An International, Multicenter, Randomized, Double-Blind, Parallel Group, Vehicle-Controlled, Phase 2/3 Study With Open-Label Extension Evaluating the Efficacy and Safety of Diacerein 1% Ointment for the Treatment of Generalized Epidermolysis Bullosa Simplex (EBS) (EBShield)

An International, Multicenter, Randomized, Double-Blind, Parallel Group, Vehicle-Controlled, Phase 2/3 Study With Open-Label Extension Evaluating the Efficacy and Safety of Diacerein 1% Ointment for the Treatment of Generalized Epidermolysis Bullosa Simplex (EBS) [EBShield Study]

The proposed Phase 2/3 trial with double-blind and open-label extension phases is an international, multicenter study designed to assess the efficacy and safety of diacerein 1% ointment in patients with generalized EBS.

Study Overview

• Status: Active, not recruiting
• Conditions: Generalized Epidermolysis Bullosa Simplex
• Intervention / Treatment: Drug: AC-203; Drug: Vehicle

Detailed Description

Epidermolysis bullosa simplex (EBS) is a genetic skin disorder characterized by skin fragility and recurrent blister formation, primarily caused by mutations in keratins 5 and 14. EBS has 3 common subtypes based on clinical severity and manifestations: localized EBS, intermediate EBS and severe EBS. Severe EBS and intermediate EBS collectively are also known as generalized EBS due to widespread blistering.

Disruption of the keratin 5/14 filament network in basal keratinocytes is a key factor in EBS pathogenesis, compromising skin integrity. The severity of EBS is linked to the extent of keratin mutations disrupting this network, particularly resulting in keratin aggregates in severe cases. Recent studies suggest that mutated keratin proteins can trigger inflammation, exacerbating EBS. Elevated proinflammatory cytokines, like IL-1β and IL-6, are observed in EBS patients, and IFN-γ may mediate inflammation, promoting keratin aggregations. As a result, targeting inflammation is considered a potential therapeutic approach in EBS.

AC-203 (diacerein 1% ointment) is a topical formulation of diacerein, well-known for its ability to inhibit IL-1β and other proinflammatory cytokines. Moreover, diacerein and its active metabolite, rhein, have demonstrated ability in reducing keratin aggregates in keratinocytes derived from severe EBS. Taken together, with its anti-inflammatory property and ability to diminish keratin aggregation, AC-203 shows promise in reducing the clinical severity of EBS.

• Study Type: Interventional
• Enrollment (Estimated): 80
• Phase: Phase 2; Phase 3

Contacts and Locations

Study Locations

• Australia
  • Kogarah, Australia
    • Premier Specialists
  • Randwick, Australia
    • Sydney Children's Hospital
• Austria
  • Salzburg, Austria
    • Universitaetsklinik fuer Dermatologie und Allergologie
• Belgium
  • Leuven, Belgium
    • UZ Leuven
• China
  • Guangdong
    • Guangzhou, Guangdong, China
      • Dermatology Hospital of Southern Medical University
• Greece
  • Thessaloniki, Greece
    • Hospital Of Skin And Venereal Diseases of Thessaloniki
• India
  • Chandigarh, India
    • Postgraduate Institute of Medical Education and Research (PGIMER)
• Ireland
  • Dublin, Ireland
    • Children's Health Ireland
• Israel
  • Tel Aviv, Israel
    • Tel Aviv Sourasky Medical Center
• Italy
  • Milan, Italy
    • Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano
  • Modena, Italy
    • Università degli Studi di Modena e Reggio Emilia (UNIMORE)
  • Rome, Italy
    • Istituto Dermopatico dell'Immacolata (IDI) - Istituto di
  • Rome, Italy
    • UOS "Centro delle Dermatosi Croniche Complesse e Genodermatosi" UOC Dermatologia
• Malaysia
  • Kuala Lumpur, Malaysia
    • Hospital Tunku Azizah (Hospital Wanita Dan Kanak-kanak Kuala Lumpur)
• Philippines
  • City of Muntinlupa, Philippines
    • Asian Hospital
  • Iloilo City, Philippines
    • Iloilo Doctors Hospital
  • Mandaluyong, Philippines
    • Health Cube Medical Clinics
• Poland
  • Warsaw, Poland
    • OT.CO Clinic Osipowicz & Turkowski
• South Korea
  • Seoul, South Korea
    • Gangnam Severane Hospital
• Spain
  • Madrid, Spain
    • Hospital Universitario La Paz
• Taiwan
  • Tainan, Taiwan
    • National Cheng Kung University Hospital
• United Arab Emirates
  • Abu Dhabi, United Arab Emirates
    • Sheikh Khalifa Medical City (SKMC)
• United Kingdom
  • London, United Kingdom
    • Great Ormond Street Hospital (GOSH) for Children NHS Foundation Trust - Somers Clinical Research Facility (CRF)
• United States
  • California
    • Rancho Santa Margarita, California, United States, 92688
      • Mission dermatology Center
    • Stanford, California, United States, 94304
      • Stanford University
  • Colorado
    • Aurora, Colorado, United States, 80045
      • Children's Hospital Colorado
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Northwestern University - Lurie Childrens's Hospital
  • Ohio
    • Cincinnati, Ohio, United States, 45229
      • Cincinnati Childrens Hospital
  • South Carolina
    • Charleston, South Carolina, United States, 29425
      • Medical University of South Carolina
  • Texas
    • San Antonio, Texas, United States, 78218
      • Texas Dermatology and Laser Specialists

