Used in cancer immunotherapy to block the PD-1 receptor on T-cells, enhancing the immune system's ability to detect and destroy tumor cells. It is applied in treating various malignancies, including melanoma, non-small cell lung cancer, and other solid tumors. By inhibiting the PD-1 immune checkpoint pathway, it helps restore anti-tumor immune responses that cancer cells often suppress. Currently utilized in clinical trials and therapeutic regimens, often in combination with other immunotherapies or treatments like chemotherapy and radiation.