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Comparative Efficacy of JAK Inhibitors in Acute vs Nonacute Alopecia Areata: A Retrospective Cohort Study
Ruxin Ji1, Man Zhang1, Tian Tian1
1Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.
Abstract:
Despite advancements in systemic treatments, the efficacy of Janus kinase (JAK) inhibitors in acute versus non-acute alopecia areata (AA) remains poorly defined, necessitating comparative studies to optimize therapeutic strategies. This retrospective, single-centercentre cohort study included 158 AAalopecia areata patients treated with JAKJanus kinase inhibitors (tofacitinib or ritlecitinib) between 2021 and 2025, aimed at evaluating clinical outcomes and identifying predictors of super-responder (SR) status. Patients were stratified into acute (n=41) and non-acute (n=117) groups based on disease duration and treatment history, with efficacy assessed using the Severity of Alopecia Tool (SALT) through week 24. Our findings demonstrate that patients with acute AAalopecia areata achieved significantly superior outcomes, with 65 % reaching SALT100 by week 24 compared to 39.5 % in the non-acute group (p=0.041). Binary logistic regression analysis further identified tofacitinib treatment (OR=2.883, p=0.009) and mild-to-moderate baseline severity (OR=2.802, p=0.015) as significant predictors of SRsuper-responder status, while acute AAalopecia areata status showed borderline predictive value (OR=2.418, p=0.098). Although limited by its single-centercentre design and sample size, this study underscores that early intervention with JAKJanus kinase inhibitors in acute AAalopecia areata leads to enhanced hair regrowth, emphasizing the critical importance of timely clinical management.
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