(RTTNews) - Ionis Pharmaceuticals Inc. (IONS) and AstraZeneca announced results from the Phase 3 CARDIO-TTRansform trial of Eplontersen in adults with transthyretin-mediated amyloid cardiomyopathy (ATTR-CM). The study did not meet its primary endpoint, a composite of cardiovascular mortality and recurrent cardiovascular events through Week 140 compared with placebo.
ATTR-CM is a progressive, life-threatening condition caused by misfolded transthyretin protein deposits in the heart, leading to heart failure and reduced quality of life. With an estimated 300,000 to 500,000 patients worldwide, earlier diagnosis and targeted therapies remain critical.
In a prespecified subgroup analysis, patients treated with Eplontersen monotherapy showed a nominally significant hazard ratio of 0.71 for reduced cardiovascular mortality and recurrent events compared to placebo. No treatment effect was observed in patients already receiving stabilizer therapy at baseline. Secondary imaging and biomarker analyses favored Eplontersen, with large and sustained reductions in transthyretin levels consistent with RNA silencer therapies.
Safety Profile Eplontersen was well tolerated, with a safety profile consistent with prior studies. Ionis CEO Brett Monia acknowledged disappointment at missing the primary endpoint but emphasized that the findings provide clarity for the evolving treatment landscape, where stabilizer use is widespread.
CARDIO-TTRansform enrolled 1,432 patients across 130 sites in 20 countries, making it the largest ATTR-CM trial to date. Participants were randomized to receive Eplontersen 45 mg or placebo every four weeks, with secondary endpoints including six-minute walk distance, quality-of-life scores, and all-cause mortality.
Ionis and AstraZeneca plan to present the full dataset at the European Society of Cardiology (ESC) Congress in August 2026.
AZN has traded between $137.22 and $212.71 over the past year. The stock closed Wednesday's trading at $189.28, down 1.99%. In pre-market trading the stock is at $174.15, down 7.97%.
The views and opinions expressed herein are the views and opinions of the author and do not necessarily reflect those of Nasdaq, Inc.