CTNI-66. IDH-MUTANT GLIOMA PATIENTS TREATED WITH VORASIDENIB: ONGOING DATA FROM THE VORASIDENIB EXPANDED ACCESS PROGRAM

Abstract BACKGROUND Vorasidenib (VOR) is an oral, brain-penetrant dual inhibitor of mutant isocitrate dehydrogenase 1/2 (mIDH1/2) demonstrating clinical efficacy and safety in patients with mIDH1/2 glioma in the phase 3 INDIGO study (NCT04164901). Servier launched an expanded access program (EAP, NCT05592743) in November 2022 designed to provide access to VOR for patients with mIDH1/2 glioma. Early clinical outcomes of patients treated in this EAP are presented. METHODS Eligible participants were aged ≥12 years with mIDH1/2 glioma and, in the opinion of the treating oncologist, would potentially benefit from treatment with VOR. Safety assessments occur every two weeks for the first two 28-day cycles, then monthly for the duration of treatment. RESULTS As of the March 31, 2024 data cutoff, 71 participants have initiated treatment with VOR. Mean (SD) age was 42.7 (14.8) years; 39 (55%) were male; and 34 (48%) with astrocytoma. mIDH mutation status was 46 (65%) mIDH1. One participant had separate tumors with either mIDH1 or mIDH2 identified. The majority of participants had grade 2 gliomas (n=51 [72%]) and non-contrast–enhancing disease (n=49 [69%]). As of the data cutoff, 62 (87%) participants remain on treatment, with the majority initiating treatment within the past 6 months (n=49 [69%]). Nine (13%) participants have discontinued treatment due to: radiographic progressive disease (n=3); clinical progressive disease (n=4); adverse event (AE) unrelated to treatment (n=1); or other reason (n=1). Three participants have died (disease progression [n=2], unrelated infection [n=1]). At least one AE of any grade was seen in 35 (49%) participants, with 4 (6%) experiencing unrelated serious AEs. Eight (11%) patients had AEs of special interest (defined as grade 2 or higher ALT/AST elevations). Ten (14%) patients had AEs that led to dose interruption and one (1%) patient had dose reduction. Additional treatment duration and various subgroup analyses will be presented.