Designing clinical trials in paediatric inflammatory bowel diseases: a PIBDnet commentary

Specialized and standard nutritional formulas for the dietary management of pediatric patients with Crohn's disease: a systematic literature review

INTRODUCTION

This systematic literature review (SLR) aims to compare the clinical, humanistic, and economic outcomes associated with specialized and standard nutritional formulas for the treatment of mild-to-moderate pediatric Crohn's disease.

METHODS

Search strategies were applied across MEDLINE, Cochrane and Web of Science (January 2000-October 2023) and recent congress proceedings (January 2021-October 2023). PRISMA-P guidelines were followed. Quality assessment evaluated risk of bias.

RESULTS

Twenty-three unique studies met the inclusion criteria. Nineteen studies (754 patients) evaluated specialized formula, 10 assessed standard formula (246 patients). Mucosal healing (7 studies), induction (20 studies) and maintenance of remission (9 studies) were reported over various timeframes. High proportions of patients who received specialized formula achieved mucosal healing (63-89% 8 weeks; 25-74% 10 weeks), and remission (50-100% 8 weeks). Specialized formula sustained remission (34-62.5% 6 months and 24-87.5% 1 year). Results were not directly comparable with standard formula due to significant heterogeneity in study methodology, patient populations, and remission definition.

CONCLUSIONS

The evidence predominantly supports the benefits of specialized formula in inducing mucosal healing, remission, and sustaining positive outcomes across multiple timepoints. Direct comparison of nutritional interventions is required to further support the findings of this SLR.Protocol registration: PROSPERO CRD42023472370.

Ustekinumab is safe and effective in pediatric patients with Crohn's disease

OBJECTIVES

Real-world data on ustekinumab for the treatment of pediatric Crohn's disease (CD) are limited. This study sought to evaluate the effectiveness, long-term durability, and safety of ustekinumab in the treatment of children with CD.

METHODS

A retrospective longitudinal cohort study of children with CD treated with ustekinumab from two large centers between 2015 and 2020 was performed. The primary outcome was frequency of steroid-free clinical remission at 1 year. Secondary outcomes included time to steroid-free clinical remission, frequency of clinical and biochemical remission, drug escalation and discontinuation, serum level data, and adverse events. Standard descriptive and comparative statistics were performed. Logistic regression was used to identify factors associated with steroid-free remission at 1 year. Kaplan-Meier curves were used to visualize time-to-event relationships for outcomes.

RESULTS

A total of 101 patients were included. Median follow-up time on ustekinumab was 16.6 months (interquartile range [IQR]: 8.71-31.2) with drug failure in 28% at 1 year. Fifty-nine patients were in steroid-free clinical remission at 1 year. Higher baseline disease activity (odds ratio [OR]: 0.91 (95% confidence interval [CI]: 0.84-0.97), p = 0.01) and stricturing/penetrating disease phenotype (OR: 0.14 (95% CI: 0.03-0.65), p = 0.02) were associated with decreased likelihood of steroid-free clinical remission at 1-year. Ustekinumab drug escalation occurred in 70% of patients, and after escalation, 50 (70%) achieved clinical remission, and 49 (69%) achieved steroid-free remission at the last follow-up. Adverse events were rare and did not require therapy discontinuation.

CONCLUSIONS

Ustekinumab is effective and safe in the treatment of children with CD. Escalation of therapy occurs frequently but results in sustained durability.

Biologics in the management of pediatric inflammatory bowel disease: When and what to choose

Pediatric inflammatory bowel disease (PIBD) is a chronic inflammatory disorder of the gastrointestinal tract, with rising global incidence and prevalence. Over the past two decades, biologics have added to the therapeutic armamentarium and revolutionized the approach to treatment of inflammatory bowel disease. The available biologics include monoclonal antibodies which target inflammatory cytokines (anti-tumor necrosis factor alpha, anti-interleukin 12/23) or recruitment of leucocytes to the gastrointestinal tract (anti-alpha4beta7 integrin) and small molecules (Janus kinase inhibitors, sphingosine 1-phosphate-inhibitors) which modify the proinflammatory signaling. Considering their potential disease-modifying ability, recent pediatric guidelines from the West have advocated upfront use of biologics in appropriate clinical scenarios as a top-down approach rather than the conventional step-up approach. Although real-world studies are available regarding the clinical efficacy of biologics in PIBD, there is paucity of long-term outcome and safety data in children. Also, little information is available about the best approach in the newly industrialized - developing countries where PIBD is rising but at the same time, infections are prevalent and resources are limited. In this review, we summarize the efficacy and safety profile of biologics and small molecule drugs and discuss the challenges in the management of PIBD, especially in the developing world, and future directions.

Operating Properties of Disease Activity Indices in Pediatric Inflammatory Bowel Disease: A Systematic Review

BACKGROUND

Accurate, reliable, and responsive disease activity indices are important to streamline drug approval and treatment modalities for pediatric inflammatory bowel disease (pIBD). We aimed to identify all scoring indices used in pIBD randomized controlled trials (RCTs) and to evaluate their operating properties.

METHODS

MEDLINE, EMBASE, and CENTRAL were searched on December 6, 2022, to identify studies evaluating clinical, endoscopic, imaging, or patient-reported outcome measures (PROMs) in pIBD including Crohn's disease (CD) and ulcerative colitis (UC). Validity, reliability, responsiveness, and feasibility were summarized.

RESULTS

Seventy RCTs evaluating pIBD indices were identified. Forty-one studies reported on the operating properties of 14 eligible indices (n = 9 CD, n = 5 UC). The Pediatric Crohn's Disease Activity Index (PCDAI) varied widely in terms of validity and reliability and was less feasible overall. In contrast, the Mucosal Inflammation Noninvasive Index, which includes fecal calprotectin, had better operating properties than the PCDAI. The Simplified Endoscopic Mucosal Assessment of Crohn's Disease appears more feasible and had similar operating properties than the longer Simple Endoscopic Score for Crohn's Disease. The Pediatric Ulcerative Colitis Activity Index was feasible, valid, and reliable, but responsiveness needs to be evaluated further. The Endoscopic Mayo score and the Ulcerative Colitis Endoscopic Index of Severity were reliable, but validity and responsiveness need to be evaluated further. Imaging and PROMs/quality of life indices need further evaluation.

CONCLUSIONS

The operating properties of pIBD clinical trial end points varied widely. These results highlight the need for further validation and development of novel indices.

Harms with placebo in trials of biological therapies and small molecules as maintenance therapy in inflammatory bowel disease: a systematic review and meta-analysis

BACKGROUND

Randomised placebo-controlled trials for the induction of inflammatory bowel disease (IBD) remission involve potential harms to those receiving placebo. Whether these harms are also apparent with placebo during maintenance of remission trials in IBD is unclear. We aimed to examine the potential harms associated with receiving placebo in trials of licensed biologics and small molecules for maintenance of remission of ulcerative colitis and luminal Crohn's disease in a meta-analysis.

METHODS

We performed a systematic review and meta-analysis. We searched several medical literature databases including MEDLINE (from Jan 1, 1946, to May 31, 2024), Embase and Embase Classic (Jan 1, 1947, to May 31, 2024), and the Cochrane Central Register of Controlled Trials from database inception to May 31, 2024, for randomised placebo-controlled trials of licensed biologics and small molecules for maintenance of remission in adults with IBD reporting data on adverse events over a period of 20 weeks or more. There were no language restrictions or prespecified exclusion criteria. We extracted summary data and pooled data using a random-effects model for any treatment-emergent adverse event, drug-related adverse event, infection, worsening of IBD activity, withdrawal due to adverse events, serious adverse events, serious infection, serious worsening of IBD activity, or venous thromboembolic events, reporting relative risks (RRs) for placebo versus active drug with 95% CIs for each outcomes. The protocol for this meta-analysis was registered with PROSPERO (CRD42024542624).

