloid CMP, but it was not visually suggestive of amyloid deposition. By contrast, %ID and CAA were close to zero in control participants, because these metrics included VOI volume, and therefore better differentiated amyloid deposits in CMP cases from heterogeneous background activity in control participants.

Table 10: ¹²⁴I-P5+14 and ¹⁸F-Florbetapir Myocardial Uptake Metrics

Variable AL-CMP ATTRwt-CMP Controls p-value

¹²⁴l-p5+14 (N = 12) (N = 12) (N = 12)

Left ve

%ID 8 (1.12-1.89) 2.12 (1.66-2.47) 0.00 (0.00-0.01) <0.001

SUVm 7(3.20-4.49) 4.78(4.25-5.47) 3.04(2.97-3.46) 0.004

SUVm 8(5.16-7.20) 8.03(6.84-8.82) 3.48(3.21 -3.97) <0.001

CAA 6(856-1424) 1908(1340-2046) 2(1 -8) <0.001

TBR 8(1.75-2.16) 1.89(1.77-2.06) 1.20(1.17-1.27) <0.001

Volum 0 (246 - 350) 375 (334 - 426) 1 (0-3) <0.001

High

12(100%) 12(100%) 0(0%) <0.001

Measurement procedures and calculations for all metrics are explained in the Methods. High %ID was defined using Youden’s index, and thresholds are indicated. Continuous variables are presented as median (interquartile range), with p-values from Kruskal-Wallis test. Categorical variables are presented as frequencies (percentages), with p-values from Fisher’s exact test. Marked ¹⁸F-florbetapir values were significantly (p<0.05) higher (*) or lower (f) than their ¹²⁴l-p5+14 counterparts by Wilcoxon signed-rank test or McNemar’s test for AL-CMP and ATTRwt-CMP participants (paired), by Wilcoxon rank-sum test or Fisher’s exact test for control participants (unpaired). The percentage of high %ID in AL-CMP and ATTRwt-CMP corresponds to sensitivity, and 100 - percentage of high %ID in controls corresponds to specificity. _

¹⁸F-FLORBETAPIR PET/CT LV AND RV MYOCARDIAL UPTAKE

[0360] In the same amyloid CMP participants (except one AL-CMP participant without ¹⁸F-florbetapir PET/CT), and in different control participants, we found similar results with ¹⁸F-florbetapir as with ¹²⁴I-p5+14 (FIG. 9, Table 10). ¹⁸F-florbetapir LV %ID also differed across groups (overall p<0.001): AL-i-CMP median 1.03 (IQR 0.78-2.03), ATTRwt-CMP 1.10 (0.89-1.44), and controls 0.04 (0.00-0.29). LV myocardial uptake metrics did not differ between AL-CMP and ATTRwt-CMP participants, but the range of values was higher with AL-CMP. High LV %ID and LV CAA perfectly discriminated amyloid CMP cases from controls, while LV SUVmean, LV TBR, and RV metrics showed some overlap.

MYOCARDIAL RADIOTRACER UPTAKE METRICS WITH ¹²⁴LP5+14 VS. ¹⁸F- FLORBETAPIR

[0361] When comparing LV myocardial radiotracer uptake within the same participants, LV and RV %ID, SUVmean, SUVmax, and CAA were similar with ¹²⁴Lp5+14 and ¹⁸F-florbetapir in AL-CMP, but higher with ¹²⁴Lp5+14 in ATTRwt-CMP (all p<0.002, FIG.10, Table 10). LV and RV TBR were higher with ¹⁸F-florbetapir than with 124Lp5+14 in AL-CMP and ATTRwt-CMP (all p<0.002), reflecting the differing blood and tissue kinetics of the two tracers.

[0362] Correlation Between ¹²⁴LP5+14 Uptake and Direct and Indirect Markers of Amyloid Burden, Functional Status and Quality of Life

[0363] In the entire cohort, we found moderate correlations between ¹²⁴Lp5+14 LV %ID and NYHA class (p=0.47), MLWHFQ total score (p=0.59), KCCQ overall score (p=-0.62), SF-36 physical T-score (p=-0.50), SF-36 mental T-score (p=-0.41), as well as strong correlations with troponin T (p=0.73) and NT-proBNP (p=0.72; Table 9). Moreover, in the AL-CMP and ATTRwt-CMP participants, we found moderate to strong correlations between ¹²⁴Lp5+14 LV %ID and ¹⁸F-florbetapir LV %ID (p=0.50), interventricular septum thickness (echocardiogram p=078, MRI p=0.58), LV mass index (echocardiogram p=0.70, MRI p=0.82), LV MCF (echocardiogram p=-0.66, MRI p=-0.62), LV GLS (p=0.54), and LV ECV (p=0.51).

Table 11: Correlation Between ¹²⁴I-P5+14 Uptake and Direct and Indirect Markers of Amyloid Burden, Functional Status and Quality of Life

Correlations between ¹²⁴l-p5+14 LV %ID and quality of life, functional status and laboratory tests were assessed in participants undergoing ¹²⁴l-p5+14 PET/CT (12 AL- CMP, 12 ATTRwt-CMP and 12 controls). Correlations with echocardiogram, cardiac MRI and radionuclide imaging were evaluated in participants with amyloid cardiomyopathy and available imaging metrics. Results are presented as Spearman’s p (95% confidence interval).

