A Clinical Study of MK-6194 for the Treatment of Vitiligo (MK-6194-007)

A Phase 2a, Multicenter, Randomized, Double-blind, Placebo-controlled Study to Evaluate the Efficacy and Safety of MK-6194 in Adult Participants With Non-Segmental Vitiligo

Researchers are looking for a new way to treat people with non-segmental vitiligo (NSV). The goal of this study is to learn about the safety of MK-6194 and how well people tolerate it. Researchers also want to learn if people who take MK-6194 have more of a decrease in the amount of vitiligo on their face compared to people who take placebo.

Study Overview

• Status: Terminated
• Conditions: Non-segmental Vitiligo
• Intervention / Treatment: Biological: MK-6194; Drug: Placebo

Detailed Description

This study will consist of two periods. During the Double-Blind Treatment Period, participants will be randomized to one of three treatment arms to receive MK-6194 at one of two doses or placebo and will be evaluated for safety and efficacy. Participants who complete this period may enter the Blinded Extension Period, during which MK-6194 treatment will continue or placebo recipients will be re-randomized to MK-6194 at one of two doses.

• Study Type: Interventional
• Enrollment (Actual): 169
• Phase: Phase 2

Contacts and Locations

Study Locations

• Argentina
  • Buenos Aires, Argentina, C1118AAT
    • Hospital Aleman-Dermatologia ( Site 0209)
  • Buenos Aires
    • Ciudad Autonoma de Buenos Aires, Buenos Aires, Argentina, C1425DKG
      • Psoriahue ( Site 0205)
  • Buenos Aires F.D.
    • Buenos Aires, Buenos Aires F.D., Argentina, C1023AAB
      • Stat Research S.A. ( Site 0204)
    • Buenos Aires, Buenos Aires F.D., Argentina, C1027AAP
      • Centro de Investigaciones Metabólicas (CINME)-Dermatology ( Site 0203)
  • Córdoba Province
    • Córdoba, Córdoba Province, Argentina, X5000EDC
      • Instituto Medico Strusberg ( Site 0208)
• Australia
  • Australian Capital Territory
    • Phillip, Australian Capital Territory, Australia, 2606
      • Paratus Clinical Research Woden ( Site 1703)
  • New South Wales
    • Westmead, New South Wales, Australia, 2145
      • Westmead Hospital-Dermatology ( Site 1701)
  • Victoria
    • Carlton, Victoria, Australia, 3053
      • Skin Health Institute Inc.-Trials ( Site 1702)
    • Melbourne, Victoria, Australia, 3002
      • Sinclair Dermatology ( Site 1704)
• Belgium
  • Oost-Vlaanderen
    • Ghent, Oost-Vlaanderen, Belgium, 9000
      • UZ Gent ( Site 0604)
  • Vlaams-Brabant
    • Leuven, Vlaams-Brabant, Belgium, 3000
      • UZ Leuven ( Site 0601)
• Canada
  • British Columbia
    • Surrey, British Columbia, Canada, V3V 0C6
      • Enverus Medical Research ( Site 0006)
  • Quebec
    • Québec, Quebec, Canada, G1V 4T3
      • Diex Recherche Quebec Inc. ( Site 0008)
    • Québec, Quebec, Canada, G1V 4X7
      • Centre de Recherche Dermatologique du Quebec metropolitain ( Site 0002)
    • Sherbrooke, Quebec, Canada, J1L 0H8
      • Diex Recherche sherbrooke Inc. ( Site 0007)
• Chile
  • Los Lagos Region
    • Osorno, Los Lagos Region, Chile, 5310644
      • Dermisur ( Site 0305)
  • Los Ríos Region
    • Valdivia, Los Ríos Region, Chile, 5110683
      • Clinical Research Chile SpA ( Site 0304)
  • Region M. de Santiago
    • Santiago, Region M. de Santiago, Chile, 7640881