FINDINGS

Our search identified 10 826 citations, of which 45 trials including 16 562 patients (10 319 [62·3%] receiving active drug and 6243 [37·7%] placebo) were eligible. The risks of any treatment-emergent adverse event (7297/9546 [76·4%] patients on active drug vs 4415/5850 [75·5%] on placebo; RR 1·01, 95% CI 0·99-1·04; I2 =47%), serious infection (260/10 242 [2·5%] vs 155/6149 [2·5%]; 0·97, 0·79-1·19; I2 =0%), or venous thromboembolic event (12/4729 [0·3%] vs 9/2691 [0·3%]; 0·72, 0·31-1·66; I2 =0%) were not significantly lower with active drug than placebo. The risks of any infection (3208/8038 [39·9%] vs 1713/4809 [35·6%]; 1·14, 1·05-1·23; I2 =60%) or any drug-related adverse event (1094/2997 [36·5%] vs 609/1950 [31·2%]; 1·24, 1·02-1·50; I2 =75%) were higher with active drug than placebo. However, the risks of any worsening of IBD activity (1038/8090 [12·8%] vs 1181/5191 [22·8%]; 0·58, 0·52-0·64; I2 =40%), any withdrawal due to adverse events (610/10 282 [5·9%] vs 561/6207 [9·0%]; 0·71, 0·60-0·84; I2 =43%), any serious adverse events (1066/10 292 [10·4%] vs 742/6198 [12·0%]; 0·85, 0·77-0·94; I2 =17%), or any serious worsening of IBD activity (101/5707 [1·8%] vs 143/3640 [3·9%]; 0·55, 0·42-0·71; I2 =0%) were lower with active drug than placebo. 21 randomised controlled trials were judged as low risk of bias across all domains.

INTERPRETATION

In maintenance of remission trials in IBD, placebo was associated with some clinically significant potential harms. Patients should be counselled about these before participating in clinical trials and consideration given to alternative designs to test novel drugs in IBD.

FUNDING

None.

Harms with placebo in trials of biological therapies and small molecules as induction therapy in inflammatory bowel disease: a systematic review and meta-analysis

BACKGROUND

Randomised placebo-controlled trials are the gold standard to assess novel drugs in ulcerative colitis and Crohn's disease. However, there might be risks associated with receiving placebo. We aimed to examine the harms associated with receiving placebo in trials of licensed biologics and small molecules for the induction of remission in ulcerative colitis and luminal Crohn's disease in a meta-analysis.

METHODS

We performed a systematic review and meta-analysis. We searched MEDLINE, Embase, Embase Classic, and the Cochrane Central Register of Controlled Trials from database inception to May 30, 2024, for randomised placebo-controlled trials of licensed biologics and small molecules for induction of remission in adults (≥18 years) with moderately to severely active ulcerative colitis or luminal Crohn's disease reporting data on adverse events over a minimum treatment period of 4 weeks. There were no prespecified study exclusion criteria. We extracted summary data and pooled data using a random-effects model for any treatment-emergent adverse event, any drug-related adverse event, infection, worsening of inflammatory bowel disease (IBD) activity, withdrawal due to adverse events, serious adverse events, serious infection, serious worsening of IBD activity, or venous thromboembolic events (VTEs), reporting relative risks (RRs) with 95% CIs. The protocol for this meta-analysis was registered with PROSPERO (CRD42024527341).

FINDINGS

The search identified 10 826 citations, of which 47 trials including 20 987 patients (14 267 [68·0%] receiving active drug and 6720 [32·0%] receiving placebo) were eligible. The risk of any treatment-emergent adverse event was no different with active drug than with placebo (7660/14 267 [53·7%] patients on active drug vs 3758/6720 [55·9%] on placebo; RR 0·97, 95% CI 0·94-1·00; I2 =36%). However, the risks of worsening of IBD activity (563/13 473 [4·2%] vs 530/6252 [8·5%]; 0·48, 0·40-0·59; I2 =54%), withdrawal due to adverse event (401/13 363 [3·0%] vs 299/6267 [4·8%]; 0·62, 0·48-0·79; I2 =46%), serious adverse event (682/14 267 [4·8%] vs 483/6720 [7·2%]; 0·69, 0·59-0·80; I2 =30%), serious infection (140/14 194 [1·0%] vs 91/6647 [1·4%]; 0·67, 0·50-0·89; I2 =0%), serious worsening of IBD activity (187/11 271 [1·7%] vs 189/5056 [3·7%]; 0·45, 0·34-0·60; I2 =27%), or VTEs (13/7542 [0·2%] vs 12/2981 [0·4%]; 0·45, 0·21-0·94; I2 =0%) were all significantly lower with active drug than placebo. Numbers needed to treat with active drug to avoid these potentially serious adverse events ranged from 23 for worsening of IBD activity to 452 for VTEs. 27 randomised controlled trials were judged as low risk of bias across all domains.

INTERPRETATION

Patients with moderately to severely active IBD receiving placebo are more likely to experience significant worsening of IBD activity and some serious adverse events, which might relate to a reduction in risk of these events with active drug. Patients should be counselled about these potential harms, and alternative trial designs to mitigate these harms should be considered.

FUNDING

None.

Outcomes in Adult Inflammatory Bowel Disease Clinical Trials: Assessment of Similarity Among Participants with Adolescent-onset and Adult-onset Disease

BACKGROUND AND AIMS

Most paediatric inflammatory bowel disease [IBD] studies are performed after medications are approved in adults, and the majority of participants in these studies are adolescents. We hypothesised that adolescent-onset IBD is not fundamentally different from adult-onset IBD. If this is correct, the value of delaying access to novel drugs in adolescents becomes questioned.

METHODS

Data from 11 randomised, double-blind, placebo-controlled, adult Phases 2 and 3 trials of four biologics were analysed. Participants were categorised as having adolescent- or adult-onset disease [diagnosed 12 to <18, or ≥18 years]. Multivariable modelling explored the association between age at diagnosis and response to treatment, after adjustment for disease duration, extent, and severity at baseline. Data from dose arms were pooled to evaluate similarity of therapeutic response between adolescent- and adult-onset IBD within the same trial [not between doses or across trials]. Ratios of odds ratios [ORs] between the two groups were evaluated.

RESULTS

Data from 6283 study participants (2575 with Crohn's disease [CD], 3708 with ulcerative colitis [UC]) were evaluated. Of 2575 study participants with CD, 325 were 12-<18 years old at diagnosis; 836 participants [32.4%] received placebo. Of 3708 participants with UC, 221 were 12-<18 years old at diagnosis; 1212 [33%] were receiving placebo. The majority of the ratios of ORs were within 2-fold, suggesting that responses in adolescent- and adult-onset participants are generally similar.

CONCLUSION

Data presented lend support for extrapolating efficacy of biologics from adults to adolescents with IBD, which would facilitate earlier labelling and patient access.

Treatment of inflammatory bowel disease with steroid-sparing medications is age-dependent - Results from a Danish nationwide cohort study, 2000-2018

BACKGROUND

Paediatric-onset and elderly-onset inflammatory bowel disease (IBD) present unique treatment challenges.

AIMS

We investigated treatment patterns following a first and second course of systemic steroids in paediatric- and elderly-onset IBD and compared them to adult-onset IBD.

