IL4 and asthma: Within such a therapeutic context, the fully human monoclonal antibody dupilumab binds to the IL-4 receptor and suppresses the bioactivities of both IL-4 and IL-13; this mechanism explains why dupilumab can effectively dampen type 2 inflammation and provide significant clinical benefits in severe asthma (Figure 1), atopic dermatitis and nasal polyposis (Figure 1) [25,26,27].