Phase 2b Analysis Shows Consistent Vitiligo Repigmentation With Ritlecitinib

Oral ritlecitinib demonstrated clinically meaningful facial repigmentation across a wide range of demographic and clinical subgroups in patients with active nonsegmental vitiligo, according to a newly published post hoc analysis of a phase 2b trial.¹ The findings suggest that treatment response was generally consistent across patient characteristics, with early numerical differences between subgroups diminishing over longer-term treatment.

The analysis, published in JEADV Clinical Practice, evaluated outcomes from a randomized phase 2b study of ritlecitinib, a selective JAK3 and TEC family kinase inhibitor currently approved for alopecia areata and under phase 3 investigation for vitiligo.² Investigators examined whether baseline demographic and disease-related factors influenced treatment efficacy over 48 weeks.

Study design and population

The original phase 2b trial enrolled adults aged 18 to 65 years with active nonsegmental vitiligo involving at least 0.25% facial body surface area. Active disease was defined by recent lesion progression or characteristic clinical features such as confetti or trichrome lesions. During the initial 24-week dose-ranging period, patients received ritlecitinib 50 mg once daily, with or without a short loading dose. A subset of patients continued into a 24-week extension period, during which they received ritlecitinib 50 mg daily following a 4-week 200 mg loading dose.

The post hoc analysis included 184 patients from the dose-ranging period and 90 patients from the extension phase. Efficacy was assessed using the centrally read Facial Vitiligo Area Scoring Index, with the primary outcome defined as achievement of at least 75% improvement from baseline (F-VASI75) at weeks 24 and 48.

Patients were stratified by multiple baseline variables, including age, sex, race, body mass index (BMI), Fitzpatrick skin type, disease duration, presence of leukotrichia, facial disease extent, prior treatment exposure, and comorbidities.

Overall efficacy and subgroup findings

Across the overall study population, 8.7% of patients achieved F-VASI75 at week 24. By week 48, following continued treatment, the response rate increased to 26.7%, indicating greater repigmentation with longer therapy duration.

Ritlecitinib demonstrated efficacy across all analyzed subgroups. While numerical differences in response rates were observed at week 24, none reached statistical significance, and most differences narrowed or resolved by week 48.

At week 24, researchers found men showed a higher numerical response than women, and patients with Fitzpatrick skin types III to VI appeared to respond more favorably than those with types I or II. Similarly, higher early response rates were observed in patients without leukotrichia, those with greater baseline facial involvement, and treatment-naïve individuals. However, by week 48, response rates were largely comparable across these groups.

Some numerical differences persisted at the end of the extension period. Patients with BMI ≤30 kg/m² demonstrated higher response rates than those with obesity, and patients without leukotrichia or systemic comorbidities showed numerically greater repigmentation. Investigators noted that these findings should be interpreted cautiously, as subgroup sizes were small and confidence intervals overlapped.

Clinical context

The results align with prior subgroup analyses of ritlecitinib showing efficacy across Fitzpatrick skin types and in both active and stable lesions. They also mirror findings from studies of other JAK inhibitors used in vitiligo, including topical ruxolitinib and oral povorcitinib, which have demonstrated repigmentation across diverse patient populations.

Notably, some trends observed with ritlecitinib differ from those reported with other agents. For example, younger age and women have been associated with higher response rates in some ruxolitinib and povorcitinib analyses, whereas early responses in this study numerically favored male patients, with age-related differences not observed. These variations underscore the complexity of vitiligo treatment response and the need for cautious cross-trial comparisons.

Limitations and implications

As a post hoc analysis, the study was not powered to detect statistically significant differences between subgroups. The extension phase included fewer patients and lacked a placebo control, limiting definitive conclusions regarding long-term comparative efficacy. Additionally, imbalances in subgroup sizes reduced the robustness of certain observations.

Despite these limitations, the findings suggest that ritlecitinib’s repigmentation effects are broadly consistent across common clinical and demographic characteristics. For clinicians, this may provide reassurance that factors such as skin type, prior treatment history, or disease duration are unlikely to preclude response, particularly with longer-term therapy.

Further data from ongoing phase 3 trials will be needed to confirm these findings and better define the patient populations most likely to benefit from ritlecitinib in routine clinical practice.

References

1. Pandya A, Hamzavi I, Ghosh P, Ezzedine K, Harris J, Adiri R, Chen S, Peeva E, Yamaguchi Y. Efficacy of ritlecitinib for vitiligo treatment stratified by baseline demographic and clinical characteristics: post hoc analysis of a phase 2b study. JEADV Clin Prac. 2026. doi:10.1002/jvc2.70193.
2. Tziotzios C, Sinclair R, Lesiak A, et al. Long-term safety and efficacy of ritlecitinib in adults and adolescents with alopecia areata and at least 25% scalp hair loss: Results from the ALLEGRO-LT phase 3, open-label study. J Eur Acad Dermatol Venereol. 2025;39(6):1152-1162. doi:10.1111/jdv.20526