Discussion

[0364] This pilot study quantified myocardial uptake of ¹²⁴I-p5+14, a novel pan- amyloid-binding radiotracer, in participants with amyloid CMP, compared its diagnostic value to that of 18F-florbetapir, and measured correlations between ¹²⁴I-p5+14 myocardial uptake and markers of amyloid burden in amyloid CMP. Visual interpretation of ¹²⁴I-p5+14 PET/CT images identified cardiac amyloidosis in all participants with AL, ATTRwt, ATTRv, or AApoAIV CMP. All ¹²⁴I-p5+14 LV and RV myocardial quantitative uptake metrics were significantly higher in participants with either AL-CMP or ATTRwt-CMP than in control participants. Importantly, ¹²⁴I-p5+14 LV %ID, CAA, and TBR perfectly discriminated all cases of known AL-CMP and ATTRwt-CMP from controls. Similar results were observed with 18L-florbetapir in the same amyloid CMP participants, except for TBR, supporting the validity of ¹²⁴I-p5+14 findings. Thus, LV %ID and CAA were the most accurate metrics to identify amyloid CMP with both radiotracers. When comparing radiotracers, ¹²⁴I-p5+14 consistently showed higher myocardial values in ATTRwt-CMP, except for TBR. Furthermore, among AL-CMP and ATTRwt-CMP participants, ¹²⁴I-p5+14 LV %ID was moderately to strongly correlated with indirect metrics of amyloid burden from echocardiogram and MRI (interventricular septum thickness, LV mass index, MCF, GLS, ECV), suggesting valid amyloid burden quantitation. Moreover, ¹²⁴Lp5+14 LV %ID was moderately correlated with 18F-florbetapir LV %ID, suggesting different binding sites, different binding affinities and/or quantification of different components of amyloid deposits. Indeed, ¹²⁴Lp5+14 was specifically designed to bind to electronegative surfaces of glycosaminoglycans and amyloid fibrils, 19 while 18F-florbetapir is a stilbene, similar in structure to thioflavin T, which is known to bind to the P-sheet surface along channels formed by cross-strand ladders within amyloid fibrils.27 Correlation between ¹²⁴L p5+14 LV %ID and ECV was also moderate, which may be due to ECV measuring fibrosis, inflammation, and/or edema in addition to amyloid deposits.6 Correlations with functional status and quality of life were moderate, and correlations with cardiac biomarkers were strong, which further supports the validity of cardiac amyloid quantitation with ¹²⁴Lp5+14 PET/CT. Finally, ¹²⁴Lp5+14 injection was well tolerated in all participants, and no adverse effects were noted.

[0365] ¹²⁴Lp5+14 is an innovative radiotracer based on the synthetic polypeptide p5+14, which was developed to bind to electronegative surfaces of glycosaminoglycans and amyloid fibrils in all types of amyloid deposits. This polypeptide was successfully tested in diverse radiotracers in a murine model of serum amyloid A amyloidosis, and in humans with multiple types of systemic amyloidosis. The present study is novel in its ability to systematically evaluate myocardial uptake with ¹²⁴Lp5+14 in a cohort of participants with amyloid CMP from multiple precursor proteins, and is the first to compare it to ¹⁸F-florbetapir. Our findings support the use of ¹²⁴Lp5+14 PET/CT imaging to accurately and safely diagnose AL-CMP and ATTRwt- CMP, and to contribute to identify hereditary amyloid CMP. These results suggest that this panamyloid binding radiotracer has the potential to reduce the need for endomyocardial biopsy to diagnose cardiac amyloidosis, limiting biopsy to patients with positive scans for whom amyloid type confirmation is needed. Our results also suggested that ¹²⁴Lp5+14 can quantify cardiac amyloid burden. Indeed, LV ¹²⁴Lp5+14 uptake was correlated with LV structural and functional measures of amyloid burden, as well as with cardiac biomarkers and heart-failure-related quality of life. Imaging with ¹²⁴I-p5+14 before therapy could identify the presence and quantify the amount of amyloid in the heart and other organs, specifically predicting potential main effects and organ- specific side effects, while imaging after therapy could measure organ response. Although ECV may be an alternative approach to quantify amyloid burden in the heart, it is not specific for amyloidosis and may also represent inflammation or fibrosis, processes that may be triggered by macrophage-mediated amyloid removal. Therefore, targeted imaging of myocardial amyloid using a specific molecular radiotracer may offer relevant advantages over other methods.

[0366] Recently, P-amyloid-targeting PET radiotracers, (¹¹C-Pittsburgh-B-compound, ¹⁸F-florbetapir, ¹⁸F-florbetaben, and ¹⁸F-flutemetamol) have emerged as useful tools to evaluate AL-CMP. However, these radiotracers have a limited ability to detect ATTR-CMP, particularly ¹⁸F-florbetapir and ¹⁸F-florbetaben. Non-invasive diagnosis of ATTR-CMP is usually based on SPECT bone-avid radiotracers ("^mTc-pyrophosphate [^99mTc-PYP], "^mTc-3-diphosphono-l,2- propanodicarboxylic acid [^99mTc-DPD], "^mTc-hydroxy methylene diphosphonate [^99mTc- HMDP]). Grade 2/3 uptake of these radiotracers was reported as nearly 100% specific, but only 74% sensitive for ATTR-CMP. Indeed, bone-avid SPECT radiotracers may lack the sensitivity to detect early disease in ATTR-CMP, and are unreliable to diagnose AL-CMP, some forms of ATTRv-CMP, and other rare forms of amyloid CMP. Furthermore, these data originate from high-volume centers assessing selected patients with advanced disease or high pre-test probability, and may therefore overestimate the diagnostic performance of SPECT in nonspecialized centers. Moreover, serial quantitative testing with bone-avid radiotracers is limited by the relatively low sensitivity of SPECT compared to PET, and by the early stage of development of quantitative SPECT methods. Importantly, the mechanism of myocardial uptake of bone-avid radiotracers is not known, compromising the interpretation of changes following therapy. By contrast, ¹²⁴I-p5+14, a PET pan-amyloid-binding radiotracer, might offer higher quantitative accuracy than SPECT bone-avid radiotracers and may be more sensitive that P- amyloid- specific PET radiotracers for ATTR-CMP. Notably, in the present study, we found significantly higher myocardial uptake values with ¹²⁴I-p5+14 than with ¹⁸F-florbetapir among ATTRwt-CMP participants. These participants also tended to show higher ¹²⁴I-p5+14 uptake than AL participants, while uptake was more similar across amyloid types with 18F-florbetapir. In parallel, ATTRwt-CMP participants had worse structural and functional metrics on echocardiogram and cardiac MRI than AL-CMP participants, such as LV mass index and GLPS. Thus, the higher myocardial uptake values with ¹²⁴I-p5+14 in ATTRwt-CMP might better reflect the severity of the cardiomyopathy and might be more sensitive to diagnose early disease than ¹⁸F-florbetapir. Techniques that provide specific and quantitative estimates of both cardiac AL and ATTR amyloid burden are much needed to evaluate organ response to amyloid-depleting therapies, and ¹²⁴I-p5+14 may fill that gap.

