Efficacy and safety of JAK inhibitors in the treatment of alopecia areata in children: a systematic review and meta-analysis

Background Alopecia areata (AA) is a non-scarring hair loss mediated by T lymphocytes. Recently, a growing number of studies have shown that Janus kinase inhibitors are effective in the treatment of AA in children. Methods A systematic review and meta-analysis were performed according to the PRISMA guidelines. Good response was defined as more than 50% decrease in Severity of Alopecia Tool (SALT) score or complete regrowth or more than 50% regrowth. Partial response was defined as 5-50% decrease in SALT score. Any response to treatment was defined as more than 5% in SALT score decrease. Results There were 81.9% responders, 68.5% good responders, and 7.7% partial responders among the 10 included studies. The treatment duration was longer in good responders than in partial responders (p = .009). Oral route was linked to a better response to topical medication, with an odds ratio of 7.8 (95%CI 1.655-36.76). In terms of toxicity, reported adverse events included only mild symptoms. Liver transaminase elevation, upper respiratory tract infection, and eosinophilia were the most common adverse events. Conclusions Janus kinase inhibitors demonstrated promise in the treatment of AA in children, with the most common side effects being minor and reversible.