Cemiplimab’s mechanism of action

Cemiplimab (Cemiplimab) is a recombinant human immunoglobulinG4 (IgG 4) monoclonal antibody that can bind to PD-1 and block its interaction with PD-L1 and PD-L2, releasing the suppression of immune responses mediated by the PD-1 pathway, including anti-tumor immune responses. In syngeneic mouse tumor models, blocking PD-1 activity resulted in decreased tumor growth. The PD-1 ligands PD-L1 and PD-L2 bind to the PD-1 receptor found on T cells and inhibit T cell proliferation and cytokine production. Upregulation of PD-1 ligand occurs in some tumors, and signaling through this pathway may contribute to suppression of active T cell immune surveillance of tumors.