• Diagnosis of moderate to severe HS for at least 3 months prior to the screening visit.

• Total abscess and inflammatory nodule count of at least 5 at both the screening and baseline visits

• HS lesions in at least 2 distinct anatomical areas (examples include but are not limited to left and right axilla or left and right inguinocrural fold), 1 of which must be at least Hurley Stage II or Hurley Stage III, at both the screening and baseline visits

• Documented history of inadequate response to at least a 3-month course of at least 1 conventional systemic therapy (oral antibiotic or biologic drug) for HS (or demonstrated intolerance to, or have a contraindication to, a conventional systemic therapy for treatment of their HS).

• Agreement to NOT use topical and systemic antibiotics for treatment of HS during the placebo-controlled period.

• Agreement to NOT use a diluted bleach bath or topical antiseptic washes containing chlorhexidine gluconate or benzoyl peroxide on the areas affected by HS lesions during the placebo-controlled period. Note: Over-the-counter soap and water is allowed.

• Agreement to use contraception

• Willing and able to comply with the study protocol and procedures.

• Further inclusion criteria apply.