      • Clinica Dermacross ( Site 0301)
    • Santiago, Region M. de Santiago, Chile, 8420383
      • Centro Internacional de Estudios Clinicos (CIEC) ( Site 0302)
    • Santiago, Region M. de Santiago, Chile, 8330034
      • Pontificia Universidad Catolica de Chile-CICUC ( Site 0308)
• Colombia
  • Antioquia
    • Envigado, Antioquia, Colombia, 055422
      • CliniSalud ( Site 0401)
    • Medellín, Antioquia, Colombia, 50016
      • IPS SURA San Diego ( Site 0408)
  • Atlántico
    • Barranquilla, Atlántico, Colombia, 080002
      • Centro Integral de Reumatología del Caribe ( Site 0405)
  • Cundinamarca
    • Zipaquirá, Cundinamarca, Colombia, 250252
      • Healthy Medical Center S.A.S ( Site 0403)
  • Valle del Cauca Department
    • Cali, Valle del Cauca Department, Colombia, 760032
      • Fundación Valle del Lili ( Site 0412)
• France
  • Alpes-Maritimes
    • Nice, Alpes-Maritimes, France, 06202
      • Centre Hospitalier Universitaire de Nice - Hôpital l'Archet ( Site 0803)
  • Aquitaine
    • Bordeaux, Aquitaine, France, 33075
      • CHU de Bordeaux Hop St ANDRE ( Site 0804)
  • Auvergne-Rhône-Alpes
    • Lyon, Auvergne-Rhône-Alpes, France, 69003
      • Hôpital Edouard Herriot ( Site 0802)
  • Val-de-Marne
    • Créteil, Val-de-Marne, France, 94000
      • HENRI MONDOR HOSPITAL ( Site 0801)
• Germany
  • Berlin, Germany, 10117
    • Charité Universitaetsmedizin Berlin - Campus Mitte ( Site 0901)
  • Bavaria
    • Erlangen, Bavaria, Germany, 91054
      • Universitaetsklinikum Erlangen-Hautklinik Studienambulanz ( Site 0905)
  • North Rhine-Westphalia
    • Münster, North Rhine-Westphalia, Germany, 48149
      • Universitätsklinikum Münster-Hautklinik ( Site 0904)
• Israel
  • Haifa, Israel, 3109601
    • Rambam Health Care Campus-Dermatology ( Site 1002)
  • Ramat Gan, Israel, 5265601
    • Sheba Medical Center-Dermatology ( Site 1001)
• Japan
  • Aichi-ken
    • Nagoya, Aichi-ken, Japan, 467-8602
      • Nagoya City University Hospital-Dermatology ( Site 2002)
  • Osaka
    • Suita, Osaka, Japan, 565-0871
      • Osaka University Hospital ( Site 2004)
  • Tokyo
    • Shinjuku-ku, Tokyo, Japan, 160-0023
      • Tokyo Medical University Hospital ( Site 2001)
• Mexico
  • Aguascalientes, Mexico, 20129
    • Centro de Atención e Investigación Clínica ( Site 0507)
  • Mexico City
    • Cuauhtémoc, Ciudad de México, Mexico City, Mexico, 06100
      • Cryptex Investigación Clínica S.A. de C.V. ( Site 0515)
  • Nuevo León
    • Monterrey, Nuevo León, Mexico, 64460
      • Unidad biomedica avanzada monterrey-Clinical Trials ( Site 0504)
• Netherlands
  • North Holland
    • Amsterdam, North Holland, Netherlands, 1105 AZ
      • Amsterdam UMC, locatie AMC-Dermatology ( Site 1101)
• South Korea
  • Incheon, South Korea, 22332
    • Inha University Hospital ( Site 1992)
  • Seoul, South Korea, 03080
    • Seoul National University Hospital-Dermatology ( Site 1991)
  • Seoul, South Korea, 03722
    • Severance Hospital, Yonsei University Health System-Department of Dermatology ( Site 1993)
• Spain
  • Andalusia
    • Cadiz, Andalusia, Spain, 11009
      • Hospital Universitario Puerta del Mar ( Site 1302)
  • Barcelona
    • L'Hospitalet de Llobregat, Barcelona, Spain, 08907
      • Hospital Universitari de Bellvitge-Dermatology ( Site 1307)
  • Madrid, Comunidad de
