Erlotinib in Treating Patients With Progressive Glioblastoma Multiforme

OBJECTIVES: Primary * Determine the maximum tolerated dose of erlotinib hydrochloride when administered in escalating doses every 72 hours in patients with progressive glioblastoma multiforme. Secondary * Determine the relationship between plasma and cerebrospinal fluid (CSF) concentrations of erlotinib hydrochloride in these patients. * Determine the relationship between plasma and CSF concentrations of erlotinib hydrochloride in patients not receiving concurrent enzyme-inducing antiepileptic drugs (EIAEDs) vs those receiving concurrent EIAEDs. * Correlate CYP3A4 activity, as measured by midazolam hydrochloride clearance, with plasma clearance of erlotinib hydrochloride in these patients. * Correlate CYP1A2 activity, as measured by the 4-hour paraxanthine (17X)/caffeine (137X) plasma ratio, with plasma clearance of erlotinib hydrochloride in these patients. * Determine, preliminarily, objective response and disease progression in patients treated with erlotinib hydrochloride. * Correlate the presence of EGFRvIII mutation with objective response and disease progression in patients treated with erlotinib hydrochloride. OUTLINE: This is an open-label, dose-escalation study. Patients are stratified according to use of concurrent enzyme-inducing antiepileptic drugs (EIAEDs) (yes vs no). Patients receive oral erlotinib hydrochloride once every 72 hours for 28 days. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity. Cohorts of 3-6 patients receive escalating doses\* of erlotinib hydrochloride until the maximum tolerated dose (MTD) is determined or preliminary results show no direct relationship between plasma and cerebrospinal fluid concentrations. The MTD is defined as the dose preceding that at which 2 of 3 or 2 of 6 patients experience dose-limiting toxicity. NOTE: \*Interim enrollment of patients is allowed; these patients receive the current approved dose of erlotinib hydrochloride. Patients undergo blood sample collection periodically on day 13 for pharmacokinetic studies. The pharmacokinetic study comprises midazolam hydrochloride and caffeine clearance assessment and correlation of these assessments with CYP3A4 activity and CYP1A2 activity. Paraffin-embedded and frozen tumor tissue is obtained from patients who underwent prior surgical resection for analysis of wild-type EGFR and EGFRvIII mutation by immunohistochemistry. Quality of life is assessed at baseline and then at 1 month and 6 months. After completion of study therapy, patients are followed periodically.