Paclitaxel and doxorubicin in metastatic breast cancer

For the past decades the anthracyclines have been regarded as among the most active drugs for the treatment of metastatic breast cancer. However, the 5-year survival rate in patients with stage IV breast cancer continues to be below 20%, and new active drugs and drug combinations clearly must be explored. Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) has been demonstrated to be highly effective in treating patients with advanced breast cancer, including those with anthracycline-resistant breast cancer, a fact that has led to efforts to combine paclitaxel and anthracyclines. Several studies aiming to define the optimal dose and schedule of combination paclitaxel/doxorubicin have now been completed or are ongoing. Phase I/II studies have yielded encouraging preliminary response rates but quite variable toxicity profiles depending on the schedule used. These clinical trials involving combination paclitaxel/doxorubicin are reviewed, with special emphasis on the short-infusion trials.