Day One Biopharmaceuticals announced the recently completed submission of the rolling New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) for Tovorafenib as a monotherapy in relapsed or progressive pediatric low-grade glioma (pLGG). The Company anticipates the FDA will file the rolling NDA by mid-November 2023. FIREFLY-1 is an open-label, pivotal Phase 2 trial, which treated a total of 137 patients across two study arms. Arm 1 evaluated tovorafenib in 77 patients as a once-weekly monotherapy in patients aged 6 months to 25 years with relapsed or progressive pLGG.

The primary endpoint of the trial is ORR by Response Assessment for Neuro-Oncology High-Grade Glioma (RANO-HGG) criteria. Secondary endpoints include ORR by Response Assessment in Pediatric Neuro-Oncology Low-Grade Glioma (RAPNO-LGG), progression-free survival (PFS), duration of response (DOR), time to response, clinical benefit rate and safety. The NDA submission also includes an exploratory analysis of ORR by Response Assessment for Neuro-Oncology Low-Grade Glioma (RANO-LGG).

All data have been assessed by a blinded Independent Review Committee (IRC).