[0367] In conclusion, ¹²⁴I-p5+14 PET/CT imaging is a promising novel radiotracer able to accurately detect cardiac amyloid deposits of multiple types, to discriminate between presence and absence of cardiac amyloidosis, and to quantify cardiac amyloid burden. In ATTRwt-CMP, amyloid quantification with ¹²⁴I-p5+14 might be more accurate than with 18F- florbetapir. Larger, multicenter studies are needed to validate these findings and to further evaluate the clinical utility of ¹²⁴I-p5+14 PET/CT imaging for early diagnosis and therapeutic monitoring of cardiac amyloidosis.

Example 4: Monitoring of Amyloid progression and regression by PET/CT Imaging of ¹²⁴I- p5+14

[0368] This example describes monitoring of Amyloid progression and regression through semi-quantitative analysis of PET/CT imaging of a novel amyloid-reactive peptide, designated p5+14, labeled with iodine-124 (¹²⁴I-p5+14), in patients with diverse types of systemic amyloidosis. Methods

[0369] This was the multi-part, open-label study to assess the safety, dosimetry and biodistribution of ¹²⁴I-p5+14 peptide in patients with systemic amyloidosis of any type; pre- symptomatic subjects carrying a germline TTR mutation; and healthy subjects described in Example 1. In this example, 9 patients with AL and 10 patients with ATTR received repeat PET/CT imaging to visualize and quantify changes in organ specific uptake of ¹²⁴I-p5+14 peptide from a baseline. The imaging protocol is described in Example 1.

[0370] Uptake of ¹²⁴I-p5+14 peptide in the organs was quantified by measuring the standard uptake value ratio (SUVR) and the amount of radioactivity per unit volume (Bq/cc) scaled by the blood pool radioactivity. Correlations between SUVR and serum NTproBNP, left ventricular (LV) wall and interventricular septal (IVS) thickness, and global longitudinal strain were calculated. Results

[0371] Change in uptake of ¹²⁴I-p5+14 peptide in the organs as measured by standard uptake value ratio (SUVR) and Serum NTproBNP for the 9 patients with AL amyloidosis is shown in FIG 11A. For the AL patient population, 1/9 (11%) showed reduced SUVRmean to near normal, 7/9 (78%) showed stable cardiac SUVRmean , 1/9 (11%) showed increased cardiac SUVRmean with no change in NTproBNP, and 8/9 (89%) showed stable NTproBNP with 1/9 (11%) showing increased NTproBNP.

[0372] Change in uptake of ¹²⁴Lp5+14 peptide in the organs as measured by standard uptake value ratio (SUVR) and Serum NTproBNP for the 9 patients with ATTR amyloidosis is shown in FIG 11B. In the ATTR patient population 2/10 (20%) showed a greater than 20% reduction in cardiac SUVRmean, 7/10 (70%) showed stable SUVRmean. 1/10 (10%) showed an increase in cardiac SUVRmean with no change in NTproBNP and 9/10 (90%) showed stable NTproBNP levels with 1/10 (10%) showing a decrease in NTproBNP.

[0373] Across all patients, the change in NTproBNP between imaging time points correlated with change in cardiac uptake in ¹²⁴Lp5+14 (Table 12, FIG. 12). No correlation between changes in serum NTproBNP and change in cardiac uptake of ¹²⁴Lp5+14 was detected in either AL patients or ATTR patients when each group was evaluated separately.

Table 12: Correlation between changes in serum NTproBNP and change in cardiac uptake of 124I-p5+14

[0374] In AL patients a correlation was detected between SUVR and LV wall and GLS but not with IVS (FIG. 13A-C) In ATTR patients a correlation was detected between SUVR and LV wall and IVS but not GLS (FIG. 13 D-F). For all patients, a correlation was detected between SUVR and LV wall, IVS, and GLS (FIG. 13G-I). Discussion

[0375] This example shows semi-quantitative analysis of ¹²⁴I-p5+14 uptake using PET/CT imaging allows for monitoring of amyloid progression and regression as well as a way to study the relationships between amyloid, amyloidosis, organ function, and patient outcomes.

Example 5: Early Cardiac Amyloid Detection by PET/CT Imaging of ¹²⁴I-p5+14

[0376] This study is a phase 3 evaluation of the efficacy of ¹²⁴I-p5+14 for diagnosing cardiac amyloidosis. The primary objective is to evaluate the sensitivity and specificity of PET/CT imaging with ¹²⁴I-p5+14 for the diagnosis of cardiac amyloidosis based on visual scan interpretation.

[0377] The secondary objective is to evaluate the safety of a single intravenous administration of ¹²⁴I-p5+14 by tracking incidence of treatment-emergent Adverse Events (AEs) from Day 1 to Day 30 and changes from Baseline in clinical laboratory values.

[0378] The exploratory objectives are: 1) to evaluate the efficacy of ¹²⁴I-p5+14 for diagnosing cardiac ATTR amyloidosis, 2) to evaluate the efficacy of ¹²⁴I-p5+14 for diagnosing cardiac AL amyloidosis, 3) to evaluate the efficacy of ¹²⁴I-p5+14 for distinguishing AL versus ATTR cardiac amyloidosis, 4) to evaluate the correlation between quantitative cardiac uptake of ¹²⁴I-p5+14 and amyloid content in endomyocardial biopsies, cardiac biomarkers, clinical stage, participant-reported heart failure health status, and standard measures of structure and function using imaging, 5) to evaluate participant preference for biopsy or multimodal imaging versus ¹²⁴I-p5+14 PET/CT imaging.

Inclusion and Exclusion Criteria

[0379] The following inclusion criteria is used for this study.

[0380] 1) Understands the study procedures and can give signed informed consent (as specified in Section 10.1.3), which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol.

[0381] 2) Male or female >18 years of age.

[0382] 3) Is suspected of having cardiac amyloidosis and is willing to undergo a diagnostic evaluation for cardiac amyloidosis (e.g., echocardiography, CMR, bone avid tracer cardiac SPECT, extracardiac or endomyocardial biopsy, etc.). Participants can be enrolled before or during their diagnostic evaluation for cardiac amyloidosis.

