Study Evaluating The Efficacy And Safety Of SBI-087 In Seropositive Subjects With Active Rheumatoid Arthritis

Inclusion Criteria:

- Meets the American College of Rheumatology (ACR) 1987 revised criteria for
classification of Rheumatoid Arthritis (RA) for at least 6 months prior to screening

- Active RA as defined by >= 5 swollen and >= 5 tender joints (28-joint count) and at
least 1 of the following: C-reactive protein >= 10 mg/L or Erythrocyte Sedimentation
Rate >= 28 mm/h

- Must be seropositive as defined by a documented history of rheumatoid factor (RF) or
anti-cyclic citrullinated peptide (anti-CCP) positivity

- Must be receiving a stable route and dose of methotrexate (up to 25 mg weekly)

Exclusion Criteria:

- Any significant health problem other than rheumatoid arthritis

- Any clinically significant laboratory abnormalities

- Any prior use of B cell-depleting therapy