(UPCI 15-131) Dose-seeking and Efficacy Study of Pembrolizumab plus Vemurafenib for Therapy of Advanced Melanoma
The study plans to treat patients with pembrolizumab and thus blocking the PD-1/PD-L1 axis would render tumor-infiltrating lymphocytes (TILs) in the tumor parenchyma more functional as a consequence of BRAF inhibition, such that T cell activation by BRAFi would not be dampened by the PD-1/PD-L1 interaction. This combination would reverse dysfunction among T cells in the tumor parenchyma, maximizing T cell mediated immune anti-tumor efficacy. Progression free survival (PFS) with pembrolizumab in KEYNOTE-001 was 57% at 6 months, and 46.4% in the more recently reported phase III trial. PFS with vemurafenib treatment in BRIM-3 was ~50% at 6 months. Combined treatment with pembrolizumab and vemurafenib for BRAF mutant melanoma is hypothesized to be safe and to improve the PFS compared to these recent historical controls. Because this combination has not yet been tested, and because the primary objective is to assess safety, the investigators are staging accrual in the first phase of the trial. The study aims to accrue up to 50 patients to the mTPI design of this study with the expectation that there will be at least 30 patients treated at RP2D. In case there are less than 30 patients on the RP2D, additional patients will be accrued. Patients will continue to receive treatment with pembrolizumab and vemurafenib until disease progression or toxicity. Patients with treatment response and no dose limiting toxicity may receive treatment with pembrolizumab for up to 24 months.