NEW YORK – Day One Biopharmaceuticals on Monday said it has dosed the first patient in a Phase Ib/II trial of its lead candidate, DAY101, as a monotherapy in patients with recurrent or progressive solid tumors with activating RAF alterations.
The umbrella trial, called FIRELIGHT-1, will evaluate DAY101 as a monotherapy in adults and adolescents 12 and older with RAF-altered solid tumors. The study has two parts: the Phase Ib portion that is evaluating DAY101 with its MEK inhibitor, pimasertib, and the Phase II DAY101 monotherapy portion.
The Phase II monotherapy part will include two cohorts, a melanoma cohort and a tissue agnostic cohort. The primary endpoint is overall response rate, and additional endpoints include safety, duration of response, progression-free survival, and time to response. Researchers will also evaluate changes in phosphorylated ERK and other relevant biomarkers.
Day One expects to begin the Phase Ib combination portion of the FIRELIGHT-1 trial in early 2022.
The company, based in South San Francisco, California, is also studying DAY101 in pediatric patients with recurrent or progressive low-grade gliomas harboring known BRAF alterations. Day One expects initial data from that study in the first half of 2022.
Earlier this year, Day One went public with an initial public offering of $160 million in shares of its common stock. Most of the funds from the IPO were expected to be used to advance DAY101.