AstraZeneca-Ionis Wainua (Eplontersen) CARDIO-TTRansform Full Data at ESC 2026 Sunday August 30; Monotherapy Subgroup HR 0.71 With No Effect on Baseline Stabilizer Patients
AstraZeneca (NASDAQ: AZN) and Ionis Pharmaceuticals (NASDAQ: IONS) presented Sunday August 30, 2026 at ESC Congress 2026 Munich the detailed subgroup analyses from the Phase 3 CARDIO-TTRansform trial of Wainua (eplontersen, an antisense oligonucleotide targeting transthyretin) in adults with transthyretin-mediated amyloid cardiomyopathy (ATTR-CM). CARDIO-TTRansform did not meet its primary composite endpoint (cardiovascular mortality plus recurrent CV events through 140 weeks) versus placebo. In the prespecified subgroup analysis, patients receiving eplontersen monotherapy achieved a nominally significant hazard ratio of 0.71 versus placebo, while patients on background TTR stabilizer therapy (tafamidis, Vyndaqel/Vyndamax) at baseline showed no treatment effect. The read-out complicates the silencer-plus-stabilizer commercial approach in ATTR-CM that Alnylam's HELIOS-B trial of vutrisiran validated with 28.2% mortality reduction and 32.8% CV event reduction on background tafamidis. AstraZeneca and Ionis will analyze the full dataset to inform next steps in the CARDIO-TTRansform program.