Chronic rhinosinusitis: Future treatments and unmet needs

Chronic rhinosinusitis (CRS) is an inflammatory disease of the nasal cavity and paranasal sinuses that affects 10% of the US population and presents with 2 major phenotypes: CRS with nasal polyps (CRSwNP) and CRS without nasal polyps (CRSsNP). Classification of CRS on the basis of specific pathobiologic mechanisms, also termed endotyping, finds that the type 2 endotype (characterized by cytokines such as IL-4, IL-5, and IL-13; tissue eosinophilia; and local IgE production) comprises 80% to 90% of patients with CRSwNP and 30% to 50% of patients with CRSsNP with severe disease requiring endoscopic sinus surgery (ESS) in Western countries. CRSwNP in Asia and CRSsNP have more endotypic heterogeneity, with significant subpopulations that have combinations of type 1 (IFN-gamma and IL-12), type 2, and type 3 (IL-17 and IL-22) inflammation.(1)