Recruiting
Phase 2

ACT-777991

Sponsor:

Idorsia Pharmaceuticals Ltd.

Code:

NCT07667569

Conditions

Non-Segmental Vitiligo

Eligibility Criteria

Sex: All

Age: 18 - 65

Healthy Volunteers: Not accepted

Interventions

ACT-777991

Placebo

Study Details

Brief summary:

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.

Conditions

Non-Segmental Vitiligo

Study ID

NCT07667569

Start date

Oct 6, 2026

Status verified date

Oct, 2026

Completion date

Jul 31, 2027

Anticipated

Primary completion date

Jun 28, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 65

Healthy Volunteers: Not accepted

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.

Applicable only to EU: In addition to the above, participants must not have discontinued, reduced, or modified a vitiligo treatment/ procedure for the purpose of meeting trial eligibility criteria or a wash out requirement.

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 m\^2, defined by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine equation, at Screening.

Study Design

Enrollment

30 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: ACT-777991

Participants will receive ACT-777991 tablets orally for 24 weeks.

placebo comparator: Placebo

Participants will receive placebo tablets orally for 24 weeks.

Interventions

ACT-777991

ACT-777991 tablets

Placebo

ACT-777991-matching placebo tablets

Primary outcome measure

  • 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 ]

Central Contacts and Locations

Central contacts

Clinical Trial Information USA

+1 856 661 37 21idorsiaclinicaltrials@idorsia.com

Clinical Trial Information Europe

+41 58 844 1977idorsiaclinicaltrials@idorsia.com

Locations

Vitiligo & Pigmentation Institute of Southern California

Recruiting

Los Angeles, California, United States, 90036

More Information

Sponsor

Idorsia Pharmaceuticals Ltd.

Last update posted

Nov 2, 2026

Last verified

Oct, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-11-03. This information was provided to ClinicalTrials.gov by Idorsia Pharmaceuticals Ltd. on 2026-11-02. Recruitment status is synced daily from ClinicalTrials.gov and may not reflect the sponsor's current status. Confirm during your call.