Randomized, Double-blind, Placebo-controlled Study in Patients With Fistulizing Crohn's Disease

Inclusion Criteria: * Diagnosis of Crohn' Disease * Single or multiple enterocutaneous abdominal and/or perianal and/or rectovaginal fistulas of at least 3 months'duration. * TNF-blocker naive patients or patients who are primary or secondary anti-TNF non-responders Exclusion Criteria: * CDAI greater than 450 * ongoing treatment with TNF-blockers (duration of wash-out prior to randomization is 8 weeks) * Active abscess formation within fistula * Abdominal or anorectal surgery within the last 4 weeks prior to randomization * Known immunosuppression * Infections, sepsis * Positive Test for hepatitis B or C and HIV * Patients who had life vaccination within 6 weeks prior first study drug administration, or will require live vaccination during the course of the trial * Active liver disease with ALT and/or AST greater than 3x upper limit of normal * Any severe, progressive or uncontrolled medical condition that in judgment of investigator prevents the patient from participating in the study. * History or evidence of drug or alcohol abuse within the 6 months prior first study drug administration * Pregnant or nursing women, where pregnancy is defined as the state of a female after conception and until the termination of gestation, confirmed by a positive B-hCG laboratory test