New Method to Potentially Diagnose Amyloidosis

Jonathan Wall, PhD, Director of the University of Tennessee Graduate School of Medicine’s Amyloidosis and Cancer Theranostics Program and Co-founder & Interim Chief Scientific Officer at Attralus, discusses data from a phase 1/2 trial evaluating the ability of AT-01 to detect amyloid deposits by PET/CT imaging in adults with a confirmed diagnosis of immunoglobulin light chain-associated (AL) amyloidosis. Data from this study were recently presented at The American Society of Hematology Meeting & Exposition (ASH 2021).

AL amyloidosis is a rare blood disorder associated with the overproduction of amyloid, which leads to the deterioration of vital organs, most notably the heart, kidneys, and liver.

As Dr. Wall explains, there are currently no approved methods in the United States for the non-invasive detection of amyloid distribution in patients with AL amyloidosis. To address this, Attralus developed the synthetic peptide radiotracer, AT-01, which is suitable for PET/CT imaging. Preclinical studies have demonstrated the specific reactivity of AT-01 with diverse forms of amyloid.

Dr. Wall goes on to explain that the purpose of the phase 1/2 trial was to assess the safety and efficacy of a single-injection dose of AT-01 for imaging amyloid deposits by using PET/CT imaging in patients with systemic amyloidosis, including those with AL amyloidosis. 52 patients were recruited along with 5 healthy controls. 23 of these patients had AL amyloidosis, all of whom completed the study.

In healthy subjects, radioactivity was observed in the parotid, salivary and thyroid glands, saliva, stomach lumen and urine in the ureters and bladder, consistent with the biodistribution of free radioiodide. No uptake in abdominothoracic organs was observed in these patients. In contrast, patients with AL amyloidosis exhibited uptake in the heart (71% of patients), kidneys (61%), spleen (43%), liver (30%), as well in the pancreas, lung, bone marrow and other sites. The patient-based sensitivity (i.e., patients with visual uptake in at least one anatomic site) was 96% (22/23). The organ-based sensitivity (i.e., clinically positive heart, liver, spleen or kidney that exhibited visual uptake of AT-01) was 86% (13/14 heart; 3/3 liver; 1/1 spleen; 7/10 kidney). Additionally, clinically undetected amyloid was observed in numerous anatomic sites with amyloid visualized by AT-01 in 68% more abdominothoracic organs than what was documented in patients’ clinical records.

• Category

  Amyloidosis