ORLANDOAdding capecitabine (Xeloda) to docetaxel (Taxotere) (XT)
significantly improves response rates, time to progression, and overall
survival, compared with docetaxel alone in patients with metastatic breast
cancer, according to results of a phase III study of the combination.
Lead investigator Joyce O’Shaughnessy, MD, co-director of breast cancer
research at Baylor-Sammons Cancer Center and US Oncology, Dallas, updated
the results of the trial at an industry-sponsored symposium held in
conjunction with the 38th Annual Meeting of the American Society of Clinical
Oncology. The study findings were recently published in the Journal of
Clinical Oncology (20:2812-2823, 2002).
"The capecitabine/docetaxel combination is the first cytotoxic
combination that has been shown to have a survival advantage over
single-agent docetaxel," Dr. O’Shaughnessy commented. "Both
drugs are very active single agents, and I would argue that they are two of
the very few cytotoxic agents we have that can impact the natural history of
metastatic breast cancer."
Dr. O’Shaughnessy noted that the two agents have distinct mechanisms of
action and limited overlap of toxicities. Moreover, taxanes further
upregulate thymidine phosphorylaseand thus promote the tumor-selective
accumulation of fluorouracil (5-FU)and capecitabine/taxane combinations
have shown clear synergistic activity in preclinical studies.
In the phase III trial of the capecitabine/docetaxel combination, 511
anthracycline-pretreated women with measurable metastatic breast cancer were
randomized to receive either full-dose docetaxel (100 mg/m² on day 1) or 75
mg/m² of docetaxel on day 1 and full-dose capecitabine (1,250 mg/m² bid on
days 1 to 14, with 7 days off).