ASCO: Day One Biopharma announces new FIREFLY-1 data for tovorafenib

Day One Biopharmaceuticals (Nasdaq: DAWN) shares leapt 33.8% to $18.19 in pre-market trading on Monday, after the company announced overall response rate of 67% and clinical benefit rate of 93% in 69 heavily pre-treated RANO-HGG evaluable patients in pediatric low-grade glioma trial.

Day One Bio shared the new data from its Phase II registrational FIREFLY-1 trial evaluating tovorafenib (DAY101) for relapsed or progressive pediatric low-grade glioma (pLGG) at the American Society of Clinical Oncology (ASCO).

“We believe the data presented at ASCO for monotherapy tovorafenib demonstrate durable responses in children with relapsed pLGG who have limited treatment options,” said Jeremy Bender, chief executive officer of Day One. "Based on the strength of the safety and efficacy data we’ve observed to date, we believe tovorafenib has a compelling clinical profile. We’re looking forward to continuing our collaboration with the FDA as we submit the remainder of the data over the next several months.”