Inclusion Criteria:
* Adults must have a diagnosis of HS for at least 1 year prior to Baseline.
* HS lesions must be present in at least two distinct anatomical areas, one of which must be at least Hurley Stage II or Hurley Stage III.
* Subject must have stable HS for at least 60 days prior to Screening visit and at Baseline visit.
* Subject must have experienced an inadequate response to at least a 90-day treatment of oral antibiotics for treatment of HS.
* Subject must have a total AN count of greater than or equal to 3 at baseline.
Exclusion Criteria:
* Subject was previously treated with adalimumab or another anti-tumor necrosis factor (anti-TNF) therapy (e.g., infliximab or etanercept).
* Subjects on permitted oral antibiotic treatment for HS who have not been on a stable dose for at least 28 days prior to the Baseline visit.
* Subject received oral concomitant analgesics (including opioids) for HS-related pain within 14 days prior to Baseline visit.
* If entering the study on concomitant oral analgesics for non-HS related pain:
* Subject on opioid analgesics within 14 days prior to Baseline visit;
* Subject not on a stable dose of non-opioid oral analgesics for at least 14 days prior to the Baseline visit ("as needed" is not considered a stable dose).
