What Are Biologics?

Biologics are special types of disease-modifying antirheumatic drugs (DMARD). They are used to treat a wide range of health conditions. Biologics are usually injected or infused and work by targeting and suppressing specific segments of the immune system that perpetuate inflammation.

Types of biologics

Biologics used to treat autoimmune and inflammatory diseases, such as rheumatoid arthritis, Crohn’s disease, psoriasis, and systemic lupus erythematosus, include four main types:

1. Tumor necrosis factor inhibitors
   Tumor necrosis factor (TNF) is a protein produced by white blood cells that triggers inflammation. In autoimmune conditions, TNF triggers excessive inflammation. TNF inhibitors stop the disease process by blocking the activity of TNF. Examples of TNF inhibitors include etanercept, infliximab and adalimumab.
2. Interleukin inhibitors
   Interleukins are a type of cytokine, or protein, involved in inflammation. These proteins include Il-1, Il-6, Il-12, and Il-23. Examples of biologic interleukin inhibitors include anakinra (which blocks Il-1) and tocilizumab (which targets Il-6).
3. B-cell inhibitors
   B cells are a type of white blood cell that play a role in the body’s immune response. Biologics that target B cells reduce the activity of the immune system. Rituximab is a commonly prescribed B-cell inhibitor.
4. T-cell inhibitors
   T cells are also white blood cells. Targeting T cells reduces the activity of the immune system, therefore, decreasing inflammation.

Potential side effects

While biologics can reduce the inflammatory process, they also have potential side effects; some of which can be serious. Biologics are rarely prescribed in combination because the risks generally outweigh the benefits. Biologics may be used with two or more other non-biologic DMARDs to control inflammation. Common side effects of biologics include, but are not limited to, the following:

• Infusion or injection site reactions
• Fever, muscle aches and pains, headache
• Anemia
• Hypersensitivity reactions, including anaphylaxis and serum sickness
• Antibody production and drug-induced autoimmune conditions
• Decreased white blood cell counts
• Increased risk of serious infection
• Interstitial lung disease
• Cancers