Phase I study of docetaxel in combination with cyclophosphamide as first-line chemotherapy for metastatic breast
1Department of Medical Oncology, Cancer Research UK, West of Scotland Clinical Trials Unit, Beatson Oncology Centre, E Block, Western Infirmary, Glasgow, G11 6NT, Scotland, UK. P.Vasey@beatson.gla.ac.uk
Abstract:
This phase I was study conducted to establish the maximum tolerated dose, dose-limiting toxicity, and recommended dose of docetaxel in combination with cyclophosphamide as first-line chemotherapy for metastatic breast cancer. Twenty-six patients were treated with cyclophosphamide (600 mg m(-2), intravenous bolus) followed by docetaxel (60, 75 or 85 mg m(-2), 1-h intravenous infusion) every 3 weeks. The maximum tolerated dose was docetaxel 85 mg m(-2) with cyclophosphamide 600 mg m(-2), the dose-limiting toxicity being febrile neutropenia. Grade 4 neutropenia was experienced by all patients, but was generally brief. Otherwise, the combination was well tolerated with few acute and no chronic non-haematological toxicities of grade 3/4. Activity was observed at all dose levels and disease sites, and the overall response rate was 42% (95% confidence interval 22-61%). The pharmacokinetics of docetaxel were not modified by cyclophosphamide coadministration. These findings establish a recommended dose of docetaxel 75 mg m(-2) in combination with cyclophosphamide 600 mg m(-2) every three weeks for phase II evaluation.
