AstraZeneca's (LSE:AZN) Phase III CARDIO-TTRansform trial of Wainua (eplontersen), developed jointly with Ionis, failed to meet its primary efficacy endpoint in patients with transthyretin-mediated amyloid cardiomyopathy (ATTR-CM).
The trial, the largest enrolled ATTR-CM study to date with 1,432 participants across 20 countries, tested whether adding Wainua to standard of care reduced a composite of cardiovascular mortality and recurrent cardiovascular events over 140 weeks versus placebo.
The result was complicated by high background use of stabiliser therapy: 57% of patients in each arm were on a stabiliser at baseline, with a further 24% initiating one during the trial.
In a prespecified subgroup of patients receiving Wainua without a stabiliser, fewer primary composite events were observed and the result was nominally significant, but no treatment effect was seen in those on stabiliser therapy at baseline.
Wainua was generally well tolerated, with a safety profile consistent with prior results.
"Although the trial did not meet its primary objective, we believe the results support greater scientific understanding of treatment approaches for the hundreds of thousands of patients worldwide suffering from this progressive and often fatal condition," said Sharon Barr, Executive Vice President of BioPharmaceuticals R&D.
Wainua is already approved for hereditary transthyretin-mediated amyloid polyneuropathy in over 20 countries.
