Phase IV||Design : Prospective, open-label, randomized three-arms study||Main Inclusion criteria Luminal Crohn's disease patients with steroid free remission for at least 6 months and a combination therapy with infliximab and anti-metabolites for at least 8 months||Primary objective To demonstrate that Infliximab scheduled maintenance with or without antimetabolites is superior to antimetabolites alone to maintain sustained steroid-free remission over 2 years, while the latter is non inferior with regards to the mean time spent in remission over the same duration||Main co-primary end points Clinical relapse rate at 2 years Mean remission duration within 2 years Study treatment Infliximab, Mercaptopurine, azathioprine, methotrexate.||Number of subjects 225 randomized patients (75 per arm)||Study duration: 3 + 2 years Enrollment: 3 years Follow-up: 2 years