Retifanlimab With or Without Difluoromethylornithine for the Treatment of Progressive High Grade Gliomas

This phase I/II trial tests the safety, side effects best dose and effect of retifanlimab with or without difluoromethylornithine (DFMO) for the treatment of high grade gliomas that are growing, spreading, or getting worse (progressive). Immunotherapy with monoclonal antibodies, such as retifanlimab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread. DFMO is in a class of medications called ornithine decarboxylase (ODC) inhibitors. It works by blocking the action of a substance that signals tumor cells to multiply. This helps stop or slow the spread of tumor cells. Giving retifanlimab with or without DFMO mat be safe, tolerable and/or effective in treating patients with progressive high grade glioma.