Baricitinib for Refractory Takayasu Arteritis

Inclusion Criteria: * Male or female aged 18-70 years at time of screening. * Diagnosis of Takayasu arteritis (according to the 2022 ACR/EULAR) for ≥3 months before screening. * Active Takayasu arteritis at time of screening (NIH score≥2). * Resistant to traditional therapies and anti-TNF-α therapy for at least 12 months. * Given their written informed consent to participate in the trial and expected to be able to adhere to the study visit schedule and other protocol requirements. Exclusion Criteria: * TKA-related active major organ involvement requiring immunosuppressive therapy, e.g., pulmonary (e.g., pulmonary artery aneurysm), vascular (e.g., thrombophlebitis, recurrent malignant aneurysms), gastrointestinal (e.g., gastrointestinal ulcers), and central nervous system (e.g., meningoencephalitis). * High-dose glucocorticoid (\>1mg/kg/d) usage within 1 month. * Severe comorbidities: including heart failure (≥ grade III NYHA), renal insufficiency (creatinine clearance ≤30 ml/min), hepatic insufficiency (serum ALT or AST \>3 times the ULN, or total bilirubin \>ULN for the central laboratory conducting the test). Other severe, progressive or uncontrolled hematologic, gastrointestinal, endocrine, pulmonary, cardiac, neurologic, or cerebral disease (including demyelinating diseases such as multiple sclerosis). * Known allergies, hypersensitivity, or intolerance to Baricitinib or its excipients. * Had a severe infection (including, but not limited to hepatitis, pneumonia, sepsis, or pyelonephritis); had been hospitalized for an infection; or had been treated with IV antibiotics for an infection, within 2 months prior to the first administration of study agent. * Chest radiograph within 3 months prior to the first administration of study agent that showed an abnormality suggestive of a malignancy or current active infection, including tuberculosis. * Infected with HIV (positive serology for HIV antibody) or hepatitis C (positive serology for Hep C antibody). If seropositive, consultation with a physician with expertise in the treatment of HIV or hepatitis C virus infection was recommended. * Infected with hepatitis B virus. For patients who were not eligible for this study due to hepatitis B virus test results, consultation with a physician with expertise in the treatment of hepatitis B virus infection was recommended. * Had any known malignancy or has a history of malignancy within the previous 5 years (with the exception of a nonmelanoma skin cancer that had been treated with no evidence of recurrence for ≥3 months before the first study agent administration or cervical neoplasia with surgical cure). * Had uncontrolled psychiatric or emotional disorder, including a history of drug and alcohol abuse within the past 3 years that might prevent the successful completion of the study. * Received, or was expected to receive, any live virus or bacterial vaccination within 3 months before the first administration of study agent, during the study, or within 4 months after the last administration of study agent. Had a BCG vaccination within 12 months of screening. * Pregnancy, lactation or women of child-bearing potential (WCBP) unwilling to use medically approved contraception whilst receiving treatment and for 12 months after treatment has finished. * Men whose partners are of child-bearing potential but who are unwilling to use appropriate medically approved contraception whilst receiving treatment and for 12 months after treatment has finished.