Enzastaurin in Treating Young Patients With Refractory Primary CNS Tumors

Participants receive 200, 260, 340, or 440 mg/m2/day of enzastaurin orally once daily for 28 days (one course) during the dose escalation phase of the study. To study the toxicity profile of the MTD or phase II recommended dose established during the dose escalation phase, participants receive twice daily doses of enzastaurin orally at the phase II recommended dose for 28 days (one course). In the absence of unacceptable toxicity or disease progression, treatment may continue for 13 courses (approximately one year).