With the development and application of biological agents, the treatment effect was considerable degree improvement on refractory corn's disease. However, there are quite a part of the CD patients lost response during treatment of using response. Moreover, due to various reasons, there still a lot limited on the using of biological agents in China, that make quite a part of the refractory CD patients lack of further medical treatment options. There has been a RCT study which prove that thalidomide effect and safety on treating refractory CD or who were lost response by using biological agents in Italy, but the object of study is only limited in children and adolescents. There are some small sample studies also confirmed the efficacy and safety on refractory corn's disease by using thalidomide, but need more RCT evidence.

It will be divided two groups of patients by using randomized, double-blind. One group was treated by thalidomide, the other was placebo. It will be unlocked blind and analysis the effect and safety about thalidomide after 8 weeks. The second, patients still use thalidomide after unlock blind to prove its longtime treatment effect and safety.

Inclusion Criteria:

• Age 18-50 years old
• Diagnosis of patients with CD
• Disease in the activity: CDA Ⅰ > 150 points, endoscopic see active lesions
• Refractory: immunosuppressive drugs or biological agents which are used in current treatment is invalid and/or intolerance

Exclusion Criteria:

• Fiber stenosis caused by gastrointestinal obstruction symptoms
• Fistula exclude anal fistula
• Pregnancy or lactation
• Period of women have fertility program during the study
• Treatment not foot eight weeks after last IFX
• Central or peripheral nerve disease
• Abnormal in liver and renal function
• Heart function failure
• Malignant tumor
• Active tuberculosis