Alnylam (ALNY) Q3 2026 Earnings: US AMVUTTRA Demand Growth Slows

Alnylam Pharmaceuticals (ALNY) Q3 2026 earnings show slower US demand growth for AMVUTTRA alongside stronger profit conversion. On October 29, 2026, the company released its results for the quarter ended September 30 in an earnings release and quarterly report and held an earnings call [1][2][3]. The slowdown in new US patients weakens the growth picture, while operating margin came in better than the prior quarter.

Three questions framed this quarter. The first was whether first-line US patients could support the TTR revenue guidance that Alnylam cut in July. The second was whether revenue growth could still turn into operating profit after AMVUTTRA crossed Sanofi's top royalty tier. The third was whether the raised collaboration and royalty guidance rested on recurring revenue. In Q3, sequential US demand growth fell to $81 million, and the company now expects full-year TTR revenue at the low end of guidance. The non-GAAP operating margin rose to 29.1%, but part of that gain reflects expense timing and other items that will not repeat. Collaboration and royalty revenue of $166 million kept pace with guidance, supported mainly by Leqvio royalties [1][2]. Taken together, the growth engine has stepped down, while profit and cash generation continue to improve.

Alnylam pioneered RNA interference (RNAi) medicines. Its core product, AMVUTTRA, is a TTR silencer injected once every quarter to treat transthyretin amyloidosis with cardiomyopathy (ATTR-CM) and with polyneuropathy. Revenue comes from product sales, partner reimbursements and milestones, and royalties on drugs such as Leqvio. The largest variable cost is the tiered royalty Alnylam pays Sanofi on annual AMVUTTRA sales, with a top rate of 30% [4].

US AMVUTTRA demand growth slowed, leaving full-year TTR at the low end

Underlying US demand grew much less than in the second quarter. US TTR revenue rose $99 million from Q2, made up of $81 million from demand, $17 million from channel inventory and about $10 million from a one-time gross-to-net adjustment [1]. In Q2, the demand increase was $129 million [5]. The CFO said the inventory and gross-to-net items do not measure underlying demand, and that US inventory and price will both weigh on reported growth in Q4 [2].

Management attributed the slowdown to slow conversion of new prescribers. The company said its expanded sales force has increased physician engagement but has not yet produced more patient starts. Newer physicians see fewer cardiomyopathy patients, know the disease less well and have entrenched habits, and non-clinical hurdles such as prior authorization take time to overcome [2]. Cumulative new prescribers passed 2,000, and the new-to-brand prescription share stayed stable above 30%, which means AMVUTTRA's share of new starts did not expand. The company did not repeat its first-line share of new starts this quarter [2].

Guidance and the payer backdrop also tightened. Alnylam reiterated its $4.2 billion to $4.5 billion TTR guidance but expects to land at the low end, said growth will not accelerate in Q4, and assumes no material revenue contribution from the sales force expansion in its 2026 outlook [2]. With nine-month TTR revenue of $3.09 billion, the low end implies Q4 TTR revenue of about $1.109 billion, below Q3's $1.15 billion [1][3]. UnitedHealth tightened first-line AMVUTTRA access in Medicare Advantage on October 1. If finalized, a CMS 340B rule would take effect on January 1, 2027; the company said it could cause Q4 ordering volatility and moved its 2027 guidance to February [2]. Outside the US, AMVUTTRA revenue reached $222 million, with sequential growth from ATTR-CM launches in Japan, Germany and Italy partly offsetting the US slowdown [1][3].

Operating margin rose to 29.1% despite the higher royalty tier

Profit conversion improved from the second quarter. Non-GAAP operating income was $425 million and the operating margin was 29.1%, compared with $318 million and 24.6% in Q2 [1][5]. Cost of goods sold equaled 28.0% of net product revenues, which the company attributed to a higher blended AMVUTTRA royalty rate, consistent with the tiered contract [1].

Part of the improvement will not repeat. Non-GAAP R&D and SG&A expenses were $671 million, below the quarterly pace implied by full-year guidance of $2.7 billion to $2.8 billion, so Q4 spending needs to rise to roughly $737 million to $837 million [1]. Inventory, the one-time gross-to-net adjustment and Regeneron collaboration revenue of $32 million, for which the company gave no driver, also lifted Q3 profit [1].

Cash continued to build. Operating cash flow was $738 million for the first nine months, with capital expenditures of $126 million [3]. Cash, cash equivalents and marketable securities were $3.6 billion on September 30 [1]. GAAP net income of $2.2 billion came mainly from an approximately $1.9 billion release of the allowance on US deferred tax assets, a one-time non-cash benefit [1].

Conclusion

This report lowers the outlook for Alnylam's growth rate, while profit and cash generation keep improving. The US demand slowdown has already happened, the company says Q4 will not accelerate, and the case that the larger sales force will convert into patient starts rests only on management's explanation so far. The expense-timing part of the margin gain will reverse in Q4, and the royalty tiers reset each January. The 2027 guidance in February, Q4 US demand growth and the actual effect of the 340B rule on net price and volume will show whether this assessment strengthens or eases.

Sources

[1] ALNY Q3 2026 8-K filed 2026-10-29 · 2026-10-29 · Alnylam 8-K earnings release (Exhibit 99.1) · https://www.sec.gov/Archives/edgar/data/1178670/000117867026000074/alny2026q3earningsrelease.htm [2] ALNY Q3 2026 earnings call 2026-10-29 · 2026-10-29 · Alnylam earnings call · https://gateway.drillr.ai/mcp/private [3] ALNY Q3 2026 10-Q filed 2026-10-29 · 2026-10-29 · Alnylam 10-Q quarterly report · https://www.sec.gov/Archives/edgar/data/1178670/000117867026000076/alny-20260930.htm [4] ALNY FY2025 10-K filed 2026-02-12 · 2026-02-12 · Alnylam 10-K annual report · https://www.sec.gov/Archives/edgar/data/1178670/000162828026007497/alny-20251231.htm [5] ALNY Q2 2026 8-K filed 2026-07-30 · 2026-07-30 · Alnylam 8-K earnings release · https://www.sec.gov/Archives/edgar/data/1178670/000117867026000060/alny2026q2earningsrelease.htm