Inclusion Criteria:

• Histological or cytological diagnosis of breast carcinoma with evidence of unresectable, locally recurrent, or metastatic disease. Lesions should not be amenable to surgery or radiation of curative intent.
• Presence of metastatic or local-regional recurrent disease, according to the American Joint Committee on Cancer
• Uni-dimensionally measurable lesions with clearly defined margin that are clearly measurable by following methods according to computerized tomography (CT), Chest x-ray or clinical examination, according to RECIST criteria
• Patients with unresectable, locally recurrent or metastatic breast cancer who, were pre-treated with anthracyclines with/without taxanes (paclitaxel, docetaxel)containing chemotherapy either in neoadjuvant/adjuvant or 1st line metastatic setting will be enrolled into the study. Prior chemotherapy has to be terminated 4 weeks prior. Study randomization and disease progression under this therapy has to be documented, also patients must have completely recovered from all acute chemotherapy related toxicities (with exception of alopecia).

Prior radiotherapy must be completed at least 30 days before study entry. Patients must have recovered from the acute toxic effects of the treatment prior to study enrollment (except for alopecia). Lesions that have been radiated cannot be included as sites of measurable disease unless clear tumor progression has been documented in these lesions since the end of radiation therapy.

Exclusion Criteria:

• Have received treatment within the last 30 days with an investigational drug for any indication before study entry.
• Concurrent administration of other tumor therapy, including cytotoxic chemotherapy, surgery of cancer, radiotherapy, hormonal therapy and immunotherapy (including Herceptin)
• Active infection that in the opinion of the investigator would compromise the patient's ability to tolerate therapy, unless adequately treated.
• Serious concomitant disorders that would compromise the safety of the patient or compromise the patient's ability to complete the study, at the discretion of the investigator.
• Second primary malignancy that is clinically detectable at the time of consideration for study enrollment(except in situ carcinoma of cervix or adequately treated basal cell carcinoma of skin)