Alnylam Cuts Amvuttra Sales Guidance as Second-Line Demand Normalizes, Hitting Stock

Alnylam Pharmaceuticals has cut its 2026 sales guidance for its flagship ATTR drug Amvuttra after demand growth normalizes following an initial surge driven by pent-up patient demand, sending its stock down nearly 30% to a new 52-week low; second-quarter 2026 Amvuttra sales reached about $1.01–1.03 billion, topping $1 billion for the first time but missing analyst expectations by roughly 4%, and the company has lowered its full‑year TTR net product revenue guidance from $4.4–4.7 billion to $4.2–4.5 billion, a $200 million reduction at the midpoint, citing moderated second‑line usage in the U.S. ATTR‑CM market while still projecting around 75% year‑over‑year growth and maintaining confidence in the long‑term ATTR franchise and broader pipeline; the stock selloff erased roughly $12 billion in market value, with shares trading around $200–211 versus a prior close near $286, raising investor concerns about demand sustainability and competition despite raised expectations for collaboration and royalty revenues.

newssourcesusedcount: 10, mainsummarysentences: 2, importancerank: 1, likelyinteresttags:
["biotech", "pharma", "earnings", "guidancecut", "stockmove", "clinical_race"]