OBJECTIVES:~Determine the maximum tolerated dose and dose-limiting toxicity of imatinib mesylate and vatalanib when administered with hydroxyurea in patients with recurrent or relapsed grade 3 or 4 malignant glioma.~Determine the safety and tolerability of this regimen in these patients.~Determine the single-dose and repeated-dose pharmacokinetic profiles of imatinib mesylate (in serum) and vatalanib in these patients.~Determine the pre- and post-treatment antiangiogenic effects of this regimen in these patients, using dynamic contrast-enhanced MRI to evaluate changes in the extent of vascular permeability, perfusion, and relative tumor blood volume.~Determine whether changes in diffusion-weighted images MRI (quantitated by apparent diffusion coefficient maps) correlate with tumor cellularity and tumor cell death in patients treated with this regimen.~Determine antitumor activity of this regimen, in terms of radiographic response, progression-free survival, and overall survival, in these patients.~OUTLINE: This is an open-label, dose-escalation study of imatinib mesylate and vatalanib.~Patients receive oral vatalanib once daily, oral imatinib mesylate once daily, and oral hydroxyurea twice daily on days 1-28*. Treatment repeats every 28 days in the absence of disease progression or unacceptable toxicity.~NOTE: *Patients receive vatalanib alone daily on days 1-7 followed by vatalanib, imatinib mesylate, and hydroxyurea on days 8-35 in course 1 only.~Cohorts of 3-6 patients receive escalating doses of imatinib mesylate and vatalanib until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose preceding that at which 2 of 3 or 2 of 6 patients experience dose-limiting toxicity. At least 6 patients are treated at the MTD.~After completion of study treatment, patients will be evaluated for 28 days.~PROJECTED ACCRUAL: A total of 42 patients will be accrued for this study.
RATIONALE: Imatinib mesylate, vatalanib, and hydroxyurea may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Vatalanib may also stop the growth of tumor cells by blocking blood flow to the tumor. Giving imatinib mesylate and vatalanib together with hydroxyurea may kill more tumor cells.~PURPOSE: This phase I trial is studying the side effects and best dose of imatinib mesylate and vatalanib when given together with hydroxyurea in treating patients with recurrent or relapsed malignant glioma.