METHODS

All patients diagnosed with Crohn's disease (CD) or ulcerative colitis (UC) between 2000 and 2018 were identified through the Danish healthcare registries. Patients were divided into groups based on their age at diagnosis. Kaplan-Meier plots were prepared for medications and surgeries after diagnosis and after the first and second courses of systemic steroids. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated using multivariate Cox regression analysis for steroid-sparing medications.

RESULTS

1851 CD (13%) and 1687 (6%) UC patients were paediatric-onset, while 2952 (20%) CD and 5812 (23%) UC patients were elderly-onset. Paediatric-onset more frequently received immunomodulators [CD: HR: 1.64, CI: 1.52-1.77, UC: HR: 2.29, CI: 2.02-2.61] and biologics [CD: HR: 1.43, CI: 1.25-1.65, UC: HR: 1.27, CI: 0.99-1.64], while elderly-onset less frequently received immunomodulators [CD: HR: 0.39, CI: 0.35-0.44, UC: HR: 0.58, CI: 0.50-0.67] and biologics [CD: HR: 0.19, CI: 0.14-0.25, UC: HR: 0.36, CI: 0.27-0.48] compared to adult-onset age groups. After two courses of systemic steroids, elderly-onset still received less steroid-sparing medications. High frailty was associated with lower usage of medications for elderly-onset.

CONCLUSION

There are significant differences in the use of steroid-sparing medication between age of onset, even after two courses with systemic steroids. High frailty could account for some of these differences in elderly-onset IBD.

Unlocking the Potential: A Systematic Review of Master Protocol in Pediatrics

The use of master protocols allows for innovative approaches to clinical trial designs, potentially enabling new approaches to operations and analytics and creating value for patients and drug developers. Pediatric research has been conducted for many decades, but the use of novel designs such as master protocols in pediatric research is not well understood. This study aims to provide a systematic review on the utilization of master protocols in pediatric drug development. A search was performed in September 2022 using two data sources (PubMed and ClinicalTrials.gov) and included studies conducted in the past10 years. General study information was extracted such as study type, study status, therapeutic area, and clinical trial phase. Study characteristics that are specific to pediatric studies (such as age of the participants and pediatric drug dosing) and important study design elements (such as number of test drug arms and whether randomization and/or concurrent control was used) were also collected. Our results suggest that master protocol studies are being used in pediatrics, with platform and basket trials more common than umbrella trials. Most of this experience is in oncology and early phase studies. There is a rise in the use starting in 2020, largely in oncology and COVID-19 trials. However, adoption of master protocols in pediatric clinical research is still on a small scale and could be substantially expanded. Work is required to further understand the barriers in implementing pediatric master protocols, from setting up infrastructure to interpreting study findings.

Precision medicine in monogenic inflammatory bowel disease: proposed mIBD REPORT standards

Owing to advances in genomics that enable differentiation of molecular aetiologies, patients with monogenic inflammatory bowel disease (mIBD) potentially have access to genotype-guided precision medicine. In this Expert Recommendation, we review the therapeutic research landscape of mIBD, the reported response to therapies, the medication-related risks and systematic bias in reporting. The mIBD field is characterized by the absence of randomized controlled trials and is dominated by retrospective observational data based on case series and case reports. More than 25 off-label therapeutics (including small-molecule inhibitors and biologics) as well as cellular therapies (including haematopoietic stem cell transplantation and gene therapy) have been reported. Heterogeneous reporting of outcomes impedes the generation of robust therapeutic evidence as the basis for clinical decision making in mIBD. We discuss therapeutic goals in mIBD and recommend standardized reporting (mIBD REPORT (monogenic Inflammatory Bowel Disease Report Extended Phenotype and Outcome of Treatments) standards) to stratify patients according to a genetic diagnosis and phenotype, to assess treatment effects and to record safety signals. Implementation of these pragmatic standards should help clinicians to assess the therapy responses of individual patients in clinical practice and improve comparability between observational retrospective studies and controlled prospective trials, supporting future meta-analysis.

The Future of Advanced Therapies for Pediatric Crohn's Disease

Pediatric Crohn's disease commonly presents with moderate-to-severe intestinal inflammation with a greater risk of complications if remission is not achieved. Anti-tumor necrosis factor therapies have offered the possibility of deep and durable remission; however, many children do not respond or no longer respond over time. Further, some children do not require broader systemic immunosuppression to achieve remission and are better served by an alternative treatment strategy. Proper utilization of advanced biologic and small-molecule therapies, which have become available for adult patients since anti-tumor necrosis factor medications, is paramount for tighter disease control for a large proportion of children. Newer advanced therapies such as anti-integrin and anti-interleukin biologics, and several small-molecule agents capitalize on various mechanisms through narrower immunologic targets and reduced immunogenicity. Given limited regulatory approvals of these agents for use in children with Crohn's disease, clinicians continue to rely on data extrapolated from clinical trials in adult patients, sparse pediatric studies, and a growing real-world experience for treatment selection and optimization. In this article, we discuss currently available treatment options, pipeline drugs, and relevant data as they pertain to some of the most pressing clinical challenges faced in treating pediatric Crohn's disease.

Review article: Externally derived control arms-An opportunity for clinical trials in inflammatory bowel disease?

BACKGROUND

One of the greatest challenges in the current IBD clinical trial landscape is, perhaps, the recruitment and retention of eligible participants. Seamless testing of promising investigational compounds is paramount to address unmet needs, but this is hindered by a number of barriers, particularly patient concerns of placebo assignment.

AIMS

To review the use of novel trial designs leveraging externally derived data to synthetically create control groups or augment existing ones, and to summarise the regulatory position on the use of external controls for market authorisation.

METHODS

We conducted a PubMed literature search without restriction using search terms such as 'external controls' and 'historical controls' to identify relevant articles.

RESULTS

External controls are increasingly being used outside the context of cancer and rare diseases, including IBD, and increasingly recognised by regulatory bodies. Such designs, particularly in earlier phase trials, can inform key nodes in drug development and permit evaluating efficacy of interventions without combating the ethical and numerical enrolment challenges described. However, the lack of randomisation and blinding subjects them to significant bias. Groups require robust statistical and computational approaches to ensure patient-level data across groups are adequately balanced.

CONCLUSIONS

While this approach has several pitfalls, and is not robust enough to replace traditional randomised, placebo-controlled trials, it may offer a compromise to address key research questions at a more rapid pace, with fewer patients, and lower cost.

Health Care Maintenance in Pediatric Inflammatory Bowel Disease

Patients with pediatric inflammatory bowel disease (pIBD) are at an increased risk for complications and comorbidities including infection, nutritional deficiencies, growth delay, bone disease, eye disease, malignancy, and psychologic disorders. Preventative health maintenance and monitoring is an important part to caring for patients with pIBD. Although practice is variable and published study within pIBD is limited, this article summarizes the important field of health-care maintenance in pIBD. A multidisciplinary approach, including the gastroenterologist provider, primary care provider, social worker, psychologist, as well as other subspecialists is necessary.

Effectiveness and Safety of Ustekinumab for Pediatric Inflammatory Bowel Disease: A Systematic Review

BACKGROUND

The use of ustekinumab in pediatric patients with inflammatory bowel disease (IBD) is off-label and the data are limited. We conducted a systematic review evaluating the efficacy and safety of ustekinumab in pediatric IBD.

METHODS

We systematically searched PubMed, EMBASE and Cochrane databases for studies of ustekinumab in children and adolescents with IBD investigating clinical remission, clinical response, corticosteroid-free (CS-free) remission, endoscopic remission/response, or safety up to March 17, 2023. A random-effects model was used for calculating summary estimates.

