Post Hoc Subgroup and Body Region Analyses of VASI Outcomes Among Patients with Vitiligo in a Phase 2 Povorcitinib Trial.

INTRODUCTION

A phase 2 trial (NCT04818346) of the oral Janus kinase 1 inhibitor povorcitinib demonstrated substantial total body and facial repigmentation over 52 weeks in adults with extensive nonsegmental vitiligo (NSV). Here, post hoc analyses evaluated povorcitinib efficacy in patients based on demographic and clinical characteristic subgroups, as well as affected body regions.

METHODS

Data were pooled for 103 patients in the extension-evaluable population who received povorcitinib (15, 45, or 75 mg once daily) throughout the 52-week study. Efficacy among subgroups was evaluated using achievement of ≥ 50% reduction from baseline in total Vitiligo Area Scoring Index (T-VASI50) and ≥ 50%/≥ 75% reduction from baseline in facial VASI (F-VASI50/F-VASI75). Efficacy in the affected body regions was evaluated using VASI50 responses. Data were analyzed using descriptive statistics, and missing values were imputed as nonresponders.

RESULTS

At Week 52, 34.0% (35/103) of patients achieved T-VASI50, 61.2% (63/103) achieved F-VASI50, and 45.6% (47/103) achieved F-VASI75. Repigmentation occurred across subgroups regardless of patient age, sex, race, Fitzpatrick skin type, affected body surface area, other autoimmune comorbidities, disease duration, or prior NSV treatment. In addition, VASI50 response rates increased consistently and, in most cases, without plateauing for each body region, ranging from 25.8% for the feet to 57.3% for the head and neck (excluding the face). Decreased rates of disease activity were also evident across body regions.

CONCLUSION

In this exploratory post hoc analysis of adults with extensive NSV, oral povorcitinib produced clinically meaningful repigmentation (as measured by achievement of T-VASI50 and F-VASI75) across patient characteristic subgroups and body regions through 1 year of treatment. Response rates varied by body region, reinforcing the lengthy repigmentation process, especially in nonfacial areas, and highlighting the need to manage patient expectations and encourage adherence to long-term therapy.

TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT04818346.