this study is a phase 2, multi-center, randomized, placebo-controlled, double-blind, parallel-group study to evaluate Hemay005 efficacy and safety of the treatment of patients with Behçet Disease(BD). Around 252 subjects will be randomized into this study.~The whole study will including 4 phases that a screening phase, core-treatment phase(12weeks), extended-treatment phase (12weeks) and follow-up phase(4 weeks).~Screening: All subjects will undergo a screening period of up to 6 weeks prior to baseline visit (visit 2, day of randomization, Day0).~Core treatment phase: eligible BD patients will randomly assigned to Hemay005 high-dose group, Hemay005 low-dose group, placebo (core treatment phase) + Hemay005 high-dose group (extended treatment phase), or placebo (core treatment phase) + Hemay005 low-dose group (extended treatment phase). During the core-treatment period, hemay005 will be administered twice daily for 12 weeks. The randomization was stratified to minimize the imbalance between treatment groups.~Extended treatment phase: Subjects in the high-dose and low-dose groups during the extended treatment period will still given the dose of core-treatment phase for 12 weeks. Subjects who received placebo during the core treatment will assigned to either a high-dose group or a low-dose group according the allocation at visit 2 until 12 weeks after. During this period, the subject and investigator are remain blind at this stage.~Follow up phase: Subjects in the study (also including those who withdraw from treatment for any reason) will have another follow up for 4 weeks after the end of the last administration.
This is a phase 2, multi-center, randomized, placebo-controlled, double-blind, parallel-group study with an equal randomization among the Hemay005 high dose, lower dose and placebo treatment groups. After subject randomization, each subject will enter an core-treatment Phase for 12 weeks following an extended-treatment phase for another 12weeks and a follow up phase for 4weeks.