RESULTS

Eleven studies, comprising 370 patients were included. For Crohn's disease (CD), the pooled clinical remission rates were 34% (73/204) at 8-16 weeks and 46% (60/129) at 1 year. The pooled CS-free clinical remission rates were 23% (10/44) at 8-16 weeks and 45% (42/96) at 1 year. For ulcerative colitis (UC)/IBD unspecified (IBD-U), the pooled CS-free clinical remission rates were 24% (6/25) at 26 weeks and 46% (16/35) at 1 year. Endoscopic remission was found in 0-37.5% of CD and 63.6% of UC. Serious adverse events were reported in 3.5% of patients. About one half of patients required reduction in dose intervals and 62.75% patients could continue ustekinumab therapy at 1 year or final visit.

CONCLUSIONS

According to low-quality evidence mainly from cohort studies and case series, approximately one half of patients with CD and UC/IBD-U achieved remission at 1 year. Ustekinumab has a reasonable safety profile and dose optimization is frequently required. Data on the long-term benefit and high-quality evidence are still needed.

The State of Clinical Trials in Pediatric Inflammatory Bowel Disease

The gap between available biologic and small molecule therapy for inflammatory bowel disease for children and adults remains large. At present only 2 anti-TNF agents are licensed for pediatric use compared with multiple other agents with different mechanisms of action being used in adults. The reasons are many but largely revolve around the inadequate acceptance of adult efficacy data to children, and the reluctance of industry to commit to early pediatric drug development for fear of inadequate return on investment. We suggest common sense steps that need to be taken to improve this situation.

The Role of Noninvasive Surrogates of Inflammation in Monitoring Pediatric Inflammatory Bowel Diseases: The Old and the New

Effectiveness of limited available therapies for pediatric inflammatory bowel disease has reached stagnation. Previous non-invasive monitoring strategies have relied upon cumbersome tools to evaluate clinical symptoms and biochemical markers that do not reflect endoscopic activity or respond quickly to treatments. Novel, patient-centric, and highly accurate, monitoring strategies with a focus on intestinal ultrasound for a direct, precise monitoring of activity to achieve disease modification are now possible. Ultimately, research on the optimal tight control monitoring strategies, individualized to each pediatric inflammatory bowel disease patient, are in development and offer a hope to potential therapeutic ceiling breakthrough on the horizon.

Paediatric Inflammatory Bowel Disease: A Multi-Stakeholder Perspective to Improve Development of Drugs for Children and Adolescents

BACKGROUND AND AIMS

Despite recent approvals for new drugs to treat adults with Crohn's disease or ulcerative colitis, there are only two approved advanced treatment options [infliximab and adalimumab] for children with inflammatory bowel disease [IBD]. There are many potential new therapies being developed for adult and paediatric IBD. Moreover, regulatory agencies in both the European Union and USA have processes in place to support the early planning and initiation of paediatric studies. Nevertheless, unacceptable delays in approvals for use of drugs in children persist, with an average 7-year gap, or longer, between authorization of new IBD drugs for adults and children.

METHODS

A 2-day virtual meeting was held during April 14-15, 2021 for multi-stakeholders [clinical academics, patient community, pharmaceutical companies and regulators] to discuss their perspectives on paediatric drug development for IBD.

RESULTS

The multi-stakeholder group presented, discussed and proposed actions to achieve expediting the approval of new drugs in development for paediatric IBD.

CONCLUSIONS

Collaborative action points for all stakeholders are required to make progress and facilitate new drug development for children with IBD.

Ustekinumab for steroid-refractory pancolitis in a biologically naive child: A case report and literature review

Ustekinumab is not recommended for the treatment of children with inflammatory bowel disease, but its off-label use is increasing despite a lack of pediatric pharmacokinetic data. The purpose of this review is to evaluate the therapeutic effects of Ustekinumab on children with inflammatory bowel disease and to recommend the best treatment regimen. Ustekinumab was the first biological treatment for a 10-year-old Syrian boy with steroid-refractory pancolitis who weighed 34 kg. A 260 mg/kg (~6 mg/kg) intravenous dose was followed by 90 mg of subcutaneous Ustekinumab at week 8 (induction). The patient was supposed to receive the first maintenance dose after twelve weeks, but after ten weeks, he developed acute severe ulcerative colitis which was managed according to treatment guidelines, except receiving 90 mg of subcutaneous Ustekinumab when he was discharged. The maintenance dose of 90 mg subcutaneous Ustekinumab was intensified to every 8 weeks. Throughout the treatment period, he achieved and maintained clinical remission. In pediatric inflammatory bowel disease, a dose of intravenous ~6 mg/kg of Ustekinumab is a common induction regimen, while children weighing < 40 kg may require a dose of 9 mg/kg. For maintenance, children may require 90 mg of subcutaneous Ustekinumab every 8 weeks. The outcome of this case report is interesting with improved clinical remission and highlighting the expansion of clinical trials on Ustekinumab for children.

Outcomes, dosing, and predictors of vedolizumab treatment in children with inflammatory bowel disease (VEDOKIDS): a prospective, multicentre cohort study

BACKGROUND

Scarce data are available on the use of vedolizumab in children with inflammatory bowel disease (IBD). We aimed to evaluate the safety, effectiveness, and dosing of vedolizumab to induce remission of IBD.

METHODS

VEDOKIDS was a paediatric, multicentre, prospective cohort study done in 17 centres in six countries. We report the 14-week outcomes as the first analyses of the planned 3-year follow-up of the VEDOKIDS cohort. Children (aged 0-18 years) with IBD who had commenced vedolizumab were followed up at baseline and at 2, 6, and 14 weeks. Children were managed according to local prescribing practices without standardisation of dosing or criteria for escalation, but the study protocol suggested dosing of 177 mg/m² body surface area (up to 300 mg maximum). The primary outcome was steroid-free and exclusive enteral nutrition-free remission at 14 weeks, analysed according to the intention-to-treat principle. Serum samples were taken for analysis of drug concentration and faecal calprotectin at baseline, and at 2, 6, and 14 weeks. Adverse events were recorded in real time and classified as severe or non-severe and related or unrelated to vedolizumab. This study is registered with ClinicalTrials.gov, NCT02862132.

FINDINGS

Between May 19, 2016, and April 1, 2022, 142 children (76 [54%] girls and 66 [46%] boys; mean age 13·6 years [SD 3·6]) were enrolled. 65 (46%) children had Crohn's disease, 68 (48%) had ulcerative colitis, and nine (6%) had unclassified IBD (those with unclassified IBD were analysed with the ulcerative colitis group). 32 (42% [95% CI 30-54]) of 77 children with ulcerative colitis and 21 (32% [23-45]) of 65 children with Crohn's disease were in steroid-free and exclusive enteral nutrition-free remission at 14 weeks. Median drug concentrations at week 14 were higher in children with ulcerative colitis than in those with Crohn's disease (11·5 μg/mL [IQR 5·5-18·1] vs 5·9 μg/mL [3·0-12·7]; p=0·006). In children who weighed less than 30 kg, the optimal drug concentration associated with steroid-free and exclusive enteral nutrition-free clinical remission was 7 μg/mL at week 14 (area under the curve 0·69 [95% CI 0·41-0·98]), corresponding to a dose of 200 mg/m² body surface area or 10 mg/kg. 32 (23%) of 142 children reported at least one adverse event, the most common were headache (five [4%]), myalgia (four [3%]), and fever (three [2%]). None of the adverse events were classified as severe, and only two (1%) patients discontinued treatment due to adverse events.

