DMARDs therapy must not be used for at least 28 days prior to baseline;
If a patient has received NSAIDs，current NSAIDs therapy must have been at a stable dose for at least 28 days prior to baseline;
Patient or patient's legal representative able to give written informed consent for participation in the trial.
You may not be if
Acute or chronic infection, or history of active tuberculosis;
History of diseases of central nervous system, cardiovascular system, kidney, liver ( specified liver function index), digestive system, respiratory system , metabolism system;
Patients who have a high risk of infection (with a current infectious disease, a chronic infectious disease, a history of serious infectious disease);
Patients who use 5 Unit doses tuberculin skin test are positive( 48-72 hour scleroma reading≥5mm);
Patients who currently have, or who have a history of, malignancy;
Patients who lack of understanding ,communication or collaboration, and can't comply with the protocols;
Female patients who are breastfeeding or pregnant, who are of childbearing potential.
