A drug that targets the RAS signalling cascade — which is thought to drive tumour growth in 20% of cancers — improves survival in some patients with advanced melanoma.

The drug, called trametinib, inhibits MEK, a protein that amplifies cancer-promoting signals. Keith Flaherty at the Massachusetts General Hospital in Boston and his team tested trametinib in melanoma patients with a mutated version of a RAS-pathway protein BRAF, which is mutated in 50% of advanced melanoma patients. A total of 322 patients were randomly assigned to receive either trametinib or standard chemotherapy.

Twenty-two percent of patients responded to trametinib, which delayed disease progression by 3 months longer than chemotherapy alone.

N. Engl. J. Med. http://dx.doi.org/10.1056/nejmoa1203421 (2012)