INTERPRETATION

Vedolizumab showed good safety and effectiveness at inducing remission in children with IBD at 14 weeks, especially those with ulcerative colitis. Vedolizumab should be considered in children when other approved drug interventions for IBD are unsuccessful. In children who weigh less than 30 kg, vedolizumab should be dosed by the child's body surface area (200 mg/m²) or weight (10 mg/kg).

FUNDING

The European Crohn's and Colitis Organization, the European Society for Paediatric Gastroenterology Hepatology and Nutrition, and Takeda.

Pediatric Inflammatory Bowel Disease

Inflammatory bowel diseases (IBDs) are chronic, immune-mediated disorders that include Crohn's disease and ulcerative colitis. A pediatric onset of disease occurs in about 10% of all cases. Clinical presentation of IBD with rectal bleeding or perianal disease warrants direct referral for endoscopic evaluation. In the absence of red-flag symptoms, a combination of patient history and blood and fecal biomarkers can help to distinguish suspected IBD from other causes of abdominal pain or diarrhea. The therapeutic management of pediatric IBD has evolved by taking into account predictors of poor outcome, which justifies the upfront use of anti-tumor necrosis factor therapy for patients at high risk for complicated disease. In treating patients with IBD, biochemical or endoscopic remission, rather than clinical remission, is the therapeutic goal because intestinal inflammation often persists despite resolution of abdominal symptoms. Pediatric IBD comes with unique additional challenges, such as growth impairment, pubertal delay, the psychology of adolescence, and development of body image. Even after remission has been achieved, many patients with IBD continue to experience nonspecific symptoms like abdominal pain and fatigue. Transfer to adult care is a well-recognized risk for disease relapse, which highlights patient vulnerability and the need for a transition program that is continued by the adult-oriented IBD team. The general pediatrician is an invaluable link in integrating these challenges in the clinical care of patients with IBD and optimizing their outcomes. This state-of-the-art review aims to provide general pediatricians with an update on pediatric IBD to facilitate interactions with pediatric gastrointestinal specialists.

Development of a multimodal machine-learning fusion model to non-invasively assess ileal Crohn's disease endoscopic activity

BACKGROUND AND OBJECTIVE

Recurrent attentive non-invasive observation of intestinal inflammation is essential for the proper management of Crohn's disease (CD). The goal of this study was to develop and evaluate a multi-modal machine-learning (ML) model to assess ileal CD endoscopic activity by integrating information from Magnetic Resonance Enterography (MRE) and biochemical biomarkers.

METHODS

We obtained MRE, biochemical and ileocolonoscopy data from the multi-center ImageKids study database. We developed an optimized multimodal fusion ML model to non-invasively assess terminal ileum (TI) endoscopic disease activity in CD from MRE data. We determined the most informative features for model development using a permutation feature importance technique. We assessed model performance in comparison to the clinically recommended linear-regression MRE model in an experimental setup that consisted of stratified 2-fold validation, repeated 50 times, with the ileocolonoscopy-based Simple Endoscopic Score for CD at the TI (TI SES-CD) as a reference. We used the predictions' mean-squared-error (MSE) and the receiver operation characteristics (ROC) area under curve (AUC) for active disease classification (TI SEC-CD≥3) as performance metrics.

RESULTS

121 subjects out of the 240 subjects in the ImageKids study cohort had all required information (Non-active CD: 62 [51%], active CD: 59 [49%]). Length of disease segment and normalized biochemical biomarkers were the most informative features. The optimized fusion model performed better than the clinically recommended model determined by both a better median test MSE distribution (7.73 vs. 8.8, Wilcoxon test, p<1e-5) and a better aggregated AUC over the folds (0.84 vs. 0.8, DeLong's test, p<1e-9).

CONCLUSIONS

Optimized ML models for ileal CD endoscopic activity assessment have the potential to enable accurate and non-invasive attentive observation of intestinal inflammation in CD patients. The presented model is available at https://tcml-bme.github.io/ML_SESCD.html.

The Role of Master Protocols in Pediatric Drug Development

Master protocols are innovative clinical trial designs that enable new approaches to analytics and operations, creating value for patients and drug developers. To date, the use of master protocols in pediatric drug development has been limited, focused primarily on pediatric oncology with limited experience in rare and ultra-rare pediatric diseases. This article explores the application of master protocols to pediatric programs required by FDA and EMA based on adult developmental programs. These required programs involve multiple assets developed in limited pediatric populations for registrational purposes. However, these required programs include the possibility for extrapolation of efficacy and safety from the adult population. The use of master protocols is a potential solution to the challenge of conducting clinical trials in small pediatric populations provided that such use would improve enrollment or reduce the required sample size. Toward that end, Janssen and Lilly have been working on a collaborative cross-company pediatric platform trial in pediatric Crohn's disease using an innovative Bayesian analysis. We describe how two competing companies can work together to design and execute the proposed platform, focusing on selected aspects-the usefulness of a single infrastructure, the regulatory submission process, the choice of control group, and the use of pediatric extrapolation. Master protocols offer the potential for great benefit in pediatrics by streamlining clinical development, with the goal of reducing the delay in pediatric marketing approvals when compared to adults so that children have timelier access to safe and effective medications.

Metabolome Changes With Diet-Induced Remission in Pediatric Crohn's Disease

BACKGROUND & AIMS

The Crohn's disease (CD) exclusion diet (CDED) plus partial enteral nutrition (PEN) and exclusive enteral nutrition (EEN) both induce remission in pediatric CD. CDED+PEN is better tolerated and able to sustain remission. We characterized the changes in fecal metabolites induced by CDED+PEN and EEN and their relationship with remission.

METHODS

A total of 216 fecal metabolites were measured in 80 fecal samples at week (W) 0, W6, and W12, of children with mild to moderate CD in a prospective randomized trial comparing CDED+PEN vs EEN. The metabolites were measured using liquid chromatography coupled to mass spectrometry. Metagenome Kyoto Encyclopedia of Genes and Genomes Orthology analysis was performed to investigate the differential functional gene abundance involved in specific metabolic pathways. Data were analyzed according to clinical outcome of remission (W6_rem), no remission (W6_nr), sustained remission (W12_sr), and nonsustained (W12_nsr) remission.

RESULTS

A decrease in kynurenine and succinate synthesis and an increase in N-α-acetyl-arginine characterized CDED+PEN W6_rem, whereas changes in lipid metabolism characterized EEN W6_rem, especially reflected by lower levels in ceramides. In contrast, fecal metabolites in EEN W6_nr were comparable to baseline/W0 samples. CDED+PEN W6_rem children maintained metabolome changes through W12. In contrast, W12_nsr children in the EEN group, who resumed a free diet after week 6, did not. The metabolome of CDED+PEN differed from EEN in the purine, pyrimidine, and sphingolipid pathways. A significant differential abundance in several genes involved in these pathways was detected.

CONCLUSION

CDED+PEN- and EEN-induced remission are associated with significant changes in inflammatory bowel disease-associated metabolites such as kynurenine, ceramides, amino acids, and others. Sustained remission with CDED+PEN, but not EEN, was associated with persistent changes in metabolites.

CLINICALTRIALS

gov, Number NCT01728870.

