A Study to Evaluate the Efficacy and Safety of Mabthera Alone and in Combination With Either Cyclophosphamide or Methotrexate in Patients With Rheumatoid Arthritis

A Randomised, Double Dummy Controlled, Parallel Group Study of the Efficacy and Safety of MabThera (Rituximab) Alone or in Combination With Either Cyclophosphamide or Methotrexate, in Patients With Rheumatoid Arthritis

WA16291 is a Phase IIa "proof-of-concept" study. The primary objective of this study is to determine the safety and efficacy of rituximab (a B cell depleting chimeric monoclonal antibody) used either as monotherapy or in combination with methotrexate or cyclophosphamide in participants with rheumatoid arthritis who have failed prior Disease Modifying Anti-Rheumatic Drug (DMARD) therapy and currently have an inadequate clinical response to methotrexate.

Inclusion Criteria:

• Participants with moderate to severe rheumatoid arthritis (RA) who have previously failed 1-5 DMARDS who currently have partial clinical response to treatment with methotrexate
• Using methotrexate as a single DMARD for at least 16 weeks, of which the last 4 weeks prior to baseline on a stable oral dose greater than or equal to (>=) 10 milligrams per week (mg/week)
• >=21 years of age
• Swollen Joint Count (SJC) and Tender Joint Count (TJC) >= 8 (out of 66 and 68 joints respectively)
• At least 2 of the following parameters at Baseline: C- Reactive Protein >= 15 mg/dL; Erythrocyte Sedimentation Rate >= 30 millimeters per hour (mm/hr); Morning stiffness >45 minutes
• Rheumatoid factor titer >=20 International units per milliliter (IU/mL)
• Corticosteroid (less than or equal to [=<] 12.5 milligrams per deciliter [mg/d] prednisone or equivalent) or Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) are permitted if stable for at least 4 weeks prior to baseline

Exclusion Criteria:

• American Rheumatism Association (ARA) Class IV RA disease
• Concurrent treatment with any DMARD (apart from randomized treatment) or anti-TNF-alpha therapy
• Active infection or history of recurrent significant infection
• Prior history of cancer including solid tumors and hematologic malignancies (except basal carcinoma of the skin that have been excised and cured)
• Evidence of serious uncontrolled concomitant diseases such as cardiovascular disease, nervous system, pulmonary, renal, hepatic, endocrine or gastrointestinal disorders
• Bone/joint surgery within 6 weeks prior to screening
• Rheumatic Autoimmune disease other than RA
• Active rheumatoid vasculitis
• Prior history of gout
• Chronic fatigue syndrome