IL5 and asthma: To date, the United States Food and Drug Administration (FDA) has approved six biologics for use in selected severe asthma patients: Omalizumab (anti-IgE); Mepolizumab, Benralizumab, Reslizumab (anti-IL5/anti-IL5Rα); Dupilumab (anti-IL4Rα); and Tezepelumab (anti-TSLP) (Guntern and Eggel, 2020).