Phase II study of eribulin with trasutuzumab for pretreated locally advanced or metastatic HER2-positive breast cancer.

e12505Background: Eribulin mesylate demonstrated a survival benefit in patients with locally recurrent or metastatic breast cancer who previously received 2 or more chemotherapy regimens. There are limited studies reported about the efficacy of eribulin with trastuzumab as first-line therapy for locally advanced or metastatic HER2-positive breast cancer. The aim of this study was to assess the efficacy and safety of eribulin with trastuzumab as late-line therapy for locally advanced or metastatic HER2-positive breast cancer. Methods: In this multicenter, phase II, single-arm study, patients with locally advanced or metastatic HER2 positive breast cancer who previously received at least one chemotherapeutic regimen, received eribulin at 1.4 mg/m2 intravenously (I.V.) on days 1 and 8 of each 21-day cycle with an initial trastuzumab dose of 8 mg/kg I.V. on day 1, followed by 6 mg/kg of trastuzumab on day 1 of each subsequent cycle. The primary end point was ORR, and secondary end points included PFS and safe...