Immune checkpoint inhibitors are a type of cancer treatment that help the body's immune system recognize and attack cancer cells. They work by blocking proteins, known as checkpoints, that normally keep immune responses in check. By inhibiting these proteins, the treatment enhances the immune system's ability to target and destroy tumors. These therapies have shown promise in treating various cancers, including melanoma, lung cancer, and bladder cancer. Some common immune checkpoint inhibitors include pembrolizumab and nivolumab. They are often used in combination with other treatments to improve patient outcomes and increase survival rates.