Long-term outcome of treatment with infliximab in pediatric-onset Crohn's disease: a population-based study

Performance of Eight Infliximab Population Pharmacokinetic Models in a Cohort of Dutch Children with Inflammatory Bowel Disease

BACKGROUND AND OBJECTIVE

Efficacy of infliximab in children with inflammatory bowel disease can be enhanced when serum concentrations are measured and further dosing is adjusted to achieve and maintain a target concentration. Use of a population pharmacokinetic model may help to predict an individual's infliximab dose requirement. The aim of this study was to evaluate the predictive performance of available infliximab population pharmacokinetic models in an independent cohort of Dutch children with inflammatory bowel disease.

METHODS

In this retrospective study, we used data of 70 children with inflammatory bowel disease (443 infliximab concentrations) to evaluate eight models that focused on infliximab pharmacokinetic models in individuals with inflammatory bowel disease, preferably aged ≤ 18 years. Predictive performance was evaluated with prior predictions (based solely on patient-specific covariates) and posterior predictions (based on covariates and infliximab trough concentrations). Model accuracy and precision were calculated with relative bias and relative root mean square error and we determined the classification accuracy at the trough concentration target of ≥ 5 mg/L.

RESULTS

The population pharmacokinetic model by Fasanmade was identified to be most appropriate for the total dataset (relative bias before/after therapeutic drug monitoring: -20.7%/11.2% and relative root mean square error before/after therapeutic drug monitoring: 84.1%/51.6%), although differences between models were small and several were deemed suitable for clinical use. For the Fasanmade model, sensitivity and specificity for maximum posterior predictions for the next infliximab trough concentration to be ≥ 5 mg/L were respectively 83.5% and 80% with an area under the receiver operating characteristic curve of 0.870.

CONCLUSIONS

In our paediatric cohort, various models provided acceptable predictive performance, with the Fasanmade model deemed most suitable for clinical use. Model-informed precision dosing can therefore be expected to help to maintain infliximab trough concentrations in the target range.

Durability of Adalimumab and Infliximab in Children With Crohn's Disease: A Nationwide Comparison From the epi-IIRN Cohort

BACKGROUND

In a nationwide cohort, we aimed to compare the durability of infliximab and adalimumab as first biologic treatment in children with Crohn's disease (CD), stratified as combotherapy or monotherapy.

METHODS

We used data from the epi-IIRN cohort that includes all patients with inflammatory bowel diseases in Israel. Durability was defined as consistent treatment without surgery or treatment escalation. All comparisons followed stringent propensity-score matching in Cox proportional hazard models.

RESULTS

Of the 3487 children diagnosed with CD since 2005, 2157 (62%) received biologics (1127 [52%] infliximab, 964 [45%] adalimumab and 52 [2%] vedolizumab as first biologic), representing a higher proportion than that among adults diagnosed during the same time period (5295 of 15 776 [34%]; P < .001). Time from diagnosis to initiation of biologic was shorter in pediatric-onset compared with adult-onset disease (median time during the last 3 years was 2.7 months [interquartile range 1.2-5.4] vs 5.2 months [2.6-8.9]; P < .001). The durability of adalimumab monotherapy after 1 and 5 years from initiation of treatment was better than infliximab monotherapy (79%/54% vs 67%/37%, respectively; n = 452 matched children; hazard ratio [HR], 1.7; 95% confidence interval [CI], 1.3-2.3; P < .001), while in those treated with combotherapy, durability was similar (94%/66% with infliximab vs 90%/54% with adalimumab; n = 100; HR, 1.7; 95% CI, 0.9-3.3; P = .1). Durability was higher in children treated with infliximab combotherapy vs infliximab monotherapy (87%/45% vs 75%/39%; n = 440; HR, 1.4; 95% CI, 1.1-1.8; P = .01). The durability of adalimumab monotherapy was similar to infliximab combotherapy (83%/53% vs 89%/56%, respectively; n = 238; HR, 0.9; 95% CI, 0.7-1.2; P = .4).

CONCLUSION

Our results support using adalimumab monotherapy as a first-line biologic in children with CD. When infliximab is used, combotherapy may be advantageous over monotherapy.

Early infliximab trough levels in paediatric IBD patients predict sustained remission

Background

Exposure-response studies have shown that higher infliximab concentrations are associated with better outcomes in inflammatory bowel disease. There is little agreement about the optimal time to measure infliximab levels in children.

Objectives

We aimed to evaluate whether trough levels at week 6 or week 14 predict sustained remission. The secondary aim was to define target trough levels at weeks 6 and 14.

Design

We used routinely collected electronic healthcare data of 70 anti-tumour necrosis factor naïve children with inflammatory bowel disease treated with a standard infliximab induction- and variable maintenance scheme.

Methods

Trough levels and blood and faecal markers for disease activity were measured before every infliximab administration. Sustained remission was defined as the absence of symptoms and low inflammatory markers between weeks 26 and 52 after the start of infliximab therapy. Optimal infliximab levels at weeks 6 and 14 were determined using the receiver operating characteristic curve.

Results

The median infliximab level at week 6 was not significantly higher in children who achieved sustained remission compared to those who did not (16.9 mg/L versus 12.0 mg/L; p = 0.058) but the median infliximab level at week 14 was significantly higher in those with sustained remission (7.7 mg/L versus 3.8 mg/L; p = 0.006). The area under the receiver operating characteristics curves at weeks 6 and 14 to predict sustained remission was 0.67 (95% CI 0.51-0.83) and 0.75 (95% CI 0.60-0.90), respectively. Target trough levels at weeks 6 and 14 were ⩾13.2 and ⩾6.9 mg/L, respectively.

Conclusion

An infliximab measurement at week 14 with a target through level ⩾6.9 mg/L best predicted sustained remission.

Long-term clinical outcomes after the discontinuation of anti-TNF agents in patients with inflammatory bowel disease: a meta-analysis

BACKGROUND

there are concerns regarding the risk of relapse after discontinuation of anti-tumor necrosis factor (anti-TNF) therapy in patients with inflammatory bowel disease (IBD). A systematic review and meta-analysis were performed to evaluate the risk of relapse after discontinuation of anti-TNF agent in patients, and the response to retreatment with the same anti-TNF agent.

METHODS

electronic databases were searched to identify relevant studies. Primary outcomes were the pooled percentage of relapses after the withdrawal of anti-TNF agents. Secondary outcomes were the pooled percentage of the response to retreatment with the same anti-TNF agent after relapse.

RESULTS

thirty-seven studies were included in this meta-analysis. The overall risk of relapse after discontinuation of anti-TNF agent was 43 % for ulcerative colitis (UC) and 43 % for Crohn's disease (CD). In UC, the relapse rate was 37 % at 1-2 year, and 58 % at 3-5 years. In CD, the relapse rate was 38 % at 1-2 year, 53 % at 3-5 years, and 49 % at more than five years. When clinical remission was the only criterion for stopping anti-TNF agent, the relapse rate was 42 % in UC and 45 % in CD, which decreased to 40 % in UC and 36 % in CD when clinical remission and endoscopic healing were required. Retreatment with the same anti-TNF agent induced remission again in 78 % of UC patients and 76 % of CD patients.

CONCLUSION

our meta-analysis showed that a high proportion of IBD patients will relapse after discontinuation of anti-TNF agent. The response to retreatment with the same anti-TNF agent is generally favorable in patients who relapse.

Current Role of Monoclonal Antibody Therapy in Pediatric IBD: A Special Focus on Therapeutic Drug Monitoring and Treat-to-Target Strategies

In the last two decades, biologicals have become essential in treating children and adolescents with inflammatory bowel disease. TNF-α inhibitors (infliximab, adalimumab and golimumab) are preferentially used. Recent studies suggest that early application of TNF-α inhibitors is beneficial to inducing disease remission and preventing complications such as development of penetrating ulcers and fistulas. However, treatment failure occurs in about one third of pediatric patients. Particularly, children and adolescents differ in drug clearance, emphasizing the importance of pharmacokinetic drug monitoring in the pediatric setting. Here, current data on the choice and effectiveness of biologicals and therapeutic drug monitoring strategies are reviewed.

Growth After Menarche in Pediatric Inflammatory Bowel Disease

OBJECTIVES

Growth impairment in pediatric patients with pediatric onset inflammatory bowel disease (IBD) is multifactorial. Reports on the effect of age at menarche on adult stature in this population are limited. This study investigated the impact of age at menarche, disease-associated factors, and mid-parental height on growth from menarche to final height (FHt) in pediatric patients with Crohn disease (CD) and ulcerative colitis (UC) and IBD unclassified (IBD-U).

METHODS

Subjects were enrolled from a prospectively maintained pediatric IBD database when IBD preceded menarche and dates of menarche and FHt measurements were recorded.

RESULTS

One hundred forty-six patients: CD 112 and UC 30/IBD-U 4. Mean age (years) at diagnosis (10.9 vs 10.1), menarche (14.4 vs 14.0), and FHt (19.6 vs 19.7). CD and UC/IBD-U patients showed significant association between Chronological age (CA) at menarche and FHt (cm, P < 0.001) but not FHt z score (FHt-Z) < -1.0 (P = 0.42). FHt-Z < -2.0 occurred in only 5 patients. Growth impairment (FHt-Z < -1.0) was associated with surgery before menarche (P = 0.03), jejunal disease (P = 0.003), low mid-parental height z score (MPH-Z) (P < 0.001), hospitalization for CD (P = 0.03) but not UC, recurrent corticosteroid, or anti-tumor necrosis factor alpha (anti-TNFα) therapy.

