INCB028050 Compared to Background Therapy in Patients With Active Rheumatoid Arthritis (RA) With Inadequate Response to Disease Modifying Anti-Rheumatic Drugs

Inclusion Criteria: * Must have rheumatoid arthritis which has been inadequately controlled with at least one DMARD * For subjects receiving antimalarials, they must be treated with antimalarials for at least 6 months and receiving a stable daily dose * For subjects receiving sulfasalazine, they must be treated with Sulfasalazine (SSZ) for at least 6 months and receiving a stable daily dose of no more than 3 grams per day * For subjects on methotrexate, they must be treated with methotrexate for at least 6 months, and receiving a stable weekly dose of methotrexate between 7.5 and 25 mg * For subjects on leflunomide, they must be treated with leflunomide for at least 6 months, and receiving a stable dose of leflunomide between 10 to 20 mg * For subjects receiving corticosteroids, they must be on a dose not to exceed 10 mg of prednisone daily * Active rheumatoid arthritis at the time of screening defined by the following: 6 or more joints tender or painful on motion and 4 or more swollen joints and at least one of the following two: Erythrocyte sedimentation rate (ESR) greater than or equal to 28 mm/hr or C-reactive protein (CRP) greater than or equal to 7 mg/liter * Have evidence of lack of risk for tuberculosis Exclusion Criteria: * Current or recent viral, bacterial, fungal, parasitic or mycobacterial infection requiring systemic therapy * History of infected joint prosthesis * Subjects who have a current or recent history of severe, progressive, uncontrolled renal, hepat…