Clinical trials have shown baricitinib once daily to be effective in patients with RA. However, this Janus kinase (JAK) 1/JAK2 inhibitor has not been evaluated in a Japanese population. In this 12-week, placebo-controlled study, 145 Japanese patients were enrolled and received placebo, 1 mg, 2 mg, 4 mg or 8 mg oral baricitinib daily. Efficacy results were encouraging and consistent with earlier trials. Significantly more baricitinib patients achieved ACR20 response at Week 12 of treatment compar...