Inclusion:Moderate to severe Crohn’s disease- CDAI 220 to 450- CRP ≥ 5 mg/L, or- Faecal calprotectin > 250 μg/g, or- SES-CD of 2 to 3- Insufficient response/intolerance to prednisolone (≥ 40 mg/d for 2 w (or equivalent) or immunomodulatorsExclusion:- Penetrating disease or fibrotic stenosis- Surgery within 6 m of screening- Anti-TNFα therapy in preceding 8 w. This evidence concerns the gene TNF and Crohn disease.