Alnylam (ALNY) Q3 2026 earnings review
Alnylam's heart drug hits its plan, but US demand slows
Alnylam, a maker of gene-silencing medicines for rare diseases, kept its full-year sales plan on track while underlying US demand growth cooled. Total product sales jumped 52% from a year ago to $1,292 million, and chief executive Yvonne Greenstreet kept every full-year target unchanged. By our math, total revenue grew 54% after stripping out a one-time Roche milestone payment from last year.
| Revenue excluding last year's Roche milestone | +54% reported revenue: +17% to $1,458M |
|---|---|
| TTR drug sales | $1,150M +59% from a year ago; +$120M from Q2 |
| Product gross margin | 72.0% 76.8% a year ago on higher Sanofi royalties |
| Full-year 2026 outlook | Unchanged middle of the product sales range: 64% growth |
⚖️ Verdict: ⚪ Neutral
The story is unchanged because heart-drug sales matched the lowered pace management set three months ago, without proving whether demand will speed up or slow down next year. Early Huntington's disease trial data succeeded, but US heart-drug demand added $81 million after adding $129 million last quarter, with stocking and rebate adjustments filling the gap. Meanwhile, rising Sanofi royalties cut product gross margin by nearly 5 percentage points, and the company expanded its next-generation heart trial a second time.
The question now is whether newly diagnosed heart patients can keep TTR sales growing by more than $100 million a quarter without help from inventory stocking. If first-line adoption is still building, fourth-quarter demand will bounce back; if the initial wave is fading, sequential growth will fall short. Fourth-quarter US demand numbers and the 2027 outlook in February will settle it.
🐂 Bull Case
Heart-Disease Drug Sales Match the Reset Plan
Alnylam sells two medicines, Amvuttra and Onpattro, for transthyretin amyloidosis (TTR), a disease where faulty proteins build up in the heart and nerves. Chief executive Yvonne Greenstreet said the company remains focused on commercial investments to "bring AMVUTTRA to more patients with ATTR amyloidosis". Last quarter management cut its full-year TTR sales plan by $200 million.
Third-quarter TTR sales reached $1,150 million, up 59% from a year ago and up $120 million from the second quarter. International TTR sales added $20 million from last quarter because of heart-disease launches in Japan, Germany and Italy. That $120 million quarterly gain matched the $116 million pace that the lowered full-year outlook required by our math.
What to watch: fourth-quarter TTR product sales when full-year results arrive in February 2027. By our math, the middle of the full-year outlook requires $1,259 million in the fourth quarter, or another $109 million gain from this quarter, which would prove the reset growth pace is holding.
Huntington's Drug Clears Its First Human Test
Alnylam is trying to prove its gene-silencing technology works in the brain so it does not rely only on liver-targeted drugs. This quarter the biotech group presented initial Phase 1 trial results for brezosiran, an experimental medicine for Huntington's disease developed with partner Regeneron. Patients in the highest dose group saw mutant huntingtin protein in their spinal fluid drop 60% to 64% after three months.
The company reported no dose-related brain swelling or nerve damage markers, and it said the effect lasted long enough to support dosing twice a year. Management plans to start a late-stage trial in 2027 after speaking with regulators, and also completed Phase 2 enrollment for mivelsiran in cerebral amyloid angiopathy, a brain blood-vessel disorder.
What to watch: Phase 2 bleeding-disorder results for ALN-6400 and Phase 1 obesity data for ALN-2232 in February 2027. Positive readouts alongside the fourth-quarter report would broaden the clinical pipeline before the Huntington's study begins.
Positives this quarter didn't test
Four standing growth drivers from prior quarters received no new figures in the third-quarter earnings release because management usually updates them on the conference call.
- First-line patient share: last reported at roughly 80% of new treatment starts; the call transcript will show whether that share held.
- Doctor adoption: last reported at over 1,700 new prescribers since the heart-disease launch, covering about one-third of target doctors.
- Artificial intelligence screening tools: no update on patient identification from hospital partnerships with Viz.ai, Komodo Health and California clinics.
- China partnership and rival setbacks: no timeline update on the BeOne distribution deal or market share gains after a rival silencer failed its trial.
🐻 Bear Case
US Heart-Drug Demand Growth Slowed in Q3
Alnylam relies on newly diagnosed US heart-disease patients to drive growth now that the early wave of patients switching from older pills has faded. "Our third quarter results reflect the continued growth of our TTR franchise and advancement of key programs with the potential for transformative patient impact," chief executive Yvonne Greenstreet said. Total US TTR sales rose by $99 million from the second quarter.
- US TTR demand growth: $81 million from last quarter, down from $129 million of demand growth in the second quarter
- US wholesaler inventory change: a $17 million boost in the third quarter, after a $21 million drag in the second quarter
- US pricing adjustments: a $10 million benefit from rebate estimates, which helped offset ongoing annual price declines
The headline $99 million US increase looked steady next to the second quarter's $106 million reported gain, but stocking and rebate adjustments supplied $27 million of it. Underlying US demand growth slowed by more than a third from the prior quarter, which raises the risk that first-line patient starts are also cooling after an initial wave.
What to watch: the fourth-quarter US demand breakdown between patient volume, inventory and rebate adjustments. Another slowdown in underlying demand without an inventory boost would leave TTR sales below the middle of the full-year plan.
Higher Royalties Cut the Product Gross Margin
Alnylam pays tiered royalties to Sanofi on global sales of Amvuttra, and the top 30% royalty rate kicks in once annual sales pass $1.5 billion. As Amvuttra sales rose 65% from a year ago to $1,130 million this quarter, cost of goods sold—the cost of making the drugs and paying royalties—jumped from 23.2% to 28.0% of product sales.
