[Role of janus kinase inhibitors in the treatment of rheumatic diseases].

Janus kinases inhibitors (JAKI) are new orally administrable disease-modifying antirheumatic drugs (DMARD) for the treatment of rheumatoid arthritis (RA) and psoriatic arthritis (PsA), representing a treatment alternative equally effective as biological DMARD that is also classified equivalent in the guidelines. JAKI reversibly inhibit intracellular signal transduction from the cytokine receptor to the nucleus. Tofacitinib and baricitinib, two JAKI already approved for RA treatment, are taken once or twice a day, respectively, and two more are expected to receive approval next year. Tofacitinib is also approved for PsA. Generally, JAKI are initially used in combination with methotrexate (MTX) but are equally effective as monotherapeutic treatment if MTX is contraindicated. In terms of therapy safety, JAKI and bDMARD are generally comparable with one exception: JAKI are associated with an increased risk of herpes zoster infection. JAKI treatment requires laboratory blood tests, especially blood count, transaminases and creatinine. Due to hepatic metabolization, tofacitinib is associated with certain drug interactions. Altogether JAKI enhance treatment possibilities for diseases such as RA and PsA combining the same effectiveness and safety as bDMARD with the option of oral administration.