Used in the treatment of various cancers by enhancing the body's immune response against tumor cells. It works by blocking the PD-1 receptor on T-cells, preventing tumors from evading immune detection. This antibody is particularly applied in immunotherapy regimens for solid tumors, including non-small cell lung cancer, melanoma, and other advanced or metastatic cancers. It helps restore T-cell activation and proliferation, leading to improved tumor cell clearance. Often used in combination with other checkpoint inhibitors or cancer treatments to increase therapeutic efficacy. Suitable for patients whose tumors express high levels of PD-L1 or show microsatellite instability.