Therapeutic molecules are designed to target specific aspects of cancer cells, such as their growth, survival, and ability to metastasize. These include small molecules, monoclonal antibodies, and immune checkpoint inhibitors. For instance, Imatinib is a small molecule inhibitor used in the treatment of chronic myeloid leukemia (CML) by targeting the BCR-ABL fusion protein. Pembrolizumab is an immune checkpoint inhibitor that targets the PD-1 receptor, enhancing the immune system's ability to recognize and destroy cancer cells.