In the BRAF Inhibitor in Melanoma-3 (BRIM-3) trial, a phase 3 randomised open-label study comparing vemurafenib with dacarbazine in BRAF V600E- and BRAF V600K-mutant melanoma, 38 % of patients receiving vemurafenib required dose modifications because of toxicity [3]. This evidence concerns the gene BRAF and melanoma.