A Study of the Safety of Rituximab in Combination With Other Anti-Rheumatic Drugs in Subjects With Active Rheumatoid Arthritis

Inclusion Criteria (Stage I):

• Male or female subjects, between 18 and 80 years of age, who have a documented diagnosis of active rheumatoid arthritis (RA) for ≥ 6 months
• Receiving treatment for RA on an outpatient basis
• Have had an inadequate response to at least one non-biological disease-modifying anti-rheumatic drug (DMARD) and have been receiving this DMARD(s) for ≥ 12 weeks prior to baseline, with stable dose greater than or equal to 4 weeks prior to baseline
• Demonstrated tolerability to currently prescribed DMARDs
• If taking a background corticosteroid, use of the corticosteroid must be at a stable dose during the 4 weeks prior to the first day of treatment with rituximab (Day 1)
• Use of one nonsteroidal anti-inflammatory drug (NSAID) is permitted if the dose is stable for ≥ 2 weeks prior to Day 1

Exclusion Criteria (Stage I):

• Rheumatic autoimmune disease other than RA or significant systemic involvement secondary to RA (including but not limited to vasculitis, pulmonary fibrosis, or Felty's syndrome)
• Functional Class IV as defined by the American College of Rheumatology (ACR) Classification of Functional Status in Rheumatoid Arthritis
• History of or current inflammatory joint disease other than RA or other systemic autoimmune disorder
• Diagnosis of juvenile idiopathic arthritis, or juvenile RA, and/or RA before age 16 years
• Any surgical procedure, including bone/joint surgery/synovectomy (including joint fusion or replacement) within 12 weeks prior to baseline or planned within 24 weeks of enrollment
• Lack of peripheral venous access
• Significant cardiac or pulmonary disease (including obstructive pulmonary disease)
• Evidence of significant uncontrolled concomitant disease such as, but not limited to, nervous system, renal, hepatic, endocrine, or gastrointestinal disorders that, in the investigator's opinion, would preclude subject participation
• Primary or secondary immunodeficiency (history of or currently active), including known history of human immunodeficiency virus (HIV) infection
• Known active infection of any kind (excluding fungal infections of nail beds), or any major episode of infection requiring hospitalization or treatment with intravenous (IV) antibiotics within 4 weeks of baseline or completion of oral antibiotics within 2 weeks prior to baseline
• History of medically significant opportunistic infection
• History of serious recurrent or chronic infection
• History of deep space/tissue infection within 52 weeks prior to baseline
• History of cancer, including solid tumors, hematologic malignancies, and carcinoma in situ (except basal cell and squamous cell carcinoma of the skin that have been excised and cured)
• History of significant cytopenias or other bone marrow disorders
• History of alcohol, drug, or chemical abuse within 24 weeks prior to baseline
• Pregnancy or lactation
• Neuropathies and neurovasculopathies that might interfere with pain evaluation
• Methotrexate (MTX) monotherapy at the time of screening
• Concurrent treatment with MTX and leflunomide in combination
• Concurrent treatment with any biologic agent
• Prior to Day 1, subjects will be discontinued from all DMARDs/combinations that are prohibited in the protocol
• History of a severe allergic or anaphylactic reaction to a biologic agent, or known hypersensitivity to any component of rituximab or to murine proteins
• Previous treatment with an anti-α4 integrin agent
• Previous treatment with any cell-depleting therapies, including investigational agents
• Receipt of any vaccine within 28 days prior to baseline
• Intolerance or contraindications to IV corticosteroids
• Receipt of IV immunoglobulin (IVIG) or Prosorba column within 6 months prior to baseline
• Any previous treatment with rituximab
• Positive hepatitis B surface antigen, hepatitis B core antibody, or hepatitis C antibody

Inclusion Criteria (Stage II):

• Male or female subjects, between 18 and 80 years of age, who have a documented diagnosis