CONCLUSIONS

Early age of menarche was associated with greater potential for linear growth to FHt but not FHt-Z (P < 0.05). Surgery before menarche, jejunal disease, hospitalization for CD, low MPH, and weight z score were associated with FHt-Z < -1.0.

Pediatric Crohn's disease diagnosis aid via genomic analysis and machine learning

Introduction

Determination of pediatric Crohn's disease (CD) remains a major diagnostic challenge. However, the rapidly emerging field of artificial intelligence has demonstrated promise in developing diagnostic models for intractable diseases.

Methods

We propose an artificial neural network model of 8 gene markers identified by 4 classification algorithms based on Gene Expression Omnibus database for diagnostic of pediatric CD.

Results

The model achieved over 85% accuracy and area under ROC curve value in both training set and testing set for diagnosing pediatric CD. Additionally, immune infiltration analysis was performed to address why these markers can be integrated to develop a diagnostic model.

Conclusion

This study supports further clinical facilitation of precise disease diagnosis by integrating genomics and machine learning algorithms in open-access database.

Macrophages-microenvironment crosstalk in fibrostenotic inflammatory bowel disease: from basic mechanisms to clinical applications

INTRODUCTION

Intestinal fibrosis is a common complication of Inflammatory Bowel Disease (IBD) with no available drugs. The current therapeutic principle is surgical intervention as the core. Intestinal macrophages contribute to both the progression of inflammation and fibrosis. Understanding the role of macrophages in the intestinal microenvironment could bring new hope for fibrosis prevention or even reversal.

AREAS COVERED

This article reviewed the most relevant reports on macrophage in the field of intestinal fibrosis. The authors discussed current opinions about how intestinal macrophages function and interact with surrounding mediators during inflammation resolution and fibrostenotic IBD. Based on biological mechanisms findings, authors summarized related clinical trial outcomes.

EXPERT OPINION

The plasticity of intestinal macrophages allows them to undergo dramatic alterations in their phenotypes or functions when exposed to gastrointestinal environmental stimuli. They exhibit distinct metabolic characteristics, secrete various cytokines, express unique surface markers, and transmit different signals. Nevertheless, the specific mechanism through which the intestinal macrophages contribute to intestinal fibrosis remains unclear. It should further elucidate a novel therapeutic approach by targeting macrophages, especially distinct mechanisms in specific subgroups of macrophages involved in the progression of fibrogenesis in IBD.

Long-Term Follow-up and Predictors of Complicated Disease Behavior in Pediatric Crohn's Disease Patients

OBJECTIVE

Identifying predictors of inflammatory bowel disease (IBD) outcome in order to optimize individual patient management in has become an important goal. We aimed to describe the long-term outcome of pediatric Crohn disease (CD) patients and identify risk factors for complicated behavior.

METHODS

Pediatric CD patients diagnosed between 1998 and 2014, with long-term follow-up were included. Baseline data; age, gender, weight/height/BMI percentiles, and family history of IBD. Disease characteristics (Paris classification), laboratory testing, imaging and treatment were documented. Outcome data; evidence of stricturing or penetrating disease, hospitalizations, surgical intervention, malignancies, and mortality.

RESULTS

Of 93 patients included, mean age at diagnosis 13.5 (±3.2), 51 (55%) male, median follow-up 10.3 years (±4 SD(. Disease location at diagnosis: 29 (31.2%) distal ileum, 17 (18.3%) colonic, 40 (43.0%) ileo-colonic. Seven (7.5%) had upper gastrointestinal and 36 (38.7%) perianal involvement. Behavior at diagnosis, 68 (73.1%) inflammatory (B1), and 25 (26.9%) complicated [(B2 (stricturing) and/or B3 (penetrating)]. Twenty (23.2%) of B1 evolved to B2 and/or B3, thus by the end of follow-up 45 (48.4%) had complicated behavior. Sixty-seven (72%) were hospitalized, 20 (21.5%) underwent surgery, two developed malignancy with no mortalities. In a logistic regression model, growth delay (hazard ratio [HR], 5.02 [1.10-22.85], P = 0.037) and low albumin levels (HR, 3.97 [1.32-11.97], P = 0.014) at diagnosis were predictors of complicated disease in adulthood.

CONCLUSIONS

Over a quarter of pediatric Crohn disease patients present with complicated behavior. During follow-up another quarter progress to complicated disease behavior. Delayed growth and low albumin at diagnosis predict progression.

Vaccines in Children with Inflammatory Bowel Disease: Brief Review

Incidence of inflammatory bowel diseases (IBDs), including Crohn's disease (CD) and ulcerative colitis (UC), is increasing worldwide. Children with IBDs have a dysfunctional immune system and they are frequently treated with immunomodulating drugs and biological therapy, which significantly impair immune system functions and lead to an increased risk of infections. Vaccines are essential to prevent at least part of these infections and this explains why strict compliance to the immunization guidelines specifically prepared for IBD patients is strongly recommended. However, several factors might lead to insufficient immunization. In this paper, present knowledge on the use of vaccines in children with IBDs is discussed. Literature review showed that despite a lack of detailed quantification of the risk of infections in children with IBDs, these children might have infections more frequently than age-matched healthy subjects, and at least in some cases, these infections might be even more severe. Fortunately, most of these infections could be prevented when recommended schedules of immunization are carefully followed. Vaccines given to children with IBDs generally have adequate immunogenicity and safety. Attention must be paid to live attenuated vaccines that can be administered only to children without or with mild immune system function impairment. Vaccination of their caregivers is also recommended. Unfortunately, compliance to these recommendations is generally low and multidisciplinary educational programs to improve vaccination coverage must be planned, in order to protect children with IBD from vaccine-preventable diseases.

Biological therapy in pediatric age

Biological therapies, especially blocking tumor necrosis factor-α (TNFα) agents have radically changed the therapeutic approach and disease course of pediatric inflammatory bowel disease (IBD). In particular, drugs such as infliximab (IFX) and adalimumab (ADA) have been demonstrated to be effective in inducing and maintaining corticosteroid-free remission in both adult and pediatric patients with Crohns Disease (CD) and Ulcerative colitis (UC). Biosimilar biological (BioS) therapy is increasingly being used in pediatric age even though most knowledge on the safety and efficacy of these agents is based on IFX in adult IBD data. Studies show high rates of clinical response and remission in both IFX naïve patients and in patients switched from originator to BioS with similar risks of adverse events (AEs) as those reported with IFX originator. In the present review indications, efficacy and AEs of biological therapy in pediatric IBD will be discussed, as well as the role of other biological agents such as Golimumab, Vedolizumab and Ustekinumab, the role of BioS biological therapy and utility of therapeutic drug monitoring in clinical practice.

Sex-based differences in inflammatory bowel diseases: a review

Sex-based differences in inflammatory bowel disease (IBD) pathogenesis, disease course, and response to therapy have been increasingly recognized, however, not fully understood. Experimental and translational models have been leveraged to investigate hypothesized mechanisms for these observed differences, including the potential modifying role of sex hormones and sex-dependent (epi)genetic and gut microbiome changes. The primary objective of this review is to comprehensively describe sex-based differences in IBD including epidemiology, pathogenesis, phenotypic differences, therapeutic response, and outcomes.

Trough Levels of Infliximab at Week 6 Are Predictive of Remission at Week 14 in Pediatric Crohn's Disease

OBJECTIVE

Infliximab (IFX) is a frequent therapeutic option for Crohn disease (CD) patients. Early detection of responders to IFX is critical for the management of CD in order to avoid long-term exposure to the drug without benefit. This retrospective study aimed at analysing which early parameters recorded during the induction period are able to predict response to IFX during the maintenance period in pediatric CD.

PATIENTS AND METHODS

Medical records of all CD patients ages from 2 to 18 years who received IFX at a tertiary IBD center were retrospectively analyzed. Children were classified in 3 groups according to their response at week 14 (W14) remission, clinical response or , no response. The factors recorded at W0, W2, and W6, which were associated with remission at W14 were analyzed using a logistic regression.

RESULTS

Among the 111 patients included, 74.8% patients were responders to IFX at W14, including 38.7% in clinical remission and 36% with partial clinical response. Clinical remission at W14 was associated with normal growth (P < 0.01), and normal albuminemia (P = 0.01) at baseline, It was also associated with trough levels to IFX >8.3 μg/ml at week 6 (P < 0.01).

CONCLUSION

Trough levels to IFX >8.3 μg/ml at week 6 are predictive of remission at W14 for luminal disease.

Improved Population Pharmacokinetic Model for Predicting Optimized Infliximab Exposure in Pediatric Inflammatory Bowel Disease

BACKGROUND

Many pediatric patients with inflammatory bowel disease (IBD) lose response to infliximab (IFX) within the first year, and achieving a minimal target IFX trough concentration is associated with higher remission rates and longer durability. Population pharmacokinetic (PK) modeling can predict trough concentrations for individualized dosing. The object of this study was to refine a population PK model that accurately predicts individual IFX exposure during maintenance therapy using longitudinal real-practice data.

