 The study consists of 4 parts: screening, treatment, post-treatment, and safety follow-up. Prior to Day 1, participants were discontinued from all disease-modifying anti-rheumatic drugs DMARDs except MTX and etanercept or adalimumab. All participants who met eligibility criteria and were enrolled in the trial were randomized to receive 500 mg rituximab or placebo on Day 1 and Day 15. A subset of 18 participants was enrolled initially and followed through Week 12 for safety. The remaining 42 participants were to be enrolled after the last participant in the subset completed Week 12 and the Data Safety Monitoring Board DSMB conducted a safety review and approved enrollment of these additional participants. Participants were dosed on Day 1 and Day 15 and followed for 56 weeks, while remaining on their current dose of MTX and etanercept or adalimumab throughout the study. The primary endpoint was assessed at Week 24. 