The investigators designed a single center, open-label, prospective study. Adults with active idiopathic inflammatory myopathies will be enrolled, meeting the Bohan & Peter Dermatomyositis/Polymyositis(DM/PM) or Rheumatology(ACR) & European allance of associations for rheumatology(EULAR)(2017) diagnostic criteria. Inhibitors of janus kinase including tofacitinib 5 mg once a day or twice a day and baricitinib 2mg once a day or 4mg once a day was administered for 6 months to explore its efficacy and safety, which could help to evaluate inhibitors of janus kinase's clinical characteristics and mechanism. Patients would be evaluated the improvement of clinical and laboratory indexes. Changes of symptoms, immune cell subsets and cytokines were monitored. Symptoms were evaluated by Visual Analogue Scale (VAS) of patient global and physician global, manual muscle testing(MMT-8), the Health Assessment Questionnaire(HAQ), Creatine kinase, Myositis Disease Activity Assessment Tool(MDAAT).
This study aims to explore the clinical characteristics and mechanism of inhibitors of janus kinase in the treatment of idiopathic inflammatory myopathies