Second Line ERIbulin Followed by CApecitabine or the Reverse Sequence in HER2-negative Metastatic Breast Cancer Patients

Patients who are considered eligible for the study treatment, will be randomly allocated within the two study arms. ARM A: * Second line Eribulin 1.23 mg/m2 i.v. on day 1, 8 every 21 days * third line Capecitabine 1250 mg/m2 orally twice per day on days 1 to 14 every 21 days ARM B: * Second line Capecitabine 1250 mg/m2 orally twice per day on days 1 to 14 every 21 days * Third line Eribulin 1.23 mg/m2 i.v. on day 1, 8 every 21 days Study treatment will be continued until disease progression, death, unacceptable toxicity, Investigator's decision or patient refusal of further treatment.