Lirilumab (also known as IPH-2102/BMS-986015) is a fully human monoclonal antibody that functions as an antagonist of killer cell immunoglobulin-like receptors (KIRs), specifically targeting the inhibitory receptors KIR2DL-1, -2, and -3 on natural killer (NK) cells and some T-cell subsets. By blocking these inhibitory KIRs, lirilumab prevents their interaction with their ligands (specific HLA-C allotypes) on tumor cells, thereby releasing the “brake” on NK cell activity. This aims to enhance NK cell-mediated killing of tumor cells, a mechanism known as “missing-self” recognition. It has been investigated clinically as an immuno-oncology agent, primarily in hematologic malignancies such as acute myeloid leukemia (AML) and multiple myeloma, often in combination with other therapies.