See tables. RT Phase Dose level Temozolomide dose Dose reduce to 0 (starting dose) 75 mg/m 2 60 mg/m 2 -1b 60 mg/m 2 50 mg/m 2 -2b 50 mg/m 2 40 mg/m 2 53 Abbreviated Title: GBM Pembro HSPPC Version Date: 03/26/2024 Post RT phase Dose level Temozolomide dose Dose reduce to 0 (starting dose for cycle 2 and beyond)200 mg/m2150 mg/m2 -1 (starting dose for cycle 1)150 mg/m2125 mg/m2 -2 125 mg/m2100 mg/m2 3.10.5 HSPPC-96/Placebo Dose Modifications For grade 1 or 2 reactions considered related to HSPPC-96/Placebo, manage symptoms according to institutional procedures. Continue on study.