    • Madrid, Madrid, Comunidad de, Spain, 28027
      • Clinica Universidad de Navarra ( Site 1305)
• Switzerland
  • Canton of St. Gallen
    • Sankt Gallen, Canton of St. Gallen, Switzerland, 9007
      • Cantonal Hospital St.Gallen ( Site 1402)
  • Canton of Zurich
    • Zurich, Canton of Zurich, Switzerland, 8091
      • UniversitätsSpital Zürich ( Site 1401)
• Turkey (Türkiye)
  • Ankara, Turkey (Türkiye), 06800
    • Ankara Bilkent Şehir Hastanesi-Dermatology ( Site 1502)
  • Kayseri, Turkey (Türkiye), 38039
    • Erciyes Universitesi Tıp Fakultesi Hastaneleri-Dermatology and Venereology ( Site 1506)
  • Ankara
    • Altindağ, Ankara, Turkey (Türkiye), 06230
      • Hacettepe Universite Hastaneleri-Dermatology ( Site 1501)
• United Kingdom
  • Wolverhampton, United Kingdom, WV10 0QP
    • New Cross Hospital ( Site 1601)
  • England
    • London, England, United Kingdom, E1 1BB
      • Royal London Hospital-Dermatology Research Unit ( Site 1605)
  • Warwickshire
    • Birmingham, Warwickshire, United Kingdom, B15 2TH
      • Queen Elizabeth Hospital Birmingham ( Site 1603)
• United States
  • Alabama
    • Birmingham, Alabama, United States, 35244
      • Cahaba Dermatology & Skin Health Center ( Site 0127)
  • Arkansas
    • Hot Springs, Arkansas, United States, 71913
      • Burke Pharmaceutical Research ( Site 0124)
  • California
    • Los Angeles, California, United States, 90036
      • The Vitiligo & Pigmentation Institute of Southern California ( Site 0115)
  • Indiana
    • Indianapolis, Indiana, United States, 46202
      • Indiana University Health University Hospital-Indiana University School of Medicine, Department of (
    • Indianapolis, Indiana, United States, 46250
      • Dawes Fretzin Clinical Research Group, LLC ( Site 0106)
  • Massachusetts
    • Brighton, Massachusetts, United States, 02135
      • Metro Boston Clinical Partners ( Site 0110)
  • Michigan
    • Canton, Michigan, United States, 48187
      • Hamzavi Dermatology - Canton ( Site 0101)
  • Ohio
    • Columbus, Ohio, United States, 43215
      • Remington Davis Clinical Research-Outpatient ( Site 0104)
  • South Carolina
    • Charleston, South Carolina, United States, 29425
      • Medical University of South Carolina-Dermatology Research ( Site 0114)
  • Tennessee
    • Murfreesboro, Tennessee, United States, 37130
      • International Clinical Research - Tennessee LLC ( Site 0120)
  • Texas
    • San Antonio, Texas, United States, 78213
      • Progressive Clinical Research ( Site 0108)
  • Virginia
    • Norfolk, Virginia, United States, 23502
      • Virginia Clinical Research, Inc. ( Site 0109)
  • Washington
    • Spokane, Washington, United States, 99202
      • Dermatology Specialists of Spokane ( Site 0126)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Has a clinical diagnosis of non-segmental vitiligo
• Has non-segmental vitiligo with disease duration of at least 6 months
• Has depigmentation contributing to Facial Vitiligo Area Scoring Index (F-VASI) ≥ 0.3 at screening and baseline
• Has depigmented facial body surface area (BSA) ≥0.3% at screening and baseline
• Has Total Vitiligo Area Scoring Index (T-VASI) ≥4 at screening and baseline
• Has total body vitiligo area ≥4% at screening and baseline excluding hands and feet involvement

