2023 Volume 35 Issue 3 Pages 122-130
To date, 5 JAK inhibitors are available in Japan, and post-marketing surveillance（all cases）during 6-month observation has been completed and reported for tofacitinib and baricitinib. Because the major infections often occur within a relatively short period after initiation, Japanese evidence regarding infections has been established for these two drugs. As a result, when used in accordance with the guide or instructions provided by the Japanese Society of Rheumatology, the frequency of serious infections does not increase compared to biological antirheumatic drugs, but the development of herpes zoster is frequent. Elderly patients, use of glucocorticoids, and a history of herpes zoster infection have been suggested as risk factors for herpes zoster development. In serious infections, it is also necessary to pay attention to the lymphocyte count. Rheumatologists should keep such risk factors in mind. In addition, if glucocorticoids are being used, they should be reduced to the minimal dose and then discontinued. Also, administration of pneumococcal and/or shingles vaccines is strongly recommended. To reduce the severity and frequency of infectious diseases, selecting appropriate patients for JAK inhibitors is most important.
