IL4 and chronic rhinosinusitis with nasal polyps: An expanding number of biologics targeting T2 asthma (+/- comorbid CRSwNP) has already entered clinical practice showing clinical effectiveness in distinct (partly overlapping) inflammatory phenotypes/endotypes: anti-IgE (omalizumab), anti-IL5 (mepolizumab, reslizumab)/anti-IL5R (benralizumab), anti-IL4Rα (anti-IL4/IL-13; dupilumab), and only recently anti-alarmin TSLP (tezepelumab) [1,288].