This study will include up to 40 participants with Grade 2 or Grade 3 IDH1-mutant glioma who have undergone surgery and received vorasidenib as their only treatment, experienced radiographic disease progression on vorasidenib (confirmed by Blinded Independent Central Review \[BICR\] per modified Response Assessment in Neuro-Oncology \[RANO\] 2.0), and are not in need of immediate chemotherapy or radiotherapy.
Histologically confirmed Grade 2 or 3 IDH-mutant astrocytoma or IDH-mutant and 1p19q co-deleted oligodendroglioma, according to WHO CNS 2021 criteria
IDH1 mutation (e.g., R132H/C/G/S/L) based on immunohistochemistry (IHC) (R132H only), PCR, or next generation sequencing (NGS).
Have had at least 1 prior surgery for glioma (biopsy, sub-total resection, or gross total resection).
Measurable disease per modified RANO 2.0 confirmed by BICR during Screening.
Any prior anticancer therapy other than surgery (biopsy, sub-total, or gross total resection) and vorasidenib for treatment of glioma.
Discontinued vorasidenib for toxicity or any reason other than radiographic disease progression
Prior treatment with anti-angiogenic agents such as Avastin (bevacizumab) or investigational agents for glioma.
Brainstem or spinal cord involvement either as primary location, site of multifocal involvement, or by significant tumor extension.