Trastuzumab (TZB) is an established therapy for HER2-positive breast cancer. The use of TZB is commonly associated with cardiotoxicity manifesting as asymptomatic decrease in left ventricular ejection fraction (LVEF) or overt heart failure. Several studies demonstrated favorable effects of angiotensin-converting enzyme (ACE) inhibitors and β-blockers (BBs) in the prevention of chemotherapy-induced cardiotoxicity. We hypothesize that patients, randomized to receive an ACE inhibitor or a BB during trastuzumab therapy for breast cancer, will maintain a higher LVEF than patients randomized to placebo.

We designed a prospective, multicenter, randomized, phase II placebo-controlled clinical trial to evaluate the effects of an ACE inhibitor (lisinopril) and a BB (carvedilol phosphate–extended release) on cardiotoxicity in patients with breast cancer who are receiving adjuvant or neoadjuvant TZB therapy. The primary objectives include (1) comparison of incidence of cardiotoxicity and (2) comparison of LVEF as a continuous variable in between the arms. Cardiotoxicity was defined as an absolute decrease in LVEF from baseline of ≥10% at follow-up or an absolute decrease of ≥5% in LVEF from baseline for individuals with <50% LVEF at follow-up.

The target accrual is 468 participants, representing patients both with and without anthracycline exposure. The enrollment is completed. The trial is co-sponsored by University of South Florida and National Cancer Institute. The LVEF is being evaluated by echocardiography or multigated acquisition scan.

If we can demonstrate that the use of an ACE inhibitor or a BB can reduce the degree of TZB-induced cardiotoxicity, it is hoped that patients will receive complete and uninterrupted TZB therapy for breast cancer without compromising cardiac function.