Study was withdrawn due to delay in timelines. There were no safety concerns regarding the study or the compound in the decision to withdraw the trial.

The primary purpose of this multi-centre, double blind-study is to evaluate the clinical response of patients with moderate to severe Cohn's Disease (CD) following treatment with different doses and dose regimens of Olokizumab, relative to placebo.

Inclusion Criteria:

• Subject is male or female, 18 to 65 years of age at Screening
• Diagnosis of CD (colonic localization) confirmed (at least 12 weeks prior to Screening) by either radiological or endoscopic evidence and/or histological examination
• Colonoscopy performed prior to first study medication administration (Week 0) with evidence of active CD and presence of ulceration but with no clinical suspicion of dysplasia or malignancy (colonoscopy to be performed after informed consent has been received, and all other Screening assessments have been completed)
• Moderately to severely active CD (CDAI score: 220 to 450, inclusive) at Baseline
• Female subjects must be either postmenopausal for at least 1 year, surgically incapable of childbearing, or effectively practicing an acceptable method of contraception (either oral/ parenteral /implantable hormonal contraceptives, intrauterine device or barrier and spermicide)

Exclusion Criteria:

• Subject has a diagnosis of Ulcerative Colitis or Indeterminant Colitis as determined by the investigator
• Subject has obstructive strictures with clinical evidence of partial or complete obstruction
• Subject has an active fistula (fistula secreting spontaneously or by gentle pressure)
• Subject has a history of diverticulitis or symptomatic diverticulosis
• Subject has any prior exposure to anti-IL-6 agents (eg, Tocilizumab)
• Female subjects who are breastfeeding, pregnant, or plan to become pregnant during the study or within 24 weeks following the last dose of the study drug
• Subject has a high risk of infection (eg, subjects with leg ulcers, indwelling urinary catheter, persistent or recurrent chest infections, and subjects who are permanently bedridden or wheelchair bound)
• Subject has a concurrent malignancy or a history of malignancy. Subjects who have been successfully treated and who have remained malignancy-free for at least 5 years prior to Screening may be included