RT Journal Article SR Electronic T1 Multi-Amyloid Reactivity of the Peptide Imaging Agent 124I-p5+14 (AT-01) in Patients with Amyloidosis. JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 144 OP 144 VO 62 IS supplement 1 A1 Jonathan Wall A1 Emily Martin A1 Alan Stuckey A1 Dustin Powell A1 Ronald Lands A1 Stephen Kennel YR 2021 UL http://jnm.snmjournals.org/content/62/supplement_1/144.abstract AB 144Objectives: Amyloidosis is a rare but invariably fatal disorder resulting from the extracellular deposition of protein aggregates. The progressive accumulation of amyloid in abdominothoracic organs and peripheral nerves results in severe morbidity, loss of quality of life, and organ dysfunction. More than 30 different proteins have been identified as components of amyloid deposits. For most patients, the whole body distribution of amyloid is based on single-organ biopsy and serum biomarkers of organ function. Using a novel amyloid imaging peptide 124I-p5+14 (AT-01), we are now developing a more complete picture of the complexity and diversity of amyloid burden in these patients and a greater understanding of the disease (NCT03678259). Methods: Patients >18 years of age with a confirmed diagnosis of amyloidosis (based on biopsy, genotyping, or imaging studies) and not requiring heparin therapy are eligible. Subjects received ~1.4 mg of 124I-p5+14 (<2 mCi) administered as a single IV bolus. PET/CT images were acquired at 5 h post injection using a Biograph 16 TruePoint with a low dose CT (120 kVp, 50 effective mAs). PET data were reconstructed using a 3DOSEM algorithm with attenuation weighting and prompt gamma correction yielding an image matrix of 168 x 168 and an image resolution of ~8 mm full width half maximum. The primary endpoints include record of adverse events, estimates of dosimetry, and a secondary endpoint of organ-specific sensitivity. Results: A diverse group of amyloid diseases have been represented in the study population - light chain (ALκ, ALλ and localized), variant transthyretin (ATTRv), wild type transthyretin (ATTRwt), leukocyte chemotactic factor 2 (ALECT2), lysozyme (ALys), gelsolin (AGel), and apolipoprotein A1 (AApoA1) associated amyloidoses. Uptake of 124I-p5+14 was observed in the organs and tissues of every type of amyloid evaluated to date. Conclusion: PET/CT imaging using 124I-p5+14 can detect at least nine different forms of amyloid present in all major organs, including the heart. The heterogeneity of organ involvement in patients with amyloidosis is complex and varied, making diagnosis challenging; however, 124I-p5+14 imaging can provide an accurate depiction of amyloid distribution for many forms of disease. Acknowledgements: Support for this work comes from the Amyloidosis and Cancer Theranostics Program gift fund. We appreciate the support of the Cancer Institute and Department of Nuclear Medicine at the University of Tennessee Medical Center. Attralus Inc. owns intellectual property associated with 124I-p5+14 (AT-01).