Prediction of thiopurine failure in pediatric Crohn's disease: pediatric IBD Porto group of ESPGHAN

ECCO Topical Review on Predictive Models on Inflammatory Bowel Disease Disease Course and Treatment Response

BACKGROUND AND AIMS

Inflammatory bowel disease (IBD) poses a clinical challenge due to its variable progression and treatment response. Despite the development of predictive models, their clinical application remains limited due to validation and methodological inconsistencies. The current topical review examines existing predictive models, assesses their relevance, and discusses the barriers to their clinical implementation.

METHODS

An expert panel formed by European Crohn's and Colitis Organisation, including gastroenterologists, surgeons, and clinical epidemiologists, reviewed predictive models on IBD disease course and treatment response. Delphi methodology was applied to develop practice position statements. A practice position was set when at least 80% of participants reached agreement on a recommendation.

RESULTS

Fourteen practice positions and 2 perspective points were developed, highlighting factors included in models predicting IBD disease course and treatment response identified in the literature and barriers to clinical implementation. The appropriate methodological approaches for model development and validation have been defined, while methodological barriers to tackle have been identified. Perspectives on the inclusion of relevant biomarkers, and flexible study design have been outlined.

CONCLUSIONS

This topical review offers practice recommendations and guidance for future predictive models on IBD disease course and treatment response including their implementation in clinical practice.

Preventing Recurrence of Crohn's Disease Post-Ileocaecal Surgery in Paediatric Patients: A Therapy Guide Based on Systematic Review of the Evidence

BACKGROUND AND AIMS

Ileocaecal resection (ICR) is frequent in paediatric patients with Crohn's disease (pCD). Despite rates of reoperation being low, the risk of clinical or endoscopic post-operative recurrence (POR) is high; effective medical strategies to prevent POR are thus needed. The aim of this systematic review (SR) was to identify and evaluate the published literature on post-operative medical prevention of POR in pCD to draft a possible therapy guide for pCD patients undergoing ICR.

METHODS

We performed an SR according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards and registered it in the PROSPERO database (ID: CRD42024533855). The population, intervention, control, outcome (PICO) model was focussed on post-surgical medical prevention of POR in pCD with clearly expressed definition of recurrence (endoscopically using a standardized scoring system (e.g. Rutgeerts score) or by laboratory markers, for example, faecal calprotectin (F-CPT), C-reactive protein (CRP) or by histological findings or by clinical activity indexes [e.g. weighted paediatric Crohn's disease activity index - (w)PCDAI]. From inception until 29 February 2024, the following databases were searched: PubMed/MEDLINE, Scopus/Embase, Web of Sciences, Evidence-Based Medicine Reviews (including Cochrane), Cochrane Central Registrar of controlled Trials (CENTRAL), ClinicalTrials.gov and EudraCT. Retrieved articles were evaluated for eligibility and finally selected publications for risk of bias using ROBINS-I tool.

RESULTS

Out of 811 publications identified by the search, only 5 fulfilled inclusion criteria of the SR. None of the studies fully answered our PICO question. The studies were overall of poor quality and the heterogeneity of the data did not allow us to perform meta-analysis, detailed statistical analysis or formal synthesis of data. Adverse events of post-operative medication were not described in any of the included studies. Existing guidelines of European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN), North American Society for Paediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN), European Crohn's and Colitis Organisation (ECCO) and American Gastroenterological Association (AGA) were reviewed and paediatric therapy guide for pCD undergoing ICR was drafted with respect to recent SRs and meta-analyses in adult population and including scarce paediatric data identified by our SR. As pCD patients undergoing ICR are a high-risk population, they should not be left untreated post-operatively. Anti-tumour necrosis factor (anti-TNF) drugs should be considered as first-line therapy in the majority of patients. Non-anti-TNF biologics should be considered in case of anti-TNF failure. Regular endoscopic monitoring starting at 6 months after the surgery and supported by regular F-CPT evaluation should be used to identify early endoscopic recurrence and to escalate the treatment.

