A Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Efficacy of ABBV-3373 in Participants With Moderate to Severe Rheumatoid Arthritis (RA)

This study consists of a 12-week double-blind active-controlled phase and a 12 week double-blind extension period. In the active-controlled period of the first 12 weeks of treatment, participants are randomized to receive either ABBV-3373 100 mg intravenously (IV) every other week (EOW) or adalimumab 80 mg subcutaneously (SC) EOW according to a 2:1 ratio. At Week 12, the administration of ABBV-3373 was to stop to assess the durability of the observed clinical effects up to 24 weeks. Participants randomized to ABBV-3373 were to receive placebo injections, whereas participants randomized into the adalimumab arm were to continue their 80 mg dosing.