A Study in Participants With Active Systemic Lupus Erythematosus With Inadequate Response to Glucocorticoids and ≥2 Immunosuppressants

Inclusion Criteria: * Participants must have signed and dated an Institutional Review Board/ Independent Ethics Committee (IRB/IEC)-approved written informed consent form (ICF) in accordance with regulatory, local, and institutional guidelines * Participants must be ≥16 years of age at the time of signing the ICF * Meet the European League Against Rheumatism (EULAR) / American College of Rheumatology (ACR) 2019 classification criteria for systemic lupus erythematosus (SLE) * Have an inadequate response to glucocorticoids and ≥ 2 immunosuppressant therapies, one of which is a biologic therapy consistent with treatment guidelines, used for at least 3 months each. Eligibility is regardless of prior hydroxychloroquine or any anti-malarial treatment. Inadequate response is defined as a lack of response, insufficient response, or lack of sustained response after at least 3-month treatment with appropriate doses of a standard of care agent. Intolerance or contraindication may be considered as inadequate response provided it is documented and confirmed acceptable by the Adjudication Committee * Have active disease at study entry when signing ICF, defined as: * ≥ 1 British Isles Lupus Assessment Group Index (BILAG) A OR ≥ 1 BILAG B with history of SLE manifestations that would qualify for a BILAG A within the last 24 months, AND * Positive autoantibodies (at least one) to confirm diagnosis of SLE: Antinuclear antibody ≥1:160, anti-dsDNA, anti-Sm, anti-Ro (SSA), anti-La (SSB), or…