Study Conducted in Subjects With Rheumatoid Arthritis Who Have Moderate to Severe Disease Activity Despite Methotrexate Therapy With or Without Other Non Biologic Disease Modifying Antirheumatic Drugs (DMARDs)for at Least 12 Weeks Prior to Screening

Inclusion Criteria:

1. Subject has a minimum 1 year history/diagnosis of rheumatoid arthritis based on the 1987 American College of Rheumatology (ACR) Revised criteria for RA.

2. Subject must have active rheumatoid arthritis despite methotrexate (MTX) therapy of ≥10 mg/wk for at least 12 weeks. The MTX dose must be stable for at least 4 weeksimmediately prior to screening.

Exclusion Criteria:

1. Subjects who used any of the following systemic treatments during the washout periodsgiven below:

2. Oral corticosteroid dose of prednisone >7.5 mg/day (or equivalent) or a change indose within 28 days of baseline.

3. Treatment with more than 1 NSAID within 14 days at baseline.

4. Methotrexate dose greater than 25 mg/week, or change in the dose of methotrexatewithin 28 days of baseline.

5. Subjects will be allowed to continue the following non biologic DMARDs:sulfasalazine, hydroxychloroquine, and leflumomide. All other non-biologic DMARDs (including but not limited to gold, penicillamine, azathioprine,cyclophospamide), and biologic DMARDs must have been discontinued at least 2months prior to Week 1.

6. Any biologic B cell depleting agent (eg, rituximab) within 2 years of Week 1.

7. Receipt of any live (attenuated) vaccine within 4 weeks prior to baseline.

8. Receipt of any live (attenuated) vaccine within 4 weeks prior to baseline.