Clinical Research Directory

Inclusion Criteria: * Age: 18 years or older * Histological confirmation of supra-tentorial GBM * KPS \> 60 * Neurological function 0 or 1 * Adequate bone marrow as defined below: Absolute neutrophil count (ANC) ≥ 1500 cells/mm3. Platelets ≥ 100,000 cells/mm3 Hemoglobin ≥ 10 g/dl. * Adequate renal function, as defined below: * Creatinine clearance of \>60 ml/min/1.73m2 (using the Cockcroft Gault equation for eGFR) within 14 days prior to study registration * Adequate hepatic function, as defined below: * Bilirubin of 1.7 to 18.9 umol/L within 14 days prior to study registration * ALT ≤ 3 x normal range within 14 days prior to study registration * Neo-adjuvant TMZ and Metformin to start within 4 weeks of surgery * Concomitant TMZ and Metformin and accelerated Hypofractionated EBRT to start at least 2 weeks after adjuvant TMZ starting date, and no later than five weeks from surgery. * Surgical diagnosis/intervention may include: partial or near total resection * Patients must have recovered from the effects of surgery, postoperative infection and other complications before study registration. * A diagnostic contrast-enhanced MRI or CT scan of the brain must be performed preoperatively and postoperatively. The postoperative scan must be done within 28 days prior to the initiation of neo-adjuvant TMZ. Preoperative and postoperative scans must be the same type. Patients unable to undergo MR imaging can be enrolled provided pre- and post-operative contrast-enhanced CT scans are obtained and are of sufficient quality. * History/physical examination, including neurologic exam within 14 days prior to study registration. * Documentation of steroid doses within 14 days prior to study registration and stable or decreasing steroid dose within 5 days prior to registration. * For females of child-bearing potential, negative serum pregnancy test within 72hours prior to starting TMZ and Metformin. Women of childbearing potential and male participants must practice adequate contraception. * Adequate tissue specimen for MGMT status analysis. * Able to sign an informed study-specific consent Exclusion Criteria: * Diabetic patients both type I and type II. * No tissue provided for MGMT promoter methylation status determination. * Margin of contrast-enhanced residual mass closer than 15 mm from the optic chiasm or optic nerves. * Prior invasive malignancy (except for non-melanoma skin cancer) unless disease free for ≥ 3 years * Recurrent or multifocal GBM. * Prior chemotherapy or radio-sensitizers for cancers of the head and neck region; prior chemotherapy for a different cancer is allowable. * Severe, active co-morbidity, defined as follows: * Acute or chronic renal failure. * Unstable angina and/or congestive heart failure requiring hospitalization * Transmural myocardial infarction within the last 6 months * Acute bacterial or fungal infection requiring intravenous antibiotics at the time of registration. * Chronic Obstructive Pulmonary Disease exacerbation or other respiratory illness requiring hospitalization or precluding study therapy at the time of registration * Acquired Immune Deficiency Syndrome (AIDS) based upon current CDC definition. * Major medical illnesses or psychiatric impairments that in the investigator's opinion will prevent administration or completion of protocol therapy. * Pregnancy or women of childbearing potential and men who are sexually active and not willing/able to use medically acceptable forms of contraception; this exclusion is necessary because the treatment involved in this study may be significantly teratogenic. * Pregnant or lactating women, due to possible adverse effects on the developing foetus or infant due to study drug. * Prior allergic reaction to Temozolomide or Metformin. * Patients treated on any other therapeutic clinical protocols within 30 days prior to study entry or during participation in the study