What is Immunotherapy

Immunotherapy is the term used to describe treating cancers and other diseases by making use of the body's natural defenses; rather than using poisons to kill cells (Cytotoxic therapy, Chemotherapy)

Antibodies that mimic human proteins can be made in bacterial cells, injected into patients and directed to attach to the surface of cancer cells. There they can either damage cells directly, or cause the patient’s immune cells to recognize and kill the cancer. Some examples are rituximab which targets lymphoma cells; and Trastuzumab which targets breast cancer cells. Some antibodies can be attached to cellular poisons and deliver them directly to cancer cells. These agents are called antibody-drug conjugates (ADC’s). Examples include TDM-1 used in breast cancer and Brentuximab used in Hodgkin lymphoma.

Checkpoint Inhibitors

Checkpoint inhibitors are drugs that stop cancers from hiding from the immune system; or from turning the immune system off. These drugs facilitate our own T-cells’ destruction of cancer. Some examples include Ipilimumab, nivolumab, pembrolizumab; used in melanoma, kidney cancers, and lung cancer. Combinations of these drugs and others with other immune agents and standard chemotherapy are being increasingly explored.

Cytokines- proteins that direct the immune system, can be injected as a primary treatment strategy or to enhance effects of other treatment strategies. Examples include Interferons and various Interleukins.

Vaccine therapy is currently in use for melanoma and is being looked at experimentally in a number of neoplasms including gynecologic tumors.

Human immunoglobulins ( blood product composed of antibodies) are used in certain blood conditions, to improve red cell counts and platelet counts. They may also be used to reduce infection risk in immunocompromised patients. Horse and rabbit antibodies may also have a role to play in special settings.

Cellular therapy is an important component in the fight against cancer. Read about this topic in a separate section.