Ionis revenue doubles on drug sales, partnership windfall
The biotech raised full-year guidance after commercial revenue rose 42% and R&D revenue more than doubled.
The RNA-focused drug developer Ionis Pharmaceuticals (IONS) reported first-quarter revenue that nearly doubled year-over-year, propelled by accelerating sales of its commercialized medicines and a surge in partnership milestone payments.
The quarter marked a sharp inflection for the company, which had seen commercial revenue growth slow to single digits in late 2025. Revenue growth reaccelerated to 87% in the period, up from 42% in the same quarter a year earlier, as Ionis’s first two internally launched drugs gained traction and research collaborations delivered outsized payments.
Total revenue reached $246 million, up from $132 million in the prior-year quarter. Earnings per share swung to a non-GAAP loss of $0.48 a share from a loss of $0.77 a share in the first quarter of 2025.
Commercial revenue rose 42% to $108 million, driven by TRYNGOLZA and DAWNZERA, which together generated $43 million in U.S. net product sales—up from $6 million in the year-ago period. TRYNGOLZA U.S. net sales climbed to $27 million, though the company noted a decline in net price. DAWNZERA, launched in late 2025, contributed $16 million, a 125% sequential increase from the fourth quarter. Research and development revenue surged to $138 million from $56 million, including $95 million in milestone payments from partners.
Operating expenses increased to $364 million from $278 million, reflecting investments in commercialization and launch preparations for olezarsen and zilganersen. Despite the higher spending, the non-GAAP operating loss narrowed to $75 million from $117 million, as revenue growth outpaced cost increases.
The company raised its full-year guidance, increasing total revenue expectations by $75 million to a range of $875–900 million and reducing the projected non-GAAP operating loss by the same amount to $425–475 million. Ionis also lifted its peak net sales forecast for olezarsen in severe hypertriglyceridemia to more than $3 billion from more than $2 billion.
Regulatory momentum added to the quarter’s progress. The FDA accepted three new drug applications for Priority Review: bepirovirsen for chronic hepatitis B, with a decision due October 26; zilganersen for Alexander disease, with a September 22 target date; and an olezarsen supplemental application for severe hypertriglyceridemia, with a June 30 PDUFA date. Phase 3 trials of bepirovirsen showed a 19% functional cure rate in the overall study population, rising to 26% in patients with lower viral activity.
Cash and short-term investments fell to $1.9 billion as of March 31 from $2.7 billion at year-end, primarily due to the $633 million maturity of 0% convertible notes on April 1.