A Study to Evaluate Efficacy and Safety of Infliximab in Participant With Moderate-to-Severe Refractory Intestinal Behcet's Disease

The purpose of this study is to evaluate the efficacy of infliximab in induction regimen by assessing the mean decrease in Disease Activity Index for intestinal Behcet's disease (DAIBD) score of 20 or more in participants with active intestinal Behcet's disease who are refractory to conventional therapies.

This is an open-label (all participants know the identity of the intervention), single arm, multicenter (when more than one hospital or medical school team work on a medical research study) study of Infliximab in participant with Moderate-to-Severe Refractory Intestinal Behcet's Disease. The study consists of 3 Phases: Screening Phase (4 weeks), induction Phase for 8 weeks, and maintenance Phase for 24 weeks extending from Week 0 (baseline), and a safety Follow up visit (Week 36 or approximately 6 weeks after the last administration of study drug). The duration of participation in the study for each participant is approximately 40 weeks. The mean decrease in Disease Activity Index for intestinal Behcet's disease (DAIBD) score of 20 or more will be evaluated primarily. Participants' safety will be monitored throughout the study.

Eligibility Criteria:
Inclusion Criteria:

* Participant had diagnosed of definite or probable intestinal Behcet's Disease (BD) prior to Screening
* Participant must have active intestinal BD, defined as; a) A baseline Disease Activity Index for intestinal Behcet's disease (DAIBD) score of greater than or equal to (\>=) 40; b) Endoscopy with evidence of active intestinal BD (defined as ulcerations in the ileum and/or colon). The endoscopy must have occurred within 3 months prior to baseline
* Must either be currently receiving treatment with, or have a history of having failed to respond to, or tolerate, at least 1 of the following therapies as assessed by treating physician: oral corticosteroids, 6-mercaptopurine (6-MP), azathioprine (AZA), or methotrexate (MTX). a) Have no response to oral corticosteroids within the preceding 18 months; b) Have no response to 6-MP, AZA or MTX within the preceding 5 years
* Prior to the baseline, the following conditions must be met: a) If receiving 6-MP, AZA, or MTX must have been receiving it for at least 12 weeks, and the dose must be stable for at least 4 weeks; b) If 6-MP, AZA, or MTX have been recently discontinued, they must have been stopped for at least 4 weeks; c) If receiving oral 5-aminosalicylate (5-ASA) compounds or oral corticosteroids, the dose must have been stable for at least 2 weeks; d) If oral 5-ASA compounds or oral corticosteroids have been recently discontinued, they must have been stopped for at least 2 weeks; e) If receiving cyclosporine, the dose must have been stable for at least 6 weeks; f) If cyclosporine have been recently discontinued, they must have been stopped for at least 6 weeks
* Participant must be medically stable on the basis of physical examination, medical history, vital signs and 12-lead electrocardiogram (ECG) performed at Screening. If there are abnormalities, they must be consistent with the underlying illness in the study population, or the participant may be included only if the investigator judge the abnormalities from normal to be not clinically significant or to be appropriate. This determination must be recorded in the participant's source documents by the investigator

Exclusion Criteria:

* Participant has complications of intestinal BD such as symptomatic strictures or stenoses, short gut syndrome, central nervous system or vascular manifestation, or any other manifestation that might be anticipated to require surgery, could preclude the use of the DAIBD to assess response to therapy, or would possibly confound the ability to assess the effect of treatment with infliximab
* Participant currently has or is suspected to have an abscess. Recent cutaneous and perianal abscesses are not exclusionary if drained and adequately treated at least 3 weeks prior to baseline, or 8 weeks prior to baseline for intra-abdominal abscesses, provided that there is no anticipated need for any further surgery. Participants with active fistulas may be included if there is no anticipation of a need for surgery and there are currently no abscesses identified
* Participant has had any kind of bowel resection within 6 months or any other intra-abdominal surgery within 3 months prior to baseline
* Participant has a draining (ie, functioning) stoma or ostomy
* Participant has received any of the following prescribed medications or therapies within the specified period: a) Intravenous (IV) corticosteroids within 3 weeks prior to baseline; b) Other oral immunomodulatory agents (eg, 6-thioguanine (6-TG), tacrolimus, sirolimus, or mycophenolate mofetil) within 6 weeks prior to baseline; c) Non-biologic experimental or investigational agents within 4 weeks or within 5 half-lives of agent prior to baseline, whichever is longer; d) Other immunomodulatory biologic agents within 12 weeks or within 5 half-lives of agent prior to baseline, whichever is longer; e) Treatment with apheresis (eg, Adacolumn apheresis) or total parenteral nutrition (TPN) as a treatment for intestinal BD within 3 weeks prior to baseline