Numerous MDM2 inhibitors are in clinical development for a variety of cancers including GBM (e.g., idasanutlin, navtemadlin, APG-115, BI-907828, CGM097, siremadlin, and milademetan), and current clinical experience suggests these drugs can effectively modulate p53 accumulation and transcriptional activity in human tumors with tolerable normal tissue toxicities [47,53,54]. This evidence concerns the gene MDM2 and glioblastoma.