cemiplimab + hypofractionated radiotherapy + granulocyte macrophage colony-stimulating factor + cyclophosphamide

This is a combination regimen of four distinct anticancer modalities: **cemiplimab**, an anti–PD-1 monoclonal antibody; **hypofractionated radiotherapy**, a high-dose, short-course radiation technique often used in oncology; **granulocyte macrophage colony-stimulating factor (GM-CSF)**, a cytokine that promotes myeloid cell proliferation and immune activation; and **cyclophosphamide**, an alkylating cytotoxic chemotherapy agent with immunosuppressant properties. The rationale for this regimen is to combine checkpoint inhibition (cemiplimab) to overcome tumor immune evasion, local tumor destruction and potential immune sensitization via hypofractionated radiotherapy, immune stimulation from GM-CSF, and immune modulation plus direct cytotoxicity from cyclophosphamide. This multi-modality approach aims to synergistically enhance anti-tumor immunity and may be tested in advanced cancers, where combination immunoradiotherapy regimens are investigated for potential efficacy.