ERBB2 and breast carcinoma: A Phase II study (NCT02091141) evaluated the efficacy of trastuzumab plus pertuzumab (Perjeta®®), an anti-HER2 monoclonal Ab with complementary binding kinetics used in HER2+ breast cancer, in previously treated mUC with an ORR of 33% in those with HER2 overexpression [27].