Study to Evaluate the Pharmacokinetics, Safety and Tolerability of Intravenous Secukinumab in Patients With GCA or PMR

This is a 12-week, open-label, multicenter, basket design study followed by an 8-week follow-up period in two cohorts of participants, one cohort with GCA and one cohort with PMR. This study will consist of 3 phases: screening, treatment and follow-up. Participants will enter a screening period: up to 6 weeks to assess eligibility \[or up to 8 weeks in the event of a major healthcare disruption or a need to complete screening requirements (e.g., required washouts, TB testing, and work up and treatment as needed per local guidelines. Participants will enter a treatment period of 12 weeks: 2 cohorts (GCA and PMR cohorts) receiving total of 3 i.v. doses of Secukinumab (Week 0, Week 4 and Week 8). After treatment participants will enter a follow-up period: 8 weeks treatment-free follow-up (12 weeks after last dose of study treatment). The total duration of the trial for a participant (from screening to follow up) is approximately 26 weeks (maximum of approximately 28 weeks) including safety follow-up.