Inclusion Criteria:

• * Patients between 18 and 65 years old, male or female, of any race
• * Historical presence of at least 4 of 11 of the ACR Classification Criteria
• * Evidence of a positive ANA (≥1:80 titer) or positive dsDNA antibody test within 6 months of screening
• * Clinically active SLE determined by SLEDAI score ≥6 and the presence of at least one BILAG A or BILAG B at screening, despite standard-of-care therapy
• * If the patient has a BILAG A or BILAG B score in the renal organ system, he/she must have completed at least 6 months of therapy for the current episode of nephritis prior to Screening. Therapy must include at least 6 months of mycophenolate or at least 3 months of cyclophosphamide followed by mycophenolate or azathioprine
• * Able and willing to give written informed consent

Exclusion Criteria:

• * Active CNS lupus affecting mental status
• * Active lupus nephritis requiring dialysis
• * Laboratory exclusions: eGFR \<30, WBC \<2.0/mm3, hemoglobin \<8 g/dL, platelet count \<30,000/mm3, liver enzymes AST or ALT \>4 times upper limit normal.
• * Positive testing for HIV, hepatitis B or hepatitis C, tuberculosis (TB), or chest X-ray (CXR) findings consistent with TB or latent fungal infection.
• * History of malignant neoplasm within the last 5 years, except for adequately treated cancers of the skin (basal or squamous cell) or carcinoma in situ of the uterine cervix
• * Pregnant or breast feeding
• * A woman of childbearing potential (not post-menopausal or surgically sterile) who is not willing to use adequate contraception
• * History of renal transplantation
• * Herpes zoster within the past 90 days or any infection requiring hospitalization or intravenous or intramuscular antibiotics within the past 60 days
• * Clinically significant EKG or chest X-ray changes
• * Any other medical condition, related or unrelated to SLE, that in the opinion of the investigator would render the patient inappropriate or too unstable to complete study protocol
• * Use of prednisone \>0.5 mg/kg/day (or equivalent corticosteroid) within 1 month of Baseline visit
• * Change or addition to immunosuppressant regimen within 3 months of Baseline visit (except corticosteroids); Use of other experimental therapeutic agents within 3 months of Baseline visit
• * Having received belimumab within 2 months of Baseline, or having received rituximab or other B cell depleting biologic therapy within 6 months of Baseline.
• * Comorbidities requiring corticosteroid therapy
• * Current substance abuse or recent (within one year) history of substance abuse