Some of the most promising advances in cancer research in recent years involve treatments known as immunotherapy. These advances are spurring billions of dollars in investment by drug companies, and are leading to hundreds of clinical trials. Here are answers to some basic questions about this complex and rapidly evolving field.
Immunotherapy refers to any treatment that uses the immune system to fight diseases, including cancer. Unlike chemotherapy, which kills cancer cells, immunotherapy acts on the cells of the immune system, to help them attack the cancer.
Drugs called checkpoint inhibitors are the most widely used form of immunotherapy for cancer. They block a mechanism that cancer cells use to shut down the immune system. This frees killer T-cells — a critically important part of the immune system — to attack the tumor. Four checkpoint inhibitors have been approved by the Food and Drug Administration and are on the market. They are given intravenously.