BACKGROUND: Dupilumab is a fully human anti-interleukin-4 receptor α monoclonal 
antibody that blocks both interleukin-4 and interleukin-13 signaling. Its 
effectiveness in reducing oral glucocorticoid use in patients with severe asthma 
while maintaining asthma control is unknown.
METHODS: We randomly assigned 210 patients with oral glucocorticoid-treated 
asthma to receive add-on dupilumab (at a dose of 300 mg) or placebo every 2 
weeks for 24 weeks. After a glucocorticoid dose-adjustment period before 
randomization, glucocorticoid doses were adjusted in a downward trend from week 
4 to week 20 and then maintained at a stable dose for 4 weeks. The primary end 
point was the percentage reduction in the glucocorticoid dose at week 24. Key 
secondary end points were the proportion of patients at week 24 with a reduction 
of at least 50% in the glucocorticoid dose and the proportion of patients with a 
reduction to a glucocorticoid dose of less than 5 mg per day. Severe 
exacerbation rates and the forced expiratory volume in 1 second (FEV1) before 
bronchodilator use were also assessed.
RESULTS: The percentage change in the glucocorticoid dose was -70.1% in the 
dupilumab group, as compared with -41.9% in the placebo group (P<0.001); 80% 
versus 50% of the patients had a dose reduction of at least 50%, 69% versus 33% 
had a dose reduction to less than 5 mg per day, and 48% versus 25% completely 
discontinued oral glucocorticoid use. Despite reductions in the glucocorticoid 
dose, in the overall population, dupilumab treatment resulted in a severe 
exacerbation rate that was 59% (95% confidence interval [CI], 37 to 74) lower 
than that in the placebo group and resulted in an FEV1 that was 0.22 liters (95% 
CI, 0.09 to 0.34) higher. Injection-site reactions were more common with 
dupilumab than with placebo (9% vs. 4%). Transient blood eosinophilia was 
observed in more patients in the dupilumab group than in the placebo group (14% 
vs. 1%).
CONCLUSIONS: In patients with glucocorticoid-dependent severe asthma, dupilumab 
treatment reduced oral glucocorticoid use while decreasing the rate of severe 
exacerbations and increasing the FEV1. Transient eosinophilia was observed in 
approximately 1 in 7 dupilumab-treated patients. (Funded by Sanofi and Regeneron 
Pharmaceuticals; LIBERTY ASTHMA VENTURE ClinicalTrials.gov number, NCT02528214 
.).