Immunotherapy

Immunotherapy refers to treatments that utilize the body's immune system to fight disease. Rather than directly attacking disease cells with chemicals or radiation, immunotherapy aims to enhance or restore immune function so the body can recognize and destroy abnormal cells. It is used primarily in cancer but is also explored for infectious diseases, autoimmune conditions, and organ transplantation.

Common approaches include monoclonal antibodies that target specific molecules on cancer cells; checkpoint inhibitors that release brakes on T cells; cytokines such as interleukins or interferons to boost immune activity; adoptive cell transfer, including CAR-T cell therapy where a patient’s T cells are engineered to attack tumors; oncolytic viruses that infect cancer cells and stimulate an immune response; and vaccines designed to provoke immunity against tumor antigens or infectious agents.

In oncology, immunotherapy has yielded durable responses in some cancers that were previously hard to treat, often in combination with other therapies. CAR-T therapies have shown notable success in certain blood cancers, while checkpoint inhibitors have extended survival in several solid tumors. Immunotherapies are also investigated for chronic infections and as part of transplantation strategies to modulate immune reactions.

Side effects reflect immune system activation and can range from skin rashes and diarrhea to endocrine problems. Severe reactions such as cytokine release syndrome or immune-related adverse events may require specialized care. Not all patients respond, and benefits vary by cancer type, biomarker status, and prior treatments. Costs and access are ongoing considerations.

The field of immunotherapy developed rapidly in the 2010s and 2020s, with ongoing research to identify predictive biomarkers, expand approved indications, and minimize toxicities. Notable examples include PD-1/PD-L1 and CTLA-4 inhibitors, and CAR-T cell products.