ERBB2 and breast cancer: In a U.S. multicenter, randomized, placebo-controlled, double-blind trial, Guglin et al46 included 468 patients with HER2-positive early breast cancer treated with trastuzumab from 127 participating sites who were stratified by prior anthracycline use and assigned in a 1:1:1 fashion to treatment with lisinopril, carvedilol, or placebo.