IL4 and asthma: The current biologics for severe asthma treatment include omalizumab (anti-IgE), mepolizumab and reslizumab (anti-IL-5), benralizumab (anti-IL-5 receptor), dupilumab (anti-IL-4 receptor α, blocking both the IL-4 and IL-13 pathways), and tezepelumab (anti-TSLP).