METHODS

We exported data from the electronic health records of pediatric patients with IBD treated with originator IFX at a single center between January 2011 and March 2017. Subjects were divided into discovery and validation cohorts. A population PK model was built and then validated.

RESULTS

We identified 228 pediatric patients with IBD who received IFX and had at least 1 drug concentration measured, including 135 and 93 patients in the discovery and validation cohorts, respectively. Weight, albumin, antibodies to IFX (ATI) detected by a drug-tolerant assay, and erythrocyte sedimentation rate (ESR) were identified as covariates significantly associated with IFX clearance and incorporated into the model. The model exhibited high accuracy for predicting target IFX trough concentrations with an area under the receiver operating characteristic curve (AUROC) of 0.86 (95% confidence interval [CI], 0.81-0.91) for population-based predictions without prior drug-level input. Accuracy increased further for individual-based predictions when prior drug levels were known, with an AUROC of 0.93 (95% CI, 0.90-0.97).

CONCLUSIONS

A population PK model utilizing weight, albumin, ordinal drug-tolerant ATI, and ESR accurately predicts IFX trough concentrations during maintenance therapy in real-practice pediatric patients with IBD. This model, which incorporates dynamic clinical information, could be used for individualized dosing decisions to increase response durability.

4-1BBL Regulates the Polarization of Macrophages, and Inhibition of 4-1BBL Signaling Alleviates Imiquimod-Induced Psoriasis

4-1BBL, a member of the TNF superfamily, regulates the sustained production of inflammatory cytokines in macrophages triggered by TLR signaling. In this study, we have investigated the role of 4-1BBL in macrophage metabolism and polarization and in skin inflammation using a model of imiquimod-induced psoriasis in mice. Genetic ablation or blocking of 4-1BBL signaling by Ab or 4-1BB-Fc alleviated the pathology of psoriasis by regulating the expression of inflammatory cytokines associated with macrophage activation and regulated the polarization of macrophages in vitro. We further linked this result with macrophage by finding that 4-1BBL expression during the immediate TLR response was dependent on glycolysis, mitochondrial oxidative phosphorylation, and fatty acid metabolism, whereas the late-phase 4-1BBL-mediated sustained inflammatory response was dependent on glycolysis and fatty acid synthesis. Correlating with this, administration of a fatty acid synthase inhibitor, cerulenin, also alleviated the pathology of psoriasis. We further found that 4-1BBL-mediated psoriasis development is independent of its receptor 4-1BB, as a deficiency of 4-1BB augmented the severity of psoriasis linked to a reduced regulatory T cell population and increased IL-17A expression in γδ T cells. Additionally, coblocking of 4-1BBL signaling and IL-17A activity additively ameliorated psoriasis. Taken together, 4-1BBL signaling regulates macrophage polarization and contributes to imiquimod-induced psoriasis by sustaining inflammation, providing a possible avenue for psoriasis treatment in patients.

Trends of Utilization of Tumor Necrosis Factor Antagonists in Children With Inflammatory Bowel Disease: A Canadian Population-Based Study

BACKGROUND

Population-based studies examining the prevalence of anti-tumor necrosis factor (anti-TNF) antagonist utilization in children and young adults with inflammatory bowel disease (IBD) are lacking. We aimed to describe the trend of anti-TNF utilization in pediatric IBD over time.

METHODS

Survival analyses were performed for all patients diagnosed with IBD before age 18 years in the province of Manitoba to determine the time from diagnosis to first anti-TNF prescription in different time eras (2005-2008, 2008-2012, 2012-2016).

RESULTS

There were 291 persons diagnosed with IBD (157 with Crohn's disease [CD] and 134 with ulcerative colitis [UC]) over the study period. The likelihood of being initiated on an anti-TNF by 1, 2, and 5 years postdiagnosis was 18.4%, 30.5%, and 42.6%, respectively. The proportion of persons aged <18 years utilizing anti-TNFs rose over time; in 2010, 13.0% of CD and 4.9% of UC; by 2016, 60.0% of CD and 25.5% of UC. For those diagnosed after 2012, 42.5% of CD and 28.4% of UC patients had been prescribed an anti-TNF antagonist within 12 months of IBD diagnosis. Initiating an anti-TNF without prior exposure to an immunosuppressive agent increased over time (before 2008: 0%; 2008-2012: 18.2%; 2012-2016: 42.8%; P < 0.001). There was a significant reduction in median cumulative dose of corticosteroids (CS) in the year before anti-TNF initiation (2005-2008: 4360 mg; 2008-2012: 2010 mg; 2012-2016: 1395 mg prednisone equivalents; P < 0.001).

CONCLUSIONS

Over a period of 11 years, anti-TNFs are being used earlier in the course of pediatric IBD, with a parallel reduction in the cumulative CS dose.

Predictors of Flares in Infliximab-treated Children With Inflammatory Bowel Disease

One third of pediatric IBD patients who initially respond to infliximab (IFX) lose that response over time. This retrospective study, including 62 children treated with IFX from 2004 to 2017, aimed to identify factors associated with clinical flare. Ulcerative colitis, extreme body mass index, and lowest IFX trough levels were associated with clinical flare in the whole population. In Crohn disease patients, perianal disease was pejorative, while location proximal to ligament of Treitz was protective. Underweight patients probably correspond to the most severe cases who are more likely to relapse, with hypoalbuminemia responsible for lower systemic IFX availability. Obesity probably induces higher IFX clearance.

Infections and malignancies risks related to TNF-α-blocking agents in pediatric inflammatory bowel diseases

Introduction: Tumor necrosis factor-α (TNF-α)-blocking agents are drugs approved for the treatment of inflammatory bowel diseases (IBDs). Infliximab and adalimumab are approved for the treatment of IBD in the pediatric setting with the improvement of therapeutic management. Biological agents, also in the pediatric population, can be administered either alone or in combination with immunomodulators. Their use has raised safety concerns regarding the risk of infections and malignancies.Areas covered: A broad review of the safety concerns for the use of anti-TNF-α drugs in children with IBD was performed, and information regarding the risk of infections and malignancies were updated, also in comparison with the safety of traditional drugs such as steroids and/or immunosuppressants.Expert commentary: Anti-TNF-α drugs have shown favorable safety profiles, and adalimumab treatment is associated with lower immunogenicity compared with infliximab. Heightened awareness and vigilant surveillance leading to prompt diagnosis and treatment are important for optimal management.

Long-term outcome of pediatric-onset Crohn's disease: A population-based cohort study

BACKGROUND

Pediatric-onset Crohn's disease (CD) may represent a more severe form of disease. The aim of this study was to describe long-term outcome and identify associated risk factors of complicated behavior in a large population-based pediatric-onset CD cohort.

PATIENTS AND METHODS

Cases included all patients recorded in the EPIMAD registry diagnosed with definite or probable CD between January 1988 and December 2004, under the age of 17 years at the time of diagnosis, with at least two years of follow-up.

RESULTS

Five hundred and thirty-five patients were included. Median follow-up was 11.1 years [IQR, 7.3-15.0]. At the end of follow-up, 8% (n = 44) of patients had pure ileal disease (L1), 8% (n = 44) had pure colonic disease (L2), and 83% (n = 439) had ileocolonic disease (L3). L4 disease and perianal disease were observed in 42% (n = 227) and 16% (n = 85) of patients, respectively. At the end of follow-up, 58% (n = 308) of patients presented complicated disease behavior (B2, 39% and B3, 19%), and 42% (n = 163) of patients with inflammatory behavior at diagnosis had evolved to complicated behavior. During follow-up, 86% of patients (n = 466) received at least one course of corticosteroids, 67% (n = 357) of patients had been exposed to immunosuppressants and 35% (n = 187) of patients received at least one anti-TNF agent. Forty-three percent (n = 230) of patients underwent at least one intestinal resection. The overall mortality rate was 0.93% and the SMR was 1.6 [0.5-3.8] (p = 0.20). Five cancers were reported with a crude cancer incidence rate of 1.1% and an SIR of 3.3 [1.2-7.0] (p = 0.01). In a multivariate Cox model, ileal (HR, 1.87 [1.09-3.21], p = 0.022) or ileocolonic (HR, 1.54 [1.01-2.34], p = 0.042) and perianal lesions at diagnosis (HR, 1.81 [1.13- 2.89], p = 0.013) were significantly associated with complicated behavior.

CONCLUSION

About 80% of patients with pediatric-onset CD presented extensive ileocolonic disease during follow-up. The majority of patients evolved to complicated behavior. Surgery, cancer and mortality were observed in 43%, 0.9% and 0.9% of patients, respectively.

Therapeutics for Inflammatory Bowel Diseases in Children and Adolescents: A Focus on Biologics and an Individualized Treatment Paradigm

Pharmacologic treatment of children and adolescents with inflammatory bowel diseases (IBD) [Crohn's disease and ulcerative colitis] requires consideration of disease and medication effects on growth and nutrition, the importance of durability of biologics, and concerns for long-term sequelae of disease and therapies. Achieving early remission in children with Crohn's disease correlates with improved outcomes and therefore allows a window of opportunity for maximizing growth. Thus, there is a great need to treat children and adolescents with the right drug at the right time while achieving adequate exposure. Improved understanding of disease phenotypes, disease natural history, and risk stratification will play a critical role in treatment selection for children, particularly as more therapeutic options become available. Here we summarize data supporting newer concepts of treating the individual child with IBD through targeted early biologic treatment, including utilization of therapeutic drug monitoring to optimize treatment effects and the use of early antitumor necrosis factor (TNF)-α therapies to mitigate long-term sequelae of the disease. Recent inception cohort studies provide important data regarding the risk stratification of children and adolescents with IBD, which support a move toward a personalized therapeutic approach to IBD in children and adolescents.

