Efficacy and safety of baricitinib in Japanese patients with active rheumatoid arthritis: A 52-week, randomized, single-blind, extension study

AbstractObjectives: The objective of this study is to evaluate the efficacy and safety of long-term (64 weeks; 52-week extension of a 12-week study) baricitinibtreatment in Japanese patients with active rheumatoid arthritis (RA) despite methotrexate therapy.Methods: Patients (N = 145) with active RA were randomized to placebo, 1mg, 2mg, 4mg, or 8mg baricitinibfor the first 12 weeks. During the 52-week extension period, patients on 4mg or 8mg baricitinibremained on the same dose and all other patients were re-randomized to 4mg or 8mg baricitinib. Most patients on 8mg baricitinibwere switched to 4mg by week 64 (protocol amendment); data analysis was based on the treatment group at the beginning of the extension period.Results: Increases in the American College of Rheumatology(ACR) response rates (ACR20, ACR50, and ACR70) observed during the first 12 weeks were maintained during the extension period, accompanied by improvements in ACR core components. At week 64, a large proportion of patients (>40%) ha...