Efficacy and Safety Study of Abatacept Subcutaneous Plus Methotrexate in Inducing Remission in Adults With Very Early Rheumatoid Arthritis

Key Inclusion Criteria:

- Presence of active clinical synovitis in at least 2 joints, 1 of which must have been
a small joint, for a minimum of 8 weeks prior to screening

- Onset of persistent symptoms ≤ 2 years prior to screening

- Positive test result for anticyclic citrullinated peptides 2

- Methotrexate naive or with minimum exposure to methotrexate, defined as no more than
10 mg/week for ≤4 weeks and no methotrexate dose for 1 month prior to screening visit

- Biologic naive, including no treatment with an investigational biologic prior to
screening

- Disease Activity Score 28 based on C-reactive protein score ≥3.2 at screening

- Withdrawal from any treatment with chloroquine, hydroxychloroquine, and/or
sulfasalazine (wash-out) for a minimum of 28 days prior to randomization

- If receiving oral corticosteroids, on a stable low dose (≤ 10 mg/day prednisone
equivalent) for at least 4 weeks

- Able to undergo magnetic resonance imaging

Key Exclusion Criteria:

- Meeting diagnostic criteria for other rheumatic disease (eg, lupus erythematosus)

- Treatment with an intravenous, intramuscular, or intraarticular corticosteroid within
4 weeks prior to randomization

- Scheduled for or anticipating joint replacement surgery

- Presence of concomitant illness likely to require systemic glucocorticosteroid
therapy during the study, in the opinion of the investigator

- History of malignancy in the last 5 years

- Any serious bacterial infection within the last 3 months not treated or resolved with
antibiotics, or any chronic or recurrent bacterial infection

- At risk for tuberculosis

- Evidence of active or latent bacterial or viral infection at the time of potential
enrollment, including human immunodeficiency or herpes zoster virus or
cytomegalovirus that resolved less than 2 months prior to enrollment