Shares of Alnylam Pharmaceuticals sank sharply in pre-open trading, falling 25.7% to $212.95 from a prior close of $286.62 after the company disclosed second-quarter 2026 results that included a revenue shortfall and a material cut to full-year guidance.
Alnylam reported Q2 revenue of $1.29 billion, below the $1.32 billion that analysts had been expecting. At the same time, the company reduced its full-year 2026 total TTR net product revenue guidance to a range of $4.2 billion to $4.5 billion, down from the previous $4.4 billion to $4.7 billion range. The midpoint of the revised guidance implies a reduction of roughly $300 million and sits well under the Wall Street consensus of approximately $5.61 billion.
Management attributed the revenue outlook adjustment to what it described as a normalization of second-line patient volumes in the ATTR-CM market after the initial wave of pent-up demand that followed Amvuttra’s launch. CEO Yvonne Greenstreet said the company lowered the outlook to reflect learnings from the early phase of the ATTR-CM launch, while reiterating confidence in the long-term potential of the franchise.
On the positive side of the report, adjusted earnings per share came in at $1.84, ahead of the $1.60 consensus estimate. The company also emphasized progress across its development programs, including the start of Phase 2 trials for ALN-6400 in von Willebrand disease and for mivelsiran targeting Down syndrome-associated Alzheimer’s disease.
The earnings shock follows a period of already-cautious analyst sentiment. JPMorgan trimmed its price target to $400 from $420 in late July, and H.C. Wainwright reduced its target to $470 from $510 in late June, moves that reflected mounting concerns about competitive pressures and the speed of the ATTR-CM ramp.
Market action outside of Alnylam was mixed to positive on the day, underscoring that the selloff was company-specific rather than market-driven. The S&P 500 was up 0.7%, the Dow Jones rose 0.5%, and the Nasdaq gained 1.5% during the same trading session.
Investors reacted strongly to the combination of a top-line miss and a guidance cut whose midpoint landed hundreds of millions of dollars below consensus. The result was the erasure of roughly a quarter of Alnylam’s market value in pre-market trading, with the stock pressured toward the lower end of its 52-week range of $262.21 to $495.55.
What this means
- Alnylam’s revenue shortfall and significant downward guidance revision drove a steep pre-market selloff, outweighing an adjusted EPS beat and reported pipeline milestones.
- Management pointed to normalization in second-line ATTR-CM patient volumes after an initial surge related to Amvuttra’s launch as the key factor behind the reduced outlook.
- Analyst targets had been trimmed in recent weeks, reflecting concerns about competitive dynamics and the pace of the ATTR-CM ramp; the results amplified those concerns among investors.
Financial highlights
- Q2 revenue: $1.29 billion (vs. $1.32 billion expected)
- Adjusted EPS: $1.84 (vs. $1.60 expected)
- Revised 2026 total TTR net product revenue guidance: $4.2 billion to $4.5 billion (previously $4.4 billion to $4.7 billion)
- Consensus full-year estimate referenced by the company: approximately $5.61 billion
- 52-week range: $262.21 - $495.55