A Global Study Comparing Risankizumab to Placebo in Adult Participants With Moderate to Severe Hidradenitis Suppurativa

* Participant with moderate to severe HS for at least 1 year prior to baseline visit. * HS lesions present in at least two distinct anatomical areas. * Draining fistula count of ≤ 20 at Baseline visit. * Total abscess and inflammatory nodule (AN) count of ≥ 5 at Baseline visit. * Participants are required to use a daily antiseptic wash on their HS lesions. * Participant must have a history of inadequate response or intolerance to an adequate trial of oral antibiotics for treatment of HS.

* Participant has a history of active skin disease other than HS that could interfere with the assessment of HS. * Participant has active tuberculosis (TB) or concurrent treatment for latent TB or evidence of hepatitis B virus (HBV) or hepatitis C virus (HCV) or human immunodeficiency virus (HIV) infection. * Participant has prior exposure to anti-interleukin-1 (anti-IL-1) treatment within 3 months or 5 half-lives, whichever is longer, prior to baseline. * Participant has received prescription topical therapies (including topical antibiotics) within 14 days prior to the Baseline visit. * Participant has received systemic non-biologic therapies that can also be used to treat HS within 4 weeks prior to the Baseline visit. * Participant has received any systemic (including oral) antibiotic treatment within 4 weeks prior to the Baseline visit.