BG9924 in Combination With Methotrexate for Participants With Active Rheumatoid Arthritis

Key Inclusion Criteria: * Diagnosis of rheumatoid arthritis (functional class I - III) at least 6 months prior to baseline * Methotrexate (10 mg/week to 25 mg/week) \> 3 months prior to Day 0 (stable dose \> 4 weeks prior to Day 0) * Must have had an inadequate response to anti-TNF therapy due to inadequate efficacy Key Exclusion Criteria: Medical History * Serious local infection or systemic infection within 3 months of Day 0 * History (Hx) of recurrent infections requiring oral or parental anti-infective treatment * Hx of tuberculosis (TB) or positive purified protein derivative (PPD) test during the screening period Laboratory Tests * Clinically significant lab tests at screening; or * Positive for hepatitis C antibody or hepatitis B at screening NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.