Definition of Biological response modifiers

Biological response modifiers (BRMs): Substances that stimulate the body's response to infection and disease. The body naturally produces small amounts of these substances. Scientists can produce some of them in the laboratory in large amounts for use in treating cancer, rheumatoid arthritis, and other diseases.

BMRs used in biological therapy include monoclonal antibodies, interferon, interleukin-2 (IL-2), and several types of colony- stimulating factors (CSF, GM-CSF, G-CSF). Interleukin-2 and interferon are BRMs being tested for the treatment of advanced malignant melanoma. Interferon is a BRM now in use to treat hepatitis C.

The side effects of BRM therapy often include flu-like symptoms such as chills, fever, muscle aches, weakness, loss of appetite, nausea, vomiting, and diarrhea. Some patients develop a rash, and some bleed or bruise easily. Interleukin therapy can cause swelling. Depending on the severity of these problems, patients may need to stay in the hospital during treatment. These side effects are usually short-term and go gradually away after treatment stops.