Safety of janus kinase inhibitors in patients with moderate-to-severe atopic dermatitis: a systematic review and meta-analysis of observational studies

INTRODUCTION: We conducted a systematic review and meta-analysis to evaluate real-world safety outcomes associated with Janus kinase (JAK) inhibitors in patients with moderate-to-severe atopic dermatitis (AD). METHODS: PubMed, Embase, Cochrane Library, and CINAHL were searched through April 2025. Two independent reviewers screened studies and extracted data according to predefined criteria. Risk of bias was assessed using Agency for Healthcare Research and Quality tools. RESULTS: The pooled incidence rates of adverse events (AEs) and serious adverse events (SAEs) with JAK inhibitors were 0.42 (95% CI: 0.35-0.50) and 0.03 (95% CI: 0.01-0.05), respectively. The most common AEs included acne (effect size [ES] = 0.14, 95% CI: 0.12-0.16), skin and subcutaneous tissue infections (ES = 0.17, 95% CI: 0.09-0.26), and herpes virus infections (ES = 0.07, 95% CI: 0.06-0.09). Compared with anti - interleukin-4/interleukin-13 inhibitors, JAK inhibitors were associated with higher risks of acne, anemia, and creatine kinase elevations. CONCLUSIONS: AEs were common but predominantly mild to moderate. Infections, particularly skin and subcutaneous tissue and herpes virus infections, were among the most frequently reported events. The pooled incidence of SAEs, including cardiovascular events, was low within reported follow-up periods. However, heterogeneity and relatively short follow-up limit conclusions regarding long-term risk. PROTOCOL REGISTRATION: CRD42025634423.