A phase II study of docetaxel in paclitaxel-resistant ovarian and peritoneal carcinoma: A Gynecologic Oncology Group study

Objectives. Docetaxel is an inhibitor of microtubule depolymerization and has demonstrated activity in paclitaxel-resistant breast cancer and gynecologic cancer. The Gynecologic Oncology Group (GOG) conducted a study of docetaxel in paclitaxel-resistant ovarian and peritoneal carcinoma to determine its activity, and nature and degree of toxicity, in this cohort of patients. Methods. Patients with platinum- and paclitaxel-resistant ovarian or peritoneal carcinoma, defined as progression while on or within 6 months of therapy, were eligible if they had measurable disease and had not received more than one chemotherapy regimen. Docetaxel at a dose of 100 mg/m² was administered iv over 1 h every 21 days. A prophylactic regimen of oral dexamethasone 8 mg bid was begun 24 h before docetaxel administration and continued for 48 h thereafter. Hepatic function was strictly monitored. Results. Sixty patients were entered and treated with a total of 256 courses, with all 60 evaluable for toxicity and 58 evaluable for response. Responses were observed in 22.4% of patients, with 5.2% achieving complete response and 17.2% achieving partial response (95% CI, 12.5-35.3%). The median duration of response was 2.5 months. The likelihood of observing a response did not appear to be related to the length of the prior paclitaxel-free interval or duration of prior paclitaxel infusions. The principal adverse effect of grade 4 neutropenia occurred in 75% of patients. There was one treatment-related death. Dose reductions were required in 36% of patients. Conclusions. Docetaxel is active in paclitaxel-resistant ovarian and peritoneal cancer but, in view of significant hematologic toxicity, further study is warranted to ascertain its optimal dose and schedule.