Botulinum Toxin Therapy in Hidradenitis Suppurativa

Study Overview
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Brief Summary
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This mechanistic observational study will build on data from humans implicating TRPV1 nociceptors in the pathogenesis of the Type-17 chronic inflammatory skin disease Hidradenitis Suppurativa (HS). In this study, the investigators will test the hypothesis that inhibiting neuropeptide activity with botulinum toxin reduces pathogenic IL-17 inflammation, relieves pain, and improves quality of life for HS patients.

Detailed Description
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Botulinum toxin prevents vesicle fusion at nerve terminals thereby inhibiting neuropeptide release. The investigators will collect punch biopsies of lesional skin from HS patients before, and 1-2 months after botulinum toxin treatment (50U per axilla in 10 injections of 0.1mL) then perform flow cytometric, transcriptomic, and microscopic analysis of skin to determine if nonselective inhibition of neuropeptide release diminishes IL-17 driven skin inflammation. The investigators will also assess association between skin inflammation and clinical disease activity, HS-associated itch and pain, and HS-associated quality of life.

Official Title
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Targeting Nociceptors in Hidradenitis Suppurativa

Conditions
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Hidradenitis Suppurativa, Hyperhidrosis

Intervention / Treatment
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* Drug: Botulinum toxin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age between 18-75 established or suspected diagnosis of HS HS skin lesions of duration at least 1 year HS lesions in at least two different body areas Exclusion Criteria: age <18 or >75 pregnant or breastfeeding medical co-morbidity, for example end stage congestive heart failure or coagulopathy, that is a relative contradiction to skin biopsy procedure

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Drug: Botulinum toxin|Standard-of-care administration of botulinum toxin (50 units/axilla injected intradermally) will be performed for routine treatment of Hidradenitis Suppurativa|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Quantification and phenotyping of skin resident dendritic cell, macrophage, and T cell populations in patients before and after intralesional Botox treatment. | immune cell phenotyping | 1-2 months after first treatment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Disease activity | Evaluation of Hidradenitis Suppurativa Clinical Response (HiSCR), a validated outcome measurement that denotes a 50% reduction in total abscess and nodule count relative to baseline after a treatment | 1-2 months | 
| HS-associated pain assessment | Numerical Rating System of HS-associated pain (NRS; 0-10 where 0= no pain, 10= worst pain possible) | 1-2 months | 
| Dermatologic quality of life assessment (SkinDex mini) | Clinical evaluation of the impact of botulinum toxin treatment on HS-related quality of life. The Skindex mini is divided into a 3 question instrument designed to assess symptoms and their impact on emotions and function. QOL in each domain is scored from 0-6 where a lower score indicates a better QOL. | 1-2 months | 
| HS-associated itch assessment | ItchyQuant (scored 0-10 where 0= no itch, 10= worst itch possible) | 1-2 months |