Safety, Tolerability, and Pharmacodynamic Study of ISIS CRP Rx in Rheumatoid Arthritis

Inclusion Criteria: * Male or female; age 18 to 75 years * Active RA for at least 6 months * Active disease defined by having equal to or greater than 6 swollen joints and 6 tender joints, based on a 28 joint count * On stable doses and regimen of allowed RA medications * Currently receiving at least 10 mg of methotrexate a week. Patients unable to tolerate doses greater than 10 mg may also be eligible for enrollment. Exclusion Criteria: * Diagnosis of Felty's syndrome, psoriatic arthritis, gout, or auto-immune rheumatic disease * Any surgical procedure within 30 days of Screening or likely to need joint or tendon surgery or other surgical procedure during the study * Intra-articular or intra-muscular corticosteroids within 60 days prior to dosing * Previous treatment with any biologic response modifying agent for RA within 90 days or 5 half-lives, whichever is greater, prior to screening * Previous treatment with rituximab at any time * Use of corticosteroid therapy equivalent to an average daily dose of \>10 mg of prednisone * Any Screening laboratory values that are out of allowed reference ranges * Inability to comply with protocol or study procedures * Any other significant illness or condition that may adversely affect the subjects participation in the study