Purity >98%. B-Raf is a MAP kinase kinase kinase, which functions downstream of Ras family GTPases to activate MEK1/2 and ERK1/2 signaling. A mutation of B-Raf in exon 15 at codon 600 where a valine is substituted by glutamic acid (V600E) has been linked to melanoma. Encorafenib is a selective inhibitor of B-RafV600E mutant melanoma cell proliferation (EC50 = 4 nM) with little activity against wild-type B-Raf or a panel of 100 other kinases (IC50 s = 900 nM). At oral doses of 6 mg/kg in human melanoma xenograft models, encorafenib was shown to decrease phosphorylation of the B-Raf substrate MEK.