25486 Correlation of the Vitiligo Area Scoring Index with patient- and physician-reported measures of clinical improvement in a randomized, double-blind phase 2 study

Abstract

The Vitiligo Area Scoring Index (VASI) is a quantitative clinical tool that estimates the overall area of vitiligo patches (ie, skin depigmentation) and the degree of macular repigmentation within these patches over time. This analysis aimed to evaluate the correlation between facial and total VASI (F-VASI and T-VASI, respectively) with patient- and physician-reported measures of clinical improvement (Patient Global Impression of Change-Vitiligo [PaGIC-V; 7-point scale] and Physician’s Global Vitiligo Assessment [PhGVA]) in a randomized, double-blind phase 2 study of 157 patients with vitiligo. Among stable patients (ie, no change from baseline in PaGIC-V [score of 4]), VASI scores showed excellent test-retest reliability (≥0.95) at Weeks 12 and 24. Significant differences in VASI were detected among PhGVA categories (mild, moderate, severe) at baseline. The VASI detected change in disease status during the treatment period; the changes were significantly different between patients who showed improvement (PaGIC-V, 1-3) or worsening (PaGIC-V, 5-6) and were related to the PaGIC-V (Pearson’s r ∼0.45, P ˂ .0001). To assess interpretability, an anchor-based approach used PaGIC-V (score of 1 or 2) to define clinically meaningful change (CMC) on the VASI at Week 24; mean percentage CMC was 57% for F-VASI and 42% for T-VASI. Results indicated that a higher percentage of patients treated with 1.5% ruxolitinib cream met or exceeded CMC thresholds vs vehicle on F-VASI (39.4% vs 3.1%; P = .0005) and T-VASI (27.3% vs 0%; P = .002). Analyses of efficacy using the F-VASI and T-VASI reflect meaningful and relevant changes in patients with vitiligo.