IL4 and asthma: Whilst having achieved greatly beneficial clinical effects with biological treatment, as research in severe asthma progressed, further drugs were introduced by FDA, including: benralizumab (which targets IL-5R α subunit), dupilumab (which inhibits IL-4 and IL-13 signaling) and reslizumab (anti-IL-5 antibody) (56, 70, 71).