Backgroud
Biologic agents have been thought a new approach to improve atopic dermatitis (AD) therapeutics. But the clinical efficacy and safety of biologic agents in moderate to severe AD are poorly known. 

Objective
The aim of this study was to compare the benefits and harms of biologic agents versus placebo for AD patients with moderate to severe disease.

Method
In Feb 2019 we searched for randomized controlled trials (RCTs) in MEDLINE, Embase and web of science; and trials registers. We used standard Cochrane methods. The primary outcome was the Eczema Area and Severity Index (EASI)-75 response, while secondary outcomes were SCOring Atopic Dermatitis (SCORAD)-75, EASI-50, SCORAD-50, Investigator Global Assessment 0/1 responses, change in responses from baseline, and adverse events. We calculated odds ratios (OR) and mean differences (MD) along with 95% confidence intervals (CI) for meta-analysis. We converted OR to risk ratios (RR) for ease of interpretation.  

Results
We included 11 randomized controlled trials (RCTs) evaluating five biologic agents. High-quality evidence was available for dupilumab, nemolizumab and lebrikizumab. Pooling seven studies, at weeks 12–16 dupilumab 300 mg every week to every 2 weeks achieved EASI-75 responses of 54.9%, superior to placebo [relative risk (RR) 3.29, 95% confidence interval (CI) 2.93–3.69]. Nemolizumab had similar EASI-75 responses as placebo, but significantly improved pruritus. lebrikizumab demonstrated superior EASI-50 responses versus placebo (RR 1.18, 95% CI 0.94–1.49). In two RCTs each, omalizumab and ustekinumab were comparable with placebo. All medications had a comparable safety profile to placebo.

Conclusion
Dupilumab is currently the only biologic with robust evidence of efficacy in AD. Nemolizumab and lebrikizumab show promise but further data are needed. Longer follow-up and larger studies will establish their safety profile.

The clinical efficacy and safety of biologic agents for moderate to severe atopic dermatitis: a meta- analysis