Tuberculosis and interleukin blocking monoclonal antibodies: Is there risk?

Several new monoclonal antibodies that interfere with interleukin (IL) cascades have come to market in recent years. They follow a generation of drugs that block tumor necrosis factor (TNF). It has been well established that TNF is important in the containment of Mycobacterium tuberculosis (Mtb) and that blocking this cytokine increases the risk of tuberculosis (TB) infection. Thus, judicious screening for Mtb of patients taking TNF blocking drugs has been the standard of care. It remains unclear if the newer monoclonal, interleukin blocking drugs, which affect IL-12, IL-23, and IL-17 pathways are associated with risk of Mtb reactivation. Herein we discuss what is known about the immunologic response to Mtb and discuss the data that is currently available for the new interleukin monoclonal antibody blocking medications regarding the risk of latent TB reactivation or active TB infection.