Phase 2, Open-label, Single-arm Study on the Use of Metformin as Adjunctive Therapy in High-grade Glioma

"The investigator will identify potential participants and confirm the diagnosis of GBM. Subjects will be screened within 6 weeks before starting treatment.~Treatment will involve:~* Administration of the standard or partial Stupp protocol (Radiotherapy + Temozolomide) in combination with Metformin for 6 weeks,~* Treatment with only Metformin for 4 weeks;~* Resumption of adjuvant TMZ + Metformin treatment continuously until the end of the enrollment period."