Day One Biopharmaceuticals Reports Strong OJEMDA Revenue Growth and Expands Pipeline Through Mersana Acquisition
Key Insights
Day One Biopharmaceuticals reported preliminary 2025 OJEMDA net product revenue of $155.4 million, representing 172% year-over-year growth driven by increasing patient demand.
The company projects 2026 OJEMDA U.S. net product revenue between $225-250 million, representing 53% growth at the midpoint.
Day One completed the strategic acquisition of Mersana Therapeutics, adding Emi-Le (emiltatug ledadotin), a B7-H4 (search)-targeted ADC for adenoid cystic carcinoma (search).
Day One Biopharmaceuticals announced preliminary 2025 financial results showing significant commercial momentum for OJEMDA (tovorafenib), its targeted therapy for pediatric low-grade glioma (search), while expanding its pipeline through the strategic acquisition of Mersana Therapeutics. The company reported preliminary unaudited 2025 OJEMDA net product revenue of $155.4 million, representing 172% year-over-year growth.
Strong Commercial Performance Drives Revenue Growth
OJEMDA demonstrated robust commercial uptake throughout 2025, with fourth quarter net product revenue reaching approximately $52.8 million, representing 37% quarter-over-quarter growth compared to Q3 2025. The growth was driven by momentum in patient demand, with prescription volumes increasing to 1,394 during the fourth quarter.
"I'm thrilled by the steady uptake of OJEMDA in relapsed or refractory pLGG, and by the opportunities for future patient impact we expect from the clinical data for OJEMDA in front line pLGG and for Emi-Le and DAY301," said Jeremy Bender, Ph.D., chief executive officer of Day One.
For 2026, Day One projects OJEMDA U.S. net product revenue between $225 million and $250 million, representing 53% year-over-year growth at the midpoint. The company's focus will be on increasing persistency and driving new patient starts to support continued OJEMDA adoption as standard of care in second-line pediatric low-grade glioma (search).
Pipeline Expansion Through Strategic Acquisition
Day One recently completed the acquisition of Mersana Therapeutics, adding Emi-Le (emiltatug ledadotin) to its pipeline. Emi-Le is a novel antibody drug conjugate targeting the B7-H4 (search) protein in clinical development to treat the rare cancer adenoid cystic carcinoma (search). The company plans to deliver Phase 1 clinical data for Emi-Le by mid-2026 and progress toward registration.
The expanded pipeline also includes DAY301, a PTK7 (search)-targeted antibody drug conjugate, for which Day One expects to provide initial data from the Phase 1a clinical trial in the second half of 2026.
Clinical Development Milestones
Day One plans to complete enrollment in the pivotal Phase 3 FIREFLY-2 clinical trial in first-line pediatric low-grade glioma (search) in the first half of 2026, enabling a mid-2027 data readout and a potential approval in 2028. This represents a significant expansion opportunity for OJEMDA beyond its current indication in relapsed or refractory disease.
The company also aims to extend the OJEMDA commercial opportunity beyond the U.S. through global expansions via partnerships.
Financial Position
As of December 31, 2025, prior to the Mersana acquisition, Day One had approximately $441.1 million of cash, cash equivalents, and short-term investments. According to CEO Jeremy Bender, "Our solid financial position will continue to enable us to invest in future programs that have strong potential to become important new medicines."
Day One Biopharmaceuticals is a commercial-stage biopharmaceutical company founded to address the critical unmet need in pediatric cancer (search) therapeutic development. The company partners with leading clinical oncologists, families, and scientists to identify, acquire, and develop important targeted cancer treatments for people of all ages with life-threatening diseases.