Anti-PD-1 mAb Plus Metabolic Modulator in Solid Tumor Malignancies

The prognosis for patients with metastatic disease remains poor. The use of immunotherapy in the treatment of cancer is based on the premise that tumors evade the endogenous immune response by being recognized as self, and not non-self. The recent success of immune-modulating agents in patients with refractory solid tumors has provided proof-of-concept of the efficacy of immune system activation as a therapeutic modality. Tumors develop immune resistance using different mechanisms; the goal of immunotherapy is to counteract these resistance mechanisms, allowing the endogenous immune system to reject tumors. One of those mechanisms of resistance is tumor hypoxia This study aims to examine whether Metformin and Rosiglitazone will reduce tumor oxygen consumption, creating a less hypoxic T cell environment, with pharmacologic remodeling of the TME leading to restored anti-tumor T cell effector function and as a result will act synergistically with anti-PD-1 mAb resulting in a higher response rate than with anti-PD-1 mAb alone. The safety and tolerability of if adding metformin or rosiglitazone to anti-PD-1 mAb therapy will assessed. Eligible patients will undergo pre-treatment biopsy and then will be randomized to one of three arms: 1. Anti-PD-1 mAb + Metformin 500mg PO BID 2. Anti-PD-1 mAb alone or 3. Anti-PD-1 mAb plus Rosiglitazone 4mg po qdaily. Patients will undergo post treatment biopsy after 5 weeks (+/- 7 days) of treatment and then continue treatment for up to 2 years, or until progression of disease or unacceptable toxicity, whichever occurs first.