Bayer has signed definitive agreements to acquire two investigational molecular imaging agents from Attralus, Inc., moving the company into the diagnostic tracer space as it looks to broaden its molecular imaging footprint and strengthen its cardiovascular precision medicine strategy.
The assets include AT-01 (124-Iodine-evuzamitide), a pan-amyloid PET tracer in Phase III development, and AT-05 (PAR-Peptide + technetium-99m), a SPECT tracer in Phase I development. Both programs are designed to support diagnosis of cardiac amyloidosis and other forms of systemic amyloidosis—conditions that can be difficult to detect and are frequently underdiagnosed, even as new therapies increase the importance of identifying and monitoring disease earlier.
Bayer said the acquisition aligns with its radiology and cardiology focus by pairing diagnostic tracers with its existing imaging portfolio and global clinical and commercial infrastructure. The company also pointed to the expanding radio-diagnostic tracer market, which it estimates was valued at roughly $3 billion in 2024 and is expected to grow in the coming years.
AT-01 has received U.S. FDA Breakthrough Therapy Designation for cardiac amyloidosis and holds Orphan Drug Designation in the United States and European Union. The Phase III REVEAL study in patients with suspected cardiac amyloidosis is ongoing and, according to the companies, has completed dosing.
AT-01 is designed as a non-invasive, pan-amyloid PET imaging agent that uses a proprietary amyloid-binding peptide labeled with iodine-124 to detect multiple types of amyloid deposits across major organs, including the heart. AT-05 is intended to provide an additional diagnostic option using SPECT technology, which could expand access given the broader availability of SPECT imaging in many care settings.
Cardiac amyloidosis occurs when abnormal amyloid protein deposits build up in heart tissue, making the heart muscle thicker and stiffer and potentially leading to heart failure and rhythm problems. Bayer cited an estimate of roughly 400,000 people affected globally and emphasized that patients are often diagnosed later in the disease course, when organ damage can be irreversible.
Financial terms of the acquisition were not disclosed. Attralus said it will shift its focus to advancing its therapeutic pipeline, including AT-02, a pan-amyloid removal candidate in Phase II development, as well as next-generation programs in preclinical work.
KEY QUOTE:
“With new therapies emerging for often insufficiently treated conditions such as cardiac amyloidosis, it becomes increasingly relevant to precisely detect and monitor diseases on the molecular level. This acquisition marks our entry into diagnostic tracers. Leveraging our expertise in medical imaging – including our pipeline and portfolio in advanced fluid delivery devices for nuclear medicine – it supports our ambition to expand in the growing field of molecular imaging. Building on Attralus’ research and development expertise, we will further advance scientific progress with the aim to broaden diagnostic options and make a meaningful difference for people living with cardiac amyloidosis.”
Nelson Ambrogio, President Radiology, Bayer
“We are excited to finalize this agreement with Bayer, whose expertise and global footprint in radiology will help to accelerate the development and launch of AT-01 and AT-05, our two novel diagnostic imaging agents for systemic amyloidosis. Despite recent progress in systemic amyloidosis, most patients continue to remain undiagnosed or are diagnosed too late in their disease progression. Consistent with Attralus’ mission, we believe that these pan-amyloid imaging agents will enable earlier diagnosis and treatment, leading to improved patient outcomes. Bayer’s commitment to scientific rigor and patient impact makes them well-suited to bring these agents to clinicians and patients worldwide. Attralus will now focus on advancing its innovative pan-amyloid removal therapeutics, with AT-02 in Phase II and next generation candidates in preclinical development.”
Glen Firestone, President, Attralus
