A drug used to treat advanced melanoma that has a mutated (changed) form of a cell protein called BRAF. It is also being studied in the treatment of other types of cancer. BRAF (V600E) kinase inhibitor RO5185426 blocks this mutated protein, which may stop the growth of cancer cells. It is a type of kinase inhibitor and a type of targeted therapy agent. Also called PLX4032, RG7204, vemurafenib, and Zelboraf.