CTNI-64. TRIAL IN PROGRESS: DIET2TREAT -- A RANDOMIZED MULTICENTER PHASE 2 TRIAL OF A KETOGENIC DIET VS STANDARD DIETARY GUIDANCE IN COMBINATION WITH STANDARD-OF-CARE TREATMENT FOR PATIENTS WITH NEWLY DIAGNOSED GLIOBLASTOMA

Abstract BACKGROUND Many glioblastoma (GBM) patients inquire about the potential therapeutic benefits of a high fat / low carbohydrate ketogenic diet (KD). Preclinical models and early-phase trials have shown encouraging results, but definitive evidence of clinical efficacy is lacking. METHODS We are conducting a multicenter randomized controlled phase 2 clinical trial (NCT05708352) of KD vs standard dietary guidance (SD) for patients with newly diagnosed GBM. All patients receive standard-of-care chemoradiation. Inclusion criteria: newly diagnosed GBM, age ≥ 18 years, Karnofsky Performance Status ≥ 70. Exclusion criteria: inability to wean steroids below 8 mg dexamethasone/day, Body Mass Index < 21 kg/m2, food preferences incompatible with KD. Patients are randomized 1:1 to implement either KD or SD for a study period of 18 weeks, starting alongside chemoradiation. The primary outcome is overall survival for patients randomized to the KD arm compared to those randomized to the SD arm. Secondary outcomes include progression-free survival, health-related quality-of-life (FACT-BR, FACIT-F), cognitive performance (HVLT-R, Trail-Making Test A/B), and physical activity (modified Godin leisure questionnaire, continuous activity monitoring (Fitbit)). Patients randomized to the KD arm will be provided a fingerstick monitor to check blood ketone and glucose levels twice daily. Glucose and ketone levels are also periodically monitored for patients on the SD arm. Blood, tumor, and stool samples are being collected for high throughput profiling to assess the effects of KD on metabolic markers and immune response. Target accrual is 170 patients over 5 years. Enrollment began in July 2023 and is ongoing. As of May 2024, the trial is open for enrollment at Cedars-Sinai and UCSF, and will be opening soon at Duke, St. John’s Cancer Institute, and the Medical College of Wisconsin. 13 patients have been randomized to date. Funding provided by NIH R01CA276919 and the Foundation for Metabolic Cancer Therapies.