SCH 66336 in Treating Children With Recurrent or Progressive Brain Tumors

DISEASE CHARACTERISTICS: Histologically confirmed recurrent or progressive (refractory) brain tumors Histologic confirmation waived for brainstem gliomas Bone marrow involvement allowed if transfusion independent PATIENT CHARACTERISTICS: Age: 21 and under Performance status: Lansky 60-100% OR Karnofsky 60-100% Life expectancy: More than 8 weeks Hematopoietic: See Disease Characteristics Absolute neutrophil count greater than 1,000/mm^3 Platelet count greater than 75,000/mm^3 Hemoglobin greater than 9 g/dL Hepatic: Bilirubin no greater than upper limit of normal SGPT and SGOT less than 2.5 times normal Albumin greater than 3 g/dL PT/PTT no greater than 120% upper limit of normal No overt hepatic disease Renal: Creatinine no greater than 1.5 times normal OR Glomerular filtration rate greater than 70 mL/min No overt renal disease Cardiovascular: No overt cardiac disease Pulmonary: No overt pulmonary disease Other: Neurologic deficits allowed if stable for at least 1 week prior to study More than 3rd percentile weight for height Able to swallow pills No uncontrolled infection No known or suspected allergy to poloxamer 188, croscarmellose sodium, silicon dioxide, or magnesium stearate I Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception during and for up to 10 weeks after study PRIOR CONCURRENT THERAPY: Biologic therapy: More than 6 months since prior bone marrow transplantation More than 1 week since prior growth factors Chemotherapy: At least 3 weeks since prior myelosuppressive chemotherapy (6 weeks for nitrosoureas) and recovered Endocrine therapy: Concurrent dexamethasone allowed if on stable dose for at least 1 week prior to study Concurrent oral contraceptives or other hormonal contraceptive methods allowed Radiotherapy: More than 6 weeks since prior substantial bone marrow radiotherapy More than 3 months since prior craniospinal radiotherapy (more than 24 Gy) or total body irradiation More than 2 weeks since prior focal radiotherapy for symptomatic metastatic sites Surgery: Not specified Other: No concurrent enzyme-inducing anticonvulsant drugs No other concurrent anticancer or experimental drug therapy