BridgeBio Pharma Inc. said on Monday it has dosed the first patient in a Phase 3b/4 study evaluating acoramidis for transthyretin amyloid cardiomyopathy (ATTR-CM), a progressive heart condition.
The ASCEND-ATTR trial plans to enroll approximately 150 patients with wild-type or variant transthyretin-mediated amyloidosis. Participants will undergo annual cardiovascular magnetic resonance and cardiac echocardiography over a 36-month period to assess structural, functional, and amyloid burden changes.
Primary efficacy will be measured by responder status at Month 36, defined by improvements from baseline in left ventricular systolic function. Secondary endpoints include cardiac function and structure metrics, amyloid burden, echocardiographic measures, circulating biomarkers, and imaging assessments at Months 12, 24, and 36.
Acoramidis, marketed as Attruby, is a transthyretin stabilizer approved to reduce cardiovascular death and hospitalization in adults with ATTR-CM. The drug previously demonstrated changes in cardiac measurements in the ATTRibute-CM CMR substudy, including reductions in Left Ventricular Mass Index and Left Ventricular Stroke Volume Index, alongside evidence of amyloid regression in a subset of patients.
Safety data from the substudy showed higher rates of diarrhea (11.6% vs. 7.6%) and upper abdominal pain (5.5% vs. 1.4%) with acoramidis compared to placebo. Discontinuation rates due to adverse events were 9.3% for acoramidis and 8.5% for placebo.
Additional findings from the CMR substudy and its open-label extension, compared against a natural history cohort, are slated for presentation at the European Society of Cardiology Congress in 2026.
