Purpose: Taxol (paclitaxel; Bristol-Myers Squibb, Princeton, NJ) is a new antineoplastic drug with broad-spectrum activity in solid tumors, including epithelial ovarian cancer, head and neck cancer, esophageal cancer, breast cancer, bladder cancer, and lung cancer. Its unique mechanism of action, polymerization of tubulin monomers, has stimulated both clinical and preclinical research on this agent. As limited drug supplies became more plentiful, a phase II trial of Taxol was initiated in patients with advanced squamous cervix cancer who had received no prior chemotherapy.
Patients and methods: In this trial, 30 assessable patients were initially entered onto the study and four partial responses were seen. Further accrual of 22 assessable patients was then accomplished to define better the response rate with smaller confidence intervals. The starting dose of Taxol was 170 mg/m2 (135 mg/m2 for patients with prior pelvic radiation) given as a 24-hour continuous intravenous infusion with courses repeated every 3 weeks. Dose escalations to 200 mg/m2 and deescalations to 110 mg/m2 were allowed based on adverse effects.
Results: The final response rate was 17% (two complete responses and seven partial responses). The primary and dose-limiting toxicity was neutropenia.
Conclusion: The response rate makes Taxol a drug with sufficient activity to explore it in combination with other agents with similar activity.