-Dosing initiated in proof-of-concept MATADOR Phase 2a study- -Initial results expected by year-end 2026- PALO ALTO, Calif. and NEEDHAM, Mass., June 02, 2025 (GLOBE NEWSWIRE) — Bitterroot Bio, a leader in developing innovative medicines in the field of cardio-immunology, today announced the dosing of the first patient in its proof-of-concept MATADOR Phase 2a study in Australia, a randomized, double-blinded, and placebo-controlled trial evaluating BRB-002 in patients with established atherosclerosis. BRB-002 is a novel, investigational, immunomodulating protein therapy that targets CD47 as a potential treatment option for patients with atherosclerotic cardiovascular disease (ASCVD). By targeting CD47, BRB-002 directly acts on atherosclerotic plaque through the immunomodulation of macrophages, an approach distinct from current standards of care. This mechanism holds the potential to reduce vascular inflammation, a key driver of plaque rupture, as well as plaque burden, a significant risk factor for major adverse cardiovascular events (MACE). Dosing initiation follows favorable Phase 1 single ascending dose results, presented at the American College of Cardiology (ACC) Scientific Sessions earlier this year. BRB-002 was safe at all doses tested, with no serious adverse events (SAEs) observed. Notably, there was no clinically significant impact on hematologic parameters, including no observed anemia, thrombocytopenia, or febrile neutropenia. This encouraging safety data was accompanied by robust, dose-dependent target engagement, as measured by receptor occupancy (RO) on circulating blood cells, ranging up to 100% CD47 RO at the highest doses evaluated. The ongoing proof-of-concept MATADOR Phase 2a study will evaluate the safety and tolerability of multiple doses of BRB-002 in patients with ASCVD after 13 weeks of treatment. Additional clinical endpoints include pharmacokinetics and pharmacodynamics of BRB-002, as well as the change from baseline in carotid artery plaque inflammation as measured by 18F-FDG-PET/CT imaging. The study will enroll patients with imaging-documented carotid atherosclerosis in one or more dose exploration cohorts followed by a larger expansion cohort. The Company expects to report initial results from the MATADOR Phase 2a study by year-end 2026. “Today marks a significant milestone as we initiate dosing in our proof-of-concept MATADOR Phase 2a study. While current standards of care for ASCVD, particularly lipid-lowering therapies, have improved outcomes, many patients continue to face substantial residual risk, and there is considerable need for new approaches that address different pathological pathways,” said Craig Basson, MD, PhD, Chief Medical Officer of Bitterroot Bio. “This Phase 2a study will provide crucial insights into the safety, tolerability, and biological activity of our innovative approach with BRB-002. We are optimistic that targeting atherosclerotic plaque directly may lower vascular inflammation and residual risk, ultimately improving long-term cardiovascular health for ASCVD patients.” About BRB-002BRB-002 is a novel protein therapy that is being evaluated as an investigational agent in atherosclerotic cardiovascular disease (ASCVD). BRB-002 is an immunomodulatory agent that inhibits the CD47 cell surface receptor (“don’t eat me” signal) to ameliorate the underlying causes of atherosclerosis and reduce inflammatory plaque burden. A Phase 1 clinical study of BRB-002 was completed in Australia by Bitterroot Australia Pty Ltd, a wholly owned subsidiary of Bitterroot Bio, Inc. About Bitterroot BioBitterroot Bio, Inc. is a pioneer in the field of cardio-immunology, which investigates the interplay between the immune system and cardiovascular health. Bitterroot Bio’s research seeks to uncover critical roles that immune modulators play in the progression of cardiovascular disease. By targeting these diseases in this novel way, Bitterroot Bio’s mission is to transform the lives of patients suffering from cardiovascular diseases. For more information, please visit https://www.brbio.com or follow us on Facebook LinkedIn, or X. Media Contact: Pablo Fenton (Bitterroot Bio), media@brbio.com