Early Infliximab Yields Superior Long-Term Effects on Linear Growth in Pediatric Crohn's Disease Patients

Background/Aims

Information regarding the efficacy of early infliximab treatment in pediatric patients with Crohn’s disease (CD) is limited. We aimed to evaluate the impact of early combined immunosuppression on linear growth in pediatric patients with CD by performing step-up comparisons.

Methods

This retrospective study included pediatric patients with moderate-to-severe CD, who received a combination therapy with infliximab and azathioprine for at least 3 years and sustained corticosteroid-free remission without loss of response. The z-scores of the growth indicators obtained at the time of diagnosis and annually for 3 years thereafter were compared between the two groups.

Results

The early combined immunosuppression group displayed significantly increased linear growth 3 years after diagnosis (p=0.026). A significant difference was also observed in the linear growth 3 years after diagnosis between subgroups of Tanner stages 1–2 (p=0.016).

Conclusions

The early introduction of biologics should be considered to improve linear growth in pediatric patients with CD.

Age at disease onset of inflammatory bowel disease is associated with later extraintestinal manifestations and complications

INTRODUCTION

A small but increasing number of patients with inflammatory bowel disease are diagnosed during childhood or adolescence, and disease distribution and severity at onset vary according to the age at diagnosis. Clinical factors present at the time of diagnosis can be predictive of the disease course.

AIM

The aim of this study was to characterize disease behavior and the cumulative complications and extraintestinal manifestations 10 years after the diagnosis and to assess their association with age at diagnosis.

PATIENTS AND METHODS

Data of patients participating with the Swiss IBD cohort study registry, a disease duration of 10 years and a complete data set were analyzed. The outcome was defined as the cumulative change of disease behavior, the occurrence of extra-intestinal manifestations or complications, and the necessity for medical or surgical interventions.

RESULTS

A total of 481 patients with Crohn's disease (CD) and 386 patients with ulcerative colitis (UC), grouped according to disease onset before 10, 17, 40, or after 40 years of age, were analyzed. Despite differences in sex, initial disease location, and smoking habits, at 10 years after the diagnosis, no difference was found regarding disease behavior in CD or regarding progression of disease extension in UC. Similarly, no age-of-onset-dependent cumulative need for medical or surgical therapies was found. However, higher rates of anemia and lower rates of arthralgia and osteopenia were found in both pediatric-onset CD and UC, and a tendency toward higher rates of stomatitis in pediatric-onset CD, and of primary sclerosing cholangitis and ankylosing spondylitis in pediatric-onset UC.

CONCLUSION

After 10 years of disease evolution, age at disease onset is not anymore associated with disease behavior but only with a small difference in the occurrence of specific extraintestinal manifestations and complications.

Subtherapeutic Infliximab Trough Levels and Complete Mucosal Healing Are Associated With Sustained Clinical Remission After Infliximab Cessation in Paediatric-onset Crohn's Disease Patients Treated With Combined Immunosuppressive Therapy

BACKGROUND AND AIMS

We aimed to investigate the outcome in paediatric-onset Crohn's disease patients who had discontinued infliximab after maintaining clinical remission with combined immunosuppression, and to determine factors associated with clinical relapse.

METHODS

We conducted a retrospective observational study of 63 paediatric-onset Crohn's disease patients who had stopped scheduled infliximab during sustained corticosteroid-free clinical remission for at least 1 year with infliximab and azathioprine, and were followed up for at least 1 year thereafter. Cumulative relapse rates and the median time to relapse were estimated statistically. Factors at cessation were also evaluated for their association with clinical relapse.

RESULTS

After a median follow-up period of 4.3 years [range, 1-7.5 years], 60.3% [38/63] of patients had experienced clinical relapse. According to Kaplan-Meier survival analysis, the estimated cumulative relapse rates at 1, 4, and 6 years were 19.0%, 62.2%, and 75.2%, respectively, and the median relapse time was 3.3 years from infliximab cessation. According to multivariate Cox proportional hazard regression analysis, infliximab trough levels of ≥2.5 μg/mL and incomplete mucosal healing were associated with clinical relapse (hazard ratio [HR] = 7.199, 95% confidence interval [CI] = 1.641-31.571, p = 0.009 and HR = 3.628, 95% CI = 1.608-8.185, p = 0.002, respectively). Although re-treatment with infliximab was effective in 90.9% [30/33] of patients, 7.9% [3/38] eventually underwent surgery within 1 year of relapse.

CONCLUSIONS

Considering the high cumulative relapse rates in the long term and cases of severe relapse requiring surgery, discontinuing infliximab in paediatric-onset Crohn's disease patients is currently inadvisable. However, there may be a subgroup of patients who are good candidates for infliximab withdrawal.

Withdrawal of immunosuppressant or biologic therapy for patients with quiescent Crohn's disease

BACKGROUND

Crohn's disease (CD) is a chronic, relapsing and remitting disease of the gastrointestinal tract that can cause significant morbidity and disability. Current treatment guidelines recommend early intervention with immunosuppressant or biological therapy in high-risk patients with a severe disease phenotype at presentation. The feasibility of therapeutic de-escalation once remission is achieved is a commonly encountered question in clinical practice, driven by patient and clinician concerns regarding safety, adverse events, cost and national regulations. Withdrawal of immunosuppressant and biologic drugs in patients with quiescent CD may limit adverse events and reduce healthcare costs. Alternatively, stopping these drug therapies may result in negative outcomes such as disease relapse, drug desensitization, bowel damage and need for surgery.

OBJECTIVES

To assess the feasibility and safety of discontinuing immunosuppressant or biologic drugs, administered alone or in combination, in patients with quiescent CD.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase and the Cochrane IBD Group Specialized Register from inception to 19 December 2017. We also searched the reference lists of potentially relevant manuscripts and conference proceedings to identify additional studies.

SELECTION CRITERIA

Randomized controlled trials (RCTs) and prospective cohort studies that followed patients for a minimum duration of six months after drug discontinuation were considered for inclusion. The patient population of interest was adults (> 18 years) with CD (as defined by conventional clinical, endoscopic or histologic criteria) who had achieved remission while receiving immunosuppressant or biologic drugs administered alone or in combination. Patients then discontinued the drug regimen following a period of maintenance therapy of at least six months. The comparison was usual care (i.e. continuation of the drug regimen).

DATA COLLECTION AND ANALYSIS

The primary outcome measure was the proportion of patients who relapsed following discontinuation of immunosuppressant or biologic drugs, administered alone or in combination. Secondary outcomes included: the proportion of patients who responded to the reintroduction of immunosuppressant or biologic drugs, given as monotherapy or combination therapy; the proportion of patients who required surgery following relapse; the proportion of patients who required hospitalization for CD following relapse; the proportion of patients who developed new CD-related complications (e.g. fistula, abscesses, strictures) following relapse; the proportion of patients with elevated biomarkers of inflammation (CRP, fecal calprotectin) in those who stop and those who continue therapy; the proportion of patients with anti-drug antibodies and low serum trough drug levels; time to relapse; and the proportion of patients with adverse events, serious adverse events and withdrawal due to adverse events. For dichotomous outcomes, we calculated the risk ratio (RR) and 95% confidence interval (95% CI). Data were analyzed on an intention-to-treat basis where patients with missing outcome data were assumed to have relapsed. The overall quality of the evidence supporting the primary and secondary outcomes was assessed using the GRADE criteria.

MAIN RESULTS

A total of six RCTs (326 patients) evaluating therapeutic discontinuation in patients with quiescent CD were eligible for inclusion. In four RCTs azathioprine monotherapy was discontinued, and in two RCTs azathioprine was discontinued from a combination therapy regimen consisting of azathioprine with infliximab. No studies of biologic monotherapy withdrawal were eligible for inclusion. The majority of studies received unclear or low risk of bias ratings, with the exception of three open-label RCTs, which were rated as high risk of bias for blinding. Four RCTs (215 participants) compared discontinuation to continuation of azathioprine monotherapy, while two studies (125 participants) compared discontinuation of azathioprine from a combination regimen to continuation of combination therapy. Continuation of azathioprine monotherapy was shown to be superior to withdrawal for risk of clinical relapse. Thirty-two per cent (36/111) of azathioprine withdrawal participants relapsed compared to 14% (14/104) of participants who continued with azathioprine therapy (RR 0.42, 95% CI 0.24 to 0.72, GRADE low quality evidence). However, it is uncertain if there are any between-group differences in new CD-related complications (RR 0.34, 95% CI 0.06 to 2.08, GRADE low quality evidence), adverse events (RR 0.88, 95% CI 0.67 to 1.17, GRADE low quality evidence), serious adverse events (RR 3.29, 95% CI 0.35 to 30.80, GRADE low quality evidence) or withdrawal due to adverse events (RR 2.59, 95% CI 0.35 to 19.04, GRADE low quality evidence). Common adverse events included infections, mild leukopenia, abdominal symptoms, arthralgias, headache and elevated liver enzymes. No differences between azathioprine withdrawal from combination therapy versus continuation of combination therapy were observed for clinical relapse. Among patients who continued combination therapy with azathioprine and infliximab, 48% (27/56) had a clinical relapse compared to 49% (27/55) of patients discontinued azathioprine but remained on infliximab (RR 1.02, 95% CI 0.68 to 1.52, P = 0.32; GRADE low quality evidence). The effects on adverse events (RR 1.11, 95% CI 0.44 to 2.81, GRADE low quality of evidence) or serious adverse events are uncertain (RR 1.00, 95% CI 0.21 to 4.66; GRADE very low quality of evidence). Common adverse events in the combination therapy studies included infections, liver test elevations, arthralgias and infusion reactions.

