Miptenalimab (BI 754111) is a humanized monoclonal antibody targeting human lymphocyte-activation gene 3 (LAG-3/CD223). By specifically binding to LAG-3, the antibody blocks its interaction with ligands such as Major Histocompatibility Complex II (MHC II), thereby relieving the inhibitory signals on effector T cells and NK cells. As an immune checkpoint inhibitor, Miptenalimab is designed to reactivate exhausted T cells and enhance anti-tumor immune responses. Studies have demonstrated its synergistic potential when combined with PD-1 inhibitors (e.g., Ezabenlimab), leading to further elevated levels of cytokines like IFN-gamma.