Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) to Measure Response to Etanercept in Rheumatoid Arthritis

- Fulfillment of the 1987 American College of Rheumatology (ACR) criteria for RA with a disease duration > 6 months - Presence of active disease (defined as both tender and swollen joints) in at least one wrist - Sub-optimal response to methotrexate (MTX) defined by the presence of the following criteria (based on 68/66 joint count): 8 or more swollen joints AND 8 or more tender joints (with involvement of the wrist, fingers and at least one region outside the hands) at screening - Must be receiving MTX at a stable dose > 15 mg/week at least 12 weeks prior to baseline - a lower dose is acceptable if otherwise not tolerated (toxicity documentation required).

- Patients who are currently receiving disease modifying anti-rheumatic drug (DMARD) therapy (other than MTX, hydroxychloroquine or sulfasalazine) including tumor necrosis factor (TNF) antagonists (etanercept, infliximab, and adalimumab), abatacept, rituximab, leflunomide, cyclosporine, and gold (oral and intramuscular injection) within 8 weeks or 5.5 half-lives, whichever is longer, of screening - Co-existing condition requiring medications that alter vascular flow (e.g., nitrates, calcium channel blockers, ergot containing drugs) [Potential effects of antihypertensive and migraine medications will be discussed with the Sponsor] - Comorbid autoimmune disorders including systemic lupus erythematosus - Unable to undergo an MRI examination (e.g., presence of a pacemaker, defibrillator, or other implanted device such as anterior interbody cages, aneurysm clip or pedicle screws - allergic to contrast agent - tattoos [in area of examination if contains metallic pigment]) - or will likely require sedation for the procedure