This parallel-group, double-blind, placebo-controlled study will evaluate the efficacy and safety of obinutuzumab versus placebo in participants with active, autoantibody-positive systemic lupus erythematosus (SLE) who are treated with standard-of-care therapy.

Inclusion Criteria:

• Diagnosis of SLE according to the 2019 European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) Classification Criteria >=12 weeks prior to screening
• Anti-nuclear antibody (ANA) >=1:80, or anti-dsDNA and/or anti-Sm antibodies above the upper limit of normal (ULN), as determined by the central laboratory at screening
• Low C3 or low C4 or low CH50 complement as determined by the central laboratory at screening
• High disease activity at screening, based on; BILAG-2004 (Category A disease in >=1 organ system and/or Category B disease in >=2 organ systems), Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) (score >=8) and Physician's Global Assessment (PGA) (score >=1.0 on a 0 to 3 visual analogue scale [VAS])
• High disease activity on Day 1, based on; SLEDAI-2K (score >=8) and PGA (score >=1.0 on a 0 to 3 VAS)
• Current receipt of >=1 of the following classes of standard therapies for the treatment of SLE at stable doses: oral corticosteroid (OCS), antimalarials, conventional immunosuppressants
• Other inclusion criteria may apply
• The Medical Monitor may be consulted if there are any questions related to eligibility criteria

Exclusion Criteria:

• Pregnancy or breastfeeding
• Presence of significant lupus-associated renal disease and/or renal impairment
• Receipt of an excluded therapy, including any anti-CD20, anti-CD19 therapy less than 9 months prior to screening or during screening; or cyclophosphamide, tacrolimus, ciclosporin, or voclosporin during the 2 months prior to screening or during screening
• Significant or uncontrolled medical disease which, in the investigator's opinion, would preclude patient participation
• Known active infection of any kind or recent major episode of infection
• Intolerance or contraindication to study therapies
• Other exclusion criteria may apply

For eligible studies, qualified researchers may request access to individual patient level clinical data. See Roche's commitment to transparency of clinical study information here: https://go.roche.com/data\_sharing