Per independent assessment in 69 RANO-evaluable patients, ORR was 64%, [3 CR, 41 PR (10 unconfirmed) and 19 SD] with a clinical benefit rate of 91%. Responses were achieved in tumors with BRAF fusions and V600E mutations, including those previously treated with MAPK inhibitors....Tovorafenib was generally well tolerated and showed encouraging evidence of antitumor activity in children and young adults with recurrent/progressive BRAF-altered pLGG.

Day One Biopharmaceuticals...today announced positive initial data from the first 22 Response Assessment for Neuro-Oncology (“RANO”)-evaluable patients enrolled in the ongoing, open-label, single-arm, pivotal Phase 2 FIREFLY-1 clinical trial….FIREFLY-1 is evaluating tovorafenib (DAY101) as once-weekly monotherapy in patients aged 6 months to 25 years with relapsed or progressive pLGG....Initial data from the first 25 patients enrolled in the trial demonstrate...64% ORR and 91% CBR (partial response/unconfirmed partial response + stable disease) in the 22 RANO-evaluable patients...14 partial responses (13 confirmed responses and 1 unconfirmed response)...6 patients with stable disease....Responses were observed in patients with both BRAF fusions and BRAF V600E mutations who received prior MAPK-targeted therapy...