Botulinum Toxin Type B for Hidradenitis Suppurativa: A Randomised, Double-Blind, Placebo-Controlled Pilot Study.

[BACKGROUND] Botulinum toxin (BTX) is a potent neurotoxin with a long history of therapeutic application in neurological and dermatological conditions, with a strong efficacy and safety profile.

[OBJECTIVE] Our aim was to assess whether intradermal injection with BTX-B is an effective treatment for hidradenitis suppurativa (HS).

[METHODS] Twenty patients with HS stage I-III disease, according to Hurley's classification, were consecutively included for treatment with either a placebo or BTX-B. At the next intervention after 3 months, all participants received the active substance and another follow-up at 6 months. The primary outcome was quality of life, measured using the Dermatology Life Quality Index (DLQI), while secondary outcomes were the visual analogue scale (VAS) for pain in the worst boil and HS-related impairment of general health (VAS), as well as changes in physician-reported disease activity assessed as the number of total lesions, and reported adverse effects of treatment.

[RESULTS] The DLQI improved from a median of 17 at baseline to 8 at 3 months in the BTX-B group, compared with a reduction from 13.5 to 11 in the placebo group (p <0.05). Improvement of the patients' own ratings of symptoms and a reduction in total lesions supplemented the primary outcome. Fifty-five percent of the study population reported some degree of hyperhidrosis.

[CONCLUSION] BTX-B improves the quality of life in patients with HS. Furthermore, comorbidity between HS and hyperhidrosis is suggested.

[TRIAL REGISTRATION] ClinicalTrials.gov identifier: NCT03103074.