Efficacy and Safety Study of Tripterygium Glycoside in the Treatment of Crohn's Disease for Induction Remission

Inclusion Criteria: * Subjects should have a definitive diagnosis of Crohn's disease, based on WHO criteria. * Males and females ≥ 18 years old, including women who are not pregnant or lactating at the time of enrollment. * Subjects should have a CDAI score between 150 to 270 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). * Orally administered corticosteroids within 3 weeks before enrollment, Inhaled or dermatologic preparations for the treatment of other diseases are acceptable. * Used of infliximab or immunosuppressant within 2 months before enrollment. * Previous use of prescription doses of NSAIDs without efficacy. * Treatment with narcotic pain medications(Anti-diarrheal agents such as loperamide and diphenoxylate are permitted). * History of pancreatitis, except for subjects with a known but removed cause(such as gallstone pancreatitis). * 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). * 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 3 months.