Data at ASCO from GlaxoSmithKline plc (LSE:GSK; NYSE:GSK) strengthen its next-in-line position in melanoma and show combining BRAF and MEK inhibitors may prolong PFS and reduce secondary malignancies compared to monotherapy using BRAF inhibitor Zelboraf vemurafenib from Roche (SIX:ROG; OTCQX:RHHBY).

GSK's BRAF inhibitor dabrafenib and its MAP kinase kinase 1 (MAP2K1; MEK1)/MEK2 inhibitor trametinib each met the primary endpoint of PFS improvement in separate Phase III trials. But the most tantalizing data came from an uncontrolled Phase I/II trial combining the two oral compounds. If the 10.8-month PFS result holds up in