[0383] 4) Able to undergo PET/CT imaging as part of the study, including ability to lie supine for approximately 1 hour.

[0384] 5) For women of childbearing potential: agreement to remain abstinent

(refrain from heterosexual intercourse) or use contraceptive methods that result in a failure rate of < 1% per year during the treatment period and for at least 30 days after administration of ¹²⁴I- p5+14. a. A woman is considered of childbearing potential if she is postmenarchal, has not reached a postmenopausal state (>12 months of amenorrhea with no identified cause other than menopause), and has not undergone surgical sterilization (removal of ovaries and/or uterus). The definition of childbearing potential may be adapted for alignment with local guidelines or requirements. b. Examples of contraceptive methods with a failure rate of <1% per year include bilateral tubal ligation, male sterilization, established and proper use of hormonal contraceptives that inhibit ovulation, hormone-releasing intrauterine devices, and copper intrauterine devices. i. Contraception methods that do not result in a failure rate of < 1% per year such as cap, diaphragm, or sponge with spermicide, or male or female condom with or without spermicide, are not acceptable. ii. The reliability of sexual abstinence should be evaluated in relation to the duration of the clinical trial and the preferred and usual lifestyle of the participant. Periodic abstinence (e.g., calendar, ovulation, symptothermal, or postovulation methods) and withdrawal are not acceptable methods of contraception.

[0385] 6) For men: agreement to remain abstinent or use contraceptive measures and agreement to refrain from donating sperm, as defined below: a. With female partners of childbearing potential, men must remain abstinent or use a condom plus an additional contraceptive method that together result in a failure rate of <1% per year during the treatment period and for at least 120 days (30 days plus a 90-day spermatogenesis cycle) after the last dose of study intervention. Men must refrain from donating sperm during this same period.

[0386] The following exclusion criteria is used for this study.

[0387] 1) Established diagnosis of cardiac amyloidosis.

[0388] 2) Established diagnosis of systemic amyloidosis (e.g., renal AL or ATTR peripheral neuropathy) without known cardiac involvement. Participants who are amyloid positive only with carpal tunnel tissue or laminectomy are allowed as long as they do not have other known organ involvement.

[0389] 3) Receiving therapy with an approved treatment (e.g., tafamadis) or in a clinical trial for treatment for ATTR cardiac amyloidosis at time of enrollment. For AL and ATTR: Patients may enter the screening period of a clinical trial for treatment after the ICF is signed and participant is enrolled in this trial but may not receive an experimental therapy until after the Day 30 safety follow-up visit in this trial.

[0390] 4) Is pregnant or breast-feeding.

[0391] 5) Is mentally or legally incapacitated, has significant emotional problems at the time of the study, or has a history of psychosis.

[0392] 6) Has a known allergy to potassium iodide.

[0393] 7) Receiving hemodialysis or peritoneal dialysis.

[0394] 8) eGFR less than 15ml/min/1.73m2.

[0395] 9) Myocardial infarction within three (3) months of screening.

[0396] 10) Has severe claustrophobia or any medical condition that would prevent completion of the imaging protocol.

[0397] 11) Has any illness that, in the opinion of the investigator, might confound the results of the study or pose additional risk to the participant.

[0398] 12) Has received heparin or heparin analogs (e.g., enoxaparin, dalteparin, fondaparinux) within seven (7) days prior to ¹²⁴I-p5+14 administration.

[0399] 13) Known uncorrected thyroid disorders (other than mild elevation of thyroid stimulating hormone with normal T4) Subject Population and Identification

[0400] The study will enroll participants with suspected cardiac amyloidosis. To ensure that the enrollment requirements for the primary endpoint are met, enrollment will continue until at least 100 participants with positive cardiac amyloidosis (based on adjudication committee assessment) and 45 participants with negative cardiac amyloidosis (based on adjudication committee assessment) are enrolled. An independent Clinical Adjudication Committee with expertise in cardiac amyloidosis will be established to review the information obtained during the diagnostic evaluation (e.g., clinical history and laboratories, endomyocardial biopsy, extracardiac biopsy, echocardiograms, cardiac MR, and bone avid tracer cardiac SPECT) to determine if the data support a diagnosis of cardiac amyloidosis.

[0401] The screening period is up to 30 days. Eligibility criteria will be confirmed and informed consent will be obtained. In women of child bearing potential (WOCBP), serum pregnancy test (stat serum P-hCG pregnancy test) will be obtained prior to administration of ¹²⁴I- p5+14 for all WOCBP. The results of the pregnancy test must be available and be confirmed as negative prior to ¹²⁴I-p5+14 administration in all WOCBP.

[0402] The treatment-emergent period is from Day 1 through Day 30. If any nuclear medicine studies are conducted (e.g., SPECT with bone-avid tracers) prior to I¹²⁴I-p5+ 14 administration then the Study Day 1 visit should occur no earlier than 24 hours after the most recent nuclear medicine scan. If a Tc-99m labeled SPECT scan is conducted after ¹²⁴I-p5+14 PET/CT study, it may be essential to wait until on or after the Day 5 visit to minimize down scatter from ¹²⁴I-p5+14 into the SPECT scan.

[0403] The Standard of Truth (SoT) Diagnostic Evaluation Period is for the diagnosis of cardiac amyloidosis. If all required diagnostic tests are not completed by Day 30, the diagnostic evaluation period extends until either the last diagnostic test is completed or until Day 60 whichever is earlier.

Study Interventions and Imaging Protocol

[0404] The subjects will receive a single dosage of ¹²⁴I-p5+14 during the Day 1 visit at a dosage level of 1 mCi (±10%) with no more than 2mg of p5+14. ¹²⁴I-p5+14 is delivered via intravenous push at a rate of ~1 mL per 5 seconds. [0405] Prior to administration of ¹²⁴I-p5+14: 1) A serum pregnancy test (stat serum P- hCG pregnancy test) will be obtained and confirmed as negative for all WOCBP prior to administration of ¹²⁴I-p5+14, 2) participants will begin therapy with KI 130 mg (e.g., iOSAT, Potassium Iodide Oral Solution USP, 65 mg/mL) orally once every day starting on day 1 and lasting for 3 days beginning greater than 30 minutes prior to administration of ¹²⁴I-p5+14 to reduce radioactive iodine uptake in the thyroid gland, 3) record heart rate, blood pressure, body weight, height, and concomitant medications, 4) a cohort of approximately 25 participants will have triplicate 12-lead Electrocardiograms (ECGs) for assessing corrected QT (QTc) intervals obtained within 2 hours prior to administration of ¹²⁴I-p5+14.

