IL4 and chronic rhinosinusitis with nasal polyps: Previously, dupilumab, which is a dual inhibitor of IL4 and IL13 signaling and controls the type 2 inflammation, was shown to decrease several symptoms of CRSwNP despite the diversity in the degree of eosinophilic infiltration of sinonasal tissue by classifying CRSwNP into the categories from nonECRS to severe ECRS [25].