What is Biologics?

Biologics are genetically engineered proteins derived from human genes. They are designed to either inhibit or supplement specific components of the immune system called cytokines. These cytokines play a pivotal role in either fueling or suppressing inflammation (a key component in several forms of arthritis, such as rheumatoid arthritis and psoriatic arthritis).

In recent years, there have been promising advances in treating rheumatoid arthritis -- especially for those people who do not respond to disease-modifying drugs. The most important advance has been the development of a group of drugs called biologic response modifiers or biologics.

What makes these biologics so different from other drugs used to treat rheumatoid arthritis that modify the immune system is that they affect a specific component of the immune system, not the entire immune system. Thus, these medications theoretically have fewer side effects. Enbrel, Humira, and Remicade (Revelex in South Africa) inhibit a cytokine called tumor necrosis factor or TNF. Kineret blocks the cytokine interleukin-1 (or IL-1). Rituxan selectively targets immune cells known as CD20-positive B cells.

Biologics are unique in their action from other drugs because they affect only one aspect of the immune system, while other drugs will change the entire system process. The theory is that the drugs will therefore have far fewer side effects or ill effects than a medication that is broader in its affect.