Immunotherapy, also known as biological therapy or biotherapy, encompasses a diverse set of therapeutic strategies that harness or modify the immune system to prevent, control, or eliminate disease. In its narrowest definition, immunotherapy refers to treatments designed to stimulate or guide the immune system to recognize and fight cancer, often by enhancing or restoring immune responses to eradicate malignant cells while sparing healthy tissue.
A broader definition of immunotherapy applies beyond oncology, including strategies to stimulate or suppress immune activity against other diseases such as autoimmune disorders, infectious diseases, and allergies. These approaches may involve vaccines, immune modulators, or monoclonal antibodies designed to alter immune responses, either to boost protection against pathogens or to reduce damaging inflammation.