Interim efficacy analysis indicated it would be futile to continue study.

The primary purpose of this study is to determine whether abetimus sodium is more effective than placebo in delaying time to renal flare in SLE patients with a history of renal disease.

Inclusion Criteria:

• Diagnosis of Systemic Lupus Erythematosus (SLE)
• Active SLE renal disease within past 4 years.
• Males or females between 12 and 70 years old.
• Females must be non-pregnant and non-lactating. Females and males must use adequate birth control methods during course of study.
• Ability to have weekly intravenous (IV) administration of study treatment.

Exclusion Criteria:

• Active SLE renal disease within past 3 months prior to entering study.
• Use of the following therapies within 3 months prior to entering the study: alkylating agents, e.g., cyclophosphamide, TNF inhibitors, cyclosporine.
• Use of mycophenolate mofetil that exceeds 1000 mg/day, azathioprine that exceeds 100 mg/day, methotrexate that exceeds 10 mg/week, leflunomide that exceeds 10 mg/day within 2 months prior to entering study.
• Use of rituximab within 6 months prior to entering study.
• Current abuse of drugs or alcohol.