Denials, Dilly-dallying, and Despair: Navigating the Insurance Labyrinth to Obtain Medically Necessary Medications for Pediatric Inflammatory Bowel Disease Patients

Increasingly, in the United States, the prescribing of high-cost drugs has become a challenge for physicians and other practitioners. Such drugs are highly regulated by third-party payers (aka insurance), as well as pharmacy benefit managers. Not infrequently, a clinician prescribing a medication will have the payment for the prescription denied by the third-party payer, with the end result being a delay in getting a medically necessary medication to a patient. This article highlights the challenges involved in the prior authorization and denial process, with a focus on pediatric inflammatory bowel disease. The article reviews the role of pharmacy benefits managers in restricting access to drugs, and the reasons why denials of medically necessary medications may occur. The article also provides information on how to appeal denials, how to write a letters of medical necessity, and how to conduct a proper peer-to-peer review. Advocacy from patients and clinicians will be important, as we want to reform the process in the future.

The Pediatric Inflammatory Bowel Disease Medical Home: A Proposed Model

Care for patients with inflammatory bowel disease (IBD) can be complex and costly. Care delivery models to address these challenges and improve care quality are essential. The patient-centered medical home (PCMH), which was developed in the primary care setting, has recently been applied successfully to the adult IBD population. Following the tenets of the PCMH, this specialty medical home (SMH) emphasizes team-based care that is accessible, comprehensive, patient/family-centered, coordinated, compassionate, and continuous and has demonstrated improved patient outcomes. Children and young adults with IBD have equally complex care needs, with additional challenges not faced by the adult population such as growth, physical and psychosocial development, and transition of care from pediatric to adult providers. Thus, we advocate that the components of the PCMH are equally-if not more-important in caring for the pediatric patient population. In this article, we review what is known about the application of the PCMH model in adult IBD care, describe care delivery within the Center for Pediatric and Adolescent IBD at Nationwide Children's Hospital as an example of a pediatric IBD medical home, and propose a research agenda to further the development and dissemination of comprehensive care delivery for children and adolescents with IBD.

Pediatric Management of Crohn's Disease

Pediatric Crohn's disease is often more severe, requires higher levels of immunosuppression, and is associated with greater morbidity compared with adult Crohn's disease. Unique considerations in pediatric Crohn's disease include growth impairment, pubertal delay, bone disease, longevity of disease burden, and psychosocial impact. Treatment options are limited, requiring off-label use of therapy in this challenging patient population. Understanding the medications available, the existing evidence supporting their use, and side effects is important. There is tremendous potential for growth and improvement in this field and it is essential that all gastroenterologists have an understanding of this complex and unique patient population.

Efficacy and safety of vedolizumab for pediatrics with inflammatory bowel disease: a systematic review

BACKGROUND

Vedolizumab use in pediatrics is still off-label and the data are limited. We conducted a systematic review evaluating the efficacy and safety of vedolizumab in children and adolescents with inflammatory bowel disease (IBD).

METHODS

PubMed, EMBASE and Cochrane databases were systematically searched for studies of vedolizumab in children and adolescents with IBD reporting clinical remission, response, corticosteroid-free (CS-free) remission, mucosal healing, or safety up to December 3rd 2021.

RESULTS

Ten studies, comprising 455 patients were included. For CD, the pooled clinical remission rates were 25% (19/75) at 6 weeks, 28% (25/85) at 14 weeks, 32% (17/53) at 22 weeks, and 46% (43/92) at 1 year. For UC/IBD-U, the pooled clinical remission rates were 36% (25/70) at 6 weeks, 48% (52/101) at 14 weeks, 53% (24/45) at 22 weeks, and 45% (50/112) at 1 year. Mucosal healing was found in 17%-39% of CD and 15%-34% of UC/IBD-U respectively. Six percent of patients reported serious adverse events.

CONCLUSIONS

According to low-quality evidence based on case series, approximately one-third and one-half of patients for CD and UC/IBD-U respectively achieved remission within 22 weeks, and about half of patients achieved remission at 1 year with reasonable safety profile. Long-term benefit profile data and high quality evidence are still needed.

Impact of Drug Approval Pathways for Paediatric Inflammatory Bowel Disease

BACKGROUND AND AIMS

Timely access to approved medications is a priority in paediatric inflammatory bowel disease [IBD]. To date, the timing of drug studies in paediatric IBD has been suboptimal, with most studies conducted long after approval has been granted for adult IBD. This delay in approval leads to extensive off-label prescribing of medications in children, often without clear guidance on optimal dosing. The European Medicines Agency [EMA] and U.S. Food and Drug Administration [FDA] have implemented drug development frameworks in an attempt to address these challenges. However, access to information on these regulatory pathways in paediatric IBD is limited. We summarised the time from adult to paediatric approval of IBD therapies, outlining the regulatory approval pathway between the EMA and FDA, with the goal of identifying areas for improvement.

METHODS

We reviewed publicly accessible data from the EMA and the FDA to identify therapeutic agents approved over 2005-2021 for paediatric IBD.

RESULTS AND CONCLUSIONS

Five drugs are currently approved for use in the paediatric IBD population, with long interval delays after adult approval. The impact of these drug development processes in paediatric IBD is awaited. Further consideration needs to be given to the age of enrolment along with novel, more efficient trial designs in an effort to improve access for paediatric IBD patients to newer therapies.

Evaluation of exclusive enteral nutrition and corticosteroid induction treatment in new-onset moderate-to-severe luminal paediatric Crohn's disease

To induce remission in luminal paediatric Crohn's disease (CD), the ESPGHAN/ECCO guideline recommends treatment with exclusive enteral nutrition (EEN) or oral corticosteroids. In newly diagnosed moderate-to-severe paediatric CD patients, we determined the proportion of patients in which EEN or corticosteroids induced remission and maintained remission on azathioprine monotherapy. We included patients from the "TISKids" study assigned to the conventional treatment arm. Patients were aged 3-17 years and had new-onset, untreated luminal CD with weighted paediatric CD activity index (wPCDAI) > 40. Induction treatment consisted of EEN or oral corticosteroids; all received azathioprine maintenance treatment from start of treatment. The primary outcome of this study was endoscopic remission defined as a SES-CD score < 3 without treatment escalation at week 10. Secondary outcomes included proportion of patients without treatment escalation at week 52. In total, 27/47 patients received EEN and 20/47 corticosteroids. At baseline, patient demographics and several inflammation parameters were similar between the two treatment groups. At 10 weeks, clinical remission rates were 7/23 (30%) for EEN and 7/19 (37%) for corticosteroids (p = 0.661). Twenty-nine of 47 consented to endoscopy at 10 weeks, showing endoscopic remission rates without treatment escalation in 2/16 (13%) of EEN-treated patients and in 1/13 (8%) of corticosteroid-treated patients (p = 1.00). At week 52, 23/27 (85%) EEN-treated patients received treatment escalation (median 14 weeks) and 13/20 (65%) corticosteroid-treated patients (median 27 weeks), p = 0.070.Conclusion: In children with moderate-to-severe newly diagnosed CD, induction treatment with EEN or CS regularly is insufficient to achieve endoscopic remission without treatment escalation at week 10. Trial registration number: NCT02517684 What is Known: • Endoscopic remission is associated with a low risk of disease progression. • FL-IFX was superior to conventional treatment in achieving and maintaining remission in paediatric patients with moderate-to-severe CD the first year from diagnosis. What is New: • In children with newly diagnosed moderate-to-severe CD, clinical remission rates and endoscopic remission rates without treatment escalation at week 10 were 30% and 13% after EEN and 37% and 8% after corticosteroid induction treatment. • The current treatment target was often not achieved by either EEN or corticosteroid induction treatment after bridging to azathioprine.

