CAMBRIDGE, Mass. — Alnylam Pharmaceuticals has received approval from the European Commission (EC) for its RNA interference (RNAi) therapeutic AMVUTTRA® (vutrisiran) to treat adults with wild-type or hereditary transthyretin amyloidosis with cardiomyopathy (ATTR-CM), the company announced Monday. The approval marks AMVUTTRA as the first and only RNAi therapy authorized in the EU for this condition.
The decision expands AMVUTTRA’s approved use in Europe, where it was already indicated for the treatment of polyneuropathy associated with hereditary ATTR (hATTR) amyloidosis. The EC’s ruling follows earlier approvals in the United States and Brazil, signaling growing global momentum for the drug.
AMVUTTRA works by using RNA interference to suppress production of transthyretin (TTR), the protein responsible for the formation of amyloid fibrils that cause tissue damage in ATTR amyloidosis. The treatment is administered subcutaneously once every three months and can be delivered by a healthcare provider, patient, or caregiver.
The EC’s approval was based on results from the HELIOS-B Phase 3 trial, which showed that AMVUTTRA reduced all-cause mortality by 36% and significantly improved patients’ functional capacity and quality of life over 42 months. The trial enrolled a diverse patient population and demonstrated statistically significant benefits across all ten primary and secondary endpoints, including cardiovascular outcomes, heart failure symptoms, and physical health metrics.
“Approximately 100,000 people in Europe are estimated to be affected by ATTR amyloidosis, most of whom have cardiomyopathy,” said Dr. Pushkal Garg, Chief Medical Officer at Alnylam. “This approval is a critical step toward addressing this underserved population with a therapy that combines durable efficacy, a strong safety profile, and convenient quarterly dosing.”
The HELIOS-B trial results, recently published in The New England Journal of Medicine, highlighted the drug’s favorable safety profile, with adverse events similar to placebo. Most common side effects included injection site reactions and mild changes in liver enzyme levels.
Experts have praised the development as a breakthrough. “This is a milestone for patients,” said Dr. Marianna Fontana, a HELIOS-B investigator and professor of cardiology at University College London. “The trial reflected real-world practice and demonstrated that vutrisiran can meaningfully improve outcomes for people with ATTR-CM.”
Giovanni d’Alessio, President of the Amyloidosis Alliance, added that the approval offers new hope for patients often facing delayed diagnosis and limited treatment options. “This is welcome news for the amyloidosis community across Europe,” he said.
Alnylam continues to pursue regulatory submissions worldwide to expand access to vutrisiran. The therapy remains under orphan designation in the EU, which was reaffirmed by the European Medicines Agency in May 2025.