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Patient is at least 6 months old at Visit 2 (Day 1/Baseline A).
2. Patients has been clinically diagnosed with severe EBS or intermediate EBS, confirmed by documented genetic diagnosis to have autosomal dominant mutations in KRT5 or KRT14 gene.
3. Patient with ≥ 3% BSA of EBS lesions excluding palms and soles at Visit 2 (Day 1/Baseline A).
4. Patient's EBS lesions within the Treatment Area have an IGA score of ≥3 at Visit 2 (Day 1/Baseline A).
5. Patient/caregiver agrees to follow study medication application instructions.
6. Patient (and caregiver/legal guardian) agrees to report use of all prescription and over-the-counter medications, including topical therapies applied to the body, e.g., medical cleansers, bleach cleansers, bleach baths, topical antiseptics, topical disinfectants, etc. for the duration of the study.
7. Patient (and caregiver/legal guardian) is willing and able to comply with all study visits and all the protocol requirements, including completing questionnaires.
8. Patient (and caregiver/legal guardian) is able to provide written informed consent; assent based on age.
9. Female patient of childbearing potential must have a negative pregnancy test prior to randomization.
10. Female patient of childbearing potential is willing to practice highly effective contraception (i.e., pregnancy prevention method with a failure rate of < 1% per year) from Screening throughout the end of the study.

Exclusion Criteria:

1. Patient has a clinically significant skin disease other than EBS (e.g., psoriasis, atopic dermatitis, eczema, sun damage, etc.), or a vascular disorder associated with cutaneous erosions/ulcerations, that may confound assessments of efficacy or safety.
2. Patient has a clinically significant underlying medical condition, psychiatric condition (such as major depressive or psychotic disorder, severe intellectual disability, or alcohol or drug use disorder), or requires concomitant medication that based on the investigator's judgement may impair evaluation of the Treatment Area or exposes the patient to an unacceptable risk by study participation.
3. Patient has used any diacerein-containing product within 6 months prior to Visit 2 (Day 1/Baseline A).
4. Patient has had a cutaneous infection in the Treatment Area or use systemic antibiotics within 7 days prior to Visit 2 (Day 1/Baseline A).
5. Patient has uncontrolled diabetes mellitus (HbA1c ≥ 6.5%), hepatic enzyme abnormalities (alanine aminotransferase or aspartate aminotransferase >2.5 the upper limit of normal (ULN), or total bilirubin >2.0x ULN), or renal abnormalities (estimated glomerular filtration rate [eGFR]< 30 ml/min/1.73 m2) during the Screening period.
6. Patient has a current malignancy, or a history of treatment for a malignancy within 5 years (with the exception of treated non-melanoma cutaneous malignancy e.g., surgically resected with clear margins) prior to Visit 2 (Day 1/Baseline A).
7. Patient is treated with protocol-excluded topical therapies other than steroids within 2 weeks prior to Visit 2 (Day 1/Baseline A) that might influence the assessment of the Treatment Area throughout the study period.
8. Patient has been treated with topical steroids on the EBS lesions within 2 weeks or systemic steroids within 4 weeks. prior to Visit 2 (Day 1/Baseline A). (Note: inhaled and ophthalmic products containing steroids are allowed.)
9. Patient has been treated with: (a) an approved biologic anti-inflammatory therapy (such as monoclonal antibodies that target to modulate the immune responses) and (b) other immunosuppressive/immunomodulatory therapies or chemotherapy within 8 weeks prior to Visit 2 (Day 1/Baseline A).
10. Patient has been treated with any investigational drug or device within 30 days or 5 half-lives, whichever is longer, prior to Visit 2 (Day 1/Baseline A).
11. Patient has a history of allergy or hypersensitivity to any component of study medications, including diacerein or rhein.
12. Patient is pregnant or breastfeeding/lactating.
13. Patient has a planned or anticipated major surgical procedure or other activity that would interfere with their ability to comply with protocol requirements.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Part A AC-203; Double-blind, AC-203 Diacerein 1% ointment, QD	Drug: AC-203; The investigational product is formulated as 1% topical ointment
Placebo Comparator: Part A Vehicle ointment; Double-blind, Vehicle ointment, QD	Drug: Vehicle; Vehicle-only control study medication is the same formulation as investigational product without active ingredient
Experimental: Part B AC-203; Open-label extension phase, AC-203 Diacerein 1% ointment, QD	Drug: AC-203; The investigational product is formulated as 1% topical ointment

