Jonstam K, et al. - As dupilumab, a fully human monoclonal antibody targeting the interleukin-4 receptor α (IL-4Rα) subunit, is demonstrated to have efficacy and acceptable safety in chronic rhinosinusitis with nasal polyposis (CRSwNP) and other type 2 diseases (eg, atopic dermatitis and asthma), researchers examined its local effects on type 2 inflammatory biomarkers in nasal secretions and nasal polyp tissues of patients with CRSwNP in a randomized, placebo-controlled, phase 2 trial. Using immunoassay techniques, they measured cytokines, chemokines, and total immunoglobulin E (IgE) levels in nasal secretions and nasal polyp tissue homogenates of CRSwNP patients receiving dupilumab 300 mg or placebo weekly for 16 weeks. Nasal secretions and polyp tissues of patients with CRSwNP displayed reduction in multiple biomarkers of type 2 inflammation in correlation with dupilumab treatment, demonstrating that antagonism of IL-4Rα signaling suppresses IL-4-/IL-13-dependent processes, such as mucosal IgE formation, as well as the expression of chemokines attracting inflammatory cells to the nasal mucosa.