AstraZeneca and Ionis Announce Thursday July 9 That the Phase 3 CARDIO-TTRansform Trial of Wainua (Eplontersen, Antisense Oligonucleotide Nucleic-Acid Therapeutic) in Adults with Transthyretin-Mediated Amyloid Cardiomyopathy (ATTR-CM) Missed Its Primary Composite Efficacy Endpoint of Cardiovascular Mortality and Recurrent Cardiovascular Events Through 140 Weeks Compared With Placebo; Prespecified Monotherapy Subgroup Analysis Showed Nominally Significant Composite-Event Reduction; Full Results to Be Presented at ESC Congress in August 2026
AstraZeneca and Ionis Pharmaceuticals announced Thursday July 9, 2026 that the Phase 3 CARDIO-TTRansform trial of Wainua (eplontersen) did not meet its primary efficacy endpoint in adults with transthyretin-mediated amyloid cardiomyopathy (ATTR-CM). The trial enrolled over 1,400 patients and was the largest Phase 3 study conducted in the ATTR-CM population to date; the primary endpoint was a composite of cardiovascular mortality and recurrent CV clinical events through 140 weeks compared with placebo. Prespecified subgroup analyses showed nominally significant reductions in composite events with eplontersen monotherapy versus placebo, while patients also receiving a baseline TTR stabilizer showed no incremental effect. Eplontersen is an antisense oligonucleotide (a nucleic-acid therapeutic modality distinct from peptides but adjacent in the metabolic-and-cardiovascular therapeutic territory this site tracks); the drug is already FDA-approved as Wainua for hereditary transthyretin amyloidosis polyneuropathy. Full CARDIO-TTRansform results will be presented at the European Society of Cardiology (ESC) Congress in August 2026. AstraZeneca and Ionis shares fell on the readout.