Mechanisms of Smell Improvement With Dupilumab.

This study seeks to explore the mechanism through which dupilumab improves olfactory cleft inflammation in patients with chronic sinusitis with nasal polyps (CRSwNP). The investigators expect this study to provide convincing evidence that dupilumab improves clinical olfaction via direct reduction in olfactory cleft inflammation.

Inclusion Criteria: * Adults ≥18 years of age * Meet criteria for CRSwNP as defined by ICAR-21 * 2 out of 4 cardinal symptoms for ≥12 weeks * Visible evidence of inflammation on endoscopy or imaging * Bilateral visible nasal polyps ≥1 in each nasal cavity (0-4 scale each side) * Olfaction score ≥1 (0-3 scale) * Candidate for treatment with dupilumab for CRSwNP * Elected to proceed with dupilumab for treatment of CRSwNP Exclusion Criteria: * Prior use of dupilumab * Previous treatment with another biologic medication for CRSwNP or asthma within 6 months * Any nasal or sinus surgery within the last 3 months * Oral corticosteroid use within the last 1 month * Current pregnancy, breast-feeding, or plan to become pregnant during next 3 months * Presence of antrochoanal nasal polyps; acute rhinosinusitis; upper respiratory infection; * Allergic granulomatous angiitis/eosinophilic granulomatosis with polyangiitis; * Granulomatosis with polyangiitis; cystic fibrosis; Young syndrome; * Kartagener syndrome; or dyskinetic cilia syndrome * Poorly controlled asthma