This study is intended to evaluate the safety and efficacy of Iguratimod in patients with active Rheumatoid Arthritis.

This is a multi-center, open, single arm study.

Inclusion Criteria:

• Subjects with a diagnosis of RA
• Subjects who have active RA at the time of screening
• Subjects who haven't used any antirheumatic drugs or have used antirheumatic drugs for more than 3 months at the time of screening
• Written informed consent

Exclusion Criteria:

• Subjects with serious cardiovascular, renal, hematologic or endocrine diseases
• Pregnant or lactating women
• ALT>1.5×ULN, AST>1.5×ULN, Cr>135umol/L
• WBC<4×109/L，HGB<85g/L，PLT<100×109/L
• Subjects with uncontrolled infection
• Patients with active gastrointestinal diseases (such as gastric ulcer, etc.)
• Allergic to any of the study drugs
• History of alcoholism
• Subjects receiving live vaccines within 3 months prior to study entry
• Subjects participating in other clinical study within 3 months prior to study entry