Long-term persistence of baricitinib in alopecia areata: a real-world pharmacy-based cohort study.

Long-term baricitinib persistence in alopecia areata is not well defined. We performed a retrospective cohort study using hospital-pharmacy dispensing data from 77 patients. Discontinuation was defined as a gap of more than 90 days without medication coverage. Baseline Severity of Alopecia Tool (SALT) was available for 75/77 patients; follow-up SALT data were incomplete. Overall Kaplan-Meier persistence was 91.3% (95% confidence interval 81.6-96.0) at week 52, 75.1% (61.0-84.7) at week 104 and 68.7% (52.8-80.2) at week 130. Week-130 persistence was lower in patients with baseline SALT ≥95 than in those with SALT <95 (49.5% vs 82.3%; exploratory log-rank p=0.139). Chart-coded discontinuation reasons were heterogeneous and incomplete. Pharmacy-based persistence suggests durable real-world retention beyond 2 years.