Background: The primary objective of the current study was to determine the response rate of paclitaxel in patients with recurrent malignant glioma by using different doses dependent on the concomitant use of anticonvulsants. Secondary objectives were to determine the time period to treatment failure, to evaluate toxicities, and to obtain pharmacokinetic data.
Methods: Adult patients who had recurrent malignant glioma were treated with paclitaxel. Patients were treated at different doses depending on the concomitant use of anticonvulsants known to induce the p450 hepatic enzyme system. Patients on such agents were treated at a dose of 330 mg/m2, whereas those not on these anticonvulsants were treated at a dose of 210 mg/m2. Tumor response was assessed at 6-week intervals. Treatment was continued until documented tumor progression or unacceptable toxicity occurred, or a total of 12 paclitaxel infusions was completed.
Results: From January 1997 to June 1997, 23 patients were treated with paclitaxel. Four patients were ineligible for the current study. Of the 19 eligible patients, there were no responses seen. Four (21%) had stabilization of disease. Median time to treatment failure was 1 month (95% confidence interval [CI], 1-2 mos) and median survival was 7 months (95% CI, 6-10 mos). Three patients were removed from the current study because they had toxicity. Pharmacokinetic studies demonstrated that drug levels and clearance values were consistent with previously reported findings.
Conclusion: Even though higher doses were administered to patients who had recurrent malignant glioma and who were on concomitant anticonvulsants, there were no objective responses to paclitaxel. Time to tumor progression was 1 month. Further testing of paclitaxel at this dose schedule does not appear to be warranted in this patient population.