Alnylam shares fall to $174 as TTR product demand growth slows
Key Facts
Alnylam reported third-quarter results on October 29 for the period ended September 30, as its shares fell from a close of $232.40 on October 28 to $174 the following day. The company posted total revenue of $1.458 billion, up 17% year over year, while net product revenue rose 52% to $1.292 billion. But management said it was not yet satisfied with the underlying demand growth it had observed, noting that converting increased physician outreach into treatment starts was taking longer than expected. At the same time, it expects 2026 sales of TTR products to come in near the low end of its $4.2 billion to $4.5 billion range. The company maintained its guidance for net product revenue of $4.7 billion to $5.1 billion and said it remained on track to meet its financial guidance.
Product revenue growth was driven mainly by TTR products, which generated revenue of $1.150 billion, up 59% from the third quarter of 2025. Sales of Amvuttra, the largest product in the category, rose to about $1.130 billion, up 65% year over year. The company said the increase in product revenue came mainly from Amvuttra growth on higher demand, particularly among patients with TTR amyloid cardiomyopathy in the United States, as well as growth in the number of Givlaari recipients. By contrast, Onpattro sales fell to $19.6 million, down 50% from the year-earlier period. The figures show continued expansion of the leading product, alongside management’s acknowledgment that underlying demand growth and the conversion of expanded physician outreach into treatment starts had not reached levels it found satisfactory.
In the U.S. market, TTR product revenue increased by $99 million from the second quarter. The company attributed $81 million of the increase to demand and $17 million to inventory effects, while quarterly revenue also benefited from positive gross-to-net adjustments of about $10 million. International TTR revenue rose $20 million from the previous quarter, driven mainly by continued launches of treatment for TTR amyloid cardiomyopathy in Japan, Germany and Italy, as well as the timing of orders from partner markets. The breakdown of the U.S. increase shows demand was the largest factor, with separate contributions from inventory and pricing adjustments. Elsewhere, collaboration revenue fell 80% to $71.476 million, compared with $351.742 million a year earlier, when the company recorded $300 million in revenue from a milestone payment under its collaboration with Roche in September 2025.
Diluted net income per share was $15.72 under GAAP and $16.26 on the company’s non-GAAP measure. However, GAAP net income included a tax benefit of $1.9 billion, arising mainly from the release of valuation allowances on federal and state deferred tax assets. By contrast, non-GAAP operating income was about $424.9 million, down 11% from the third quarter of the previous year. Reported earnings per share therefore reflect a substantial tax effect alongside operating performance, which recorded a year-over-year decline in adjusted operating income. Cash, cash equivalents and marketable securities totaled $3.6 billion on September 30, compared with $2.9 billion on December 31, 2025.
On the earnings call, the chief executive said the company was "not yet satisfied with the underlying demand growth we have observed." Management linked this to the longer-than-expected time it was taking to convert expanded physician outreach into treatment starts. In its guidance, the company said it expects 2026 TTR sales to be at the low end of its $4.2 billion to $4.5 billion range, while maintaining its forecast for total net product revenue of $4.7 billion to $5.1 billion. The company did not provide 2027 product revenue guidance in the announcement and said it would do so alongside its fourth-quarter and full-year results in mid-February. It also said it would provide preliminary fourth-quarter and full-year revenue figures in January.
Upcoming dates include a presentation of two-year open-label extension results from the HELIOS-B trial at the American Heart Association sessions from November 6 to 9, 2026. The company also plans to present Phase 1 data for ALN-6400 at the American Society of Hematology annual meeting from December 12 to 15. In February 2027, it intends to announce Phase 2 data for ALN-6400 in patients with hereditary hemorrhagic telangiectasia, along with Phase 1 data for ALN-2232, alongside its fourth-quarter and full-year earnings call. The company also plans to begin a placebo-controlled pivotal study of brezosiran in 2027, subject to regulatory alignment. These milestones put trial results and next year’s guidance among the main developments scheduled after the third-quarter announcement.