An Open-label, Time-lagged, Dose-escalation Study to Evalaute the Safety and Efficacy of Subcutaneous Siplizumab in the Treatment of Hidradenitis Suppurativa.

Inclusion Criteria: * Male or Female at least 18 years of age, and provide informed consent prior to study procedures. * Have moderate to severe HS classified as Hurley stage II or III for at least 6 months refractory to conventional therapies with a total AN count of greater than or equal to 5 prior to enrollment/randomization * Failed at least 1 course of oral antibiotics for treatment of HS (or demonstrated intolerance to, or had a contraindication to oral antibiotics for treatment of their HS). * Women of Childbearing potential must have a urine pregnancy test at screening, wk 0 and prior to administration of the study medication * Women of childbearing potential must be willing to continue a highly effective method of birth control throughout the study (oral, injected or implanted hormonal methods of contraception; placement of an intrauterine device or intrauterine system; barrier methods: condom or occlusive cap (diaphragm or cervical/vault caps) plus spermicidal foam/gel/film/cream/suppository (if available in their locale); male partner sterilization (the vasectomized partner should be the sole partner for that participant); true abstinence (when this is in line with the preferred and usual lifestyle of the participant). * Negative screening for tuberculosis (TB) (Quantiferon Gold, T-spot) within 3 months prior to screening * If a positive history of latent tuberculosis: * Currently receiving treatment for latent TB per standard of care * Have documentation of …