A Phase 2 and Pharmacodynamic Study of Sitagliptin in Patients With Progressive Grade 4 Gliomas
Trial Parameters
Brief Summary
The purpose of this study is to evaluate whether treating glioblastoma patients with sitagliptin can improve immune response against the tumor by targeting specific immune cells called myeloid-derived suppressor cells (MDSCs) that suppress your body's natural immune response against cancer. Sitagliptin is an investigational drug for this condition that works by inhibiting an enzyme called dipeptidyl peptidase 4 (DPP-4), which MDSCs rely on to enter the brain and function. While sitagliptin is FDA-approved for diabetes treatment, its use in glioblastoma is investigational (experimental).
Eligibility Criteria
Inclusion Criteria: 1. Participants must have histologically or cytologically confirmed WHO grade 4 glioma (including tumors with molecularly defined grade 4 astrocytoma) for whom a clinically-indicated tumor resection is planned. 2. Participants must not have received sitagliptin or other gliptins. 3. Participants must, in the opinion of the investigator be able to tolerate a pre-operative dexamethasone dose of 4 mg/d or the equivalent dose of an alternate glucocorticoid. 4. Age \>18 years 5. Karnofsky performance status ≥ 60% 6. Participants must have adequate organ function and laboratory parameters within 21 days of study entry as defined below: * Hemoglobin ≥ 9 g/dl * Absolute neutrophil count ≥ 1,500/mcL * Platelet count ≥ 100,000/mcL * Total bilirubin \< 1.5x institutional upper limit of normal (ULN) * AST (SGOT) ≤ 3x institutional ULN * ALT (SGPT) ≤ 3x institutional ULN * Calculated creatinine clearance \> 50 mL/min or creatinine \< 1.5x institutional upper limit of normal (ULN