Experimental:Dabrafenib, Trametinib & Phenformin
This is a multi-institution single-arm phase I trial with an expansion cohort at the MTD of Phenformin, in patients with metastatic BRAFV600E/K mutated melanoma. In the dose escalation phase, cohorts of patients will be treated with standard dose Dabrafenib (150 mg PO BID) plus Trametinib (2 mg PO QD) and increasing doses of Phenformin. In the dose-escalation phase of the trial, both patients who have already been treated with a BRAF and/or MEK inhibitor, and treatment-naïve patients will be eligible. The maximally tolerated Phenformin dose was determined to be 100 mg BID. The dose-expansion cohort will enroll up to 10 patients who are treatment- naïve for BRAF inhibitor. In this cohort, patients may be treated with any of the 3 FDA-approved BRAFi/MEKi combinations: dabrafenib/trametinib, vemurafenib/cobimetinib, or encorafenib/binimetinib.