Survival Benefit with Capecitabine/Docetaxel Versus Docetaxel Alone: Analysis of Therapy in a Randomized Phase III Trial

Abstract

In a large phase III trial of 511 patients with anthracycline-pretreated advanced/metastatic breast cancer, capecitabine/docetaxel combination therapy was shown to have significantly superior efficacy compared with single-agent docetaxel, including superior progression-free and overall survival and objective response rate. An updated survival analysis with ≥ 27 months follow-up shows that patients receiving combination therapy maintained significantly superior survival (hazard ratio [HR], 0.777 [95% CI, 0.645–0.942]; P < 0.01; median survival, 14.5 months vs. 11.5 months) compared with those receiving single-agent docetaxel. Following the failure of docetaxel monotherapy, 35% of patients did not receive additional cytotoxic chemotherapy. Among patients randomized to single-agent docetaxel, only those given poststudy single-agent capecitabine had significantly prolonged survival compared with those given any other poststudy chemotherapy (HR, 0.500; P = 0.0046; median survival, 21.0 months vs. 12.3 months, respectively). By contrast, poststudy vinorelbine-containing chemotherapy did not affect survival following progression on single-agent docetaxel compared with other poststudy chemotherapy regimens (HR, 1.014; P = 0.94; median survival, 13.5 months vs. 12.6 months, respectively). Among patients randomized to combination therapy, discontinuing docetaxel of capecitabine has a similar effect on survival (HR, 0.720; P = 0.20; median survival, 15.8 months vs. 18.3 months, respectively). Median survival was 18.3 months in patients who discontinued docetaxel and continued to receive capecitabine versus 15.8 months in patients who discontinued capecitabine and continued to receive docetaxel, with a trend toward improved survival in patients continuing to receive capecitabine. Although this is a retrospective analysis, these data suggest that the sequential administration of docetaxel followed by capecitabine is associated with prolonged survival in patients who are candidates for sequential single-agent therapy.