Safety Profile of Baricitinib in Patients With Severe Alopecia Areata: A Prospective Study

Introduction: In adults, baricitinib, a Janus kinase (JAK)1/JAK2 inhibitor, is the first globally approved treatment for severe alopecia areata (AA). Its efficacy and safety were established in phase III trials, but real-life evidence remains limited. Objective: Our aim was to evaluate the real-life safety profile of baricitinib over 48 weeks in a clinical setting. Methods: A prospective observational study was conducted on 87 adult patients with severe AA at the University Hospital of Turin. Patients were treated with baricitinib at doses of 2 or 4 mg daily and were evaluated at baseline, 12, 24, 36, and 48 weeks. Adverse events (AEs) were carefully monitored, and disease severity was measured using the Severity of Alopecia Tool (SALT) score. Results: The cohort consisted of 71% females, with a mean age of 42 years and a mean baseline SALT score of 76.9. Baricitinib was generally well tolerated, with 20% of patients reporting AEs. The most common AEs were hypercholesterolemia (17%), hypertriglyceridemia (9.2%), and upper respiratory tract infections (5%). Two patients discontinued treatment due to neutropenia and recurrent infections. Most AEs were mild and manageable. Conclusion: Baricitinib shows a favorable safety profile in real-life clinical settings, aligning with findings from controlled clinical trials. The results support its use in routine clinical practice, though larger prospective studies are needed for further confirmation.