Phase 2, Multicenter, Open-Label Extension Study With ABT-122 in Rheumatoid Arthritis Subjects Who Have Completed the Preceding M12-963 Study

- Subjects who have completed the preceding Study M12-963 (ABT-122) randomized controlled study and have not developed any discontinuation criteria, as defined in Study M12-963. * If female, subject must meet one of the following criteria: 1. Postmenopausal (defined as no menses for at least 1 year). 2. Surgically sterile (bilateral tubal ligation, bilateral oophorectomy or hysterectomy). 3. Practicing appropriate birth control, from the time of enrollment in this study until at least 150 days after the last dose of study drug. * Male who agrees to follow one of the protocol-specified pregnancy avoidance measures, including refraining from donating sperm, for up to 150 days post last dose of study drug. * Subjects must voluntarily sign and date an informed consent, approved by an Independent Ethics Committee (IEC)/Institutional Review Board (IRB), prior to the initiation of any screening or study-specific procedures. * Subject is judged to be in good health as determined by the Investigator based on the results of medical history, physical examination and laboratory profile performed.

- Pregnant or breastfeeding female. * Ongoing infections at Day 1 (Week 0) that have NOT been successfully treated within 14 days. * Anticipated requirement or receipt of any live vaccine during study participation including up to 120 days after the last dose of study drug. * Current enrollment in another investigational study; with the exception of Study M12-963, which is required. * Consideration by the Investigator, for any reason, that the subject is an unsuitable candidate to receive ABT-122.