Pharmacological approaches to target type 2 cytokines in asthma

Asthma is the most common chronic lung disease, affecting more than 250 million people worldwide. The heterogeneity of asthma phenotypes represents a challenge for adequate assessment and treatment of the disease. However, approximately 50% of asthma patients present with chronic type 2 inflammation initiated by alarmins, such as IL-33 and thymic stromal lymphopoietin (TSLP), and driven by the T_H2 interleukins IL-4, IL-5 and IL-13. These cytokines have therefore become important therapeutic targets in asthma. Here, we discuss current knowledge on the structure and functions of these cytokines in asthma. We review preclinical and clinical data obtained with monoclonal antibodies (mAbs) targeting these cytokines or their receptors, as well as novel strategies under development, including bispecific mAbs, designed ankyrin repeat proteins (DARPins), small molecule inhibitors and vaccines targeting type 2 cytokines.