Recent guidelines for the management of Crohn's disease conclude that currently available data are insufficient to make firm recommendations on when and in whom to stop TNF-α antibody (TNF-α Ab) treatment after having obtained clinical remission. Further, the term remission is not well uniformly defined and may incorporate one or more features such as clinical remission, as assessed by CDAI, biochemical remission, endoscopical remission etc. The recently published prospective STORI study of 115 patients with luminal Crohn's disease reported that 56% of patients with Crohn's disease who had discontinued infliximab (IFX) while in clinical remission, maintained remission one year after discontinuation of therapy. Predictors of relapse included certain clinical features as well as objective biochemical and endoscopical markers of disease activity. Consistent with these data, we have recently reported that 61% of our own patients with Crohn's disease, who discontinued IFX while in complete clinical, steroid free IFX induced remission, maintained remission after one year; and half the patients were still in remission after nearly two years (median 680 days [412-948]).~A prospective randomized study of patients with Crohn's disease is necessary to confirm and extend the limited findings above, and assess whether IFX can be safely discontinued in a selected subgroup of patients with complete clinical, biochemical, and endoscopical remission.~Methods:~Study design: Prospective, double-blinded, randomized, placebo-controlled, Danish multi-center study with estimated seven Danish participating centers. Patients and treating physicians are blinded for the type of intervention.~Study population: Patients with luminal Crohn's disease in sustained complete remission on IFX.~Study treatment: Patients are randomized to either continue IFX treatment at an unchanged dosage and frequency, or alternatively to receive matching placebo. All patients will be graded for disease activity (Crohn's Disease Activity Index (CDAI), biochemical parameters, endoscopy, and/or MRI). Following screening and inclusion patients are seen after four weeks, and then every eight weeks. Endpoints are assessed at 48 weeks.~Investigators will, as explorative analyses, examine the clinical utility of measuring IFX levels and antibodies against IFX in patients with complete remission, in order to investigate whether pharmacoimmunological data can predict the clinical outcome and rationalize therapeutic management of these patients with respect to continuation or discontinuation of IFX therapy. Additional, investigators will investigate the optimal time-point out of three to measure this activity. Patients will on the day of infusion have three blood samples drawn: one just before infusion (trough), one right after the infusion (obtained from the other arm)(peak) and one an hour after infusion (C1). Samples will be measured by common solid - and fluid phase assays for this purpose, e.g. Reporter Gene Assay (RGA).
The purpose of this study is to determine whether infliximab can favourably and safely be discontinued in patients with Crohn's disease in sustained complete clinical, biochemical, and endoscopic remission on infliximab.~Further to examine the clinical utility of measuring levels/activity of infliximab and activity of anti-infliximab Ab in patients in sustained complete remission, in order to investigate whether pharmacoimmunological data can predict the clinical outcome and rationalize therapeutic management of these patients with respect to continuation or discontinuation of infliximab therapy. Additional, to investigate the optimal time-point, out of three, to measure this activity.