Pain & Central Nervous System Week via NewsEdge :

2008 MAY 12 - (NewsRx.com) -- " This is a phase-I study of gefitinib in combination with temozolomide in patients with gliomas (see also Epilepsy). The goal of the study was to define the maximum tolerated dose (MTD) and to characterize the pharmacokinetics of gefitinib when combined with temozolomide," scientists in the United States report.

"Patients and methods Patients were stratified according to co-administration of enzyme-inducing anti-epileptic drugs (EIAEDs). There were 26 evaluable patients enrolled (16 on EIAEDs, 10 not on EIAEDs). All but seven patients had Glioblastoma Multiforme (GBM), and only six cases had a Karnosfsky Performance Status (KPS) of less than 80; median age was 51 years. All had received prior radiotherapy and 14 patients had no prior chemotherapy. The starting dose of temozolomide was 150 mg/m(2)/day for 5 days every 28 days and could be escalated to a maximum dose of 200 mg/m(2)/day in subsequent cycles. The starting dose of gefitinib was 500 mg/day given by mouth on a continuous basis. Dose-limiting toxicity was assessed in cycle one only. For patients on EIAEDs, the MTD of gefitinib was 1,000 mg/day in combination with temozolomide. Dose-limiting toxicity (DLT) was due to diarrhea, nausea and vomiting. For patients not on EIAEDs, the MTD was 250 mg/day in combination with temozolomide. The DLT was due to increases in liver transaminases. Rash was not a significant toxicity at these dose levels," wrote M.D. Prados and colleagues, University of California.

The researchers concluded: "The peak concentration and AUC(0-24hr) at the 500 mg dose level was 1.8 and 2.5-fold lower, respectively, in the EIAED group compared to the non-EIAED group; trough levels of gefitinib increased in both groups consistent with the reported terminal half-life ranging from 27 to 51 h. The recommended phase-2 dose of gefitinib when used in combination with temozolomide is 1,000 and 250 mg/day, respectively, for patients on or not on EIAEDs."

Prados and colleagues published their study in Cancer Chemotherapy and Pharmacology (Phase-1 trial of gefitinib and temozolomide in patients with malignant glioma: a North American brain tumor consortium study. Cancer Chemotherapy and Pharmacology, 2008;61(6):1059-1067).

For additional information, contact M.D. Prados, University of California, Dept. of Neurology Surgery, 400 Parnassus Avenue, Room 808, San Francisco, CA 94143, USA.

The publisher's contact information for the journal Cancer Chemotherapy and Pharmacology is: Springer, 233 Spring Street, New York, NY 10013, USA.

<>

Return to Epilepsy News