Bayer PET tracer meets cardiac amyloidosis endpoints

Bayer has reported positive topline phase 3 results for I-124 evuzamitide, an investigational PET/CT radiotracer being studied for the diagnosis of cardiac amyloidosis.

The REVEAL study met its primary endpoints for sensitivity and specificity based on visual scan interpretation, according to Bayer. The company said it plans to present complete results at an upcoming scientific congress and submit the agent for regulatory approval with the U.S. Food and Drug Administration and other health authorities.

REVEAL, short for Research with I-124 Evuzamitide to Elucidate Cardiac Amyloidosis, is an investigator-initiated phase 3 clinical trial sponsored by Brigham and Women’s Hospital in Boston. The multicenter, open-label, single-arm study evaluated 170 adults with suspected cardiac amyloidosis at 19 U.S. centers.

The trial compared the investigational imaging agent with clinical standard-of-care diagnosis. Secondary analyses assessed diagnostic performance in transthyretin amyloidosis and light-chain amyloidosis subtypes, according to Bayer.

Cardiac amyloidosis occurs when abnormal amyloid proteins build up in the heart, leading to stiffening of cardiac tissue and impaired function. The condition can be difficult to diagnose, and patients may undergo multiple specialist visits and imaging procedures before receiving an accurate diagnosis.

Bayer said there is currently no single noninvasive test that can reliably detect and diagnose cardiac amyloidosis or quantify and monitor myocardial amyloid burden. That unmet need gives PET/CT tracers such as I-124 evuzamitide potential importance in clinical pathways if regulatory review supports approval.

I-124 evuzamitide, also known as AT-01, is designed to visualize amyloid deposits in the heart. Bayer said the agent previously received FDA breakthrough therapy designation for PET imaging in patients with suspected or known cardiac amyloidosis. It also has orphan drug status for light-chain amyloidosis and transthyretin amyloidosis in the U.S. and EU.

The radiotracer came to Bayer through its acquisition of 2 cardiac amyloidosis imaging agents from Attralus. In January, Bayer said AT-01 was in phase 3 development and that AT-05, a technetium-99m SPECT tracer, was in phase 1 development.

The company has not yet released the full numerical results from REVEAL. For now, the reported milestone is that the study met its main diagnostic-performance endpoints, not that the agent has been approved for clinical use.

Further details from the upcoming scientific presentation will be important for nuclear medicine, cardiology, and radiology teams. Those data should clarify diagnostic performance across amyloidosis subtypes, safety findings, and how PET/CT with I-124 evuzamitide could fit alongside existing echocardiography, cardiac MRI, nuclear scintigraphy, laboratory testing, and biopsy pathways.