The Efficacy and Safety of Low-dose Radiotherapy Combined With Sintilimab and Temozolomide in Recurrent Glioblastoma

This trial is testing a combination of low-dose radiation therapy, sintilimab (an immunotherapy checkpoint inhibitor), and temozolomide (a chemotherapy drug) for patients with glioblastoma — the most aggressive form of brain cancer — that has come back after initial treatment. **You may be eligible if...** - You are 18 or older with a confirmed glioblastoma recurrence (by imaging or biopsy) - It has been at least 12 weeks since your last course of radiation therapy - Your general health score (Karnofsky) is 60 or above - Your expected survival is more than 3 months - Your blood counts, kidney, and liver function are within acceptable ranges **You may NOT be eligible if...** - You require high-dose corticosteroids (more than 10 mg prednisone per day) - You have another active cancer in the past 5 years (with limited exceptions) - You have uncontrolled heart disease (heart failure NYHA class II or above, unstable angina, recent heart attack) - You have an active autoimmune disease (e.g., autoimmune colitis, hepatitis, lung inflammation) - You have HIV, or a history of immunodeficiency Talk to your doctor to see if this trial is right for you.