A Study To Investigate GW274150 Or Prednisolone In Rheumatoid Arthritis Taken Repeatedly For 28 Days.

Inclusion criteria: * Diagnosis of rheumatoid arthritis according to the revised 1987 criteria of the American College of Rheumatology * Female subjects who are not capable of becoming pregnant * Active disease defined as Disease Activity Score (DAS) 28 = 4.0 and at least one metacarpal-phalangeal finger (MCP) joint with either detectable vascularity or thickness * Stable doses of disease modifying anti-rheumatic drugs (DMARDs), (which can include but is not restricted to methotrexate, sulphasalazine and hydroxychloroquine in any combination) for 8 weeks prior to enrollment * Patients receiving methotrexate must be on stable folate supplements * Must have been on stable doses for 2 weeks prior to screening if using COX inhibitors * Signed consent form * The patient is able to understand and comply with protocol requirements, instructions and protocol-stated restrictions Exclusion criteria: * The subject is using, or has used, oral glucocorticoids within 8 weeks of enrollment * The subject is currently receiving anti-rheumatic biological therapy (e.g. infliximab, adalimumab, etanercept or anakinra) * The subject received their final dose of infliximab or adalimumab within 3 months of enrollment * The subject received their final dose of etanercept or anakinra within 1 month of enrollment * The subject has received another investigational drug within 30 days * The subject drinks more than 28 units (male) or 21 units (female) of alcohol in a week * History of liver or renal disease in the 6 months prior to screening * The subject has a history of drug or other allergy * Subject is positive for Hepatitis B and C or HIV virus * The subject has positive pregnancy test * The subject has positive test for drugs of abuse