ERBB2 and gastric cancer: This approval was granted after the pivotal phase III ToGA trial showed that, among 584 patients with previously untreated HER2-overexpressing advanced gastric cancer, the addition of trastuzumab to standard chemotherapy prolonged median overall survival (OS) from 11.1 to 13.8 months, as compared to patients treated with chemotherapy alone (p = 0.0046) [2].