CONCLUSION

Our SR revealed that there is wide variability in treatment strategies in children, and high-quality data are generally lacking. At the moment, paediatric prophylaxis of POR should be guided by available adult evidence with respect to the high-risk nature of pCD. Extensive research in pCD should be encouraged.

Sustainability of biologic treatment in paediatric patients with Crohn's disease: population-based registry analysis

BACKGROUND

We aimed to evaluate the predictors of sustainability of biologic drugs for paediatric patients with Crohn's disease (CD).

METHODS

The Czech National Prospective Registry of Biologic and Targeted Therapy of Inflammatory Bowel Disease (CREdIT) was used to identify the biologic treatment courses in paediatric patients with CD. Mixed-effects Cox models and propensity score analyses were employed to evaluate predictors of treatment sustainability.

RESULTS

Among the 558 observations of 473 patients, 264 were treated with adalimumab (47%), 240 with infliximab (43%), 41 with ustekinumab (7%), and 13 with vedolizumab (2%). Multivariable analysis revealed higher discontinuation risk with infliximab compared to adalimumab (HR = 0.600, 95%CI 0.389-0.926), both overall and in first-line treatment (HR = 0.302, 95%CI 0.103-0.890). Infliximab versus adalimumab was associated with shorter time to escalation (HR = 0.094, 95%CI 0.043-0.203). Propensity-score analysis demonstrated lower sustainability of infliximab (HR = 0.563, 95%CI 1.159-2.725). The time since diagnosis to treatment initiation (HR = 0.852, 95%CI 0.781-0.926) was the most important predictor. Baseline immunosuppressive therapy prolonged sustainability with infliximab (HR = 2.899, 95%CI 1.311-6.410).

CONCLUSIONS

Given the results suggesting shorter sustainability, the need for earlier intensification and thus higher drug exposure, and the greater need for immunosuppression with infliximab than with adalimumab, the choice of these drugs cannot be considered completely equitable.

IMPACT

Our study identified predictors of sustainability of biologic treatment in paediatric patients with Crohn's disease, including adalimumab (versus infliximab), early initiation of biologic treatment, and normalised baseline haemoglobin levels. Infliximab treatment was associated with earlier intensification, higher drug exposure, and a greater need for immunosuppression. Parents and patients should be fully informed of the disadvantages of intravenous infliximab versus adalimumab during the decision-making process. This study emphasises the importance of not delaying the initiation of biologic therapy in paediatric patients with Crohn's disease.

Thiopurines Maintenance Therapy in Children With Ulcerative Colitis: A Multicenter Retrospective Study

BACKGROUND AND AIMS

Thiopurines are an established treatment for pediatric ulcerative colitis (UC). However, data regarding safety and efficacy are lacking. We aimed to determine short and long-term outcome following thiopurines use in children with UC.

METHODS

We conducted a retrospective review of children (2-18 years) with UC treated with thiopurines between January 2008 and January 2019 at 7 medical centers in Israel. The primary outcome was corticosteroid (CS)-free clinical remission at week 52 following thiopurines initiation without the need for rescue therapy (infliximab, calcineurin inhibitors, or colectomy).

RESULTS

A total of 133 children were included [median age at diagnosis of 12.4 (interquartile range 11.0-15.8) years, 30 (23%) left-sided colitis, 113 (85%) with moderate or severe disease at diagnosis]. At diagnosis 58 patients (44%) were treated with 5-aminosalicylates and 72 (54%) with CS. Sixty patients (45%) received thiopurines as 1st line maintenance therapy. Seventy-four patients (56%) had CS-free clinical remission at week 52 without rescue therapy. Predictors of clinical remission were not identified. In a sub-analysis among patients with steroid-responsive moderate to severe UC, 59 (55%) patients achieved this outcome. The likelihood of remaining free of rescue therapy among thiopurines-treated patients was 83%, 62%, 45%, and 37% at 1, 2, 3, and 4 years, respectively.

CONCLUSION

More than half of children with UC starting thiopurines without previous or concomitant biologic therapy have CS-free clinical remission at 52 weeks later without the need for rescue therapy. Thiopurines are effective in pediatric UC and could be considered prior to biologics.