IL5 and asthma: Therefore, because of the pivotal role played by IL-5 in the pathophysiology of T2-high asthma, this cytokine and its receptor represent key molecular targets for current biological therapies aimed to improve the control of severe and difficult-to-treat eosinophilic disease (Varricchi et al., 2016; Bagnasco et al., 2018a,b; McGregor et al., 2019; Siddiqui et al., 2019).