Combination of Tarlatamab and Temozolomide in Patients With Central Nervous System Tumors

This study is testing whether combining tarlatamab (an immunotherapy drug that targets DLL3, a protein found on certain brain tumor cells) with temozolomide (a chemotherapy commonly used for brain tumors) can help patients with high-grade brain tumors that have come back or stopped responding to standard treatment. **You may be eligible if...** - You are 12 years or older with a confirmed diagnosis of a high-grade brain tumor (such as IDH-mutant high-grade glioma or other aggressive central nervous system tumors) - Your tumor expresses the DLL3 protein (confirmed by lab testing on a tissue sample) - Your tumor has progressed or is not responding after at least one prior treatment including radiation therapy - You have no remaining effective standard treatment options - You have measurable or evaluable disease **You may NOT be eligible if...** - Your tumor does not express DLL3 - You have not received prior radiation therapy as part of treatment - You have other serious medical conditions that make you ineligible per the study team Talk to your doctor to see if this trial is right for you.