Pimivalimab (JTX-4014) is a high-affinity, fully human IgG4 monoclonal antibody targeting the cell surface receptor PD-1. By blocking the interaction between PD-1 and its ligands PD-L1 and PD-L2, the antibody reverses the immunosuppressed state of T cells and enhances the anti-tumor immune response against various solid tumors. It is frequently studied as a monotherapy or in combination with other therapies, such as LILRB2 inhibitors.