Epirubicin With Cyclophosphamide Followed by Docetaxel With Trastuzumab and Bevacizumab as Neoadjuvant Therapy for HER2-Positive Locally Advanced Breast Cancer or as Adjuvant Therapy for HER2-Positive Pathologic Stage III Breast Cancer: A Phase II Trial of the NSABP Foundation Research Group, FB-5.

BACKGROUND: The purpose of this study was to determine the cardiac safety and clinical activity of trastuzumab and bevacizumab with docetaxel after epirubicin with cyclophosphamide (EC) in patients with HER2-positive locally advanced breast cancer (LABC) or pathologic stage 3 breast cancer (PS3BC).

PATIENTS AND METHODS: Patients received every 3 week treatment with 4 cycles of EC (90/600 mg/m2 ) followed by 4 cycles of docetaxel (100 mg/m2 ). Targeted therapy with standard-dose trastuzumab with bevacizumab 15 mg/kg was given for a total of 1 year. Coprimary end points were (1) rate of cardiac events (CEs) in all patients defined as clinical congestive heart failure with a significant decrease in left ventricular ejection fraction or cardiac deaths; and (2) pathologic complete response (pCR) in breast and nodes in the neoadjuvant cohort. An independent cardiac review panel determined whether criteria for a CE were met.

RESULTS: A total of 105 patients were accrued, 76 with LABC treated with neoadjuvant therapy and 29 with PS3BC treated with adjuvant therapy. Median follow-up was 59.2 months. Among 99 evaluable patients for cardiac safety, 4 (4%; 95% confidence interval [CI], 1.1%-10.0%) met CE criteria. The pCR percentage in LABC patients was 46% (95% CI, 34%-59%). Five-year recurrence-free survival (RFS) and overall survival (OS) for all patients was 79.9% and 90.8%, respectively.

CONCLUSION: The regimen met predefined criteria for activity of interest with an acceptable rate of CEs. Although the pCR percentage was comparable with chemotherapy regimens with trastuzumab alone the high RFS and OS are of interest in these high-risk populations.