[0406] After completion of ¹²⁴I-p5+14 administration: 1) The cohort of approximately 25 participants with a baseline QTc evaluation will have triplicate 12-lead ECGs, 2) Participants will undergo a PET/CT scan.

[0407] PET/CT imaging occurs at the Day 1 visit after administration of ¹²⁴I-p5+14. Participants will receive a PET/CT scan from base of crown to upper thigh 4 hours (± 60 min) after administration of ¹²⁴I-p5+14. The total PET/CT scan time is estimated to be 45 minutes including 20 minutes in the cardiac bed position.

[0408] All participants will have a baseline 12-lead ECG obtained during screening. A cohort of approximately 25 participants will have triplicate ECGs for assessing QTc intervals within 2 hours prior to administration of ¹²⁴I-p5+14, immediately after the end of ¹²⁴I-p5+14 administration and 30 (+ 10) minutes following administration of ¹²⁴I-p5+14.

Image Interpretation

[0409] Participants will be classified into one of the following categories based on (i) visual evaluation of PET/CT images by independent readers and (ii) cardiac amyloid disease status based on the clinical truth standard: a) True Positives (TP): Participants with visually positive cardiac uptake of ¹²⁴I-p5+14 from PET/CT images and confirmed positive cardiac amyloidosis by the truth standard, b) True Negatives (TN): Participants with visually negative cardiac uptake of ¹²⁴I-p5+14 from PET/CT images and confirmed negative cardiac amyloidosis by the truth standard, c) False Positives (FP): Participants with visually positive cardiac uptake of ¹²⁴I-p5+14 from PET/CT images and confirmed negative cardiac amyloidosis by the truth standard, d) False negatives (FN): Participants with visually negative cardiac uptake ¹²⁴I-p5+14 from PET/CT images and confirmed positive cardiac amyloidosis by the truth standard.

[0410] Sensitivity is defined as the number of TP participants divided by the sum of TP and FN participants: Sensitivity = TP/(TP+FN).

[0411] Specificity is defined as the number of TN participants divided by the sum of TN and FP participants: Specificity = TN/(TN+FP).

Endpoints

[0412] The primary objective of this study is to evaluate the efficacy of ¹²⁴I-p5+14 for diagnosing cardiac amyloidosis. The corresponding co-primary endpoints are as follows: 1) The sensitivity of PET/CT imaging with ¹²⁴I-p5+14 for the diagnosis of cardiac amyloidosis based on visual scan interpretation, 2) the specificity of PET/CT imaging with ¹²⁴I-p5+14 for the diagnosis of cardiac amyloidosis based on visual scan interpretation. The co-primary hypotheses are: 1) Null: Sensitivity of imaging with ¹²⁴I-p5+14 for the diagnosis of cardiac amyloidosis = 0.65, alternative: Sensitivity of imaging with ¹²⁴I-p5+14 for the diagnosis of cardiac amyloidosis >0.65 and 2) null: Specificity of imaging with ¹²⁴I-p5+14 for the diagnosis of cardiac amyloidosis = 0.55; alternative: Specificity of imaging with ¹²⁴I-p5+14 for the diagnosis of cardiac amyloidosis >0.55. Sensitivity and specificity will be calculated for each of the three readers. The study will be considered successful if the null hypotheses for both sensitivity and specificity are rejected by at least the same 2 out of 3 readers. A summary of sensitivity and specificity will be provided with 2- sided 95% confidence intervals (Cis) using Exact method. For each of sensitivity and specificity, if the null hypothesis above is rejected by the exact binomial test, then the lower bound of the 2- sided 95% CI will mathematically be above the threshold of 65% (sensitivity) or 55% (specificity) for the co-primary endpoints.

Subgroup analyses of the primary endpoint will be performed on the following populations using two-sided, 95% confidence intervals (a = 0.025): 1) Systemic amyloidosis type (AL, ATTR), 2) Gender (female, male), 3) Age (age >65, age <65). Example 6: Early Cardiac Amyloid Detection by PET/CT Imaging of ¹²⁴I-p5+14 compared to 99mTc-PYP

[0413] To assess the possible consequences of switching between the diagnostic methods using PET/CT imaging of ¹²⁴I-p5+14 and 99mTc-PYP, 24 individuals who were previously tested for cardiac amyloidosis were reevaluated with PET/CT imaging of ¹²⁴I-p5+14. The PET/CT imaging of ¹²⁴I-p5+14 was conducted according to the methods described in Example 1.

[0414] The results are shown below in Table 13. Of the 7 individuals that tested positive for cardiac amyloid with 99mTc-PYP, all 7 of the individual tested positive for cardiac amyloid with ¹²⁴I-p5+14. Of the 17 individuals that tested negative for cardiac amyloid with 99mTc-PYP, 11 tested positive for cardiac amyloid with PET/CT imaging of ¹²⁴I-p5+14. These results demonstrate the increased sensitivity for detecting cardiac amyloid with ¹²⁴I-p5+14 compared with 99mTc-PYP.

Table 13: Detecting Cardiac Amyloid with ¹²⁴I-p5+14 and 99mTc-PYP

Example 7: Diagnostic Thresholds using ¹²⁴I-p5+14 uptake

[0415] Organ specific uptake of ¹²⁴I-p5+14 was calculated in 16 individual without systemic amyloidosis and 27 individuals with systemic amyloidosis (AL, ATTR or other) by quantifying organ specific SUVR using computer vision analysis of PET/CT images from each individual. Organ specific SUVR values were computed for the liver, spleen, kidneys, pancreas, hear, and adrenal glands.

