• Males and females, ≥ 18 to ≤ 70 years of age

• Diagnosed with SLE at least 24 weeks prior to screening and meets the 2019 EULAR/ACR classification criteria.

• Patient has all 3 of the following based on features active on the day of the visits:

‣ hSLEDAI ≥ 6 and clinical hSLEDAI ≥ 4 at screening, and clinical hSLEDAI ≥ 4 at Day 1 Note: Clinical points exclude laboratory tests, except proteinuria.

⁃ BILAG-2004 Grade A or B in ≥ 1 organ system at screening and Day 1.

⁃ In the opinion of the investigator and the central adjudicator, there is sufficient disease activity to warrant enrollment into a clinical study with an investigational agent.

• Patients must be treated with one or more of the following background nonbiologic lupus standard of care therapies: oral corticosteroid, antimalarial, and/or immunosuppressant.