Study of Olutasidenib and Temozolomide in HGG

This is a multicenter, international, phase II study of post-radiotherapy (RT) administration of olutasidenib to treat pediatric and young adult patients newly diagnosed with an IDH1-mutant HGG. The trial will include a feasibility cohort to identify the dose of olutasidenib that is feasible when given in combination with temozolomide as maintenance therapy after completion of focal radiotherapy in this patient population. Efficacy will be defined by progression-free survival (PFS) distribution of these patients after completion of radiotherapy treated with maintenance olutasidenib and TMZ for 13 cycles followed by 13 cycles of single agent olutasidenib compared to molecularly-stratified and matched historical controls. Objective radiographic response rates, agent-specific toxicities as well as the pharmacokinetic and pharmacodynamic properties of olutasidenib will also be assessed.