In contrast, another IL-4Rα monoclonal antibody (mAb) REGN668 (Dupilumab/SAR231893) developed by Regeneron (Tarrytown, USA) in collaboration with Sanofi (Paris, France) revealed clinical efficacy in reducing asthma exacerbations, improving lung function and symptom control in patients with persistent moderate to severe eosinophilic asthma and is currently in a phase-III clinical trial (NCT02414854) [19]. The gene discussed is IL4R; the disease is asthma.