Dupilumab, a monoclonal antibody targeting the interleukin-4 receptor α (IL-4Rα), blocks the signalling of both IL-4 and IL-13, key mediators of the Th2 inflammatory axis involved not only in atopic dermatitis but also in the development of other allergic diseases such as asthma [38]. The gene discussed is IL4; the disease is atopic eczema.