[0416] Automated segmentation of the organs was used to quantify cardiac uptake of the radiotracer. The heart and aorta were automatically segmented on the CT data using a 3D pretrained convolutional neural network. The contours were applied to the PET data for quantitation of mean standardized uptake value, and other uptake parameters in the heart. [0417] Diagnostic thresholds were for each organ specific SUVRmean value by computed by calculating the 97.5^th percentile in the organ specific SUVRmean values for the healthy individuals. Diagnostic thresholds were also calculated for each organ for SUVRmax , the standard deviation of uptake in the organ (SUVRhetero), SUVRpeak, the sum of all uptake in the organ normalized by the voxel size of the image (SUVRtotai), and the coefficient of variation calculated as SUVRhetero divided by SUVRmean (SUVRcov) using the same method.

[0418] An individual was diagnosed with systemic amyloidosis if amyloid is detected in an organ above the thresholds in Table 14..

Table 14: SUVR Threshold values by organ

Claims

1. A method of diagnosing an amyloid-related disease at an early stage in an individual at risk for developing the amyloid-related disease comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b. detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid-related disease, wherein the amyloid-related disease is in an early stage of the amyloid-related disease.

2. The method of claim 1, wherein the individual is determined to be at risk for an amyloid- related disease based upon the presence of a genetic mutation, having multiple myeloma, having amyloid positive laminectomy tissue, having an amyloid positive tissue from carpal tunnel release surgery, having a monoclonal gammopathy of unknown significance (MGUS), having heart failure with preserved ejection fraction (HFpEF), having heart failure with reduced ejection fraction (HFrEF), being from susceptible ethnic populations, or being elderly.

3. The method of claim 2, wherein the genetic mutation is in the transthyretin protein.

4. The method of claim 2, wherein the genetic mutation is in the fibrinogen ex protein.

5. The method of any one of claims 1-3, wherein the individual does not have symptoms of amyloidosis.

6. The method of any one of claims 1-3, wherein the individual has neuropathic symptoms of an amyloid disease.

7. The method of any of claims 1-6, wherein the individual has previously been diagnosed as not having an amyloid related disease.

8. A method of diagnosing an amyloid-related disease at an early stage in an individual suspected of having an amyloid-related disease comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b. detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid-related disease, wherein the amyloid-related disease is in an early stage of the amyloid-related disease.

9. A method of determining prognosis of an individual having an amyloid-related disease comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; and c. comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time to determine the prognosis of the individual.

10. The method of claim 8, wherein the prognosis of an individual having an amyloid-related disease is based on detecting an amount of amyloid-reactive peptide in the heart alone.

11. The method of claim 8, wherein the prognosis of an individual having an amyloid-related disease is based on detecting an amount of amyloid-reactive peptide in the heart and kidneys.

12. The method of claim 8, wherein the prognosis of an individual having an amyloid-related disease is based on detecting an amount of amyloid-reactive peptide in the heart, kidneys, and all other organs.

13. A method of treating an amyloid-related disease comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; b. detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label in a tissue or organ of the individual ,and c. administering a treatment for the amyloid-related disease if the amount of amyloid-reactive peptide is above a threshold.

14. The method of claim 13, wherein the individual has an early stage amyloid-related disease.

15. A method of monitoring treatment of an amyloid-related disease in an individual comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b. administering a treatment for an amyloid-related disease; c. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; and d. comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time to determine whether the treatment is effective.

16. The method of any one of claims 1-15, further comprising administering an amyloidreactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time, optionally a third time a fourth time, and/or a fifth time.

17. The method claim 15 or 16, wherein the first time and the second time are at least six weeks apart.

18. A method of selecting a treatment for an amyloid-related disease in an individual comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual; and b. detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual, wherein if amyloid is detected in the heart a treatment for the amyloid-related disease is administered and wherein if amyloid is not detected in the heart, an alternative therapy is administered.

19. A method of managing the treatment for an amyloid-related disease in an individual comprising a. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting an amount of amyloid-reactive peptide by detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a first time; b. administering a treatment for an amyloid-related disease; c. administering an amyloid-reactive peptide comprising the amino acid sequence set forth in any one of SEQ ID NOs:l-14 conjugated to a detectable label to the individual and detecting the amount of the detectable label at a tissue or organ of the individual to quantify amyloid in the individual a second time; d. comparing the amyloid quantified in a tissue or organ the first time with the amyloid quantified in the tissue or organ the second time; and e. adjusting the treatment for the amyloid-related disease.

20. The method of claim 19, wherein if the amyloid disease is stable between the first and second times treatment is be modified.

21. The method of claim 19, wherein if the amyloid burden increases treatment is reinitiated.

22. The method of claims 9-12 and 14-21, wherein the amount of amyloid-reactive peptide above a threshold indicates that the individual has the amyloid-related disease.

23. The method of claim 22, wherein the amyloid-related disease is in an early stage of the amyloid-related disease.

24. The method of any one of claims 1-23, wherein the amyloid-reactive peptide comprises SEQ ID NO: 13.

25. The method of any one of claims 1-24, wherein the detectable label is a radiolabel.

26. The method of any one of claims 1-25, wherein the detectable label is selected from the group consisting of ⁿC, ¹⁸F, ^{n i}In, "^mTc, ⁸⁹Zr, ⁶⁸Ga, and ¹²³I, ¹²⁴I, and ¹²⁵I.

27. The method of any one of claims 1-26, wherein the detectable label is ¹²⁴I.

28. The method of any one of claims 1-27, wherein a dose of about 0.1 to about 25 mCi of 1²⁴I-labeled amyloid-reactive peptide is administered to the individual.

29. The method of any one of claims 1-28, wherein a dose of about 0.3 mCi, 1 mCi, or about 2 mCi of ¹²⁴I-labeled amyloid-reactive peptide is administered to the individual.

30. The method of any one of claims 1-29, wherein a dose of about of aboutl mCi (±10%) of ¹²⁴I-labeled amyloid-reactive peptide is administered to the individual.

31. The method of any one of claims 1-30, comprising administering a dose of about 20 mCi of Tc-99 to the individual.

32. The method of any one of claims 1-31, wherein about 0.3 mg, 1 mg, 1.5 mg, or about 2 mg of amyloid-reactive peptide is administered to the individual.

33. The method of any one of claims 1-32, wherein the amyloid-reactive peptide is administered intravenously.

34. The method of any one of claims 1-33, further comprising determining an organ- specific standard uptake value ratio for an organ within an individual.

35. The method of claim 34, wherein the organ- specific SUVR for the individual is selected from the group consisting of SUVR mean, SUVR max, and SUVR peak.

