Alnylam Pharmaceuticals shared that the FDA has declined to approve the expanded use of the company's RNA interference therapy for a rare and fatal heart disease.
In a surprise move, the agency issued a CRL in response to Massachusetts-based Alnylam's supplemental NDA for patisiran for the treatment of the cardiomyopathy of transthyretin-mediated (ATTR) amyloidosis, citing insufficient evidence of clinical meaningfulness.
The decision follows a favorable vote from an FDA advisory committee less than a month ago. In mid-September, the Cardiovascular and Renal Drugs Advisory Committee voted 9-3 in favor of patisiran, finding that the siRNA therapeutic’s benefits outweigh its risks for cardiomyopathy of ATTR amyloidosis.
The drug, branded Onpattro, was first approved in 2018 making it the first medicine specifically cleared to treat a rare and deadly disease called hereditary transthyretin amyloidosis (hATTR). The decision marked the first-ever approval for a medicine that uses RNA interference (RNAi), a method cells can use to silence a gene before it makes a harmful protein.
With positive results from a phase 3 study where Onpattro met the primary endpoint as well as the first secondary endpoint at month 12, demonstrating a significant difference compared to placebo in functional capacity and health status and quality of life, Alnylam had hoped to nab the ATTR amyloidosis indication.
Now, as a result of the CRL, the company will no longer pursue an expanded Onpattro indication in the U.S. Instead, Alnylam will focus on vutrisiran, its investigational RNAi therapeutic subcutaneously administered once every three months, currently in phase 3 development for the treatment of the cardiomyopathy of ATTR amyloidosis.