Dupilumab (REGN668/SAR231893), produced by a collaboration between Regeneron and 
Sanofi, is a monoclonal antibody currently in phase III for moderate-to-severe 
asthma. Dupilumab is directed against the α-subunit of the interleukin (IL)-4 
receptor and blocks the IL-4 and IL-13 signal transduction. Areas covered: 
Pathophysiological role of IL-4 and IL-13 in asthma; mechanism of action of 
dupilumab; pharmacology of IL-4 receptor; phase I and phase II studies with 
dupilumab; regulatory affairs. Expert opinion: Patients with severe asthma who 
are not sufficiently controlled with standard-of-care represent the target 
asthma population for dupilumab. If confirmed, efficacy of dupilumab in both 
eosinophilic and non-eosinophilic severe asthma phenotype might represent an 
advantage over approved biologics for asthma, including omalizumab, mepolizumab, 
and reslizumab. Head-to-head studies to compare dupilumab versus other biologics 
with different mechanism of action are required. Pediatric studies with 
dupilumab are currently lacking and should be undertaken to assess efficacy and 
safety of this drug in children with severe asthma. The lack of preclinical data 
and published results of the completed four phase I studies precludes a complete 
assessment of the pharmacological profile of dupilumab. Dupilumab seems to be 
generally well tolerated, but large studies are required to establish its 
long-term safety and tolerability.