An Exploratory Phase II Study of Eribulin Re-challenge After Short Term Therapy of 5-Fluorouracil for HER2 Negative, Advanced or Recurrent Breast Cancer

Background/Aim: In our previous study, first-line eribulin (ERI) showed 25 weeks of progression-free survival (PFS). This study investigated the efficacy and safety of ERI re-administration in metastatic breast cancer (MBC) patients. Patients and Methods: HER2-negative MBC patients who had never received chemotherapy for MBC received first-line ERI for 18 weeks if they did not have disease progression, and then one cycle of S-1 before ERI re-administration. Results: Twelve patients received ERI re-administration. The PFS of re-administered ERI was 13 weeks. Total duration of ERI use was 30 weeks. The incidence and severity of adverse events were consistent with previous reports. Conclusion: In the first-line setting, the total PFS of eribulin was extended by S-1 administration before disease progression, compared with that of our previous report.