This study evaluated the cost-effectiveness of introducing tofacitinib, an oral Janus kinase inhibitor, to the treatment of Korean patients with RA and an inadequate response to conventional DMARDs. The model showed that the inclusion of tofacitinib as a treatment strategy for moderate to severe RA is cost-effective; this conclusion was considered robust based on multiple sensitivity analyses.First-line tofacitinib used before the standard of care (base-case analysis) increased both treatment c...