Alnylam Announces Positive Initial Phase 1b Data for Brezosiran (ALN-HTT02) Demonstrating Deep and Durable Huntingtin Lowering in Huntington’s Disease

CAMBRIDGE, Mass., October 23, 2026--Alnylam Pharmaceuticals, Inc. (Nasdaq: ALNY), the leading RNAi therapeutics company, today reported positive initial Phase 1b clinical trial results for ALN-HTT02, an investigational RNAi therapeutic in development for the treatment of Huntington’s disease, which will be developed under the International Nonproprietary Name (INN) brezosiran (bre-ZOH-sir-an). The data were presented in oral and poster presentations at the European Huntington’s Disease Network (