SB-681323 In Subjects With Rheumatoid Arthritis

Inclusion Criteria: Females cannot be pregnant or lactating. Must use defined contraceptive methods if of child-bearing potential. BMI range: 18.5-35.0 kg/m2. Diagnosis of RA (rheumatoid arthritis) according to revised 1987 American College of Rheumatology (ACR) criteria. If other RA-medication is used: Disease-Modifying Anti-Rheumatic Drug (DMARDS) must be stable for at least 8 weeks before first trial visit. If other oral anti-RA therapies are used, these must have been stable at least 4 weeks before first trial visit. If Methotrexate medication is used as RA-therapy, Folate supplement must be taken with stable red cell folate levels. Must give informed consent. Must abstain from alcohol during the trial participation. Exclusion Criteria: Non-responder on biological RA treatment. Has a positive alcohol screen. Any history of liver disease. Positive Hepatitis B surface antigen or Hepatitis C antibody result within 3 months of screening. Have any significant disease that places the subject at unacceptable risk as a participant in this trial. Acute infection. History of active tuberculosis. History of repeated or chronic infection. History of malignancy. History of HIV or other immunosuppressive diseases. Participated in a clinical trial within the last 3 months for non-biological therapies and 6 months for biological therapies. Uncontrolled diabetes or psoriasis.