A longitudinal model for the Mayo Clinical Score and its sub-components in patients with ulcerative colitis

Clinical trials in patients with ulcerative colitis (UC) face the challenge of high and variable placebo response rates. The Mayo Clinical Score (MCS) is used widely as the primary endpoint in clinical trials to describe the clinical status of patients with UC. The MCS is comprised of four subscores, each scored 0, 1, 2 and 3: rectal bleeding (RB), stool frequency (SF), physician's global assessment (PGA), and endoscopy (ENDO) subscore. Excluding the PGA subscore gives the modified MCS. Quantitative insight on the placebo response, and its impact on the components of the MCS over time, can better inform clinical trial design and interpretation. Longitudinal modeling of the MCS, and the modified MCS, can be challenging due to complex clinical trial design, population heterogeneity, and limited assessments for the ENDO subscore. The current study pooled patient-level placebo/standard of care (SoC) arm data from five clinical trials in the TransCelerate database to develop a longitudinal placebo response model that describes the MCS over time in patients with UC. MCS subscores were modeled using proportional odds models, and the removal of patients from the placebo/SoC arm, or "dropout", was modeled using logistic regression models. The subscore and dropout models were linked to allow for the prediction of the MCS and the modified MCS. Stepwise covariate modeling identified prior exposure to TNF-α antagonists as a statistically significant predictor on the RB + SF subscore. Patients with prior exposure to TNF-α antagonists had higher post-baseline RB + SF subscores than naive patients.

Infliximab Therapy in Very Early Onset Crohn's Disease: Real-World Experience in China

BACKGROUND

Data concerning of the effectiveness of infliximab in very early onset Crohn's disease patients are rare.

AIM

To assess the effectiveness and safety issues of infliximab treatment for this rare cohort.

METHODS

The pediatric Crohn's disease activity index, Crohn's disease endoscopic index score, height, and weight were retrospectively recorded at baseline, week 14, and week 54. The rates of clinical remission and mucosal healing and growth of patients were compared between patients younger and older than 6 years of age. Loss of response or non-response to infliximab and adverse events were assessed during the entire treatment period.

RESULTS

Sixty-five patients were enrolled in the study. Sixty-four percent and 40.0% of very early onset Crohn's disease patients achieved clinical remission and mucosal healing after induction therapy. Adjusted for the covariances, very early disease onset had no association with primary non-response (p = 0.360) or mucosal healing (p = 0.361). Early disease onset was associated with discontinuation of infliximab due to adverse events (hazard ratio [HR] 7.15, 95% CI 1.73-29.51, p = 0.006). Patients < 6 years had lower body mass index for age z score improvement during the induction phase (p = 0.04).

CONCLUSIONS

Very early onset Crohn's disease patients had similar non-response rates and mucosal healing rates as those who were 6 years or older during induction therapy. Greater discontinuation of infliximab due to adverse events was observed in very early onset Crohn's disease patients.

Antibiotics in pediatric inflammatory bowel diseases: a systematic review

Introduction: Current therapies in pediatric Inflammatory Bowel Diseases (IBD) target the immune system and often fail to sustain long-term remission. There is a high need for development of alternative treatment strategies such as antibiotics in pediatric IBD.Areas covered: This study systematically assessed efficacy and safety of antibiotics in pediatric IBD. CENTRAL, EMBASE, and Medline were searched for Randomized Controlled Trials (RCTs). Quality assessment was conducted with the Cochrane risk-of-bias tool.Expert opinion: Two RCTs (n = 101, 4.4-18 years, 43% male) were included. Both studies had overall low risk of bias. In mild-to-moderate Crohn's disease, azithromycin+metronidazole (AZ+MET) (n = 35) compared to metronidazole (MET) alone (n = 38) did not induce a significantly different response (PCDAI drop ≥12.5 or remission) (p = 0.07). For induction of remission (PCDAI≤10), AZ+MET was more effective than MET (p = 0.025). In Acute Severe Colitis, mean 5-day-PUCAI was significantly lower in the antibiotic (vancomycin, amoxicillin, metronidazole, doxycycline)+intravenous-corticosteroids group (AB+IVCS) (n = 16) compared to IVCS alone (n=12) (p = 0.037), whereas remission (PUCAI<10) did not differ (p = 0.61). No significant drug-related adverse events were reported. Results of this systematic review of antibiotic use highlight the lack of evidence in pediatric IBD. More evidence is needed before widespread implementation in daily practice.

Efficacy and safety of adalimumab in paediatric patients with moderate-to-severe ulcerative colitis (ENVISION I): a randomised, controlled, phase 3 study

BACKGROUND

Biologic treatment options are limited for children with ulcerative colitis. The aim of this study was to assess the safety and efficacy of adalimumab in children with moderate-to-severe ulcerative colitis.

METHODS

The double-blind ENVISION I study was done at 24 hospitals in ten countries. Children (4-17 years) with moderate-to-severe ulcerative colitis despite stable doses of concurrent treatment with oral corticosteroids or immunosuppressants were enrolled. Per the original study design, patients were randomly assigned with an Interactive Voice Response System (IVRS) to receive either high-dose induction adalimumab (2·4 mg/kg [maximum 160 mg] at weeks 0 and 1) or standard-dose induction adalimumab (2·4 mg/kg at week 0 and placebo at week 1); both groups received 1·2 mg/kg (maximum 80 mg) at week 2 and 0·6 mg/kg (maximum 40 mg) at weeks 4 and 6. Patients with partial Mayo score (PMS) response at week 8 (defined as a decrease of two or more points and a decrease of ≥30% from baseline in PMS) were randomly assigned (2:2:1)-using IVRS-to receive either high-dose maintenance adalimumab (0·6 mg/kg weekly), standard-dose maintenance adalimumab (0·6 mg/kg every other week), or placebo up to week 52 (random assignment to the placebo group was ceased mid-trial, as was randomisation in the induction phase with all subsequent patients receiving open-label high-dose induction adalimumab). Coprimary endpoints were the proportion of patients with PMS remission at week 8 (intent-to-treat [ITT]-E population, not including those patients who were not randomised in the induction phase) and full Mayo score (FMS) remission at week 52 in week 8 PMS responders (maintenance ITT-E [mITT-E] population), for which the pooled adalimumab group (patients who received high-dose or standard-dose adalimumab) and the individual dose groups were compared against external adult placebo rates. We report results of the final confirmatory analysis. This trial is registered with ClinicalTrials.gov, NCT02065557.

FINDINGS

93 children were recruited between Oct 13, 2014, and Sept 5, 2018, to the main study (77 [83%] were randomly assigned [double-blind] to receive high-dose or standard-dose induction adalimumab; 16 [17%] received open-label high-dose induction adalimumab after study design change). At week 8, 74 (80%) children who were PMS responders continued to the maintenance period. 62 (84%) patients were randomly assigned to receive high-dose or standard-dose maintenance adalimumab treatment; 12 (16%) patients received placebo. In patients in the ITT-E population who were randomly assigned to receive high-dose induction adalimumab, a significantly higher proportion of patients were in PMS remission at week 8 (28 [60%] of 47) compared with external placebo (19·8%; p=0·0001). 13 (43%) of 30 patients in the standard-dose induction adalimumab group were in PMS remission at week 8 versus an external placebo rate of 19·8%, but this difference was not significant (p=0·38). Similarly, FMS remission at week 52 in children who were week 8 PMS responders was reported in a significantly higher proportion of patients in mITT-E population who received high-dose maintenance adalimumab (14 [45%] of 31 patients) versus external placebo at week 52 (18·4%; p=0·0001). Nine (29%) of 31 patients in the standard-dose maintenance adalimumab group were in FMS remission at week 52 versus an external placebo rate of 18·4%, but this difference was not significant (p=0·38). Remission rates in the pooled adalimumab groups were significantly better compared with external placebo (PMS remission at week 8: 41 [53%] of 77 patients; p<0·0001; FMS remission at week 52: 23 [37%] of 62 patients; p=0·0001). 21 (23%) of 93 patients in the main study had one or more treatment-emergent serious adverse events during any adalimumab exposure. The most common adverse events were headache, anaemia, and ulcerative colitis flare during the induction period and ulcerative colitis flare, headache, and nasopharyngitis during the maintenance period.

