The pediatric RP2D of ulixertinib was established as 260 mg/m2/dose PO BID....Three patients with CNS tumors achieved stable disease > 6 months (HGG with BRAF fusion, 15 cycles; glioneuronal tumor with BRAF V600E, 9 cycles; low-grade glioma with BRAF fusion, 7 cycles)…. Clinical benefit of prolonged disease control was observed in 3 patients with BRAF-altered gliomas and glioneuronal tumors.