BERLIN (EGMN) - An investigational agent that targets the BRAF mutation and is present in at least half of melanoma patients has shown impressive results in a second phase I trial.Response rates with the oral agent PLX4032 reached an unprecedented 70% in metastatic melanoma, signaling a fundamental shift in the way this deadly disease will be treated."What's very encouraging is actually that the response rate in nonmutated melanoma is 0%; so we know exactly what we're doing," European Cancer Organization...