The purpose of this study is to determine the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of SBI-087 in subjects with Systemic Lupus Erythematosus (SLE).

Inclusion Criteria:

• Diagnosis of SLE (by greater than or equal to 4 American College of Rheumatology [ACR] Revised Criteria) greater than 6 months before study day 1.
• History of a positive antinuclear antibody (ANA) titer greater than or equal to 1:160 or equivalent.

Exclusion Criteria:

• Treatment with more than 20 mg of prednisone per day.
• Evidence of unstable clinically significant disease (e.g., cardiovascular, cerebrovascular, respiratory, or renal disease, or any other unstable serious disorder) other than SLE.
• History of cancer (other than resected cutaneous basal and squamous cell carcinoma or in situ cervical cancer) with less than 5 years' documentation of a disease-free state.