The purpose of this study is to find out if 300 mg of BMS-582949 given once daily will be more effective than placebo after 12 weeks of treatment in subjects with rheumatoid arthritis who are also taking methotrexate

Inclusion Criteria:

• Must have a diagnosis of RA for at least 6 months
• Must be taking methotrexate for at least 3 months & on a stable dose of 7.5-30 mg weekly) for 4 weeks before dosing with study medication
• Must have at least 6 swollen and at least 8 tender joints
• CRP above upper limit of normal or ESR > 28 mm/hr
• Must wash-out (stop taking) other immunosuppressant medications to treat RA (except for methotrexate) before dosing with study medication

Exclusion Criteria:

• Any infection including TB, HIV, Hepatitis B or C
• Recent infection requiring antibiotics within 4 weeks
• History of gastrointestinal disease (such as GERD, gastrointestinal ulcers, heartburn) requiring medical or surgical treatment within 3 months
• Chronic use of proton pump inhibitors (such as Losec, Prilosec, Prevacid, Nexium), H2 blockers (such as Tagamet, Pepcid, Zantac, Axid) or antacids (such as Mylanta, Maalox)