Study of Iguratimod Plus Methotrexate Compared to Leflunomid Plus Methotrexate in Patients With Rheumatoid Arthritis

A Randomized, Double-blind Study to Evaluate the Efficacy and Safety of Iguratimod or Leflunomide in Combination With Methotrexate in Patients With Active Rheumatoid Arthritis

This study is intended to evaluate the efficacy and safety of Iguratimod Plus Methotrexate Compared to Leflunomid Plus Methotrexate in patients with active Rheumatoid Arthritis (RA).

Inclusion Criteria:

• Subjects with a diagnosis of RA according to the diagnostic criteria of the American College of Rheumatology (ACR) (revised in 1987)
• Rheumatoid Arthritis for more than 3 months from the time of the initial diagnosis
• Functional Class II-III
• Subjects have active RA at the time of screening
• Subjects with inadequate response to biologics should have a washout period before the initiation of study. For etanercept, washout period should be 2-week, and 8-week for infliximab and adalimumab.
• For firstly diagnostic RA patients, the disease activity should be moderate to severe, with DAS28>3.2
• Must have at least 4 tender joints (66 join count) and 8 swollen joints( 68 join count) at screening and baseline
• Has a C-reactive protein ≥ 10 mg/L(or 1.0 mg/dL) OR Erythrocyte Sedimentation Rate (ESR) ≥ 28 mm/hr
• Must have a negative Pregnancy test and use adequate method of contraception throughout the trial
• Written informed consent

Exclusion Criteria:

• Preceding treatment with DMARDs, immunosuppressants (cyclophosphamide, cyclosporine, azathioprine, etc.), or Tripterygium within 4 weeks prior to study entry
• Subjects have been treated with iguratimod or leflunomide combined with MTX before screening.
• Subjects combined with other autoimmune disease, such as systemic lupus erythematosus (SLE), mixed connective tissue disease (MCTD), scleriasis and polymyositis, except for Sjögren syndrome.
• Chest x-ray abnormalities, such as tuberculosis, interstitial pulmonary fibrosis, etc.
• ALT >1.5×ULN, AST >1.5×ULN, Cr >135umol/L, total bilirubin>1.5×ULN
• WBC<4×109/L，HGB<85g/L，PLT<100×109/L
• Subjects with serious cardiovascular, renal, hematologic, endocrine diseases or malignant
• Women of Pregnant or breastfeeding, and male or female with recent plan to conception
• Subjects with immunodeficiency, uncontrolled infection and active gastrointestinal disease
• Allergic to any of the study drugs
• History of alcoholism
• Subjects with mental illness
• Subjects receiving live vaccines recently
• Subjects participating in other clinical study within 3 months prior to study entry