ONC206 for Treatment of Newly Diagnosed, Recurrent Diffuse Midline Gliomas, and Other Recurrent Malignant CNS Tumors

This trial tests an experimental drug called ONC206 for children and young adults with a rare and aggressive brain tumor called diffuse midline glioma (DMG), as well as other hard-to-treat brain and spinal cord cancers that have come back after prior treatment. **You may be eligible if...** - You are 2 years of age or older (some parts of the study require age 2–21) - You have been diagnosed with DMG with a specific genetic change (H3K27 alteration) and completed at least one prior treatment including radiation - OR you have another type of recurrent brain or spinal cord tumor that has not responded to standard treatments - You completed radiation 4–14 weeks before enrolling **You may NOT be eligible if...** - You have not yet completed radiation therapy or started other post-radiation treatments - You have significant organ problems or active serious infections - Your tumor is not in the brain or spinal cord Talk to your doctor to see if this trial is right for you.