Docetaxel and cyclophosphamide in patients with advanced solid tumors

This trial was designed to determine the recommended maximum tolerated dose (MTD), toxicity, pharmacokinetics, and efficacy of docetaxel (Taxotere) and cyclophosphamide (Cytoxan, Neosar) for phase II studies. Both drugs were administered to 39 patients with advanced solid tumors, 26 of whom had breast cancer. Docetaxel doses ranged from 60 to 85 mg/m2 and cyclophosphamide doses ranged from 600 to 800 mg/m2. All patients received steroid prophylaxis. The MTDs for patients with a history of prior chemotherapy were 75 mg/m2 of docetaxel and 700 mg/m2 of cyclophosphamide. For patients with no prior chemotherapy, the MTDs were 75 mg/m2 of docetaxel and 800 mg/m2 of cyclophosphamide. The dose-limiting toxicity was neutropenic fever, observed in 41% of patients and 13% of cycles. Addition of granulocyte colony-stimulating factor (G-CSF, filgrastim [Neupogen]) did not permit further dose escalation, although it did result in briefer periods of neutropenia.