Alnylam Pharmaceuticals has completed patient enrolment in the Phase III HELIOS-A clinical trial of vutrisiran for the treatment of hereditary transthyretin (hATTR) amyloidosis.
ATTR amyloidosis is a rare, debilitating disease that develops due to the accumulation of misfolded TTR proteins as amyloid deposits in body tissues, including the heart and nerves.
Vutrisiran is an investigational RNAi therapeutic intended to silence specific messenger RNA and prevent the production of wild-type and mutant transthyretin (TTR) protein. It is being developed to treat hATTR and also wild-type (wtATTR) amyloidosis.
The global, randomised, open-label HELIOS-A study is being conducted to assess the safety and efficacy of vutrisiran in 160 patients suffering from hATTR amyloidosis with polyneuropathy at 68 sites across 22 countries.
Participants will be treated with 25mg subcutaneous vutrisiran once every 12 weeks or 0.3mg/kg intravenous patisiran once every three weeks.
The trial’s co-primary endpoints are the change in the modified Neurologic Impairment Score +7 (mNIS+7) and the Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QoL-DN) score from baseline to nine months.
Secondary endpoints include ten-metre walk test, modified body mass index, and Rasch-built Overall Disability Scale. Other exploratory endpoints aim to monitor the multisystem nature of the disease.
Data on most of the endpoints will compare Alnylam’s drug to the placebo results from the Phase III APOLLO study of patisiran in hATTR amyloidosis with polyneuropathy.
Top-line results from the Phase III HELIOS-A study are expected next year.
Alnylam Pharmaceuticals Vutrisiran Program lead Rena Denoncourt said: “We are committed to developing multiple therapeutic options for this progressive, life-threatening and multisystem disease, and believe that vutrisiran, as a low-dose, once-quarterly, subcutaneously administered investigational therapeutic, can be an attractive option for patients.”
Vutrisiran is also being studied in the Phase III HELIOS-B trial in patients with ATTR amyloidosis with cardiomyopathy.
In September last year, Alnylam initiated the Phase III APOLLO-B study of patisiran in adults with ATTR amyloidosis with cardiomyopathy.