Longer Use of Topical JAK Inhibitors Shows Better Vitiligo Results in Study
Why this matters
If you or someone you love has vitiligo, you may be wondering how long a new treatment should be tried before deciding if it’s helping. A recent real-world study looked at people using creams that block Janus kinase, often called JAK inhibitors. The study suggests that staying on these topical treatments longer makes it more likely that some repigmentation will be seen. But it also raises questions about access and who was included in the research.
What the study looked at
The research reviewed medical records from an academic dermatology clinic in Southern California. It included 120 people with vitiligo who had been treated with topical JAK inhibitor creams between April 2018 and April 2024. To be included, people needed at least two dermatology visits, a recorded Vitiligo Area Scoring Index score, insurance information, and current or past use of a topical JAK inhibitor (Source: Rizwi H et al., JID Innovations).
Who was in the group?
The group was racially and ethnically diverse: about 34% Asian, 17% Hispanic, and 49% White. The average age was 42. On average, people had used the topical JAK treatment for about 9.7 months. Doctors classified vitiligo this way:
- Generalized: 40%
- Localized: 37.5%
- Acrofacial (hands, face, or fingers): 18.3%
- Segmental: 4.2%
How the study measured improvement
Investigators used the Vitiligo Area Scoring Index (VASI), a common way to track how much lighter or depigmented the skin is. For this study, any drop in a person’s VASI score from their first visit to the most recent visit counted as “improvement.”
Main finding: longer treatment was linked to better odds of improvement
People who showed improvement had been on topical JAK inhibitors longer. On average, those who improved had used the treatment for about 13 months, while those without improvement had used it for about 8 months. Statistically, each extra month of treatment was associated with an 11% increase in the odds of seeing any VASI improvement (adjusted odds ratio 1.11, 95% CI 1.04–1.20). The link stayed significant after accounting for sex, ethnicity, age, skin type, vitiligo type, and whether they also used narrowband UVB light therapy (Source: Rizwi H et al., JID Innovations).
In plain language, this suggests repigmentation can be slow and that giving these topical treatments time may be important before deciding whether they are working.
What about ethnicity and response?
The study found that Hispanic patients were more likely to show any VASI improvement: about 50% of Hispanic patients improved versus 27% of non-Hispanic patients on initial analysis. After statistical adjustment, non-Hispanic patients had lower odds of improvement compared to Hispanic patients (adjusted odds ratio 0.307). But the researchers urged caution.
Why be cautious? The Hispanic group had more people with localized vitiligo, which can be easier to treat. The total number of participants was fairly small, and some important subgroups (for example, Black patients) were underrepresented. That means these ethnicity findings might be influenced by other factors the study couldn’t fully account for. The authors said larger studies are needed to understand whether ethnicity itself plays a role, or if other differences explain the pattern (Source: Rizwi H et al., JID Innovations).
Who got denied treatment more often?
The researchers also looked at prescription approvals. They found that patients with public insurance (for example, government-funded plans) made up 60% of prescription denials, while privately insured patients made up 40% of denials. This difference was statistically significant. The authors suggested that insurance barriers could add to existing gaps in access to vitiligo treatments (Source: Rizwi H et al., JID Innovations).
Limitations to keep in mind
This was a single-center, retrospective review of medical records, which means it looked back at what already happened instead of assigning treatments in a controlled way. The study had a modest number of people and limited representation of some racial and skin-type groups. Also, “improvement” was any drop in VASI score, so the study did not measure how much the skin repigmented or whether the change was clinically meaningful to patients. Because of these limits, results should be seen as an early look at real-world patterns, not a final answer.
What the researchers recommend next
The authors called for larger, multi-center studies that include more people from underrepresented groups. They also want standardized ways to record VASI scores, objective measures of pigment change, and data about social factors that affect health and access to care. These steps would help researchers understand who benefits most from topical JAK inhibitors and whether barriers to treatment are widening disparities.
Tracking changes in your skin
If you’re trying a new treatment for vitiligo and want to track progress, taking regular photos under consistent lighting and noting dates can help you and your dermatologist see gradual changes over time. This kind of documentation can be useful during follow-up visits.
When to see a doctor
If your vitiligo causes distress, spreads quickly, changes in a way that worries you, becomes painful, bleeds, or shows signs of infection, make an appointment with a dermatologist. Also talk with your dermatologist if you’re starting a topical JAK inhibitor so you understand how long to try it, what to expect, and what side effects to watch for.
Short disclaimer
This article summarizes a single retrospective study and does not offer medical advice. Treatment decisions should be made with your dermatologist or healthcare provider.
Sources
- Rizwi H, Nguyen BT, Chahine A, Dahdoul T, Shiu J. Demographic factors associated with response to topical Jak inhibitors in a diverse vitiligo cohort. JID Innovations. DOI:10.1016/j.xjidi.2026.100520. https://pubmed.ncbi.nlm.nih.gov/42733611/ (Source: study report)
- Rosmarin D, Passeron T, Pandya AG, et al. Two phase 3, randomized, controlled trials of ruxolitinib cream for vitiligo. 2022;387:1445-1455. https://pubmed.ncbi.nlm.nih.gov/36260792/ (Source: published clinical trials)