Safety and Pharmacokinetics of Repeat Doses of CSL324 in Subjects With Hidradenitis Suppurativa and Palmoplantar Pustulosis

Inclusion Criteria: * Male or female subjects between 18 and 75 years of age, inclusive * Confirmed clinical diagnosis of moderate to severe HS as per International Hidradenitis Suppurativa Severity Score System (IHS4) guidelines (ie, IHS4 ≥ 4) * PPP differentiated from other forms of pustulosis * Psoriasis with a Palmoplantar Pustulosis Psoriasis Area and Severity Index (ppPASI) score of ≥ 12. * Subjects with HS only: inadequate response to at least a 3-month (90 days) trial of oral antibiotics for treatment of HS * Subjects with PPP only: confirmed clinical diagnosis of PPP at least 6 months before Screening and inadequate response to topical therapy, phototherapy, and / or previous systemic therapy for the treatment of PPP Exclusion Criteria: * Treatment with any medications and therapies not permitted during the study. * History of myeloproliferative disease. * Malignancy within 5 years at Screening with the exception of nonmelanoma skin cancer, carcinoma in situ, or prostate cancer not requiring treatment. * Current, or a recent clinically significant history of, uncontrolled renal, hepatic(including currently active hepatitis B virus and / or hepatitis C virus), hematologic, endocrine, pulmonary, psychiatric, or cardiac disease, assessed as potentially having an effect on study outcomes as determined by the Investigator and / or Sponsor. * Congenital or acquired immunosuppressive condition(s), including human immunodeficiency virus infection. * Clinical signs of active infection and / or fever \> 38°C during the 7 days before Day 1. * Clinically significant abnormalities on physical examination, ECG, or laboratory assessments, or neutropenia (defined as absolute neutrophil count \< 2.0 × 109/L) at Screening. * Subjects with PPP only: concurrent psoriasis vulgaris (not including scaly scalp and / or ears). * Subjects with HS only: \> 20 draining fistulas."