Ionis Pharmaceuticals has concluded subject enrolment in the Phase III CARDIO-TTRansform study of eplontersen for transthyretin-mediated amyloid cardiomyopathy (ATTR-CM).

An investigational antisense therapy, eplontersen is said to hinder transthyretin production and reduce cardiomyopathy progression in individuals with hereditary or wild-type ATTR-CM.

The double-blind, international, randomised, placebo-controlled cardiovascular (CV) outcome study enrolled more than 1,400 subjects to analyse eplontersen against placebo.

CV mortality and recurring CV clinical events until week 140 is the study’s primary composite endpoint.

The company anticipates reporting study data in the first half of 2025.

Ionis Pharmaceuticals executive vice-president and chief clinical development officer Eugene Schneider said: “The evaluation of eplontersen in this broad, diverse patient population will enable robust and clinically meaningful analysis of the composite endpoint of CV mortality and recurrent CV events. 

“It will also allow us to gather data from important patient subsets, including patients with or without stabiliser therapy and those with or without hereditary disease within the evolving ATTR-CM landscape.” 

Under an agreement to develop and market eplontersen, Ionis and AstraZeneca have sought regulatory approval from the US Food and Drug Administration (FDA) for the therapy to treat transthyretin-mediated amyloid polyneuropathy (ATTRv-PN).

A decision on the approval from the regulatory authority is expected on 22 December 2023. 

In April 2023, AstraZeneca and Ionis reported that the Phase III NEURO-TTRansform trial of eplontersen in hereditary ATTRv-PN patients met all co-primary endpoints and secondary endpoints.