Clinical Efficacy and Safety of Baricitinib in Patients With Alopecia Areata in Korea.

BACKGROUND: Baricitinib is an oral Janus kinase 1 and 2 inhibitor that has shown significant efficacy in phase 3 trials for alopecia areata (AA). However, real-world data on its use for AA remain limited. OBJECTIVE: This study evaluated the efficacy and safety of baricitinib in Korean patients with AA. METHODS: In this retrospective multicenter study, 117 patients with AA received oral baricitinib 4 mg daily for at least 36 weeks. Patient demographics, Severity of Alopecia Tool (SALT) scores, and adverse events were assessed. RESULTS: SALT scores significantly decreased from baseline at all time points (p<0.001). By week 36, 55.4% of patients with a baseline SALT score >50 and 48.9% with a baseline score >95 achieved a SALT score of 20 or less. Notably, in Group A (baseline SALT score between 50 and 100) by week 36, the percentages for SALT 75, SALT 90, and SALT 100 were 52.0%, 44.0%, and 22.7%, respectively, while in Group B (baseline SALT score ≤50), the percentages were 81.0%, 66.7%, and 54.8%, respectively. Group B showed a significantly greater mean percentage improvement in SALT scores compared to Group A (p<0.001, Welch's t-test). Repeated measures analysis of variance further revealed that both group and time had significant effects on treatment response (p<0.001). Adverse reactions were mostly mild to moderate in severity and resolved with appropriate management. CONCLUSION: Baricitinib was well tolerated and resulted in clinical improvement among patients with AA in a real-world clinical setting. Baricitinib is a potential treatment option for patients with treatment-resistant AA.