An experimental drug targeting a common mutation in melanoma successfully shrank tumors that spread to the brain in nine out of 10 patients in part of an international phase I clinical trial reported in the May 18 issue of The Lancet.

The drug dabrafenib, which targets the Val600 BRAF mutation that is active in half of melanoma cases, also cut the size of tumors in 25 of 36 patients with late-stage melanoma that had not spread...