Swiss drugmaker Novartis notched a trial win for its drug cocktail against skin cancer on Monday, while a rival treatment from Roche with slipping sales failed in a separate study with a similar patient group.

All the medicines were tested in melanoma patients who had undergone surgery to cut out tumors and had a genetic mutation called BRAF, making them likely to respond to the targeted cancer pills. Patients with BRAF mutations constitute around half of the melanoma population.

Novartis's mix of Tafinlar and Mekinist slashed the risk of melanoma returning or death by 53 percent versus placebo in patients with stage III disease, according to data released at the European Society for Medical Oncology congress in Madrid.