AUTHORS' CONCLUSIONS

The effects of withdrawal of immunosuppressant therapy in people with quiescent Crohn's disease are uncertain. Low quality evidence suggests that continuing azathioprine monotherapy may be superior to withdrawal for avoiding clinical relapse, while very low quality evidence suggests that there may be no difference in clinical relapse rates between discontinuing azathioprine from a combination therapy regimen, compared to continuing combination therapy. It is unclear whether withdrawal of azathioprine, initially administered alone or in combination, impacts on the development of CD-related complications, adverse events, serious adverse events or withdrawal due to adverse events. Further high-quality research is needed in this area, particularly double-blind RCTs in which biologic therapy or an immunosuppressant other than azathioprine is withdrawn.

Long-term Outcome of Early Combined Immunosuppression Versus Conventional Management in Newly Diagnosed Crohn's Disease

BACKGROUND AND AIMS

Long-term outcomes of early combined immunosuppression [top-down] compared to conventional management [step-up] in recently diagnosed Crohn's disease [CD] are unknown. We aimed to investigate long-term outcomes of participants of the Step-up/Top-down-trial.

METHODS

Trial participants' medical records were reviewed retrospectively. For 16 semesters following the 2-year trial, we recorded: clinical activity, medication use, flares, hospitalization, surgery and fistulas. Colonoscopy reports were scored as: endoscopic remission, aphthous/small ulcers or large ulcers. The primary endpoint was the proportion of semesters in remission.

RESULTS

Data were available from 119/133 patients [step-up n = 60]. During a median follow-up of 8 years, clinical remission rates were similar (70% vs 73% [p = 0.85] in step-up and top-down patients, respectively). A shorter time to flare was observed in step-up patients [median five vs nine semesters, p = 0.01]. Cumulatively, 62% of step-up patients used corticosteroids compared to 41% of top-down patients [p = 0.02]. Anti-tumour necrosis factor [anti-TNF] use was higher in the step-up group [73% vs 54%, p = 0.04]. No differences were found in to time to CD hospitalization [respectively 13 vs 14 semesters, p = 0.30], new fistula [14 vs 15 semesters, p = 0.20] or CD surgery [14 vs 15 semesters, p = 0.25]. Mucosal healing 2 years after treatment was associated with a reduced anti-TNF use, but not with differences in other long-term outcomes. Endoscopic remission occurred at similar rates between groups.

CONCLUSIONS

Top-down treatment did not result in increased clinical remission during long-term follow-up, compared to step-up treatment. However, lower relapse rates and a reduced use of anti-TNF agents and corticosteroids were observed. No difference was found in rates of endoscopic remission, hospitalization, surgery or new fistulas.

Risk of Serious Bacterial Infection Associated With Tumor Necrosis Factor-Alpha Inhibitors in Children and Young Adults With Inflammatory Bowel Disease

BACKGROUND

Prior studies evaluating the relationship between tumor necrosis factor-alpha inhibitors (TNFI) and infection were conducted in adults and had conflicting findings. We sought to examine the risk of serious infection associated with TNFIs compared with nonbiologic immunomodulators in children and young adults with inflammatory bowel disease (IBD) and to compare the risk among individual TNFIs.

METHODS

We conducted a cohort study using the Truven MarketScan Commercial Claims and Encounters database of patients age <30 years with a diagnosis of IBD who initiated treatment with a TNFI or immunomodulator (thiopurines or methotrexate) between 2009 and 2013. The outcome of interest was serious infection, defined as a nongastrointestinal bacterial infection requiring hospitalization. Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for serious infection associated with TNFIs compared with immunomodulators.

RESULTS

We identified 10,838 children and young adults with IBD; 236 and 192 cases of serious infection were observed in 4502 TNFI initiators (5.25/100 person-years) and 6336 immunomodulator initiators (3.59/100 person-years), respectively. Compared with immunomodulators, TNFIs were associated with a higher risk of serious infection (HR, 1.36; 95% CI, 1.08-1.72). Among TNFI users, certolizumab showed a 3.38-fold (95% CI, 2.25-5.09) increased risk vs infliximab, and subcutaneously administered TNFIs also exhibited a higher risk (HR, 1.34; 95% CI, 1.18-1.53) than intravenous TNFIs.

CONCLUSIONS

TNFIs pose a higher risk of serious infection compared with immunomodulators in children and young adults with IBD, and this risk differs among individual TNFIs and routes of administration.

Surgical Treatment in Childhood-onset Inflammatory Bowel Disease-A Nationwide Register-based Study of 4695 Incident Patients in Sweden 2002-2014

BACKGROUND AND AIMS

The incidence of childhood-onset [< 18 years] inflammatory bowel disease [IBD] is increasing worldwide, and some studies suggest that it represents a more severe disease phenotype. Few nationwide, population-based studies have evaluated the surgical burden in patients with childhood-onset IBD, and whether the improved medical treatment has influenced the need for gastrointestinal surgery. The aim was to examine whether the surgical treatment at any age of patients with childhood-onset IBD has changed over time.

METHODS

In a nationwide cohort study we identified 4695 children [< 18 years] diagnosed with incident IBD in 2002-2014 through the Swedish Patient Register [ulcerative colitis: n = 2295; Crohn's disease: n = 2174; inflammatory bowel disease-unclassified: n = 226]. Abdominal [intestinal resections and colectomies] and perianal surgeries were identified through the Swedish Patient Register. The cumulative incidences of surgeries were calculated using the Kaplan-Meier method.

RESULTS

In the cohort, 44% were females and 56% males. The median age at inflammatory bowel disease diagnosis was 15 years and the maximum age at end of follow-up was 31 years. The 3-year cumulative incidence of intestinal surgery was 5% in patients with ulcerative colitis and 7% in patients with Crohn's disease, and lower in children aged < 6 years at inflammatory bowel disease diagnosis [3%] than in those aged 15-17 years at diagnosis [7%]. Calendar period of inflammatory bowel disease diagnosis was not associated with risk of surgery.

CONCLUSION

Over the past 13 years, the risk of surgery in childhood-onset inflammatory bowel disease has remained unchanged.

Early Biologic Treatment in Pediatric Crohn's Disease: Catching the Therapeutic Window of Opportunity in Early Disease by Treat-to-Target

The emergence of mucosal healing as a treatment goal that could modify the natural course of Crohn's disease and the accumulating evidence showing that biologics are most effective in achieving mucosal healing, along with the success of early treatment regimens for rheumatoid arthritis, have led to the identification of early Crohn's disease and development of the concept of catching the therapeutic window during the early disease course. Thus, an increasing number of pediatric gastroenterologists are adopting an early biologic treatment strategy with or without an immunomodulator. Although early biologic treatment is effective, cost and overtreatment are issues that limit its early use. Currently, there are insufficient data on who will benefit most from early biologics, as well as on who will not need early or even any biologics. For now, top-down biologics should be considered for patients with currently known high-risk factors of poor outcomes. For other patients, close, objective monitoring and accelerating the step-up process by means of a treat-to-target approach seems the best way to catch the therapeutic window in early pediatric Crohn's disease. The individual benefits of immunomodulator addition during early biologic treatment should be weighed against its risks and decision on early combination treatment should be made after comprehensive discussion with each patient and guardian.

Short-Term Outcome of Infliximab Therapy in Pediatric Crohn's Disease: A Single-Center Experience

PURPOSE

Studies on the efficacy of infliximab (IFX) in a large population of pediatric patients with Crohn's disease (CD) are limited, and prognostic factors are not well-known. The aim of this study was to evaluate outcomes of IFX in pediatric patients with CD and to identify factors associated with poor prognosis.

METHODS

We retrospectively analyzed medical data of 594 pediatric patients with CD between 1987 and 2013 in a tertiary center. Of these, 156 children treated with IFX were enrolled and were followed up for at least a year with intact data. Outcomes of induction and maintenance, classified as failure or clinical response, were evaluated on the tenth and 54th week of IFX therapy.

RESULTS

We treated 156 pediatric patients with CD with IFX, and the median duration of IFX therapy was 47 months. For IFX induction therapy, 134 (85.9%) patients experienced clinical response on the 10th week. Among the 134 patients who showed response to induction, 111 (82.8%) patients maintained the clinical response on the 54th week. In multivariate analysis, low hematocrit (p=0.046) at the time of IFX initiation was associated with the failure of IFX induction. For IFX maintenance therapy, longer duration from the initial diagnosis to IFX therapy (p=0.017) was associated with maintenance failure on the 54th week.

CONCLUSION

We have shown the acceptable outcomes of IFX in a large cohort of pediatric CD patients in Korea. Hematocrit and early introduction of IFX may be prognostic factors for the outcomes of IFX.