Exclusion Criteria:

• Has segmental vitiligo
• Has ≥50% leukotrichia on face or body
• Has any other dermatological diseases that would interfere with vitiligo assessments
• Has history of or current inflammatory condition other than vitiligo that, in the opinion of the investigator, could interfere with the evaluation of vitiligo
• Has a known systemic hypersensitivity to interleukin 2 (IL-2), or modified IL-2 including MK-6194, or its inactive ingredients
• Has an active or clinically significant infection requiring hospitalization or treatment with IV anti-infectives within 4 weeks prior to Randomization, or oral/intramuscular anti-infective therapy within 2 weeks prior to Randomization
• Has symptomatic heart failure (New York Heart Association class III or IV) or myocardial infarction or unstable angina pectoris within 6 months prior to Screening
• Has a severe chronic pulmonary disease requiring oxygen therapy
• Has a transplanted organ, which requires continued immunosuppression
• Has a history of any malignancy, except for successfully treated non-melanoma skin cancer or localized carcinoma in situ of the cervix
• Has evidence of active tuberculosis (TB), latent TB, or inadequately treated TB
• Has confirmed or suspected COVID-19 infection
• Has history of drug or alcohol abuse within 6 months prior to Screening
• Has had major surgery within 3 months prior to Screening OR has a major surgery planned during the study
• Has had an inadequate response (as evaluated by a dermatologist or local physician specialist equivalent) to previous treatment with a Janus kinase inhibitor (JAKi) after an appropriate treatment duration (eg, ≥12 weeks)
• Has received prohibited medications within protocol-specified timeframes prior to Randomization
• Has participated in another investigational clinical study within 4 weeks prior to Randomization
• Has donated or lost ≥1 unit of blood (approximately 500 mL) within 4 weeks prior to the Screening Visit
• Has received cosmetic or other procedures that could interfere with evaluation of vitiligo during the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

