Dupilumab, an anti-IL-4Rα monoclonal antibody, suppresses type 2 inflammation by blocking dual signals, IL-4, and IL-13; it is expected to be effective in refractory eosinophilic airway inflammatory diseases, such as asthma and ECRS, as a new treatment option in place of systemic corticosteroids (SCS) [6–8]. The gene discussed is IL4R; the disease is asthma.