Oval fluoropyrimidines among the new drugs for patients with metastatic breast cancer

Although drugs such as the taxoids and vinorelbine have increased the optio ns available for anthracycline-resistant metastatic breast cancer, new ther apeutic options are needed, particularly for taxoid-refractory tumours. Inc reasing emphasis is being placed on the development of oral agents, which m any patients prefer provided efficacy is not compromised, particularly ii t he oral agents are less toxic than current intravenous agents. Capecitabine , a new, oral fluoropyrimidine, mimics continuous infusion 5-FU and is acti vated preferentially at the tumour site. Phase II studies of capecitabine h ave demonstrated encouraging response rates in patients with few further tr eatment options (20% response with an additional 43% achieving stable disea se in paclitaxel-refractory patients; 36% response with a further 23% achie ving stable disease in anthracycline-refractory patients). In addition, a r andomized, phase II trial demonstrated a response rate of 30% (95% CI: 19-4 3%) with capecitabine as first-line treatment for metastatic breast cancer, compared with 16% (95% CI: 5-33%) in patients receiving low-dose CMF. Thes e trials also showed that capecitabine has a favourable safety profile typi cal of infused fluoropyrimidines. Both alopecia and myelosuppression were r are. Capecitabine may therefore provide an effective, well-tolerated and co nvenient alternative to intravenous cytotoxic agents, not only in taxoid-re sistant patients, but also in anthracycline-resistant metastatic breast can cer or as first-line therapy. Furthermore, the low incidence of myelosuppre ssion makes capecitabine an attractive agent for incorporation into combina tion regimens with agents such as epirubicin/doxorubicin, the taxoids and v inorelbine. (C) 2001 Cancer Research Campaign.