36. The method of any one of claims 1-35, further comprising determining an organ- specific SUV for the individual.

37. The method of claim 36, wherein the organ- specific SUV for the individual is selected from the group consisting of SUV mean, SUV max, and SUV peak.

38. The method of any one of claims 1-37, further comprising determining an organ- specific percent injected dose/gram (%ID) for the individual.

39. The method of any one of claims 1-38, wherein the sensitivity for detecting amyloid using the amyloid-reactive peptide is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 99% or at least 100%.

40. The method of any one of claims 1-39, wherein the sensitivity is about 99% or about 100%.

41. The method of any one of claims 1-40, wherein the specificity of the amyloid-reactive peptide is at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 99% or at least 100%.

42. The method of any one of claims 1-41, wherein the specificity of the amyloid-reactive peptide is about 99% or 100%.

43. The method of any one of claims 1-42, further comprising determining one or more health related quality of life measures for the individual.

44. The method of any one of claims 1-43, further comprising detecting one or more biomarkers associated with the amyloid-related disease.

45. The method of claim 44, wherein the biomarker associated with amyloid-related disease is selected from the group consisting of Troponin T, NTproBNP, urine protein levels, UACR, EGFR, and alkaline phosphatase levels.

46. The method of any one of claims 1-45, wherein the tissue or organ of the individual is selected from the group consisting of lung, fat, heart, kidney, pancreas, joints, spine, liver, spleen, adrenal gland, bone lesions, choroid plexus, pituitary gland, uterus, bone marrow, musculoskeletal tissue, gastrointestinal, and prostate gland.

47. The method of claims 1-8, 13, and 22-46, wherein the threshold is an SUVR mean threshold value.

48. The method of claim 47, wherein the SUVR mean threshold value is approximately 1.0,

1.1, 1.2, 1.3, 1.4, 1.5, or 1.6 if the organ or tissue is the liver; the SUVR mean threshold value is approximately 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, or 1.5 if the organ or tissue is the spleen; the SUVR mean threshold value is approximately 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1,

2.2, or 2.3 if the organ or tissue is the kidneys; the SUVR mean threshold value is approximately 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, or 1.7 if the organ or tissue is the pancreas; the SUVR mean threshold value is approximately 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, or 2.1 if the organ or tissue is the heart ;or the SUVR mean threshold value is approximately 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, or 1.4 if the organ or tissue is the adrenal gland.

49. The method of claim 48, wherein the SUVR mean threshold value is 1.31 if the organ or tissue is the liver, the SUVR mean threshold value is 1.21 if the organ or tissue is the spleen, the SUVR mean threshold value is 1.88 if the organ or tissue is the kidneys, the SUVR mean threshold value is 1.40 if the organ or tissue is the pancreas, the SUVR mean threshold value is 1.19 if the organ or tissue is the heart or the SUVR mean threshold value is 1.35 if the organ or tissue is the adrenal gland.

50. The method of claims 1-8, 13, and 22-46, wherein the threshold is an SUVR max threshold value.

51. The method of claim 50, wherein the SUVR max threshold value is 10.6, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, or 16 if the organ or tissue is the liver; the SUVR max threshold value is 3.8, 4, 4.5, 5, 5.5, or 5.9 if the organ or tissue is the spleen; the SUVR max threshold value is 7.7, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, or 11.7 if the organ or tissue is the kidneys; the SUVR max threshold value is 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, or 11.4 if the organ or tissue is the pancreas; the SUVR max threshold value is 4.9, 5, 5.5, 6, 6.5, 7, or 7.5 if the organ or tissue is the heart; or the SUVR max threshold value is 1, 1.1, 1.2, 1.3, 1.4, 1.5, or 1.6 if the organ or tissue is the adrenal gland.

52. The method of claim 51, wherein the SUVR max threshold value is 13.26 if the organ or tissue is the liver, the SUVR max threshold value is 4.86 if the organ or tissue is the spleen, the SUVR max threshold value is 9.68 if the organ or tissue is the kidneys, the SUVR max threshold value is 9.48 if the organ or tissue is the pancreas, the SUVR max threshold value is 6.20 if the organ or tissue is the heart or the SUVR max threshold value is 1.31 if the organ or tissue is the adrenal gland.

53. The method of any one of claims 1-52, further comprising performing a cardiac biopsy if amyloid is detected in the heart.

54. The method of any one of claims 1-53, further comprising performing additional amyloid imaging on the individual.

55. The method of any one of claims 1-54, further comprising performing additional amyloid imaging on the individual before administering the amyloid reactive peptide.

56. The method of claim 55, wherein the additional amyloid imaging on the individual comprises ECHO, CMR, bone scintigraphy or positron emission tomography imaging.

57. The method of claim 56, where in the additional amyloid imaging on the individual further comprises a tracer selected from the group consisting of "^mTc-PyP, "^mTc-DPD, "^mTc-HMDP, "^mTc-MDP other bone scintigraphy tracers, ¹²⁴I, and ¹⁸F-florbetapir, ¹⁸F- flutemetamol, and ¹⁸F-florbetaben.

58. The method of any one of claims 1-57, wherein the diagnosis, prognosis, or response, is confirmed by a measure of the health-related quality of life of the individual, the presence or amount of one or more biomarkers associated with the amyloid-related disease, a cardiac biopsy, and/or additional amyloid imaging of the individual.

59. The method of any one of claims 1-58, wherein the individual is diagnosed with amyloid cardiomyopathy .

60. The method of any one of claims 1-59, wherein the individual is suspected of having amyloid cardiomyopathy.

61. The method of any one of claims 1-60, wherein the amyloid-related disease is systemic or localized amyloidosis.

62. The method of any one of claims 1-61, wherein the amyloid-related disease is cardiac amyloidosis.

63. The method of any one of claims 1-62, wherein the amyloid-reactive peptide has panamyloid specificity.

64. The method of any one of claims 1-63, wherein the amyloid-reactive peptide binds to amyloid of immunoglobulin light chain (AL), immunoglobulin heavy chain (AH), P2- microglobulin (Ap2M), transthyretin (ATTR wild type; ATTR variant), apolipoprotein Al (AApoAI), apolipoprotein All (AApoAII), apolipoprotein AIV (AApoAIV), gelsolin (AGel), apolipoprotein C-II (AApoCII), apolipoprotein C-II (AApoCIII), lysozyme (ALys), leukocyte chemotactic factor (ALECT2), fibrinogen a variants (AFib), cystatin variants (ACys), calcitonin (ACal), lactadherin (AMed), islet amyloid polypeptide (AIAPP), prolactin (APro), insulin (Alns), prior protein (APrP); a-synuclein (AaSyn), tau (ATau), atrial natriuretic factor (AANF), IAAP, ALP4, or ALpi.

