Trametinib had good results for metastatic melanoma carrying the BRAF V600E mutation in a phase III clinical trial. In this mutation, the amino acid valine (V) at position 600 within the BRAF gene has become replaced by glutamic acid (E) making the mutant BRAF gene constituitively active.
In May 2013, trametinib was approved as a single-agent by the Food and Drug Administration for the treatment of patients with V600E mutated metastatic melanoma. Clinical trial data demonstrated that progression on single-agent trametinib occurs within 6 to 7 months. To overcome this, trametinib was combined with the BRAF inhibitor dabrafenib. As a result of this research, on January 8, 2014, the FDA approved the combination of dabrafenib and trametinib for the treatment of patients with BRAF V600E/K-mutant metastatic melanoma.