The company attributed the 4.8 percentage point product gross margin drop to higher Amvuttra volume and "an associated increase in the blended royalty rate payable on net sales of AMVUTTRA". Operating profit excluding one-offs fell 11% from a year ago to $425 million because last year included a $300 million milestone payment from Roche, while research and development spending rose 0.9 percentage points of revenue.
What to watch: fourth-quarter cost of goods sold as a share of product sales. Because cumulative annual sales of Amvuttra are at their highest point in the fourth quarter, the royalty drag on gross margin will peak at year-end.
Next-Generation Heart Trial Expands a Second Time
Alnylam's long-term profit plan depends on nucresiran, a twice-yearly successor to Amvuttra that carries no Sanofi royalty and is aimed at a 2030 heart-disease launch. In the first quarter management expanded its Phase 3 TRITON-CM trial from 1,250 to 1,750 patients. Today the drugmaker expanded the trial again to about 2,250 patients.
The company said the extra 500 slots are "enriched for patients with early disease who are expected to experience greatest benefit and ensures adequate study power under conservative estimates of outcome event rates". Enrolling healthier patients means fewer heart attacks and deaths occur per hundred patients, so the trial needs a larger group to prove the drug works, though management still targets a 2030 launch.
What to watch: completion of enrollment in the expanded 2,250-patient TRITON-CM study. Because the trial finishes only after a set number of patient heart events occur, slower event rates among healthier patients could delay the final readout past 2030.
Risks this quarter didn't answer
Several standing legal, concentration and pricing risks received no update in the third-quarter earnings release.
- Federal pricing subpoena: no update in the release on the October 2025 US Attorney subpoena covering government price reporting and distributor discounts; the quarterly 10-Q filing will carry the legal footnote.
- Patient counts and mix: management again provided dollar changes rather than total patient numbers or the split between first-line and second-line patients.
- Single-drug reliance: Amvuttra generated 87.5% of net product sales this quarter, leaving the business tied to one medicine.
- International price concessions and generic rivals: no new detail on overseas price cuts for heart-disease launches or insurance restrictions from generic tafamidis in Europe.
👓 Other Themes
One-Time Tax Benefit Lifted Net Profit
Alnylam recorded a $1.87 billion income tax benefit in the third quarter after releasing valuation allowances on US federal and state deferred tax assets, a move management flagged as possible last quarter. That non-cash accounting credit lifted reported net profit to $2.17 billion and profit per share excluding one-offs to $16.26; without the tax credit, profit per share excluding one-offs was $2.68 by our math.
💲 Other KPIs
Cash and marketable debt securities rose by $279 million from last quarter and by $679 million, or 23.3%, from the end of 2025. The company said operating cash inflows drove the increase, even after it funded expanding Phase 3 clinical trials in heart disease and high blood pressure.
Uncollected customer bills rose 18.9% from the second quarter, outpacing the 12.9% quarterly rise in total revenue and the 10.2% rise in product sales. Accounts receivable are up 12.5% from a year ago, when the total included a $300 million milestone receivable from Roche.
Interest expense rose 25.1% from a year ago. That included $58 million on the liability from selling future Leqvio royalties and $23 million on development funding liabilities for vutrisiran and zilebesiran. Cash payments on those liabilities totaled $69 million inside operating cash flow this quarter.
🔮 Guidance
Unchanged. The plan calls for 57% to 71% product sales growth, or 64.1% at the middle of the range. By our math, that leaves $1,400 million for the fourth quarter, or 40.7% growth from a year ago as the company laps last year's steep heart-disease launch.
Unchanged. After cutting this range by $200 million last quarter, Alnylam kept the midpoint at $4,350 million, or 74.9% growth for the year. By our math, hitting the midpoint requires $1,259 million in the fourth quarter, up 46.7% from a year ago and up $109 million from this quarter.
Unchanged. Sales of rare-disease drugs Givlaari and Oxlumo are planned to grow 10.0% at the $550 million midpoint. After $410 million in the first nine months, the midpoint leaves $140 million for the fourth quarter by our math, or 2.9% growth from a year ago.
Unchanged. The $600 million midpoint is down 17.5% from 2025 because last year included a $300 million Roche milestone. By our math, after $416 million in the first nine months, the midpoint requires $184 million in the fourth quarter, up from $166 million this quarter ahead of a November FDA decision on partner drug cemdisiran.
Unchanged. Research and administrative costs excluding stock-based pay are set to rise 26.0% at the $2,750 million midpoint. By our math, that leaves $787 million for the fourth quarter, up 25.7% from a year ago as Phase 3 trials expand.
❓ Key Questions
Why did US heart-drug demand growth slow in Q3?
US TTR demand added $81 million this quarter, down from $129 million in the second quarter, while inventory and rebate adjustments added $27 million. Investors need to know whether first-line patient starts slowed or if seasonal summer doctor visits held back volume.
Why did TRITON-CM need 500 more patients now?
Alnylam raised target enrollment for its next-generation heart study from 1,750 to 2,250 patients after already expanding it in the first quarter. Did blinded trial tracking show fewer heart events than planned, and could slower event rates push the readout past 2030?
Does Q4 partner revenue depend on cemdisiran approval?
By our math, the full-year partner and royalty outlook requires $184 million in the fourth quarter, up from $166 million in the third quarter. How much of that fourth-quarter figure comes from a Regeneron milestone if the FDA approves cemdisiran in November?
What are the latest prescriber and first-line start numbers?
The earnings release omitted the share of new starts coming from first-line patients and the total number of doctors prescribing Amvuttra. Because management pointed to those two figures as its main growth drivers last quarter, their third-quarter readings are essential.