A Study to Learn How Safe ACT-777991 is and How Well it Works in Adults With Non-segmental Vitiligo
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: ACT-777991, Placebo.
- Who it may be relevant to
- Registry conditions: Non-Segmental Vitiligo. Basic parameters: 18 years — 65 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Center list to be confirmed — check the primary protocol.
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
Unsure about the terms? Read our patient guide →
Official title
A Phase 2a, Proof of Concept, Multicenter, Double Blind, Randomized, Placebo Controlled, Parallel Group Trial to Assess the Efficacy and Safety of ACT-777991 in Adults With Non-segmental Vitiligo
Overview
The purpose of this clinical trial is to learn how well ACT-777991 works, how safe it is and how well it is tolerated by adults with non-segmental vitiligo. The main question this clinical trial aims to answer is: • Can ACT-777991 help return color to the skin of the face of adults with non-segmental vitiligo? Researchers will compare ACT-777991 to placebo (a look-alike inactive treatment that contains no medicine) to see if ACT-777991 works to treat non-segmental vitiligo. Trial participants will: * Take the trial intervention (either ACT-777991 or placebo) daily for 24 weeks. * Visit the clinic 7 times for check-up and tests.
Detailed description
The trial includes three trial periods:
Following a Screening period, during which it will be checked if participants are eligible to take part, eligible participants will be randomized in a 2:1 ratio to receive either ACT-777991 or placebo for 24 weeks (Trial intervention period). On completion of treatment, participants will be followed for 30 (+7) days (Follow-up period).
Trial participation will end with a Follow-up visit (Participant Last Visit) at the end of the Follow-up period.
The maximum trial duration for an individual participant is approximately 33 weeks including a screening period of up to 28 days, a treatment period of 24 weeks, and a follow-up period of up to 37 days.
Interventions
- Drug ACT-777991
ACT-777991 tablets - Drug Placebo
ACT-777991-matching placebo tablets
Primary outcome measures
- Main primary outcome measure: Percentage change from baseline in Facial Vitiligo Area Scoring Index (F-VASI) based on Blinded Independent Central Reading (BICR) at Week 24 [Time frame: Baseline; Week 24]
- Supplementary primary outcome measure: Percentage change from baseline in F-VASI based on investigator assessment at Week 24 [Time frame: Baseline; Week 24]
- Supplementary primary outcome measure: Percentage change from baseline in F-VASI at Week 4, 8 and 16 [Time frame: Baseline; Week 4, Week 8; Week 16]
- Supplementary primary outcome measure: Achievement of F-VASI50 at Week 4, 8, 16 and 24 [Time frame: Baseline; Week 4; Week 8; Week 16; Week 24]
- Supplementary primary outcome measure: Achievement of F-VASI75 at Week 4, 8, 16 and 24 [Time frame: Baseline; Week 4; Week 8; Week 16; Week 24]
- Supplementary primary outcome measure: Achievement of F-VASI90 at Week 4, 8, 16 and 24 [Time frame: Baseline; Week 4; Week 8; Week 16; Week 24]
Secondary outcome measures (12)
- Percentage change from baseline in Total Body Vitiligo Area Scoring Index (T-VASI) at Week 4, 8, 16 and 24 [Time frame: Baseline; Week 24]
- Achievement of T-VASI50 at Week 4, 8, 16 and 24 [Time frame: Baseline; Week 4; Week 8; Week 16; Week 24]
- Adverse events (AEs) leading to premature discontinuation of trial intervention [Time frame: From start of trial intervention to last dose of trial intervention, assessed up to Week 24]
- Treatment-emergent AEs and serious AEs (SAEs) [Time frame: From start of trial intervention up to 37 days after last dose of trial intervention (Follow-up visit)]
- Treatment-emergent AEs of special interest (AESI) [Time frame: From start of trial intervention up to 37 days after last dose of trial intervention (Follow-up visit)]
- Change from baseline in vital signs: systolic and diastolic blood pressure [Time frame: Baseline to all pre-defined time points, up to 37 days after last dose of trial intervention (Follow-up visit)]
- Change from baseline in vital signs: pulse rate [Time frame: Baseline to all pre-defined time points, up to 37 days after last dose of trial intervention (Follow-up visit)]
- Change from baseline in hematology variables [Time frame: Baseline to all pre-defined time points, up to 37 days after last dose of trial intervention (Follow-up visit)]
- Change from baseline in blood chemistry variables [Time frame: Baseline to all pre-defined time points, up to 37 days after last dose of trial intervention (Follow-up visit)]
- Change from baseline in ECG parameters: PR interval, QRS duration, QTcF Value [Time frame: Baseline to all pre-defined time points, up to 37 days after last dose of trial intervention (Follow-up visit)]
- Change from baseline in ECG parameters: Heart rate [Time frame: Baseline to all pre-defined time points, up to 37 days after last dose of trial intervention (Follow-up visit)]
- Number of Participants with treatment-emergent marked abnormalities in vital signs: systolic and diastolic blood pressure, pulse rate [Time frame: From start of trial intervention up to 37 days after last dose of trial intervention (Follow-up visit)]
Eligibility criteria
Inclusion criteria
- Clinical diagnosis of either active or stable non segmental vitiligo for at least 3 months prior to Screening and meet all the following criteria:
- F-VASI score ≥ 0.3 based on BICR at Screening.
- T-VASI score ≥ 5 based on investigator assessment at Screening and Randomization.
- Total body surface area (BSA) involvement, including the face, ≤ 50% based on investigator assessment at Screening and Randomization.
- Participants must agree not to use therapeutic agents and procedures to treat vitiligo from Screening until Participant Last Visit.
Exclusion criteria
- Clinical diagnosis of other forms of vitiligo (e.g., segmental) or other hypo- or depigmentation disorders (e.g., piebaldism, leukoderma, Vogt-Koyanagi-Harada disease, malignancy-induced hypopigmentation).
- Any autoimmune disease, except adequately treated thyroid disease.
- History of systemic immunotherapy treatment, including JAK inhibitors, for any inflammatory disease in the 12 months prior to Randomization.
- History of topical JAK inhibitors for any inflammatory disease in the 6 weeks prior to Screening.
- Use of laser or light-based treatment (phototherapy), including tanning beds, in the 8 weeks prior to Screening.
- eGFR < 90 mL/min/1.73 m2, defined by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine equation, at Screening.
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Randomized
- Model
- Parallel assignment
- Masking
- Triple blind
- Primary purpose
- Treatment
Study locations
Center list to be confirmed — check the primary protocol.
Identifiers
NCT: NCT07667569 · ID-089B201 · 2025-524865-25-00