Phase III randomized trials of docetaxel in patients with metastatic breast cancer

In a randomized phase III trial in which docetaxel was compared with doxorubicin in metastatic breast cancer patients who had failed prior alkylating chemotherapy, docetaxel proved more active, achieving responses at a significantly higher rate (complete + partial responses, 48% v 33%). The risk to benefit ratio favors docetaxel. The higher response rate was achieved without the risk of potentially fatal cardiac toxicity evident in patients who received doxorubicin and with a lower risk of infection and febrile neutropenia. In a second phase III study, patients with metastatic breast cancer who had failed prior anthracycline therapy were randomized to receive either docetaxel or a standard salvage regimen of mitomycin C plus vinblastine. Those assigned to docetaxel lived significantly longer (median survival, 11.4 v 8.7 months), experienced a longer time before disease progression (19 weeks v 11 weeks), and achieved a higher overall response rate (30% v 11.6%). The toxicity profile of both regimens was manageable. These phase III studies confirmed the activity observed with docetaxel in the phase II trials and support the view point that docetaxel is one of the most active agents available for the treatment of breast cancer.