ALNY Q2: Revenue Beats $1.17B, TTR Guidance Cut -29%

Alnylam Pharmaceuticals (ALNY) reported second-quarter 2026 earnings on July 30, beating revenue estimates with $1.17 billion in net product revenue, up 74% year over year. AMVUTTRA (patisiran) crossed $1 billion in quarterly revenue for the first time. But the stock plunged 29% after the company cut its full-year TTR franchise guidance.

Alnylam lowered its 2026 TTR net product revenue guidance from $4.4 to $4.7 billion down to $4.2 to $4.5 billion, a $200 million reduction at the midpoint. Total net product revenue guidance fell from $4.9 to $5.3 billion to $4.7 to $5.1 billion. Management attributed the cut to normalization of second-line demand after an initial surge of patients transitioning from tafamidis, the older TTR stabilizer.

The demand shift

The guidance cut reflects a maturation phase in the ATTR-CM launch. Second-line patients, who were already diagnosed and switching from tafamidis, represented easy initial wins but are finite. First-line patients, who are treatment-naive, are the larger and more durable market but require more diagnosis and prescriber education. Management said 80% of new ATTR-CM treatment starts are now first-line, and approximately 80% of U.S. ATTR-CM patients remain untreated, framing the cut as a growth opportunity rather than a ceiling.

The competitive picture improved. Ionis and AstraZeneca’s eplontersen failed in the Phase 3 CARDIO-TTRansform trial on July 9, removing a potential TTR competitor. Generic tafamidis entry was delayed to mid-2031.

Pipeline breadth

Alnylam is expanding beyond TTR. Nucresiran, a next-generation TTR silencer achieving more than 95% knockdown with twice-yearly dosing, is in the Phase 3 TRITON-CM trial enrolling approximately 1,750 patients. Four data readouts are expected in the second half of 2026, including Phase 1 results for ALN-HTT02 in Huntington’s disease and ALN-2232 in obesity. Two new Phase 2 trials were initiated: ALN-6400 in von Willebrand disease and migalastat in Down syndrome-associated Alzheimer’s. Alnylam also announced a BeOne partnership for AMVUTTRA in China and Macau.

The obesity program entering Phase 1 data readout is notable given the frenzy around the GLP-1 market. For more on Alnylam’s RNAi platform in cardiometabolic disease, see our zilebesiran hypertension analysis.

What to watch

The stock reaction reflects investor disappointment at the growth deceleration, but the fundamental demand story has not changed. With roughly 200,000 U.S. ATTR-CM patients and 80% untreated, the market is still underpenetrated. The risk: if first-line adoption stalls, the next guidance cut could be larger. The next near-term readout is the nucresiran Phase 3 TRITON-CM interim, which could validate the next-generation TTR silencer.

Source: Alnylam Q2 2026 press release