The primary objective of the study is to assess the safety of epratuzumab in patients with SLE.

Inclusion Criteria:

• SL0007 patients who completed through week 12 of the study or who early terminated at week 8 or later due to treatment failure
• Patients must have maintained eligibility requirements throughout their participation in SL0007
• Written informed consent signed prior to initiation of any study-specific assessments at visit 1

Exclusion Criteria:

• Patients may not receive any live vaccination within 2 weeks prior to visit 1 or during the course of the study
• Active severe SLE disease activity which involves the CNS system (defined by BILAG neurologic A level activity) including transverse myelitis, psychosis and seizures
• Active severe SLE disease activity which involves the Renal system (defined by BILAG renal level A activity or Grade III or higher WHO nephritis) or serum creatinine >2.5mg/dL or clinically significant serum creatinine increase within the prior 4 weeks or proteinuria >3.5gm/day
• Patients with a history of anti-phospholipid antibody syndrome AND Use of oral anticoagulants or anti-platelet treatment
• Patients with a history of chronic infection, recent significant infection, or any current sign of symptom that may indicate an infection.