Alnylam completes enrollment of HELIOS-A phase III study of vutrisiran for the treatment of hATTR amyloidosis with polyneuropathy.

Alnylam Pharmaceuticals, Inc. announced that it has achieved full enrollment in its HELIOS-A Phase III study of vutrisiran an investigational RNAi therapeutic in development for the treatment of ATTR amyloidosis. The study was designed to enroll 160 patients with hereditary ATTR (hATTR) amyloidosis with polyneuropathy across 68 sites in 22 countries. Alnylam is on track to report topline results from HELIOS-A in early 2021. HELIOS-A is a Phase III global, randomized, open-label study to evaluate the efficacy and safety of vutrisiran in patients with hATTR amyloidosis with polyneuropathy. The trial randomized patients 3:1 to receive either 25mg of vutrisiran subcutaneously once every 12 weeks or 0.3 mg/kg of patisiran intravenously once every three weeks. For most endpoints, results from the vutrisiran arm will be compared to results from the placebo arm of the landmark APOLLO Phase III study, which evaluated the efficacy and safety of patisiran in people with hATTR amyloidosis with polyneuropathy. The co-primary endpoints of HELIOS-A are the change from baseline in the modified Neurologic Impairment Score +7 (mNIS+7) and in the Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QoL-DN) score, at 9 months. Secondary endpoints include the change from baseline in key clinical evaluations including the timed 10-meter walk test (10-MWT), modified body mass index (mBMI), and Rasch-built Overall Disability Scale (R-ODS). The percent reduction in serum transthyretin (TTR) levels in the vutrisiran arm will be compared to the within-study patisiran arm. Additional exploratory endpoints will be assessed to determine the effect of vutrisiran on other aspects of the multisystem nature of this disease, including manifestations of cardiac amyloid involvement.