For almost two decades, the clinical impression has been that weekly taxanes, Taxol and Taxotere, are better tolerated if given at a reduced weekly dose. Weekly paclitaxel is FDA approved; or, at least, the FDA indication does not exclude the weekly schedule: for the treatment of breast cancer after failure of combination chemotherapy for metastatic disease or relapse within 6 months of adjuvant chemotherapy. Prior therapy should have included an anthracycline unless clinically contraindicated but the FDA does not appear to absolutely insist on a prior antracycline treatement.
There are now several studies for metastatic breast cancer that confirm that weekly administration is of similar effectiveness to every three week single agent pacltaxel but less toxic. In the adjuvant setting, a randomized clinical trial showed that weekly doses of the drug paclitaxel (Taxol®) following surgery and standard chemotherapy improves disease-free and overall survival in women with breast cancer. For metastatic disease, NCCN lists both the three weekly and once weekly regimens on p. BINV-O, 2.
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