A Study of Obexelimab in Patients with Systemic Lupus Erythematosus

This study consists of a 24-week treatment period followed by a 12-week follow-up period. Patients must have a clinical diagnosis of SLE at least 24 weeks prior to screening and meet the 2019 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) Classification Criteria. To enter the Screening Period (Day -28 to Day -1) patients will have active SLE as defined by having: a) hybrid Systemic Lupus Erythematosus Disease Activity Index (hSLEDAI) ≥ 6 and clinical hSLEDAI ≥ 4, and b) British Isles Lupus Assessment Group (BILAG)-2004 Grade A or B in ≥ 1 organ system. Patients must be treated with one or more of the following background nonbiologic lupus standard of care therapies: oral corticosteroid, antimalarial, and/or immunosuppressant. On Day 1, patients will be randomized 1:1 to obexelimab or placebo subcutaneous (SC) injection once per week (QW) for 24 weeks. All patients will return to the study site for scheduled visits at Week 2, Week 4, and then every 4 weeks thereafter until study completion. During the study, patients will undergo assessments for efficacy, safety, PK, PD, and immunogenicity. Including screening and follow-up, the maximum duration of participation in this study for an individual patient is approximately 40 weeks (i.e., up to a 28-day Screening Period, 24-week Treatment Period, and a 12-week follow-up).