Efficacy Study of T2 Versus AZA to Maintain Clinical and Endoscopic Remission in Postoperative Crohn's Disease (T2)

Inclusion Criteria:

• Subjects should have a definitive diagnosis of Crohn's disease, based on WHO criteria
• Subjects having curative resection/ileocolonic anastomosis，pathologically diagnosed as Crohn's disease
• Lesions located in ileum or ileocecal region
• Males and females ≥ 18 years old, including women who are not pregnant or lactating at the time of enrollment.
• Body weight between 40 and 100 kg, inclusive.
• Subjects should have a CDAI score <150 at week 0
• Able to swallow tablets
• Are capable of providing written informed consent and obtained at the time of enrollment
• Willing to adhere to the study visit schedule and other protocol requirements.

Exclusion Criteria:

• Bacterial,viral or other microbial infection(including HIV)
• any of the following medications taken within 12 weeks before surgery: cyclosporine, tacrolimus, sirolimus, mycophenolate mofetil, or other investigational drugs
• any of ongoing therapy for Crohn's disease with: 5-ASA compounds, steroids, immune modifiers, systemic antibiotics, and tube feeding
• Needing orally administered corticosteroids for the treatment of other diseases. Inhaled or dermatologic preparations are acceptable.
• Previous or current use of infliximab.
• current use of prescription doses or chronic/frequent use of NSAIDs
• Treatment with narcotic pain medications. (Anti-diarrheal agents such as loperamide and diphenoxylate are permitted, providing that the dose is not increased during the study period.)
• With an ileal or colonic stoma.
• History of pancreatitis, except for subjects with a known but removed cause(such as gallstone pancreatitis)
• WBC <3.0 x 109/L, hemoglobin <80 g/L, Platelets<50,000/mm3 at the time of enrollment (or within the previous 6 months, if known)
• History of abnormal liver function tests, including AST or ALT >1.5 times upper limit of normal, alkaline phosphatase >2 times upper limit of normal, total bilirubin >2.5 mg/dL at screening (or within the previous 6 months, if known)
• With short bowel syndrome (defined as requiring oral or parenteral supplemental or total nutrition to maintain stable body weight, or more than 100 cm of small bowel resected)
• History of malignancy
• Women who are pregnant or lactating at the time of enrollment, or who intend to be during the study period.
• Participation in other clinical trial within the past 6 months