A phase II study of gemcitabine plus paclitaxel in patients with metastatic breast cancer and prior anthracycline treatment

Aim: To investigate the efficacy and safety of gemcitabine-paclitaxel in Chinese patients with metastatic breast cancer following anthracycline failure in a multicenter, open-label, single-arm, phase II clinical trial.Methods: Chinese female patients with unresectable, locally recurrent or metastatic breast cancer who had relapsed after neo-adjuvant anthracycline-based chemotherapy were included. All patients had measurable disease and an Eastern Cooperative Oncology Group performance status of 0 or 1 at baseline. Gemcitabine (1250mg/m²)-paclitaxel (175mg/m²) was administered on a 3-weekly schedule until disease progression, and patients were followed up for 12months (post-enrolment). The primary end point was objective response rate; secondary end points included duration of response, progression-free survival and overall survival.Results: Overall 60 patients were enrolled. Their mean age was 46.9 (SD±9.0) years and 90% of patients had metastatic disease. All patients had previously received chemotherapy. A total of 48 patients (80%) completed the 12-month follow up, and 40 patients (67%) completed at least six cycles of study therapy. The objective response rate (complete response+partial response) was 50% (95% CI: 36.6-63.4). Median duration of response was 5.6months (95% CI: 4.4-7.6) and median progression-free survival was 7.6months (95% CI: 5.8-8.8). Overall survival at 12months was 87% (95% CI: 77.9-95.2). Laboratory toxicities were primarily hematologic, including Grade 3 and 4 neutropenia (n=27 [45%]) and leukopenia (n=18 [30%]). Eight patient deaths (13%) were not treatment-related.Conclusion: Gemcitabine-paclitaxel combination therapy is an active and well-tolerated chemotherapy regimen, with expected and manageable toxicity in Chinese patients with metastatic breast cancer.