MGMT and glioblastoma: GBM AGILE (NCT03970447) is an international, seamless Phase II/III response adaptive randomization platform trial designed to evaluate multiple therapies in newly diagnosed and recurrent glioblastoma, in which, regorafenib is proposed as first-line treatment in patients with newly diagnosed MGMT unmethylated glioblastoma, after concomitant chemoradiotherapy treatment with temozolomide, or as treatment at the time of the first relapse in recurrent glioblastoma patients, regardless of the MGMT methylation status.