Clinical update on the detection of Immunoglobulin Light Chain(AL) amyloidosis and differentiation between AL and Transthyretin (ATTR) amyloidosis using AT-01, a novel, potential first-in-class diagnostic for systemic amyloidosis

‍SOUTH SAN FRANCISCO, Calif., November 5, 2020 – Attralus, a biopharmaceutical company focused on creating transformative medicines to improve the lives of patients with systemic amyloidosis, will present clinical data from its ongoing Phase1/2 trial assessing AT-01, the Company’s novel pan amyloid imaging agent, at the 62nd Annual American Society of Hematology Meeting andExposition (ASH 2020) taking place virtually fromDecember 5 – 8, 2020. The data will be presented by Dr. Jonathan Wall, an internationally known expert in the amyloidosis field, the co-founder of Attralus, and the scientist behind Attralus’ AT-01 technology.

The data will provide an update on the detection of AL amyloidosis inpatients as well as the differentiation of AL amyloidosis from ATTR amyloidosis, using AT-01 imaging. AL is a multi-systemic disease associated with deposition of amyloid fibrils within the heart, kidney, and other organs, resulting in cytotoxicity, organ dysfunction and ultimately death. Presently, there are no approved imaging agents in the U.S. for the diagnosis of systemic amyloidosis, including AL amyloidosis.

The following poster will be made available onDecember 6th at 7 a.m. PST:                  

Abstract Number: 2212

Title: Detection of Systemic AL Amyloidosis and Differentiation of AL from ATTR Using 124I-p5+14PET Imaging

Lead Authors: Jonathan Wall, Eric Heidel, Alan Stuckey & Emily Martin

Results: Analysis of PET images indicated retention of 124I-p5+14 (AT-01) in the heart, kidneys, liver, spleen, pancreas, bone marrow, lung, and adrenal gland of AL patients. Cardiac uptake of the radiotracer was observed in 70% of AL patients and kidney uptake was observed in 69% of patients. Additionally, liver and spleen retention of 124I-p5+14 was observed in 38% and 61%of AL patients, respectively, and the patient-based sensitivity for AL patients was 93% (14/15).  

Results also show that by using an ROC analysis of SUVR organ ratios, it was possible to differentiate AL from ATTR patients with p = 0.002and an AUC of 0.96. A cutoff value of 1.40 yielded a 100% sensitivity and75% specificity for diagnosing ATTR relative to AL from the image data.

“We are excited and honored to present additional data on AT-01, our potential first in class diagnostic for amyloidosis, at ASH 2020 this year,” said Spencer Guthrie, CEO of Attralus. “A majority of patients with systemic amyloidosis go undiagnosed, and those that are diagnosed, usually wait over 18 months to get an accurate diagnosis.Clearly, the detection and diagnosis of systemic amyloidosis must improve, and we are encouraged that AT-01 may help to fill this large unmet need.”

AT-01 is a novel polybasic peptide radiotracer imaging agent under clinical investigation for whole-body amyloid detection in multiple types of amyloidosis.Preliminary Phase 1/2 clinical data presented in September at ISA 2020, shows safety and efficacy of AT-01 as a pan-amyloid imaging agent that binds to many forms of systemic amyloid including AL and ATTR.  AT-01 has detected AL amyloid in the heart, kidneys, liver, spleen and lungs, and ATTR amyloid in the heart, nerves, lungs and connective tissue in the hands and spine – demonstrating the potential forAT-01 to serve as a first-in-class diagnostic for a range of systemic amyloid diseases. Additionally, amyloid was visualized in the hearts of AL and ATTR patients who have pre-symptomatic cardiac disease, potentially enabling earlier diagnosis of patients prior to the onset of symptoms.

About Attralus

Attralus, Inc. is a biopharmaceutical company focused on illuminating the systemic nature of amyloidosis and creating transformative medicines to improve the lives of patients. The company’s proprietary peptide-basedpan-amyloid targeting agents have the potential to diagnose and treat all forms and stages of systemic amyloidosis. In addition to AT-01, Attralus is developing two targeted therapeutics, which are currently in pre-clinical development for systemic amyloidosis. Attralus is focused on targeting common pathology in all systemic amyloidosis diseases, with the goal of developing treatments for all types of amyloidosis, including the majority in which there are currently no treatment options. Attralus is headquartered in South SanFrancisco and was founded in 2019 with funding from venBio Partners. For more information, visit Attralus online and on Twitter.