Combination therapy with BRAF and MEK inhibitors for melanoma: latest evidence and place in therapy

Treatment with BRAF inhibitors such as vemurafenib or dabrafenib in patients with advanced BRAFV600 mutated melanoma has shown objective tumor responses in approximately half of the patients. However, the duration of responses is limited in a majority of these patients, with progression-free survival rates around 6 months due to tumor progression from development of acquired resistance. Preclinical studies have suggested that concurrent inhibition of the BRAF kinases and MEK of the mitogen-activated protein kinase (MAPK) pathway could decrease MAPK-driven acquired resistance, resulting in longer duration of responses, higher rate of tumor responses, and a decrease in the cutaneous toxicities observed from paradoxical MAPK pathway activation with BRAF inhibitor monotherapy. This review provides an overview of the currently available clinical trial data on BRAF and MEK inhibitors together and in combinations with other therapeutic agents.