Lead Sponsor

University of California, Los Angeles

Age

18 - No limit years

Sex

ALL

Healthy Volunteers

No

•1. Over 18 years old
•2. Has a diagnosis of rheumatoid arthritis
•3. Stable DMARDs for at least 1 month (methotrexate, leflunomide, hydroxychloroquine, or sulfasalazine)
•4. Disease activity score DAS28/ESR \> 3.2 or all must be met: TJC (tender joint count)\>=4, SJC (swollen joint count)\>=4
•5. Must be able to understand information in the Informed Consent and comply with study requirements
•6. Total ultrasound synovitis (inflammation of joint-lining membrane) power Doppler score \>=1 for at least 2 joints and total synovitis score \>=1 for at least 1 joint

•1. Current or prior use of biologic drugs (TNF inhibitors, IL-6 inhibitors, CD20 inhibitors, IL-1 inhibitors, etc.)
•2. Pregnancy or breast feeding
•3. Daily prednisone \> 10mg (stable dose for at least 1 month)
•4. Intra-articular steroid injection of the wrist or joints within last 2 months
•5. History of a concomitant autoimmune disease such as lupus, psoriatic arthritis
•6. History of cancer
•7. Previous exposure to abatacept