There are currently 10 licensed biologic therapies for the treatment of rheumatoid arthritis in 2014. In this article, we review the risk of serious infection (SI) for biologic therapies. This risk has been closely studied over the last 15 years within randomised controlled trials, long-term extension studies and observational drug registers, especially for the first three antitumour necrosis factor (TNF) drugs, namely infliximab, etanercept and adalimumab. The risk of SI with the newer biologics rituximab, tocilizumab, abatacept and tofacitinib is also reviewed, although further data from long-term observational studies are awaited. Beyond all-site SI, we review the risk of tuberculosis, other opportunistic infections and herpes zoster, and the effect of screening on TB rates. Lastly, we review emerging opportunities for stratifying the risk. Patients can be risk-stratified based on both modifiable and non-modifiable patient characteristics such as age, co-morbidity, glucocorticoid use, functional status and recent previous SI.
The available armamentarium of biologic therapies for the treatment of rheumatoid arthritis (RA) has expanded rapidly in the last few years. The increasing number of therapies provides a welcome range of options for difficult-to-treat patients. Yet, as treatment options increase, it becomes more challenging to select the best option for a given patient. Clinicians are required to compare between treatment options, in terms of not only efficacy but also risk. One of the most notable risks with biologic therapy is the risk of infection. The aim of this review is to summarise and interpret the available evidence for the association between biologic therapies and the risk of infection, paying particular attention to comparative harms where possible. Topics within the review include a summary of currently available therapies and methods for monitoring drug safety. The evidence is then reviewed for all-site serious infection (SI), tuberculosis (TB), herpes zoster (HZ) and other opportunistic infections (OIs), and ending with risk stratification for the individual patient.