Predictors of Response to Topical Ruxolitinib in Non-segmental Vitiligo: A Narrative Review.

Topical ruxolitinib 1.5% cream is the first approved therapy for repigmentation in non-segmental vitiligo. However, treatment response varies, and reliable predictors of efficacy remain undefined. This narrative review examined clinical trials and observational studies investigating factors associated with response to ruxolitinib cream. A comprehensive search of MEDLINE, Cochrane CENTRAL and ClinicalTrials.gov (through June 2025) identified 14 eligible studies. Anatomical site was the most consistent predictor, with facial lesions showing the highest repigmentation rates and acral areas demonstrating poor response. Early clinical improvement was associated with better long-term outcomes. Long-term data indicated that repigmentation can persist after treatment discontinuation in a substantial proportion of patients. Demographic and disease-related variables, including age, sex, disease duration and phototype, showed mixed results across studies. Adjunctive narrowband UVB improved repigmentation in initial non-responders but provided limited benefit in early responders. Exploratory biomarker data suggested that Th2 cytokine profiles and reductions in CXCL10 levels may be linked to response, although these findings remain unvalidated. Overall, anatomical location and early clinical response appear to be the most reliable indicators of ruxolitinib efficacy. Further studies with standardized endpoints and predictive modelling are needed to guide individualized treatment strategies in vitiligo.