Biologic agents, also known as biologics, are disease-modifying antirheumatic drugs (DMARDs) that were designed to prevent or reduce the inflammation that damages joints. Biologics target molecules on cells of the immune system, joints, and the products that are secreted in the joints, all of which can cause inflammation and joint destruction.
There are several types of biologics, each of which targets a specific type of molecule involved in this process. Biologics that bind tumor necrosis factor (TNF) include etanercept, adalimumab, infliximab, certolizumab pegol, and golimumab. These are called anti-TNF agents or TNF inhibitors. There are additional biologics that target other molecules instead of TNF such as abatacept, tocilizumab, rituximab, anakinra or tofacitinib. These are commonly used for people with arthritis that is not well-controlled with methotrexate and one of the anti-TNF agents.
Biologics are often reserved for people who have not completely responded to DMARDs or for those who cannot tolerate DMARDs in doses large enough to control inflammation. Unlike DMARDs, which can take six weeks or more to begin working, biologics tend to work more rapidly. Biologics may be used alone but, usually, they are combined with methotrexate.
All biologic agents must be injected except tofacitinib that can be used orally. Biologic agents should not be used in people with serious infections. Testing for tuberculosis (TB) is mandatory before starting anti-TNF therapy because there is an increased risk of developing active TB while receiving anti-TNF therapy.
Anti-TNF agents are neither recommended for people who have lymphoma or who have been treated for lymphoma in the past. Overall, in the short term (<5 years of treatment), biologics are considered to be safe. There is not consistent information regarding its toxicity beyond 10 years on treatment.