Alnylam’s drug, vutrisiran, was approved for patients with transthyretin amyloid cardiomyopathy, or ATTR-CM, to reduce cardiovascular-related death and hospitalizations. This indication was widely expected among investors and is similar to the indications given for competing therapies.

Amvuttra’s clearance in a rare form of cardiomyopathy could help Alnylam turn a regular profit — if it can wrest control of a fast-changing market.

Amvuttra is now approved in the US to treat both cardiomyopathy and polyneuropathy manifestations of ATTR amyloidosis.