Safety of Tofacitinib, an Oral Janus Kinase Inhibitor, in Systemic Lupus Erythematosus

* INCLUSION CRITERIA: * Subject is capable of providing written informed consent. * Subject is greater than or equal to 18 years old. * Meets at least 4 of 11 modified American College of Rheumatology (ACR) (1997) Revised Criteria for the Classification of Systemic Lupus Erythematosus. * Has mild to moderate disease activity defined as a SLEDAI 2K more than or equal to 2 and less than or equal to 14 at the screening visit. * If on glucocorticoids, the dose must be less than or equal to 20 mg daily and stable for the 4 weeks prior to screening visit. * If on hydroxychloroquine or other antimalarials such as chloroquine or quinacrine, the dose must have been stable for the 12 weeks prior to screening visit. The maximum allowed dose is hydroxychloroquine up to 400 mg/day or 6.5 mg/kg/day if more than 400 mg/day. The maximum allowed dose for chloroquine phosphate is up to 500 mg daily and for quinacrine up to100 mg daily. * Males and females with potential for reproduction must agree to practice effective birth control measures. Females should be on adequate contraception if they are of child-bearing potential documented by a clinician, unless patients or spouse have previously undergone a sterilization procedure. Adequate will be considered intrauterine device (IUD) alone or hormone implants, hormone patches, injectables, or oral contraceptives plus a barrier method (male condom, female condom or diaphragm), abstinence or a vasectomized partner * If patients are on ACE inhibitors or ARB medications, dose of this medication must be stable for 4 weeks prior to study entry. * Patients may be on lipid lowering medications if initiated at least 6 months prior to the screening visit. EXCLUSION CRITERIA: * Pregnant or lactating women. Women of childbearing potential are required to have a negative pregnancy test at screening. * Current or prior treatment with rituximab, belimumab or any other biologic agent in the 6 months prior to screening. * Current treatment with immunosuppressive drugs (methotrexate, azathioprine, mycophenolate mofetil, cyclosporine, tacrolimus). Glucocorticoids are allowed as per the inclusion criteria. At the investigator s discretion, glucocorticoids may be tapered during the study. * Patients previously on methotrexate, mycophenolate mofetil, cyclosporine or tacrolimus should have stopped it for at least 8 weeks at the time of screening. * Treatment with cyclophosphamide, pulse methylprednisolone or IVIG within the 6 months prior to screening. * Increase in glucocorticoid dose within 4 weeks of screening. * A history of drug or alcohol abuse within the 6 months prior to screening. * History of chronic liver disease or elevated LFTs: * ALT or AST greater than or equal to 2x upper limit of normal at screening * serum unconjugated bilirubin \> 2mg/dL at screening * Dialysis or serum creatinine \>1.5mg/dL. * Protein to creatinine ratio of more than 1 mg/mg or 24 hours urine protein of more than 1000 mg. * Active urinary sediment (WBC, RBC or mixed cellular casts 1+ or more /hpf). * Hypercholesterolemia: Values after an 8-12 hour fasting blood specimen: total cholesterol \>250 mg/dL or LDL \>180 mg/dl or hypertriglyceridemia (triglyceride \>300 mg/dL) within plus or minus 45 days of screening visit. * Active infection that requires the use of oral or intravenous antibiotics and has not resolved at least 2 weeks prior to the administration of the first dose of study medication. * Active chronic infections including but not limited to HIV, Hepatitis B, Hepatitis C, and BK viremia at screening visit. * History of cancer. * Known active tuberculosis or untreated latent tuberculosis. * History of opportunistic infections. * Subjects with active renal or central nervous system disease or a BILAG A in any organ system. * WBC \<2500/Microlitre or ANC \<1,000/Microlitre, Hgb \<9.0 g/dL or platelets \<70,000/Microlitre or absolute lymphocyte count \< 500/Microlitre. * Current treatment with potent inhibitors of Cytochrome P450 3A4 (CYP3A4) (e.g., ketoconazole) or receiving one or more concomitant medications that result in both moderate inhibition of CYP3A4 and potent inhibition of CYP2C19 (e.g., fluconazole) that would increase serum availability of tofacitinib. Past treatment with the above mentioned agent is allowed if it was more than a week prior to the administration of the first dose of study medication. * Significant impairment of major organ function (lung, heart, liver, kidney) or any condition that, in the opinion of the Investigator, would jeopardize the subject s safety following exposure to the study drug.