Alnylam reports positive Phase III results for rare heart disease drug vutrisiran

Alnylam Pharmaceuticals saw its stock rise by 32% following positive results from the late-stage study of its RNA interference (RNAi) therapy, vutrisiran, for treating ATTR amyloidosis with cardiomyopathy (ATTR-CM). The Phase III HELIOS-B study (NCT04153149) met its primary endpoint by significantly reducing all-cause mortality and recurrent cardiovascular events in both the monotherapy and overall study groups. The monotherapy group showed a 33% reduction (hazard ratio (HR) = 0.672), while the overall population saw a 28% reduction (HR = 0.718).

Vutrisiran also demonstrated significant improvements in secondary endpoints, including 6-minute walk test (6MWT), Kansas City Cardiomyopathy Questionnaire (KCCQ), and New York Heart Association (NYHA) Class over 30 months. All-cause mortality decreased by 35% and 36% in the monotherapy and overall populations over 42 months, respectively.

The HELIOS-B study included 655 adult patients in a multicenter, double-blind trial. Vutrisiran's efficacy was consistent across key patient subgroups, including those using Pfizer’s Vyndaqel/Vyndamax concurrently. Alnylam emphasized vutrisiran's potential to become the new standard of care for ATTR-CM, complementing Pfizer's current treatment options adopted by the UK's National Health Service (NHS).