Tofacitinib inhibits the Janus kinases, tyrosine kinases that are activated by cytokines involved in the pathophysiology of rheumatoid arthritis. Areas covered: Clinical trials have revealed an anti-rheumatic effect of monotherapy and combination therapy with methotrexate (MTX). Post-hoc analysis of those clinical trials and real-world experiences will be reviewed to explore efficacy and safety. Expert commentary: The efficacy of tofacitinib monotherapy has garnered much attention and has been initiated in large number of patients. However, combination therapy with MTX is necessary in order to achieve the maximum effect. Combination therapy can be transferred to monotherapy by tapering and/or discontinuing MTX. The discontinuation of tofacitinib should be avoided and tapering should be investigated. There has been no new safety signal although venous thrombotic events (VTEs) have been raised and would require long-term follow-up. Increased events of Herpes zoster were observed and the use of a subunit vaccination is expected to become an effective tool for prevention. Post-hoc analysis of the clinical trials and real-world experience is revealing further usefulness of tofacitinib not only in rheumatoid arthritis but also other diseases. Additional experience and data from the real world are required to help improve the use of tofacitinib..
Keywords: Janus kinase; Tofacitinib; herpes zoster; real-world; rheumatoid arthritis; tofacitinib; venous thromboembolism.