Real-World Assessment of Disease Characteristics and Clinical Outcomes in Alopecia Areata in a Global Noninterventional Observational Cohort (ADAAGIO)

Background and Objective Limited evidence exists on prevailing treatments, disease characteristics, and real-world outcomes of patients with alopecia areata (AA), particularly for those with ≥50% scalp hair loss (SHL). This study sought to address this evidence gap. Methods This was a retrospective chart review study in the United Kingdom, France, Spain, and Germany. Adults and adolescents with ≥50% SHL were included. First clinical observation of ≥50% SHL defined the study index (2015-2019). Patients had ≥6 months of follow-up from index. Analyses were descriptive. The primary endpoint was absolute Severity of Alopecia Tool (SALT) score, assessed longitudinally. Sustained SALT≤20, assessed via Kaplan-Meier, evaluated time to achieving SALT≤20 without regression to SALT>30 within 6 months. Results In total, 741 patients were included (median age at index: 27 years; 52.6% female). Mean (SD) SALT score at index was 63.5 (15.6); 80.2% had patchy AA and 19.8% had alopecia totalis or universalis. Topical corticosteroids were the most common treatment post-index, with 55.6% receiving ≥1 course with median cumulative exposure of 4 months. Systemic and intralesional corticosteroids (44.1% and 22.5%, respectively), systemic immunosuppressants (22.0%), and oral (17.3%) or topical (19.4%) minoxidil were also common. Mean (SD) absolute SALT reduction at 12 months post-index was -44.6% (37.3%). However, at 12 months, few patients (10.6%) achieved SALT≤20 that was sustained for ≥6 months. Conclusions Although patients in this study experienced substantial absolute SALT score reductions, few achieved and sustained SALT≤20. These findings highlight potential suboptimal effectiveness of the varied treatments applied in this population.