Rheumatoid arthritis (RA) is a common disease with approximately 1% prevalence. RA is also a chronic, progressive disease with no cure. Current treatment goals are to minimize pain, limit joint damage, and prevent loss of function. Drugs used to treat RA include non-steroidal anti-inflammatory drugs (NSAIDS), glucocorticoids, and disease-modifying anti-rheumatic drugs (DMARDs), including biologics. Methotrexate (MTX) is the DMARD of choice in the treatment of RA, because it has been shown to be both well-tolerated and effective in achieving clinical response and slowing radiographic progression of disease. However, this drug alone results in remissions in only a small subset of patients and reliable predictors of DMARD response have yet to be identified. This study is open-label of 16-weeks duration to identify factors that help predict clinical responses to disease-modifying antirheumatic drugs (DMARD) therapies for rheumatoid arthritis (RA) participants. All participants will receive a starting dose of DMARD medication(s) which may be adjusted by the investigator as needed. If a participant becomes intolerant of a DMARD medication, the participant will be withdrawn at the discretion of the investigator. Necessary withdrawals prior to week 16 visits will be considered end of study. Otherwise, end of study data as well as study serum will be collected at week 16. A portion of the blood collected at baseline, week 8 and week 16 for the optional addendum portion of the study is for future research and will be utilized attempting to look to detect the generation of superoxide radicals. These radicals have been shown to be associated with inflammation and may correlate with the progression of RA, which if confirmed, should decrease the levels of these radicals signaling response to treatment.