Capecitabine + Bendamustine in Women With Pretreated Locally Advanced or Metastatic Her2-negative Breast Cancer

Inclusion Criteria: * Signed informed consent * Female patients, age ≥ 18 years (women of childbearing potential must have a negative pregnancy test at screening and must use effective contraception) * Advanced or metastatic Her2-negative breast cancer, histologically confirmed * At least one measurable lesion according to RECIST criteria (Version 1.1) * Documented disease progression * Patients with progression after anthracycline and/or taxane treatment(palliative or adjuvant) * Life expectancy of at least 12 weeks * Performance status 0-2 * Hematologic: * ANC (absolute neutrophil count) ≥ 1.5 x 109/L * Hemoglobin ≥ 9 g/dL * Platelets ≥ 100 x 109/L * Liver Function: * Albumin ≥ 2.5 g/dL * Serum bilirubin ≤ 2 mg/dL * AST (Aspartate aminotransferase) and ALT (Alanine aminotransferase) ≤ 3 x ULN (Upper limit of Normal) without liver metastases * 5 x ULN if documented liver metastases * Renal Function: * Serum Creatinine ≤ 1.5 mg/dL OR Calculated Creatinine Clearance ≥ 40 mL/min Exclusion Criteria: * Pregnant or lactating women * Serious medical or psychiatric disorders that would interfere with the patient's safety or informed consent * Radiation of the target lesion within the last 4 weeks * Active bacterial, viral or fungal infection * Patients with clinically apparent brain metastases * Known Positivity for HIV * Positivity for Hepatitis B or C * History of other malignancy; patients who have been disease-free for 5 years or patients with a history of completely resected non-melanoma skin cancer or successfully treated in situ carcinoma are eligible. * Concurrent cancer therapy (chemotherapy, immunotherapy, antihormonal or biologic therapy) or concurrent treatment with an investigational drug * Antihormonal therapy must have been discontinued prior to start of treatment (if possible at least 3 weeks before) * Known hypersensitivity to the study drugs capecitabine and bendamustine or their excipients * Pretreatment with capecitabine (pretreatment with infusional 5-FU (Fluorouracil) in the adjuvant or neoadjuvant setting is allowed) or bendamustine * Treatment with sorivudine or derivates e.g. brivudin (Mevir©) within the last 4 weeks before and during study treatment with capecitabine