7

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: MK-6194 3 mg Q2W; Participants will receive subcutaneous (SC) MK-6194 3 mg every two weeks (Q2W).	Biological: MK-6194; MK-6194 administered subcutaneously (SC)
Experimental: MK-6194 3 mg Q4W; Participants will receive SC MK-6194 3 mg every four weeks (Q4W).	Biological: MK-6194; MK-6194 administered subcutaneously (SC)
Placebo Comparator: Placebo; Participants will receive SC Placebo Q2W.	Drug: Placebo; Placebo comparator to MK-6194 administered SC
Experimental: MK-6194 3 mg Q2W (double-blind) / MK-6194 3 mg Q2W (extension); After completing 24 weeks of treatment with SC MK-6194 administered 3 mg Q2W in the Double-Blind Treatment Period, participants will continue to receive SC MK-6194 3 mg Q2W in the Blinded Extension Period.	Biological: MK-6194; MK-6194 administered subcutaneously (SC)
Experimental: MK-6194 3 mg Q4W (double-blind) / MK-6194 3 mg Q4W (extension); After completing 24 weeks of treatment with SC MK-6194 administered 3 mg Q4W in the Double-Blind Treatment Period, participants will continue to receive SC MK-6194 3 mg Q4W in the Blinded Extension Period.	Biological: MK-6194; MK-6194 administered subcutaneously (SC)
Experimental: Placebo (double-blind)/ MK-6194 3 mg Q2W (extension); After completing 24 weeks of treatment with SC Placebo administered Q2W in the Double-Blind Treatment Period, participants will be re-randomized to receive SC MK-6194 3 mg Q2W in the Blinded Extension Period.	Biological: MK-6194; MK-6194 administered subcutaneously (SC)
Experimental: Placebo (double-blind)/ MK-6194 3 mg Q4W (extension); After completing 24 weeks of treatment with SC Placebo administered Q2W in the Double-Blind Treatment Period, participants will be re-randomized to receive SC MK-6194 3 mg Q4W in the Blinded Extension Period.	Biological: MK-6194; MK-6194 administered subcutaneously (SC)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent Change From Baseline in Facial Vitiligo Area Scoring Index (F-VASI) at Week 24	VASI is a validated scoring method that measures the extent and severity of vitiligo depigmentation. The F-VASI measures vitiligo involvement of the facial area. For facial lesions, size is estimated using fingertip units (FTU), fingers, or thumbs: 1 FTU is approximately 0.03% body surface area (BSA), while a finger or thumb is approximately 0.1% BSA. Depigmentation at each site is graded to the nearest percentage: 0%, 10%, 25%, 50%, 75%, 90%, or 100%. F-VASI is calculated by multiplying the area (in FTUs) by the depigmentation percentage for each facial site and summing the values. Scores range from 0 to approximately 3.5, with higher scores indicating greater vitiligo involvement of the facial area (more severe depigmentation). Percent change from baseline calculated as post-baseline value minus baseline value, divided by baseline value and multiplied by 100%. Longitudinal data analysis (LDA) model-based least squares mean (LSM) percent change from baseline to Week 24 was reported.	Baseline and Week 24
Number of Participants Who Experienced an Adverse Event (AE)	An AE is defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention whether or not considered related to the study intervention. The number of participants who experienced an AE is reported.	Up to approximately 28 weeks
Number of Participants Who Discontinued Study Treatment Due to an AE	An AE is defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention whether or not considered related to the study intervention. The number of participants who discontinued study treatment due to an AE is reported here.	Up to approximately 24 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent Change From Baseline in Total Vitiligo Area Scoring Index (T-VASI) at Week 24	T-VASI is a validated scoring method that measures the extent and severity of vitiligo across the entire body. The body is divided into six regions: head/neck, hands, upper extremities, trunk, lower extremities, and feet. One hand unit (palm and fingers together) represents 1% of BSA. Depigmentation for each region is graded to the nearest percentage: 0%, 10%, 25%, 50%, 75%, 90%, or 100%. For regions with multiple lesions, percentages are averaged. The T-VASI score is calculated by multiplying the area (in hand units) by the depigmentation percentage for each region and summing all regions. Scores range from 0 to 100, with 0 indicating no vitiligo and 100 indicating complete body involvement. Percent change from baseline calculated as post-baseline value minus baseline value, divided by baseline value and multiplied by 100%. LDA model-based LSM percent change from baseline to Week 24 was reported.	Baseline and Week 24

Collaborators and Investigators

• Sponsor: Merck Sharp & Dohme LLC
• Investigators: Study Director: Medical Director, Merck Sharp & Dohme LLC

Publications and helpful links

Helpful Links

• Merck Clinical Trials Information
• Plain Language Summary

Study record dates

Study Major Dates

• Study Start (Actual): November 27, 2023
• Primary Completion (Actual): March 20, 2025
• Study Completion (Actual): July 30, 2025

Study Registration Dates

• First Submitted: October 27, 2023
• First Submitted That Met QC Criteria: October 27, 2023
• First Posted (Actual): November 2, 2023

Study Record Updates

• Last Update Posted (Actual): March 17, 2026
• Last Update Submitted That Met QC Criteria: February 23, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Skin Diseases; Hypopigmentation; Pigmentation Disorders; Vitiligo
• Other Study ID Numbers: 6194-007; 2023-503502-37-00 (Registry Identifier: EU CT); U1111-1287-4329 (Registry Identifier: UTN); MK-6194-007 (Other Identifier: MSD); jRCT2031230622 (Registry Identifier: jRCT)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No