Checkpoint inhibitors target specific proteins used by cancer cells to evade the immune system. The most common targets are PD-1 (Programmed Death-1), PD-L1 (Programmed Death-Ligand 1), and CTLA-4 (Cytotoxic T-Lymphocyte-Associated Protein 4). By inhibiting these proteins, the drugs enhance the immune system's ability to recognize and attack tumor cells. This mechanism, while effective, can also lead to immune-related adverse events (irAEs).
