Cardiac Safety of Dual Anti-HER2 Therapy in the Neoadjuvant Setting for Treatment of HER2-Positive Breast Cancer

Abstract

Abstract Background Trastuzumab and pertuzumab are approved for the neoadjuvant treatment of human epidermal growth receptor 2 (HER2)-positive breast cancer, but cardiac safety data is limited. We report the cardiac safety of dose-dense doxorubicin and cyclophosphamide (AC) followed by paclitaxel, trastuzumab, and pertuzumab (THP) in the neoadjuvant setting followed by adjuvant trastuzumab-based therapy. Methods Fifty-seven patients treated with neoadjuvant dose-dense AC-THP followed by adjuvant trastuzumab-based therapy between September 1, 2013, and March 1, 2015, were identified. The primary outcome was cardiac event rate, defined by heart failure (New York Heart Association [NYHA] class III/IV) or cardiac death. Patients underwent left ventricular ejection fraction (LVEF) monitoring at baseline, after AC, and serially during 1 year of anti-HER2 therapy. Results The median age was 46 years (range 26–68). Two (3.5%) patients developed NYHA class III/IV heart failure 5 and 9 months after initiation of trastuzumab-based therapy, leading to permanent discontinuation of anti-HER2 treatment. Seven (12.3%) patients developed a significant LVEF decline (without NYHA class III/IV symptoms). The median LVEF was 65% (range 55%–75%) at baseline and 64% (range 53%–72%) after AC, and decreased to 60% (range 35%–70%), 60% (range 23%–73%), 61% (range 25%–73%), and 58% (range 28%–66%) after 3, 6, 9, and 12 months (± 6 weeks) of trastuzumab-based therapy. Conclusion The incidence of NYHA class III/IV heart failure after neoadjuvant AC-THP (followed by adjuvant trastuzumab-based therapy) is comparable to rates reported in trials of sequential doxorubicin and trastuzumab. Our findings do not suggest an increased risk of cardiotoxicity from trastuzumab plus pertuzumab following a doxorubicin-based regimen.