Atovaquone Combined With Radiation in Children With Malignant Brain Tumors

This study tests atovaquone — a medicine normally used to treat parasitic infections — combined with standard radiation therapy in children with aggressive brain tumors (high-grade gliomas, including DIPG). Laboratory research suggests atovaquone may make tumors more vulnerable to radiation, and this trial will see if that holds true in children. **You may be eligible if...** - Your child has a newly diagnosed aggressive brain tumor (pediatric high-grade glioma, diffuse midline glioma, or DIPG) confirmed by imaging or biopsy - Your child weighs more than 10 kg - Your child has reasonable physical function (Karnofsky/Lansky score above 50%) - Seizures, if present, are stable for at least 7 days - Your child has adequate liver and kidney function **You may NOT be eligible if...** - Your child has already received cancer treatment for this tumor - Your child has severe liver or kidney problems - Your child has known allergies to atovaquone Talk to your doctor to see if this trial is right for you.