A phase II, multicenter, single-arm trial of eribulin as first or second line chemotherapy for HER2-negative advanced or metastatic breast cancer: Evaluation of efficacy, safety, and patient-reported outcomes.

Purpose Although eribulin is a suitable option for early-line treatment of metastatic breast cancer (MBC), data on first- or second-line use of eribulin for human epidermal growth factor receptor 2 (HER2)-negative MBC are still limited. Therefore, we conducted a phase II trial to investigate the efficacy and safety of eribulin for first- or second-line chemotherapy for HER2-negative MBC.