A Phase Ii, Multicenter, Single-Arm Study Of Eribulin Mesilate As First-Line Therapy For Her2-Negative Locally Advanced Or Metastatic Breast Cancer.

e12017 Background: Eribulin mesilate, one of the tubuline inhibitors, is usually used for metastatic breast cancer (MBC) as a third or later-line chemotherapy. Eribulin showed survival benefit equivalent to capecitabine with good quality of life in upfront line chemotherapy. We conducted this single arm phase II trial to evaluate efficacy of eribulin as first-line treatment. Methods: The patients with HER2-negative unresectable locally advanced or MBC with measurable lesion who never received chemotherapy. They received 1.4 mg/m2 of eribulin intravenously on day1 and 8 of each three-week cycles until disease progression or intolerable toxicity occured. The primary endpoint was overall response rate (ORR). The secondary endpoints were progression free survival (PFS), time to treatment failure (TTF), overall survival, and safety. Mandatory efficacy evaluation was performed every six weeks. A total of 32 assessable patients were required to test the null hypothesis that the true confirmed response rate is at...