A Study to Evaluate the Efficacy of Botulinum Toxin in Patients With Hidradenitis Suppurativa

We will recruit 40 HS patients with an abscess and inflammatory nodule (AN) count ≥5 at a single body site (ex. bilateral axillae, medial thighs). Participants will be randomized 1:1 to receive placebo or 50U of BoNT per 100cm2 of skin (100U total) administered twice over a 6-month study period. Randomization will be stratified by disease stage (Hurley stage <III, III). At baseline and weeks 4, 12, and 24 we will measure disease activity and pain symptom burden using percent change from baseline in abscess and inflammatory nodule (AN) count and draining tunnel (dT) count as the primary outcomes and achievement of ≥ 30% reduction from baseline in the Patient's Global Assessment of Skin Pain Numeric Rating Scale (NRS)-30 as a secondary outcome. The investigators will conduct high-frequency ultrasound measurement of HS tunnel area at baseline and weeks 4,12, and 24 to determine if BoNT therapy can reduce tunnel size. The study team will also collect punch biopsies of lesional skin from HS patients before, and 4 weeks after BoNT treatment then perform flow cytometric, transcriptomic, and microscopic analysis of skin to determine if and how nonselective inhibition of neuropeptide release diminishes HS inflammation.

Inclusion criteria

• age >13 and <75, 2) established or suspected diagnosis of Hidradenitis Suppurativa, 2) HS skin lesions of duration at least 1 year, 3) HS lesions in at least two distinct body areas, 4) inadequate response to a trial of an oral antibiotic or exhibited recurrence after discontinuation of antibiotics, 5) abscess and nodule (AN) count ≥ 5 at baseline, 6) draining tunnel count of <20 at baseline, and 7) ability to provide written informed consent and/or assent.

Exclusion criteria

• Age<13 or >75, 2) pregnant or breastfeeding, 3) history of neuromuscular disorder (ex. ALS, myasthenia gravis, Lambert-Eaton syndrome, myopathy), 4) medical co-morbidity ex. end stage congestive heart failure or coagulopathy that is a relative contradiction to skin biopsy procedure, 5) received systemic steroids or started a new systemic (biologic or non-biologic immunomodulator, oral retinoid) therapy with potential therapeutic impact for HS <12 weeks prior to baseline visit, 6) use of opioid or non-opioid oral analgesics within 14 days of baseline visit (exception: at a stable dose for at least 14 days prior to baseline), 7) receiving anti-IL-17A/F, anti-IL-23, or anti-IL-1 biologic therapy or oral JAK inhibitor, TYK inhibitor, 8) active COVID-19 infection or history of COVID-19 infection within 4 weeks prior tobaseline, 9) oral or IV antibiotic use during the treatment period (exception: stable dose of doxycycline or minocycline upto 100mg PO BID for 28 days prior to baseline and throughout the 6 month treatment and observation period), 10) initiation of topical therapies for HS within 14 days or baseline visit (may continue stable use of topical therapies started > 14 days prior to baseline visit), 11) laser surgery, laser hair removal, or elective surgery to treatment areas within 4 weeks prior to baseline visit, 12) current participation in another clinical study involving the administration of an investigative drug for the treatment of HS, or prior participation in such a study within 60 days prior to baseline visit, 13) active bacterial, fungal, or viral infection in the treatment area at baseline visit, 14) immunocompromised state, 15) known hypersensitivity to botulinum toxin A preparations or any of their components (human albumin, saline, lactose, sodium succinate).