Alnylam Pharmaceuticals Inc. (ALNY) is seeking to broaden the approved indications for its RNAi therapeutic drug, Amvuttra, to include the treatment of ATTR Amyloidosis with Cardiomyopathy, and the FDA decision is due on March 23, 2025.Transthyretin-mediated (ATTR) amyloidosis is a rapidly progressive, debilitating disease caused by misfolded transthyretin (TTR) protein, which accumulates as amyloid deposits in various parts of the body, including the nerves, heart, and digestive system. There are two types of ATTR - hereditary ATTR (hATTR), which is caused by a TTR gene variant and affects approximately 50,000 people worldwide, and wild-type ATTR (wtATTR), which occurs without a TTR gene variant and affects an estimated 200,000 to 300,000 people worldwide. ATTR can cause problems like nerve damage (polyneuropathy), heart issues (cardiomyopathy), or both.Amvuttra (known generically as Vutrisiran) received FDA approval in June 2022 for the treatment of the polyneuropathy of hereditary transthyretin-mediated (hATTR) amyloidosis in adults. If approved for the expanded use, Amvuttra would become the first therapeutic approved in the U.S. to treat both the polyneuropathy manifestations of hATTR and cardiomyopathy manifestations of ATTR amyloidosis.The drug generated sales of $970 million in the full year of 2024, compared to $557.8 million in 2023.ALNY closed Wednesday’s (Mar.5, 2025) trading at $249.23, up 2.59%.