Surgical care of the pediatric Crohn's disease patient

Despite the significant advances in the medical management of inflammatory bowel disease over the last decade, surgery continues to play a major role in the management of pediatric Crohn's disease (CD). While adult and pediatric Crohn's disease may share many clinical characteristics, pediatric Crohn's patients often have a more aggressive phenotype, and the operative care given by the pediatric surgeon to the newly diagnosed Crohn's patient is very different in nature to the surgical needs of adult patients after decades of disease progression. Children also have the unique surgical indication of growth failure to consider in the overall clinical decision making. While surgery is never curative in CD, it has the ability to transform the disease process in children, and appropriately timed operations may have tremendous impact on a child's physical and mental maturation. This monograph aims to address the surgical care of Crohn's disease in general, with a specific emphasis on the surgical treatment of small intestinal and ileocecal involvement.

Surgical Management of Crohn Disease in Children: Guidelines From the Paediatric IBD Porto Group of ESPGHAN

The incidence of Crohn disease (CD) has been increasing and surgery needs to be contemplated in a substantial number of cases. The relevant advent of biological treatment has changed but not eliminated the need for surgery in many patients. Despite previous publications on the indications for surgery in CD, there was a need for a comprehensive review of existing evidence on the role of elective surgery and options in pediatric patients affected with CD. We present an expert opinion and critical review of the literature to provide evidence-based guidance to manage these patients. Indications, surgical options, risk factors, and medications in pre- and perioperative period are reviewed in the light of available evidence. Risks and benefits of surgical options are addressed. An algorithm is proposed for the management of postsurgery monitoring, timing for follow-up endoscopy, and treatment options.

Prediction of complicated disease course for children newly diagnosed with Crohn's disease: a multicentre inception cohort study

BACKGROUND

Stricturing and penetrating complications account for substantial morbidity and health-care costs in paediatric and adult onset Crohn's disease. Validated models to predict risk for complications are not available, and the effect of treatment on risk is unknown.

METHODS

We did a prospective inception cohort study of paediatric patients with newly diagnosed Crohn's disease at 28 sites in the USA and Canada. Genotypes, antimicrobial serologies, ileal gene expression, and ileal, rectal, and faecal microbiota were assessed. A competing-risk model for disease complications was derived and validated in independent groups. Propensity-score matching tested the effect of anti-tumour necrosis factor α (TNFα) therapy exposure within 90 days of diagnosis on complication risk.

FINDINGS

Between Nov 1, 2008, and June 30, 2012, we enrolled 913 patients, 78 (9%) of whom experienced Crohn's disease complications. The validated competing-risk model included age, race, disease location, and antimicrobial serologies and provided a sensitivity of 66% (95% CI 51-82) and specificity of 63% (55-71), with a negative predictive value of 95% (94-97). Patients who received early anti-TNFα therapy were less likely to have penetrating complications (hazard ratio [HR] 0·30, 95% CI 0·10-0·89; p=0·0296) but not stricturing complication (1·13, 0·51-2·51; 0·76) than were those who did not receive early anti-TNFα therapy. Ruminococcus was implicated in stricturing complications and Veillonella in penetrating complications. Ileal genes controlling extracellular matrix production were upregulated at diagnosis, and this gene signature was associated with stricturing in the risk model (HR 1·70, 95% CI 1·12-2·57; p=0·0120). When this gene signature was included, the model's specificity improved to 71%.

INTERPRETATION

Our findings support the usefulness of risk stratification of paediatric patients with Crohn's disease at diagnosis, and selection of anti-TNFα therapy.

FUNDING

Crohn's and Colitis Foundation of America, Cincinnati Children's Hospital Research Foundation Digestive Health Center.

Infliximab Optimization Based on Therapeutic Drug Monitoring in Pediatric Inflammatory Bowel Disease

BACKGROUND

Infliximab (IFX) is an effective treatment for the management of moderate to severe inflammatory bowel disease (IBD). Low-serum IFX levels are associated with the development of antibodies to IFX (ATI), which subsequently associated with clinical relapse and increased morbidity. The primary purpose of this study is to examine the relation between dose and interval to IFX level. Secondary goal is to evaluate the relation between IFX level and ATI in a pediatric IBD population.

METHODS

We performed a retrospective chart review of all children diagnosed with IBD and treated with IFX at a tertiary care pediatric IBD center. We performed our analysis based on prescribed dosing intervals and rounded dose up to 5 or 10 mg/kg as indicated in clinical practice.

RESULTS

Our study included 278 samples from 129 children on IFX. ATI were detected in 37 samples (13.3%). Low IFX levels (<3 μg/mL) were detected in 37.2% of children receiving IFX. Samples with ATI present had significantly lower levels of IFX than samples in which ATI were not present. For the dose 5 mg/kg, Q6 dosing had significantly higher IFX levels than Q8 dosing (P = 0.009). Higher IFX levels were seen with interval shortening rather than dose escalation.

CONCLUSIONS

We demonstrate that low IFX levels are associated with development of immunogenicity to IFX as measured by ATI. We demonstrate that interval shortening rather than dose escalation results in higher IFX levels. We suggest that given the high number of IFX levels below 3 μg/mL in patients, early IFX level evaluation or primary initiation of Q6 week dosing be considered.

Serum-Infliximab Trough Levels in 45 Children with Inflammatory Bowel Disease on Maintenance Treatment

The role of trough serum infliximab (s-IFX) and antibodies toward IFX (ATI) during maintenance treatment remains unclear in children. The aim of the present study was to investigate trough s-IFX and ATI to identify any correlation with inflammatory activity and clinical response in a pediatric inflammatory bowel disease (IBD) cohort. We investigated the s-IFX trough levels in pediatric IBD patients (n = 45) on maintenance IFX treatment. Ninety-three blood samples were collected and demographics, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and albumin were recorded. The mean s-IFX trough level was 5.2 µg/mL. The mean trough s-IFX level was significantly higher in the samples taken during remission (7.2 µg/mL) compared to active disease (4.5 µg/mL, p < 0.05). The trough s-IFX levels correlated with ESR, CRP, and albumin. S-IFX was undetectable in eight of the patients, all with positive ATI and active disease. Surprisingly, clinical and biochemical remission was observed at only 26 of the 93 visits. The correlation between dose variations and changes in trough s-IFX was not evident. In line with studies in adults, the s-IFX trough levels correlated with response to infliximab.

The natural history of Crohn's disease in children: a review of population-based studies

The incidence of Crohn's disease (CD) has been reported to increase. The aim of this review is to perform a comprehensive literature search of population-based studies focused on the natural history of paediatric-onset CD. A literature search of English and non-English language publications listed in the electronic database of MEDLINE (source PUBMED) and EMBASE from 1935 to 2016 was performed. Population-based studies or national cohorts reporting data on the short-term or long-term disease course of paediatric CD were included. Forty-nine paediatric and 15 nonpaediatric studies on CD have been identified. Up to one-third of children with inflammatory behaviour developed bowel complications more than 5 years after diagnosis. From 48 to 88% of children have experienced at least one corticosteroid course irrespective of the period of diagnosis and up to one-third became steroid dependent. Immunosuppressive preparations were used earlier and more frequently in newer than older cohorts (68 vs. 32% at 5 years) and more than one-third of children have received biological treatment early in the disease course. A decline in the surgery rate might be observed in more recent compared with older unselected populations. The relative risk of cancer in childhood-onset CD as well as the risk of death seem to have increased. Childhood-onset CD seems to be an aggressive phenotype of the disease. Compared with older cohorts, a trend towards decreasing surgical rate can be observed in newer cohorts paralleled by an increase in immunomodulator use and biologicals. Nevertheless, the causative role has yet to be investigated.

Disease Status and Pubertal Stage Predict Improved Growth in Antitumor Necrosis Factor Therapy for Pediatric Inflammatory Bowel Disease

BACKGROUND

Growth failure is well-recognized in pediatric inflammatory bowel disease (PIBD; <18 years). We aimed to examine whether antitumor necrosis factor (TNF) therapy improves growth in a PIBD population-based cohort.

METHODS

A retrospective review of all Scottish children receiving anti-TNF (infliximab [IFX] and adalimumab [ADA]) from 2000 to 2012 was performed; height was collected at 12 months before anti-TNF (T-12), start (T0), and 12 (T+12) months after anti-TNF.

RESULTS

Ninety-three of 201 treated with IFX and 28 of 49 with ADA had satisfactory growth data; 66 had full pubertal data. Univariate analysis demonstrated early pubertal stages (Tanner 1-3 n = 44 vs T4-5 n = 22), disease remission, disease duration ≥2 years, and duration of IFX ≥12 months were associated with improved linear growth for IFX; for ADA only improvement was seen in Tanner 1-3. For IFX, Tanner 1-3 median Δ standard deviation scores for height (Ht SDS) -0.3 (-0.7, 0.2) at T0 changed to 0.04 (-0.5, 0.7) at T+12 (P < 0.001) versus -0.01 (-0.5, 0.9) at T0 in T4-5 changed to -0.01 (-0.4, 0.2) at T+12 (P > 0.05). For IFX disease duration ≥2 year, median Δ Ht SDS was -0.13 (-0.6, 0.3) at T0 then 0.07 (-0.3, 0.6) at T+12 (P < 0.001). Remission improved Δ Ht SDS (median Δ Ht SDS -0.14 [-0.6, 0.3] at T0 to 0.17 [-0.2, 0.7] at T+12 [P < 0.001]). Multiple regression analysis demonstrated corticosteroid usage at T0 predicted improved Δ Ht SDS at T+12 for IFX and ADA.

