Randomized, Triple-Blind, Vehicle-Controlled Trial of Topical Dapsone Gel 7.5% in Patients With Acne Vulgaris

NCT07244887 | Completed Phase 4

• 2 other identifiers: SBU-IEAH-AV-DAP7P5-RCT-EC210Medipol-EC-210
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this randomized, triple-blind, vehicle-controlled clinical trial is to evaluate whether topical 7.5% dapsone gel is effective for treating mild-to-moderate acne vulgaris in adults. The main questions are:

• Does dapsone gel improve global acne severity compared with a matched vehicle gel?
• Does dapsone gel improve comedonal and papulopustular acne severity?
• Does dapsone gel reduce erythema and melanin indices measured with a Mexameter, and sebum index measured with a Sebumeter?
• Does treatment with dapsone gel improve patients' acne-related quality of life? Researchers compared once-daily dapsone gel with a matched vehicle gel without the active ingredient. Participants:
• Applied either dapsone gel or vehicle gel once daily for 8 weeks
• Attended clinic visits at baseline, week 4, week 8, and week 12
• Had acne severity assessed using the Global Acne Grading System and Plewig and Kligman comedonal and papulopustular stages
• Had erythema and melanin measured with a Mexameter, and sebum measured with a Sebumeter at predefined facial sites
• Completed an acne quality-of-life questionnaire at baseline and week 8
• Had standardized photographs taken at each visit Treatment was continued for 8 weeks, followed by a 4-week treatment-free follow-up through week 12.

Conditions

Acne Vulgaris

Keywords

Dapsone gel; Topical dapsone 7.5%; Vehicle gel; Mexameter; Erythema; Sebum; Sebumeter; Melanin; Global Acne Grading System (GAGS); Acne Lesion Count; Papulopustular acne; Comedonal acne; Acne Quality of Life Scale (AQOL)

Outcome Measures

Primary Outcomes (1)

• Change in Inflammatory Lesion Count (Papules/Pustules)

  Mean change from baseline in the number of inflammatory facial acne lesions (papules and pustules) per Plewig \& Kligman. Blinded dermatologist, standardized facial mapping. Between-group comparison: topical 7.5% dapsone gel vs vehicle/placebo gel.

  Baseline to Week 8 (with interim assessment at Week 4)

Secondary Outcomes (7)

• Change in Global Acne Grading System (GAGS) Total Score

  Baseline to Week 12, with interim assessments at Week 4 and Week 8

• Change in Plewig and Kligman Comedonal Acne Stage

  Baseline to Week 12, with interim assessments at Week 4 and Week 8

• Change in Erythema Index (Mexameter)

  Baseline to Week 12, with interim assessments at Week 4 and Week 8

• Change in Melanin Index (Mexameter)

  Baseline to Week 12, with interim assessments at Week 4 and Week 8

• Change in Sebum Index (Sebumeter)

  Baseline to Week 12, with interim assessments at Week 4 and Week 8

Study Arms (2)

Dapsone 7.5% Gel

EXPERIMENTAL

Topical dapsone 7.5% gel applied once daily to the entire face for 8 weeks, followed by a 4-week treatment-free follow-up.

Drug: Dapsone 7.5% gel

Vehicle Gel

PLACEBO COMPARATOR

Vehicle gel without dapsone, identical in base, tube, and packaging to the active product; applied once daily to the entire face for 8 weeks, followed by a 4-week treatment-free follow-up.

Drug: Vehicle gel

Interventions

Dapsone 7.5% gel DRUG

Topical dapsone 7.5% gel applied once daily to the entire face for 8 weeks; route: topical. The study product was supplied in an identical-appearing tube to maintain masking. Participants were followed for 4 weeks after treatment discontinuation.

Also known as: topical dapsone 7.5% gel, Vulgarex (country-specific brand)

Dapsone 7.5% Gel

Vehicle gel DRUG

Vehicle gel without dapsone, identical in base, tube, and packaging to the active product; applied once daily to the entire face for 8 weeks; route: topical. Participants were followed for 4 weeks after treatment discontinuation.

Also known as: placebo gel

Vehicle Gel

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Adults aged 18 to 50 years with a clinical diagnosis of mild-to-moderate acne vulgaris.
• No systemic or topical acne treatment within the past 1 month (30 days).
• Able and willing to provide written informed consent.

You may not qualify if:

• Pregnancy or breastfeeding.
• Systemic retinoid or systemic antibiotic use within the past 6 months.
• Active dermatologic or systemic disease that could interfere with study participation or outcome assessments.
• Known hypersensitivity to dapsone or any component of the study product.

Sponsors & Collaborators

• Oya Helin Dundar: lead
• Istanbul Training and Research Hospital: collaborator

Study Sites (1)

Istanbul Training and Research Hospital

Istanbul, 34000, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Acne Vulgaris; Erythema

Interventions

Dapsone; Gels

Condition Hierarchy (Ancestors)

Acneiform Eruptions; Skin Diseases; Skin and Connective Tissue Diseases; Sebaceous Gland Diseases; Skin Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Sulfones; Sulfur Compounds; Organic Chemicals; Colloids; Complex Mixtures; Dosage Forms; Pharmaceutical Preparations

Study Officials

• Oya Helin Dundar, MD

  Istanbul Training and Research Hospital, Dept. of Dermatology

  PRINCIPAL INVESTIGATOR

• Vildan Manav, MD, Assoc. Prof.

  Istanbul Training and Research Hospital, Dept. of Dermatology

  STUDY DIRECTOR

• Ayse Esra Koku Aksu, MD, Prof.

  Istanbul Training and Research Hospital, Dept. of Dermatology

  STUDY CHAIR

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Participants, dispensing investigators, clinical outcome assessors, photographic evaluators, and data analysts were blinded to treatment allocation. Study products were identical in appearance, base, tube, and packaging and were labeled with coded allocation identifiers.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER GOV
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Dermatology Resident Physician

Model Details: Participants were assigned to one of two parallel treatment arms in a 1:1 ratio: topical dapsone 7.5% gel or matched vehicle gel. Treatment was applied once daily for 8 weeks, followed by a 4-week treatment-free follow-up period.

Study Record Dates

• First Submitted: September 10, 2025
• First Posted: November 24, 2025
• Study Start: June 17, 2025
• Primary Completion: February 1, 2026
• Study Completion: March 1, 2026
• Last Updated: May 22, 2026

Record last verified: 2026-05

Locations

TU (1)