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of patients achieving treatment success on the IGA of the Treatment Area, in which treatment success is defined as a score of 0 or 1 with at least a 2-point reduction	The static IGA is the investigator's visual clinical assessment of the average overall intensity of lesions in the designated Treatment Area at a particular time point. EBS-IGA is a 5-point scale is a 5-point scale (clear=0; almost clear=1; mild=2; moderate=3; severe=4)	from Baseline A (Visit 2/Day 1) to Week 8 (Visit 5/EOT)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in % BSA of EBS lesions in the Treatment Area	The Body Surface Area (BSA) of the Assessment Area will be collected for all lesions included within the Treatment Area using the palmar method	from Baseline A (Visit 2/Day 1) to Week 8 (Visit 5/EOT)
Change in the QOLEB score	The Life Epidermolysis Bullosa (QOLEB) questionnaire is a valid and reliable, EB-specific QOL measurement tool, for the quantification of QOL in patients with various subtypes of EB, including EBS. It consists of 17 questions with four response choices from "not at all" to "constant"	from Baseline A (Visit 2/Day 1) to Week 8 (Visit 5/EOT)
Change in EBDASI score (skin activity)	The EBDASI is a valid and reliable EB-specific outcome measurement tool to assess the overall extent of disease activity and damage in patients with various subtypes of EB, including EBS. Section I (skin), the severity of disease, including erosion/blisters/crusting etc., will be measured at 12 different skin sites.	from Baseline A (Visit 2/Day 1) to Week 8 (Visit 5/EOT).
Change in pain intensity score	Wong-Baker FACES® Pain Rating Scale will be used for patients 3 years and older.	Baseline A (Visit 2/Day 1) to Week 8 (Visit 5/EOT)
Change in pruritus intensity score	ItchyQuant will be used for patients aged 6 years and older, including adult patients	from Baseline A (Visit 2/Day 1) to Week 8 (Visit 5/EOT)

Collaborators and Investigators

• Sponsor: TWi Biotechnology, Inc.

Study record dates

Study Major Dates

• Study Start (Actual): April 4, 2024
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): March 1, 2027

Study Registration Dates

• First Submitted: September 12, 2023
• First Submitted That Met QC Criteria: October 3, 2023
• First Posted (Actual): October 10, 2023

Study Record Updates

• Last Update Posted (Actual): April 24, 2026
• Last Update Submitted That Met QC Criteria: April 23, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: EBS; Epidermolysis Bullosa Simplex
• Additional Relevant MeSH Terms: Genetic Diseases, Inborn; Skin Diseases; Congenital Abnormalities; Skin Diseases, Genetic; Skin Abnormalities; Skin Diseases, Vesiculobullous; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Skin and Connective Tissue Diseases; Epidermolysis Bullosa; Epidermolysis Bullosa Simplex; diacerein
• Other Study ID Numbers: AC-203-EBS-007

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No