Docetaxel in combination with doxorubicin: a phase I dose-finding study

This phase I dose-finding study examined the effects of the combination of doxorubicin and docetaxel (Taxotere) in 42 women with metastatic breast cancer. The combination was studied at six different dosing levels. The maximum tolerated doses were defined as doxorubicin, 50 mg/m2, and docetaxel, 85 mg/m2, with sepsis as the dose-limiting toxicity. Activity was observed at all dose levels, especially at the highest dose levels (50/60, 50/75, 50/85, and 60/60 mg/m2), with a response rate of 81% (95%; confidence interval, 62.5% to 92.5%) in patients treated at these dose levels. The response rate in patients with visceral disease was 74%, and 82% in patients with liver metastasis. Adjuvant chemotherapy with or without anthracyclines did not affect the response rate. The recommended doses were doxorubicin, 50 mg/m2, and docetaxel, 75 mg/m2, or 60 mg/m2 of both drugs, administered on day 1 every 3 weeks, without granulocyte-colony stimulating factor (G-CSF, filgrastim [Neupogen]) support. Neutropenia was the only grade 3 or 4 adverse event. There were no cases of congestive heart failure, a significant decrease in left-ventricular ejection fraction, or interruption of treatment because of fluid retention.