BACKGROUND: Maintaining of remission early in the disease course of Crohn's disease (CD) is essential and has major impact on the future prognosis. This study aimed to identify baseline predictors to develop model allowing stratification of patients who will not benefit from long-term azathioprine (AZA) treatment and will require more intensive therapy. METHODS: This study was designed to develop clinical prediction rule using retrospective data analysis of pediatric CD patients included in prospective inception cohort. Clinical relapse was defined as necessity of re-induction of remission. Sequence of Cox models was fitted to predict risk of relapse. RESULTS: Out of 1190 CD patients from 13 European centers, 441 were included, 50.3% patients did not experience clinical relapse within 2 years of AZA treatment initiation. Median time to relapse was 2.11 (CI 1.59-2.46) years. Of all the tested parameters available at diagnosis, six were significant in multivariate analyses: C-reactive protein (p = 0.038), body mass index Z-score >0.8 SD (p = 0.002), abnormal sigmoid imaging (p = 0.039), abnormal esophageal endoscopy (p = 0.005), ileocolonic localization (p = 0.023), AZA dose in specific age category (p = 0.031). CONCLUSIONS: Although the possibility of predicting relapse on AZA treatment appears limited, we developed predictive model based on six baseline parameters potentially helpful in clinical decision. IMPACT: The possibility of predicting relapse on AZA treatment appears to be possible but limited. We identified six independent predictors available at diagnosis of early AZA/6-MP treatment failure in pediatric CD patients. Using combination of these factors, a model applicable to clinical practice was created. A web-based tool, allowing estimation of individual relapse risk in pediatric CD patients on a particular therapeutic regimen, has been developed.

• MeSH
• Azathioprine therapeutic use   adverse effects   MeSH
• Crohn Disease * complications   diagnosis   drug therapy   MeSH
• Child MeSH
• Immunosuppressive Agents therapeutic use   adverse effects   MeSH
• Remission Induction MeSH
• Humans MeSH
• Prospective Studies MeSH
• Recurrence MeSH
• Retrospective Studies MeSH
• Check Tag
• Child MeSH
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Azathioprine MeSH
• Immunosuppressive Agents MeSH

INTRODUCTION: Two antitumor necrosis factor therapies (infliximab [IFX] and adalimumab [ADA]) have been approved for the treatment of pediatric Crohn's disease (CD) but have not been compared in head-to-head trials. The aim of this study was to compare the efficacy and safety of ADA and IFX by propensity score matching in a prospective cohort of pediatric patients with luminal CD and at least a 24-month follow-up. METHODS: Among 100 patients, 75 met the inclusion criteria, and 62 were matched by propensity score. We evaluated time to treatment escalation as the primary outcome and primary nonresponse, predictors of treatment escalation and relapse, serious adverse events, pharmacokinetics, and effect of concomitant immunomodulators as secondary outcomes. RESULTS: There was no difference between ADA and IFX in time to treatment escalation (HR = 0.63 [95% CI 0.31-1.28] P = 0.20), primary nonresponse (P = 0.95), or serious adverse events. The median (interquartile range) trough levels at the primary outcome were 14.05 (10.88-15.40) and 6.15 (2.08-6.58) µg/mL in the ADA and IFX groups, respectively. On a multivariate analysis, the combination of anti-Saccharomyces cerevisiae antibody negativity and antineutrophil cytoplasmic antibody positivity was a strong independent predictor of treatment escalation (HR 5.19, [95% CI 2.41-11.18], P < 0.0001). The simple endoscopic score for CD, L3 disease phenotype, and use of concomitant immunomodulators for at least the first 6 months revealed a trend toward significance on a univariate analysis. DISCUSSION: Propensity score matching did not reveal substantial differences in efficacy or safety between ADA and IFX. The anti-S. cerevisiae antibody negativity and antineutrophil cytoplasmic antibody positivity combination is a strong predictor of treatment escalation.

• MeSH
• Adalimumab adverse effects   MeSH
• Crohn Disease * diagnosis   drug therapy   MeSH
• Child MeSH
• Immunologic Factors MeSH
• Infliximab therapeutic use   MeSH
• Humans MeSH
• Prospective Studies MeSH
• Antibodies, Antineutrophil Cytoplasmic MeSH
• Propensity Score MeSH
• Treatment Outcome MeSH
• Check Tag
• Child MeSH
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Adalimumab MeSH
• Immunologic Factors MeSH
• Infliximab MeSH
• Antibodies, Antineutrophil Cytoplasmic MeSH