Alnylam’s Profitability Milestone Collides With a Guidance Cut — and Investors Bolt

There is a peculiar arithmetic at work in Alnylam Pharmaceuticals’ stock right now: the company just delivered its first-ever quarterly profit, its flagship drug crossed the billion-dollar sales threshold, and its closest rival’s competing therapy failed a pivotal trial. The shares, nonetheless, have been shredded.

Over seven trading sessions, the stock lost 27.66 percent, closing Friday at EUR 177.30. That extends the year-to-date decline to 47.68 percent. The equity now sits barely above its 52-week low of EUR 172.15, set in late July, and roughly 56 percent below the October record of EUR 421.90. On the most recent trading day, the shares steadied with a gain of about 3 percent — a tentative sign of stabilization, though hardly a verdict.

The Guidance That Spoiled the Party

The trigger was the second-quarter 2026 earnings report, which on its face read like a milestone. Amvuttra, the company’s therapy for TTR amyloidosis, generated USD 1.01 billion in quarterly sales — a 106 percent jump year over year. Total product revenue reached USD 1.17 billion, and the company posted a USD 164 million GAAP net profit after a loss in the prior-year quarter. For a biotech long regarded as a bet on the future rather than a generator of current earnings, that is a genuine inflection point.

Markets, however, fixated on the accompanying revision. Alnylam trimmed its 2026 sales outlook for the TTR product family to a range of USD 4.2 billion to USD 4.5 billion, down from a prior USD 4.4 billion to USD 4.7 billion. Management attributed the change to a “normalization” of demand among second-line patients. The initial wave of patients who had been waiting for Amvuttra’s approval has now largely been treated, and that backlog — which flattered earlier quarterly comparisons — is mostly gone. Future growth will be steadier, but slower, and every new patient will have to be won rather than merely processed.

The market’s reaction was brutal. With 30-day annualized volatility running near 92 percent, short-term traders fled. Yet several analysts have kept their price targets largely intact, creating a striking disconnect: the average target still stands at EUR 374.50, implying upside of roughly 105 to 111 percent from current levels depending on the reference close. That gap is not a rounding error — it reflects a fundamental disagreement about what the company is worth in a market that no longer treats it as a monopoly story.

Should investors sell immediately? Or is it worth buying Alnylam?

Competition Fades, Even as the Narrative Shifts

One development complicates the bearish narrative. Ionis Pharmaceuticals, the most significant rival in the RNAi space, recently conceded that its candidate Wainua failed the CARDIO-TTRansform study. That leaves Alnylam’s TTR franchise — which generated USD 1.03 billion in the second quarter, up 89 percent year over year — effectively without a direct competitor in the ATTR-CM and ATTR-PN markets, apart from Pfizer.

The company is also no longer a one-product operation. First data for the Huntington’s disease candidate ALN-HTT02 are expected in October 2026, and Mivelsiran is already in Phase 2 development. Management even raised its guidance for collaboration and license revenue to USD 575 million to USD 625 million, while the balance sheet holds USD 3.3 billion in cash. At a market capitalization of roughly EUR 23.8 billion, the company is profitable, dominant in its niche, and not remotely in distress.

A Chart That Screams Oversold

Technically, the stock is flashing extreme readings. The 14-day RSI has fallen to 23.0 — deeper into oversold territory than the 26.4 level seen in the other recent assessment — and the shares trade 42.30 percent below their 200-day moving average. Such deviations rarely persist without some kind of counter-move. Institutional investors, including Janus Henderson, have added to positions during the sell-off.

The risk, of course, is that oversold conditions in biotech can persist for weeks when the underlying narrative shifts. The story here has changed from a monopoly to a defense of market share, and that repricing does not resolve itself on a single technical signal. The question now is whether the market is treating a growth normalization as a business-model collapse — or whether the lower guidance is the first honest acknowledgment of a more competitive, more mature phase for a company that investors once valued as a perpetual growth machine. The answer will come not from the RSI, but from how many new patients Alnylam can actually win in a market that just got quieter on the competition front — and harder on the growth expectations front.