At the Heart Failure Society of America annual meeting, researchers presented results from the phase III REVEAL study of the investigational PET/CT tracer 124I-evuzamitide. Among 170 people with suspected cardiac amyloidosis, the tracer identified the condition with 93.5% sensitivity and 86.0% specificity, with a negative predictive value of 94.1%. It performed similarly well for both light-chain (AL) and transthyretin (ATTR) amyloidosis, according to the study's lead author, Mathew Maurer of Columbia University Irving Medical Center.
The tracer proved especially useful in early, low-burden disease. In detecting early ATTR, evuzamitide PET outperformed standard bone scintigraphy (93% vs 68%, P=0.016). It also flagged more cases among patients with NT-proBNP under 350 ng/L (89% vs 74%) and those with left ventricular wall thickness under 12 mm (100% vs 78%). No patient detected by bone scintigraphy was missed by the PET tracer. Maurer noted that a single test detecting both AL and ATTR without biopsy could allow earlier diagnosis and timely treatment.
The study also suggested the tracer could quantify amyloid load over time, potentially tracking treatment response. However, the authors acknowledged limitations, including a 60-day follow-up, a relatively small number of AL patients, and the reference standard being constrained by available clinical data. Bayer said it plans to submit the tracer for regulatory approval based on these findings.