Effects of Abrocitinib Treatment on Skin Barrier Function

Study Overview
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Brief Summary
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Effects of abrocitinib treatment of atopic dermatitis on skin barrier function.

Detailed Description
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Open-label, non-randomized, single-arm, 12-weeks observational clinical and translational study

Official Title
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Effects of Abrocitinib Treatment of Moderate to Severe Atopic Dermatitis on Skin Barrier Function

Conditions
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Atopic Dermatitis

Intervention / Treatment
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* Other: No Intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Written informed consent obtained from the subject prior to performing any protocol-related pro-cedures, including screening evaluations Age ≥ 18 years at time of study entry. Diagnosis of chronic atopic dermatitis for at least 1 year prior to enrollment based on American Academy Criteria Eczema Area and Severity Index (EASI) score ≥12 at baseline visit (Week 0) Investigator Global Assessment (IGA) ≥3 at baseline visit (Week 0) Subject is willing and able to comply with the protocol for the duration of the study Subject receives abrocitinib by the treating dermatologist within routine care Exclusion Criteria: 1. Subject is unable to provide written informed consent or comply with the protocol Concurrent enrolment in another clinical trial where the subject is receiving an IMP or participation in another clinical trial with investigational product during the last 30 days before inclusion or 7 half-lives of previously used trial medication, whichever is longer. Active dermatologic conditions that may confound the diagnosis of AD or would interfere with as-sessment of treatment, such as scabies, cutaneous lymphoma, or psoriasis. Known active allergic or irritant contact dermatitis that is likely to interfere with the assessment of severity of AD. Having used systemic immunosuppressive/immunomodulating therapy (e.g. systemic corticoster-oids methotrexate, cyclosporine, azathioprine, mycophenolate mofetil, JAK inhibitors) or tanning beds or phototherapy during any week within the 4 weeks or receipt of any marketed biologic ther-apy (e.g., dupilumab, tralokinumab) within 3 months or 5 half-lives, whichever is longer, prior to baseline Treatment of selected marker skin areas (non-lesional skin at volar forearm and extensor forearm, lesional skin) with topical corticosteroid or topical calcineurin inhibitor 1 week prior to baseline visit and throughout the study. Treatment of skin areas of examination with emollients 24 hours prior to baseline visit and throughout the study. Involvement in the planning and/or conduct of the study.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| AbroSkib Cohort<br>Adult patients with moderate to severe atopic dermatitis who are eligible for and will receive systemic therapy with abrocitinib by their treating dermatologist as part of standard healthcare (n=20). The choice of therapy is strictly done by the treating dermatologist only, and the reasons for the choice will be captured by a structured documentation. | Other: No Intervention<br>* Non Interventional<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in transepidermal water loss (TEWL) at one non-lesional and one lesional marker skin area at week 2 and week 12 compared to baseline/week 0 (day 0). | To determine the mean change of TEWL in g/m2/h at one non-lesional and one lesional marker skin site at week 2 and week 12 compared to baseline | 12 Weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of epidermal barrier-related genes/pathways differentially expressed in a marker lesional skin site at week 2 and week 12 compared to baseline | To compare the expression of epidermal barrier-related genes at the transcriptome level at a marker lesional skin site at week 2 and week 12 to baseline and to non-lesional skin | 12 Weeks | 
| Epidermal thickness and epidermal differentiation markers in a marker lesional skin site at week 2 and week 12 compared to baseline | To compare epidermal thickness (in µm) and the percentage of marker-positive cells (KRT 16, Ki67, FLG) in a marker skin site with reference to the number of cells in the basal layer at week 2 and 12 to baseline and to non-lesional skin | 12 Weeks | 
| Stratum corneum biomarker (cytokine) levels (pg/μg protein) in marker skin sites at week 2 and week 12 compared to baseline | To compare stratum corneum biomarker (cytokine) levels (pg/μg protein) in a marker lesional skin site at week 2 and week 12 compared to baseline and to non-lesional skin | 12 Weeks | 
| Composition of Bacterial Taxa of one lesional and non-lesional marker skin area at week 2 and week 12 compared to baseline | To identify changes in community composition and diversity at one lesional and one non-lesional marker skin site at week 2 and week 12 as compared to baseline using Next Generation Sequencing techniques | 12 Weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Skin Barrier, Atopic Dermatitis, Dermatology, Skin Physiology