65. The method of any one of claims 1-64, wherein the amyloid reactive peptide is detected using PET, PET/CT, gamma scintigraphy, SPECT, and/or SPECT/CT.

66. The method of any one of claims 1-65, wherein the amyloid-related disease is selected from the group consisting of AL, AH, Ap2M, ATTRv, ATTRwt, AA, AApoAI, AApoAII, AApoCII, AApoCIII, AGel, ALys, ALECT2, AFib, ACys, ACal, AMed, AIAPP, APro, Alns, APrP, and Ap amyloidosis.

67. The method of claim 66, wherein the amyloid-related disease is cardiac AL amyloidosis.

68. The method of claim 66, wherein the amyloid-related disease is cardiac ATTR amyloidosis.

69. The method of any one of claims 1-68, wherein the individual has a genetic predisposition to an amyloid-related disease.

70. The method of any one of claims 1-69, wherein the individual has a family history of an amyloid-related disease.

71. The method of any one of claims 1-70, wherein the individual is elderly.

72. The method of any one of claims 1-71, wherein the individual has an early stage of an amyloid-related disease.

73. The method of any one of claims 1-72, wherein the individual has an early stage of an systemic amyloidosis.

74. The method of any one of claims 1-73, wherein the individual has an early stage of cardiac amyloidosis.

75. The method of any one of claims 1-74, wherein the individual has an early stage of AL amyloidosis.

76. The method of claim 75, wherein the early stage of AL amyloidosis is diagnosed according to the Mayo Clinic system.

77. The method of claim 76, wherein the early stage of AL amyloidosis is stage 1 AL amyloidosis.

78. The method of any one of claims 1-77, wherein the individual has an early stage of ATTR amyloidosis.

79. The method of claim 78, wherein the early stage of ATTR amyloidosis comprises stage 1 ATTR amyloidosis.

80. The method of any one of claims 1-12, 16-18, and 20-79, further comprising administering a treatment for the amyloid-related disease.

81. The method of any one of 13-15, 19 and 80, wherein the treatment for the amyloid- related disease is selected from the group consisting of transthyretin stabilizers (e.g. tafamidis, acoramidis), transthyretin silencers (e.g. Patisiran, Inotersen, Vutrisiran, Eploetersen), gene editing approaches, anti-amyloid approaches utilizing monoclonal antibodies, treatments targeting plasma cell clones (e.g. Daratumumab, Bortezomib), and an antibody-peptide fusion comprising an antibody-peptide fusion protein comprising a second amyloid-reactive peptide and an antibody that binds to amyloid fibrils.

82. The method of claim 81, wherein the second amyloid-reactive peptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 1-14 comprising 0, 1, 2, 3, or 4 amino acid substitutions, insertions, or deletions.

83. The method of claim 81 or 82, wherein the antibody-peptide fusion protein comprises a heavy chain and a light chain and wherein the amyloid-reactive peptide is linked to at the C-terminal end of the light chain of the antibody via a spacer.

84. The method of any one of claims 81-83, wherein the antibody-peptide fusion protein comprises:

(ii) an antibody that binds to a human amyloid fibril, wherein the antibody comprises a heavy chain and a light chain, wherein the heavy chain of the antibody comprises a heavy chain variable region (VH) and the light chain of the antibody comprises a light chain variable region (VL), wherein the VH comprises a CDR-H1 comprising the amino acid sequence set forth in SEQ ID NO: 106, a CDR-H2 comprising the amino acid sequence set forth in SEQ ID NO: 107, and a CDR-H3 comprising the amino acid sequence set forth in SEQ ID NO: 108, and the VL comprises a CDR-L1 comprising the amino acid sequence set forth in SEQ ID NO: 103, a CDR-L2 comprising the amino acid sequence set forth in SEQ ID NO: 104, and a CDR-L3 comprising the amino acid sequence set forth in SEQ ID NO: 105; wherein the amyloid-reactive peptide and antibody are linked at the C-terminal end of the light chain, and wherein the amyloid-reactive peptide is linked to the antibody via a spacer comprising an amino acid sequence set forth in SEQ ID NO: 83.

85. The method of any one of claims 1-84, wherein a peptide comprising the amyloidreactive peptide and an N-terminal leader sequence is administered to the individual.

86. The method of claim 85, wherein the peptide comprising the amyloid reactive peptide comprises the amino acid sequence set forth in SEQ ID NO: 100.

87. The method of claim 86, wherein a detectable label is bound to one or more amino acids at positions 1 to 6 of the amino acid sequence set forth in SEQ ID NO: 100.

88. The method claim 87, wherein the detectable label is ¹²⁴I.

89. The method of claim 88, wherein the ¹²⁴I is bound to amino acid 4 of SEQ ID NO: 100.

90. The methods of any of claim 1-89, further comprising administering potassium iodide to the individual.

91. The method of claim 90, wherein the administering potassium iodide comprises administering 130 mg of the potassium iodide to the patient for seven days starting one day before the administration of the amyloid reactive peptide.

92. The method of claim 91, wherein the administering potassium iodide comprises administering 130 mg of the potassium iodide to the patient for three days starting about 30 minutes before the administration of the amyloid reactive peptide.

93. The method of any of claim 90-92, wherein the administration of potassium iodide is oral administration.

94. A peptide comprising the amino acid set forth in SEQ ID NO: 100, wherein the peptide comprises a detectable label bound to one or more amino acids at positions 1 to 6.

95. The peptide of claim 94, wherein the detectable label is ¹²⁴I.

96. The peptide of claim 95, wherein the ¹²⁴I is bound to amino acid 4 of SEQ ID NO: 100.