CONCLUSIONS

Anti-TNF therapy is more likely to be associated with growth improvement when used at earlier stages of puberty with remission a key growth-promoting strategy in pediatric Crohn disease.

Treatment with infliximab for pediatric Crohn's disease: Nationwide survey of Japan

BACKGROUND AND AIM

Childhood-onset inflammatory bowel disease (IBD) is characterized by extensive intestinal involvement and rapid early progression. Infliximab (IFX), cyclosporin (CYA), and tacrolimus (FK506) are increasingly used to treat pediatric IBD; however, their long-term effects and adverse events have not been properly investigated in pediatric patients. The aim of this study was to characterize the effects of these biologics and immunomodulators on pediatric IBD patients in Japan. Additionally, we assessed IFX use in pediatric patients with Crohn's disease (CD).

METHODS

A national survey of IFX, adalimumab, CYA, and FK506 use in pediatric IBD patients (< 17 years of age) was sent to 683 facilities in Japan from December 2012 to March 2013. Secondary questionnaires were sent to pediatric and adult practitioners with the aim of assessing the effectiveness and safety of IFX for pediatric CD patients.

RESULTS

The response rate for the primary survey was 61.2% (N  =  418). Among 871 pediatric CD patients, 284 (31.5%), 24, 4, and 15 received IFX (31.5%), adalimumab, CYA, and FK506, respectively, from 2000 to 2012. According to the secondary survey, extensive colitis (L3, Paris classification) was diagnosed in 69.4% of pediatric CD patients who received IFX. Regarding the effectiveness of IFX in this population, 54.7% (99/181) of patients were in remission, and 42.0% (76/181) were on maintenance therapy. However, 32.0% (58/181) of patients experienced adverse events, and one patient died of septic shock.

CONCLUSIONS

Infliximab is reasonably safe and effective in pediatric CD patients and should therefore be administered in refractory cases.

Growth and Adult Height in Patients with Crohn's Disease Treated with Anti-Tumor Necrosis Factor α Antibodies

Inflammation contributes to growth failure associated with inflammatory bowel diseases. Anti-TNFα therapy induces sustained remission and short-term improvements in height velocity and/or height standard deviation score (H-SDS) patients with Crohn's disease. The purpose of this study was to evaluate growth and adult height in patients with Crohn's disease taking maintenance infliximab or adalimumab therapy.This university-hospital based retrospective study included 61 patients, with a median follow-up of 2.6 years (2.0; 3.3). 38 patients (62%) reached their adult height. H-SDS was collected at diagnosis and together with disease activity markers (Harvey-Bradshaw Index, albumin, and C-reactive protein) at treatment initiation (baseline), and follow-up completion. Wilcoxon's signed-rank test was chosen for comparisons. Median H-SDS decreased from diagnosis to baseline (-0.08 [-0.73; +0.77] to -0.94 [-1.44; +0.11], p<0.0001) and then increased to follow-up completion (-0.63 [-1.08; 0.49], p = 0.003 versus baseline), concomitantly with an improvement in disease activity. Median adult H-SDS was within the normal range (-0.72 [-1.25; +0.42]) but did not differ from baseline H-SDS and was significantly lower than the target H-SDS (-0.09 [-0.67; +0.42], p = 0.01). Only 2 (6%) males had adult heights significantly below their target heights (10.5 and -13.5 cm [-1.75 and -2.25 SD]). In conclusion, anti-tumor necrosis factor α (TNF) therapy prevented loss of height without fully restoring the genetic growth potential in this group of patients with CD. Earlier treatment initiation might improve growth outcomes in these patients.

Paediatric Crohn Disease: Disease Activity and Growth in the BELCRO Cohort After 3 Years Follow-up

OBJECTIVE

The Belgian registry for paediatric Crohn disease (BELCRO) cohort is a prospective, multicentre registry for newly diagnosed paediatric patients with Crohn disease (CD) (<18 years) recruited from 2008 to 2010 to identify predictive factors for disease activity and growth.

METHODS

Data from the BELCRO database were evaluated at diagnosis, 24 and 36 months follow-up.

RESULTS

At month 36 (M36), data were available on 84 of the 98 patients included at diagnosis. Disease activity evolved as follows: inactive 5% to 70%, mild 19% to 24%, and moderate to severe 76% to 6%. None of the variables such as age, sex, diagnostic delay, type of treatment, disease location, disease activity at diagnosis, and growth were associated with disease activity at M36. Paediatricians studied significantly less patients with active disease at M36 compared with adult physicians. Sixty percent of the patients had biologicals as part of their treatment at M36. Adult gastroenterologists initiated biologicals significantly earlier. They were the only factor determining biologicals' initiation, not disease location or disease severity at diagnosis. Median body mass index (BMI) z score evolved from -0.97 (range -5.5-2.1) to 0.11 (range -3.4-2) and median height z score from -0.15 (range -3.4-1.6) to 0.12 (range -2.3-2.3) at M36. None of the variables mentioned above influenced growth over time.

CONCLUSIONS

Present treatment strategies lead to good disease control in the BELCRO cohort after 3 years. Logistic regression analysis did not show any influence of disease location or present treatment strategy on disease activity and growth, but patients under paediatric care had significantly less severe disease at M36.

Identifying Patients at High Risk of Loss of Response to Infliximab Maintenance Therapy in Paediatric Crohn's Disease

BACKGROUND AND AIMS

Loss of response to infliximab resulting in discontinuation of therapy is a frequent problem encountered in paediatric Crohn's disease. Although identifying patients at risk of failure could have important implications for follow-up, literature in this area remains sparse. Our primary aim was to identify predictors of loss of response to infliximab among patients who were responders to induction. The secondary aim was to identify predictors of non-response to induction.

METHODS

A retrospective cohort of patients with paediatric Crohn's disease treated with infliximab between 2000 and 2013 was followed until loss of response to infliximab or transfer to adult care. Predictors of response to induction therapy were studied by multivariate logistic regression. Time to treatment failure was analysed with a multivariate Cox model.

RESULTS

Two-hundred and forty-eight patients were eligible for the study. Of these, 196 (79%) were responders to induction (57% clinical remission and 22% clinical response) and 52 (21%) were non-responders. Steroid resistance was the only variable independently associated with primary non-response (odds ratio [OR] 4.57, 95% confidence interval [CI] 1.67-12.50, p = 0.002). Thirty-one of the 196 responders discontinued infliximab due to loss of response after a mean of 1.6±1.3 years of treatment. Predictors of loss of response were level of response to induction (clinical response vs clinical remission, hazard ratio [HR] 3.74, 95% CI 1.80-7.80, p = 0.0004) and isolated colonic disease (HR 2.72, 95% CI 1.30-5.71, p = 0.008).

CONCLUSIONS

Patients who fail to achieve clinical remission after induction and/or who have isolated colonic disease are at increased risk of loss of response to infliximab.

Use of Anti-TNFα Agents and Time to First-time Surgery in Paediatric Patients with Ulcerative Colitis and Crohn's Disease

BACKGROUND AND AIMS

It is debated whether the need for surgery has changed following introduction of anti-TNFα agents in the treatment of paediatric ulcerative colitis [UC] and Crohn's disease [CD]. We aimed to describe the implementation of anti-TNFα agents in paediatric patients, and the need of first-time surgery before and after introduction of anti-TNFα agents.

METHODS

In the Danish National Patient Registry, we identified incident paediatric patients diagnosed from 1998. We calculated the proportion of patients receiving anti-TNFα agents within 5 years from diagnosis, and the cumulative 5 year proportion of surgery, according to calendar periods of diagnosis.

RESULTS

At the end of our study period [2007 and 2008], 29-41% of CD children were treated with anti-TNFα agents within 5 years, and for UC children 17-19%. In 1278 CD patients, the 5 year cumulative proportions of surgery were 14.6-15.6% for children diagnosed in 1998-2008 and 9.7% (95% confidence interval [CI]: 6.7-13.7) for those diagnosed in 2009-2013. In 1468 UC patients, the cumulative proportion of surgery suggested a decline in patients diagnosed after mid 2005, and the hazard ratio of surgery was 0.64 [95% CI: 0.47-0.86] after the introduction of anti-TNFα agents compared with before. For UC patients diagnosed in 2009-2013, the 5 year cumulative proportion of surgery was 7.6% [95% CI: 5.2-11.2].

CONCLUSIONS

This nationwide study showed an extensive use of anti-TNFα agents at the end of our study period. For UC children, our data suggest a decline in the proportion of surgery in the period of increasing use of anti-TNFα agents.

The Risk of Relapse after Anti-TNF Discontinuation in Inflammatory Bowel Disease: Systematic Review and Meta-Analysis

OBJECTIVES

To perform a meta-analysis of the risk of relapse after discontinuation of anti-tumor necrosis factor (anti-TNF) therapy in patients with Crohn's disease (CD) and ulcerative colitis (UC), to evaluate risk factors for relapse, and to assess the response to retreatment with the same anti-TNF.

