Table 1 Main inclusion and exclusion criteria for entry in the study

Adult women with HER-2 negative MBC

Previous chemotherapy for metastatic disease

MBC relapsed after receiving one adjuvant/neoadjuvant chemotherapy containing an anthracycline, unless clinically contraindicated

Previous chemotherapy with gemcitabine in any setting of disease

Could have received a prior neoadjuvant or adjuvant taxanes regimen as long as it was ≥12 months since completion of the treatment

Patients with second primary malignancy (except in situ carcinoma of the cervix or adequately treated non-melanoma carcinoma of the skin or other malignancy treated at least 5 years previously with no evidence of recurrence)

Measurable disease as defined by RECIST 1.0 (however patients with only bone metastases were included in the study),

Pre-existing sensorial or motor neuropathy NCI-CTC grade >1

Previous hormonal therapy for adjuvant setting or metastatic disease (≤2 lines), or immunotherapy, was allowed and should have been completed before the enrolment

Inflammatory breast cancer without evidence of metastatic disease

Performance status ≥70 on the Karnofsky Scale

Patients with serious concomitant systemic disorders (e.g., uncontrolled active cardiovascular diseases and/or myocardial infarction within the preceding 6 months)

Life expectancy ≥12 weeks

Patients with clinical evidence of symptomatic brain metastasis

Adequate bone marrow and liver/renal function

Pregnancy or breast-feeding

Prior radiotherapy should have been completed 4 weeks before study entry

Patients with reproductive potential not using an approved contraceptive method if appropriate (except hormonal substitutive therapy)