Capecitabine Effective in Taxane-Refractory Breast Cancer

ASCO—A multicenter, open-label, phase II study has confirmed results of the pivotal study of capecitabine (Xeloda) for treatment of taxane-refractory metastatic breast cancer. In this study, 25% of patients with measurable disease treated with capecitabine responded, with a median duration of response of 8.3 months, median time to progression of 3.2 months, and median survival of 12.3 months.

“This study is encouraging in that it supports previous findings that even patients with tough-to-treat tumors who have failed first-line chemotherapy may experience a positive response with Xe-loda,” Joanne Blum, MD, PhD, of the Physician Reliance Network (PRN) Research, Inc., said at an ASCO poster session. The study was conducted under the auspices of PRN Research and Baylor University Medical Center-Charles A. Sammons Cancer Center, Dallas.

Five centers in the US and France enrolled 75 patients with bidimensionally measurable disease (69 patients) or evaluable disease (5 patients). All patients had failed at least two previous chemotherapy regimens for advanced/metastatic disease, one of which included paclitaxel (Taxol) or docetaxel (Taxotere).

Patients received twice-daily oral capecitabine at 2,510 mg/m²/day for 14 days, followed by a 1-week rest period and repeated in 3-week cycles.

Of the 69 patients with measurable disease, 17 (25%) responded, all with a partial response; 30% had stable disease. “Similar response rates were seen in both subpopulations of paclitaxel- and docetaxol-refractory patients,” she said.

The objective response rate in paclitaxel failing or resistant tumors was 27%, thereby confirming the results of the pivotal study that led to FDA approval of the agent. In that study, 20% of paclitaxel-refractory patients responded. The 20% response rate in docetaxel-refractory patients showed that the agent also has activity in these patients.

Of 40 patients with symptoms at baseline, 8 (20%) had a clinical benefit. Of 27 patients with baseline pain of more than 20 mm on a visual analog scale, 7 (26%) had a significant improvement in pain.

Adverse effects associated with capecitabine were “predictable and manageable,” Dr. Blum said. Hand-foot syndrome, diarrhea, stomatitis, and nausea were the only grade 3-4 treatment-related adverse events that occurred in more than 10% of patients. Only 4.1% of patients had a grade 4 treatment-related event, he said, and there were no treatment-related deaths.