Day One Biopharmaceuticals (NASDAQ:DAWN) executives highlighted accelerating commercial momentum for OJEMDA and outlined multiple upcoming clinical catalysts during a fireside chat at TD Cowen’s 46th Annual Healthcare Conference.
Charles York, the company’s CFO and COO, said 2025 marked a “fantastic year” for Day One as it delivered its first full year of OJEMDA sales following approval in pediatric low-grade glioma. York reported that the company finished 2025 with more than $155 million in revenue, representing over 170% year-over-year growth. He added that results strengthened in the back half of the year, with fourth-quarter revenue of more than $52 million, up 37% quarter-over-quarter.
Launch metrics: new patient starts and persistence
On persistence, York said the company continues to see approximately 17 months of therapy duration on a mean basis and 19 months on a median basis in the commercial setting. He noted that because OJEMDA has been in the commercial market for a relatively short time—about 20 months by the end of the year—the company expects the mean duration to increase as more patients remain on therapy longer.
Mike Vasconcelles, head of R&D, said increasing physician familiarity is shifting usage toward the second-line setting. He said that in the FIREFLY-1 pivotal study, patients had a median of three prior therapies, while more recent commercial experience shows increasing use in second line. Vasconcelles added that Day One’s teams have identified practical factors that can affect persistence, including early management of rash—described as manageable but potentially disruptive for adolescents—and the role of dose reductions. York added that the company has observed greater persistence when patients are dose-reduced and noted that the company’s pricing is flat in a way that makes dose reductions financially equivalent from its perspective.
Longer-term data and upcoming publication
Vasconcelles pointed to data presented at ASCO addressing concerns about potential effects on children’s normal growth. He said the company showed that “virtually all” patients demonstrate catch-up growth or a normalized growth velocity for their age after coming off therapy, which he described as reassuring for physicians and families.
He also cited longer-term FIREFLY-1 follow-up data presented at a neuro-oncology meeting at the end of 2025, emphasizing measures such as time to next therapy after OJEMDA and the treatment-free interval. Vasconcelles said the median time to next therapy was “pushing almost 43 months” and that the treatment-free interval off therapy was over a year. He said nearly 80% of children remained off therapy for a year after completing a full course of OJEMDA, compared with physician expectations that having even half of patients off therapy for a year would be meaningful.
Vasconcelles said the company has submitted a paper to a peer-reviewed journal and hopes the publication will be available by mid-year, which he framed as part of an intentional cadence of data release intended to support physician education.
2026 revenue guidance and growth drivers
York said Day One is guiding to $225 million to $250 million in net product revenue for 2026. He described the midpoint as approximately 50% year-over-year growth and said the difference between the low and high ends of the range reflects execution on the same operational levers discussed during the session—namely growing new patient starts and improving persistence through additional data and physician education.
Frontline opportunity and trial progress
Vasconcelles discussed the company’s frontline study in pediatric low-grade glioma, describing it as the largest randomized controlled trial ever undertaken in the disease and comparing tovorafenib with investigator’s choice chemotherapy. He said Day One has a “high expectation” of success given the relapsed setting data already generated.
He also highlighted observations that the company has not seen acquired mutations following exposure to certain therapies in either clinical experience or preclinical models. As support for potential re-treatment, he said FIREFLY-1 includes patients who came off therapy, entered a treatment-free observation period, and were then retreated with OJEMDA, tolerating it well and achieving antitumor responses. Vasconcelles said the frontline study is designed for “treat to progression,” differing from FIREFLY-1’s approximate 26-cycle (about two-year) structure, and he argued that treat-to-progression experience may support longer-term use patterns over time.
Asked about the scale of the frontline opportunity, Vasconcelles said the number of U.S. patients who could be eligible for OJEMDA in frontline, if supported by data and labeling, is “roughly the same” as those eligible in second or subsequent lines.
Pipeline updates: DAY301 and Emi-Le
Beyond OJEMDA, York and Vasconcelles outlined a busy year for pipeline readouts. York said Day One expects mid-year data for Emi-Le, a B7-H4-targeted antibody-drug conjugate (ADC) being developed in adenoid cystic carcinoma (ACC). He also said the company anticipates first clinical data in the back half of 2026 for DAY301, a PTK7-targeted ADC that has been enrolling patients for about a year.
- DAY301 (PTK7 ADC): York said the program was in-licensed in mid-2024 and dosed its first patient in the back half of 2024. Vasconcelles said the company has advanced through dose escalation and is seeing antitumor signal even before reaching a recommended Phase 2 dose for expansion. He said the end-of-year update is expected to support decisions around “histology-specific or tumor-specific expansion cohorts,” including discussion of tolerability, the specificity of antitumor signal, and pharmacokinetics and potential pharmacodynamic markers.
- Emi-Le (B7-H4 ADC): York said the company’s investment thesis is anchored on ACC, citing confidence in a relatively near-term path to a new medicine. Vasconcelles called ACC a “dire clinical situation” with no approved therapies and said Day One is focused on moving the program “as quickly as possible” for patients. He also said there is an “emerging unmet need” in triple-negative breast cancer (TNBC) as topoisomerase-based ADCs move into earlier lines, though he characterized the company’s approach as sequential rather than anchored on TNBC.
On Emi-Le safety, Vasconcelles said the company plans to provide a mid-year update and emphasized that clinical data to date show “no hematologic toxicity, no neuropathy, no ocular toxicity” with its auristatin-based payload and novel linker, which he said is notable given the broader context of earlier-generation linker-payload approaches.
In closing remarks, York said he believes Day One is building a “durable growth story” with OJEMDA and emphasized execution by the company’s employees, including work integrating the Mersana acquisition.
About Day One Biopharmaceuticals (NASDAQ:DAWN)
Day One Biopharmaceuticals, Inc (NASDAQ: DAWN) is a clinical-stage biopharmaceutical company focused on the discovery and development of targeted therapies for oncology. The company employs a precision medicine approach, leveraging biomarker-driven strategies to identify patient populations most likely to respond to its investigational compounds. By concentrating on well-validated molecular drivers of cancer, Day One seeks to deliver first-in-class or best-in-class therapies with the potential for meaningful clinical benefit.
The company’s pipeline includes several small-molecule candidates in various stages of development.
