Patients with histologically confirmed metastatic breast cancer overexpressing HER2 were eligible if pretreated with anthracycline in either the adjuvant or palliative setting. Treatment consisted of weekly trastuzumab (2 mg/kg/week for up to one year after a loading dose of 4 mg/kg in week 1) and paclitaxel (90 mg/m², administered in weeks 1–6 and 8–13).

Twenty-seven German centers enrolled 121 patients. The median number of metastatic sites was two (range 1–5); 38% of patients had received chemotherapy for advanced disease. After a median 42 weeks of trastuzumab treatment, limited by disease progression in roughly half the patients, a best objective response rate (complete response+partial response) of 76% was achieved, including complete remissions in 29%. 74% of patients lived without tumor progression at six months. Median progression-free and overall survival were 9.4 (95% confidence interval [CI]: 8.1–11.3) and 22 months (95% CI: 17–46). After alopecia, Common Toxicity Criteria grade ≥2 toxicity was predominantly hematological (leukopenia [31%] and anemia [41%]); however, thrombocytopenia occurred in only 5%. Neurotoxicity was remarkably low. Two cardiac events (grades 2 and 3) were presumed treatment-related.