Ionis, AstraZeneca Stumble in ATTR-CM Trial as Rivals Stand to Gain - Ionis Pharmaceuticals (NASDAQ:IONS)

Ionis Pharmaceuticals Inc.

(NASDAQ:IONS) and partner AstraZeneca Plc (NYSE:AZN) said on Thursday that their Phase 3 CARDIO-TTRansform study of eplontersen for transthyretin-mediated amyloid cardiomyopathy (ATTR-CM) failed to meet its primary efficacy endpoint. • Ionis Pharmaceuticals stock is taking a hit today.

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In patients receiving contemporary standard of care, including a majority treated with a transthyretin stabilizer, adding eplontersen did not significantly reduce the combined risk of cardiovascular mortality and recurrent cardiovascular clinical events through Week 140 versus placebo.

At baseline, 57% of participants in both treatment groups were receiving stabilizer therapy, while another 24% in each arm started a stabilizer during the study.