METHODS

Studies evaluating the incidence of relapse after anti-TNF discontinuation in patients with CD or UC who reached clinical remission with anti-TNFs were included. Bibliographies up to January 2015 were searched. Frequency of relapse after discontinuation of anti-TNF agents was determined; meta-analyses were performed using the inverse-variance method.

RESULTS

We included 27 studies (21 infliximab and 6 infliximab/adalimumab). The overall risk of relapse after discontinuation of anti-TNF therapy was 44% for CD (95% confidence interval (CI) 36-51%; I(2)=79%; 912 patients) and 38% for UC (23-52%; I(2)=82%; 266 patients). In CD, the relapse rate was 38% at 6 months after discontinuation (short term), 40% at 12 months (medium term), and 49% at >25 months (long term). In UC, 28% of patients relapsed at 12 months. In CD, when clinical remission was the only criterion for stopping anti-TNF therapy, the relapse rate after 1 year was 42%, which decreased to 26% when endoscopic remission was also required. Retreatment with the same anti-TNF induced remission again in 80% of cases (68-91%).

CONCLUSIONS

Approximately one-third of patients with inflammatory bowel disease in remission under anti-TNF treatment relapsed 1 year after discontinuation. This proportion increased to half in the long term. In CD patients, the risk of relapse was lower when the criterion for discontinuation was endoscopic remission and not only clinical remission. Response to retreatment with the same anti-TNF agent was favorable.

The association of infliximab trough levels with disease activity in pediatric inflammatory bowel disease

OBJECTIVE

Low serum trough levels (TLs) of infliximab (IFX) and antibodies to IFX (ATIs) are associated with the loss of therapeutic response in adults with inflammatory bowel disease (IBD) receiving IFX. Until now, pediatric data are scarce. Therefore, we aimed to cross-sectionally investigate the association between ATIs and IFX TLs, and clinical and biochemical disease activity in children receiving IFX for IBD.

MATERIAL AND METHODS

Children aged <18 years receiving IFX maintenance treatment for Crohn's disease (CD) or ulcerative colitis (UC) at three Dutch hospitals were included. Prior to two consecutive IFX infusions, IFX TLs and ATI levels were measured. Clinical disease activity was determined by Pediatric Crohn's Disease Activity Index (PCDAI) and Pediatric Ulcerative Colitis Activity Index (PUCAI), for CD and UC, respectively. Biochemical disease activity was assessed by serum C-reactive protein (CRP) and fecal calprotectin (FC). Clinical remission was defined as a PUCAI or PCDAI score of <10. Therapeutic range of IFX was considered 3-7 µg/ml.

RESULTS

Thirty-nine patients were included (31 CD; 16 females). Median age was 15 years. Median IFX TL was 3.5 µg/ml [IQR 2-7]. Subtherapeutic and supratherapeutic TLs were found in 38% and 23% of children, respectively. ATIs were detected in four patients. A correlation was found between IFX TL and CRP [rs = -0.51; p < 0.01] and FC [rs = -0.49; p < 0.01]. However, when only clinical disease activity was considered, no difference in median TL was found between remission and active disease (resp. 3.5 µg/ml [IQR 2-5] and 2.3 µg/ml [IQR 0.3-4.6]; p = 0.2).

CONCLUSIONS

IFX TLs are related to biochemical markers of disease activity. This could provide a rationale for monitoring TLs in children receiving IFX for IBD.

Anti-TNF Withdrawal in Inflammatory Bowel Disease

The introduction of the anti-tumor necrosis factorα agents (anti-TNFα) in clinical practice has greatly advanced the treatment of inflammatory bowel disease. The use of these medications results in durable remission in a subset of patients, preventing surgery and hospitalizations. However, there are some concerns about safety and costs associated with their long-term use. Therefore, anti-TNF withdrawal has emerged as an important consideration in clinical practice. Herein our goal was to discuss the available evidence about anti-TNFα discontinuation in IBD that could inform the clinician on the expected rates of relapse, the potential predictors of relapse, as well the response to re-treatment.

Prospective Evaluation of the Achievement of Mucosal Healing with Anti-TNF-α Therapy in a Paediatric Crohn's Disease Cohort

BACKGROUND AND AIMS

There is growing evidence that in Crohn's disease the achievement and maintenance of mucosal healing (MH) through anti-TNFα antibodies may change the natural history of the disease. Few studies evaluating such outcome as a therapeutic goal are available in paediatrics. The primary aim of the study was to assess the efficacy of biologics in obtaining MH in a paediatric Crohn's disease cohort. The secondary aims were: (1) to assess response based on early or late treatment introduction and on combination therapy with immunomodulators versus biologics alone; and (2) to evaluate clinical outcome 2 years after the second endoscopy.

METHODS

Biologic-naive paediatric Crohn's disease patients starting anti-tumour necrosis factor α (TNFα) treatment were enrolled. Patients' demographic and treatment data were recorded. Clinical [Pediatric Crohn's Disease Activity Index (PCDAI)] and endoscopic [Simple Endoscopic Score for Crohn's Disease (SES-CD)] evaluations were performed at time 0 (T0) and after 9-12 months (follow-up). Appropriate induction and maintenance therapeutic schemes were applied.

RESULTS

Thirty-seven patients were enrolled. At enrolment, mean age was 12.3 ± 3.4 years and mean disease duration was 13.0 ± 16 months. At follow-up there was a significant decrease in PCDAI and SES-CD compared with T0 (p < 0.01). No statistical difference in frequency of MH between the early and late treatment introduction groups was found. Combination therapy was superior in obtaining complete plus partial MH (p < 0.01). One and 2 years after the second endoscopy, all and 79% of patients with complete MH and 75 and 67% of those with partial MH were still in clinical remission, respectively.

CONCLUSIONS

Biologics improve mucosal lesions, apparently more effectively if given in combination with immunomodulators. MH appears to sustain a better disease course.

Systematic Review of Effects of Withdrawal of Immunomodulators or Biologic Agents From Patients With Inflammatory Bowel Disease

Little is known about the optimal duration of therapy with an anti-tumor necrosis factor (TNF) agent and/or an immunomodulator for patients with inflammatory bowel disease (IBD). We performed a systematic search of the literature to identify studies reporting after de-escalation (drug cessation or dose reduction) of anti-TNF agents and/or immunomodulators in patients in remission from IBD. Studies were reviewed according to the type of IBD and drug. Rates of relapse, factors associated with relapse, and response to re-treatment were determined. Our search yielded 6315 unique citations; we analyzed findings from 69 studies (18 on de-escalation [drug cessation or dose reduction] of immunomodulator monotherapy, 8 on immunomodulator de-escalation from combination therapy, and 43 on de-escalation of anti-TNF agents, including 3 during pregnancy) comprising 4672 patients. Stopping immunomodulator monotherapy after a period of remission was associated with high rates of relapse in patients with Crohn's disease or ulcerative colitis (approximately 75% of patients experienced a relapse within 5 years after therapy was stopped). Most studies of patients with Crohn's disease who discontinued an immunomodulator after combination therapy found that rates of relapse did not differ from those of patients who continued taking the drug (55%-60% had disease relapse 24 months after they stopped taking the immunomodulator). The only study in patients with ulcerative colitis supported continued immunomodulator use. Approximately 50% of patients who discontinued anti-TNF agents after combination therapy maintained remission 24 months later, but the proportion in remission decreased with time. Markers of disease activity, poor prognostic factors, and complicated or relapsing disease course were associated with future relapse. In conclusion, based on a systematic review, 50% or more of patients with IBD who cease therapy have a disease relapse. Further studies are required to accurately identify subgroups of patients who are good candidates for discontinuation of treatment. The decision to withdraw a drug should be made for each individual based on patient preference, disease markers, consequences of relapse, safety, and cost.

Systematic review: factors associated with relapse of inflammatory bowel disease after discontinuation of anti-TNF therapy

BACKGROUND

The discontinuation of anti-tumour necrosis factor (anti-TNF) treatment in inflammatory bowel disease (IBD) patients in remission could be considered.

AIM

To evaluate the factors associated with relapse of IBD after discontinuation of anti-TNF therapy.

METHODS

Electronic (PubMed/Embase) and manual search up to January 2015.

RESULTS

The overall risk of relapse after discontinuation of anti-TNFs (27 studies) was 44% for Crohn's disease (CD; follow-up range: 6-125 months) and 38% for ulcerative colitis (follow-up range: 6-24 months). Several factors were investigated to identify patients who are more likely to achieve long-lasting remission after anti-TNF discontinuation. The factors associated with a higher risk of relapse are younger age, smoking, longer disease duration, and fistulising perianal CD. Laboratory markers such as low haemoglobin levels, high C-reactive protein levels and high faecal calprotectin seem to increase the risk of relapse. On the other hand, low serum anti-TNF levels seem to be associated with a lower risk of flare-up. Mucosal healing seems to decrease the risk of relapse after anti-TNF discontinuation (overall, this risk is 26% at 1 year with mucosal healing and 42% without), although this observation has not been confirmed by some authors. In patients receiving escalated anti-TNF doses or receiving anti-TNFs for the prevention of post-operative CD recurrence, the risk of relapse after discontinuation is high (>75%). Re-administration of the drug in those who relapsed after stopping treatment is effective and safe.

CONCLUSIONS

A high proportion of patients with IBD relapse after discontinuation of anti-TNF treatment. As available data are insufficient to make strong recommendations on when anti-TNF therapy could be stopped, decisions should be taken on an individual basis.