CTLA4 and metastatic melanoma: In an effort to address and combat resistance to monotherapy, current treatments for metastatic melanoma either combine the BRAF kinase inhibitor dabrafenib with the MEK inhibitor trametinib or recommend the monoclonal antibody, ipilimumab, against the immune checkpoint inhibitor cytotoxic T-lymphocyte antigen 4, CTLA-4, for first-line therapy [17, 35, 36].