Gemcitabine plus paclitaxel versus paclitaxel monotherapy in patients with metastatic breast cancer and prior anthracycline treatment

Abstract

Purpose: The objective of this phase III global study was to compare the efficacy of gemcitabine plus paclitaxel (GT) versus paclitaxel in patients with advanced breast cancer. It was designed as a pivotal study for the approval of G for a breast cancer treatment indication. Patients and Methods: Patients who relapsed after adjuvant anthracyclines were randomly assigned to gemcitabine,1,250 mg/m2 days 1 and 8 plus paclitaxel, 175 mg/m 2 on day 1; or, to paclitaxel at same dose on day 1 (both arms administered every 21 days, unblinded). The primary end point was overall survival (OS) and secondary end points were time to progression (TTP), response rate (RR), progression-free survival, response duration, and toxicity. This final OS analysis was planned at 380 deaths. Results: A total of 266 patients were randomly assigned to GT and 263 to paclitaxel. Median survival on GT was 18.6 months versus 15.8 months on paclitaxel (log-rank P = . 0489), with an adjusted Cox hazard ratio of 0.78 (95% CI, 0.64 to 0.96; P = .0187). The TTP was longer (6.14 v 3.98 months; log-rank P = .0002) and the RR was better (41.4% v 26.2%; P = .0002) on GT. There was more grade 3 to 4 neutropenia on GT and grade 2 to 4 fatigue and neuropathy were slightly more prevalent on GT. Conclusion: This phase III study documents a role for gemcitabine in advanced breast cancer after anthracycline-based adjuvant therapy. The results establish GT as a reasonable choice for women who require cytoreduction with manageable toxicities and validate ongoing testing of GT in the adjuvant setting. © 2008 by American Society of Clinical Oncology.