Although this was a nonrandomized study, inclusion criteria remained consistent over trial execution, and participants on arms 1–4 versus arm 5 had similar baseline characteristics for age, sex, KPS, IDH mutation status, O6-methylguanine DNA methyltransferase (MGMT) methylation status, H score, multifocal disease, tumor resections and steroid administration at registration (Table 1 and Extended Data Table 3). Here, MGMT is linked to neoplasm.