INTERPRETATION

Clinically meaningful rates of remission and response were reported in children who received adalimumab in this study. No new safety signals were observed, suggesting that adalimumab is an efficacious and safe treatment option for children with moderate-to-severe ulcerative colitis.

FUNDING

AbbVie.

One-year outcomes with ustekinumab therapy in infliximab-refractory paediatric ulcerative colitis: a multicentre prospective study

BACKGROUND

The phase 3 (UNIFI) trial of ustekinumab (anti-interleukin 12/23) demonstrated efficacy even after prior biologic failure in adult ulcerative colitis (UC), but paediatric data are lacking.

AIM

To prospectively monitor efficacy and serum concentrations of ustekinumab given to children with UC refractory to other biologics.

METHODS

Children with anti-TNF refractory UC initiating ustekinumab intravenously at sites of the Canadian Children IBD Network prior to 12/2019 are included. The primary endpoint was steroid-free clinical remission with subcutaneous ustekinumab at 52 weeks (Paediatric Ulcerative Colitis Activity Index <10, no steroids ≥4 weeks). Ustekinumab levels were measured after week 20. Endoscopic improvement was defined as Mayo endoscopic subscore ≤1, or faecal calprotectin (FCP) <250 μg/g if not re-colonoscoped.

RESULTS

At six sites between 01/2018 and 11/2019, 25 children (median [IQR] age 14.8 years [12.3-16.2], 72% female) with UC duration 2.3 years (1.1-4.2) received intravenous ustekinumab (median dose/kg of 6.4 [5.5-7.5] mg). All patients had failed prior infliximab therapy, and 12 (48%) also vedolizumab. Five patients discontinued ustekinumab after IV induction (four undergoing colectomy). On intent to treat basis, 44% achieved the primary endpoint of steroid-free remission at week 52, including nine (69%) of 13 who previously treated with anti-TNF only vs two (17%) of 12 who previously failed also by vedolizumab (P = 0.008). Seven of 11 remitters met the criteria for endoscopic improvement. The median (IQR) trough levels (μg/mL) were greater with q4 vs q8 weekly dosing (8.7 [4.6-9.9] vs 3.8 [12.7-4.8]) P = 0.02, but greater exposure was not associated with a superior rate of clinical remission. No adverse events were associated with therapy.

CONCLUSION

Ustekinumab demonstrated efficacy in this paediatric cohort with otherwise treatment-refractory UC. Treatment failure was not due to inadequate drug exposure.

Dietary Management in Pediatric Patients with Crohn's Disease

It has been widely endorsed that a multifactorial etiology, including interaction between genetic and environmental factors, can contribute to Crohn's Disease (CD) pathogenesis. More specifically, diet has proven to be able to shape gut microbiota composition and thus is suspected to play a significant role in inflammatory bowel disease (IBD) pathogenesis. Moreover, poor nutritional status and growth retardation, arising from several factors such as reduced dietary intake or nutrient leakage from the gastrointestinal tract, represent the hallmarks of pediatric CD. For these reasons, multiple research lines have recently focused on the utilization of dietary therapies for the management of CD, aiming to target concurrently mucosal inflammation, intestinal dysbiosis and optimization of nutritional status. The forerunner of such interventions is represented by exclusive enteral nutrition (EEN), a robustly supported nutritional therapy; however, it is burdened by monotony and low tolerance in the long term. Novel dietary interventions, such as Crohn's Disease Exclusion Diet or Crohn's Disease treatment with eating, have shown their efficacy in the induction of remission in pediatric patients with CD. The aim of the present narrative review is to provide a synopsis of the available nutritional strategies in the management of pediatric CD and to discuss their application in the dietary management of these patients.

Nutritional Therapy Strategies in Pediatric Crohn's Disease

The increase in incidences of pediatric Crohn's Disease (CD) worldwide has been strongly linked with dietary shifts towards a Westernized diet, ultimately leading to altered gut microbiota and disturbance in intestinal immunity and the metabolome. Multiple clinical studies in children with CD have demonstrated the high efficacy of nutritional therapy with exclusive enteral nutrition (EEN) to induce remission with an excellent safety profile. However, EEN is poorly tolerated, limiting its compliance and clinical application. This has spiked an interest in the development of alternative and better-tolerated nutritional therapy strategies. Several nutritional therapies have now been designed not only to treat the nutritional deficiencies seen in children with active CD but also to correct dysbiosis and reduce intestinal inflammation. In this review, we report the most recent insights regarding nutritional strategies in children with active CD: EEN, partial enteral nutrition (PEN), Crohn's disease exclusive diet (CDED), and CD treatment-with-eating diet (CD-TREAT). We describe their setup, efficacy, safety, and (dis)advantages as well as some of their potential mechanisms of action and perspectives. A better understanding of different nutritional therapeutic options and their mechanisms will yield better and safer management strategies for children with CD and may address the barriers and limitations of current strategies in children.

Ulcerative Colitis-Diagnostic and Therapeutic Algorithms

BACKGROUND

Ulcerative colitis is a chronic inflammatory bowel disease with an estimated 150 000 patients in Germany alone.

METHODS

This review is based on publications about current diagnostic and therapeutic strategies for ulcerative colitis that were retrieved by a selective search in PubMed, and on current guidelines.

RESULTS

The primary goal of treatment is endoscopically confirmed healing of the mucosa. Mesalamine, in various forms of administration, remains the standard treatment for uncomplicated ulcerative colitis. Its superiority over placebo has been confirmed in meta-analyses of randomized, controlled trials. Glucocorticoids are highly effective in the acute treatment of ulcerative colitis, but they should only be used over the short term, because of their marked side effects. Further drugs are available to treat patients with a more complicated disease course of ulcerative colitis, including azathioprine, biological agents, JAK inhibitors (among them TNF antibodies, biosimilars, ustekinumab, vedolizumab, and tofacitinib), and calcineurin inhibitors. Proctocolectomy should be considered in refractory cases, or in the presence of high-grade epithelial dysplasia. Ulcerative colitis beginning in childhood or adolescence is often characterized by rapid progression and frequent comorbidities that make its treatment a special challenge.

CONCLUSION

A wide variety of drugs are now available for the treatment of ulcerative colitis, enabling the individualized choice of the best treatment for each patient. Regular surveillance colonoscopies to rule out colon carcinoma should be scheduled at intervals that depend on risk stratification.

Developmental Pharmacodynamics and Modeling in Pediatric Drug Development

Challenges in pediatric drug development include small patient numbers, limited outcomes research, ethical barriers, and sparse biosamples. Increasingly, pediatric drug development is focusing on extrapolation: leveraging knowledge about adult disease and drug responses to inform projections of drug and clinical trial performance in pediatric subpopulations. Pharmacokinetic-pharmacodynamic (PK-PD) modeling and extrapolation aim to reduce the numbers of patients and data points needed to establish efficacy. Planning for PK-PD and biomarker studies should begin early in the adult drug development program. Extrapolation relies on the assumption that both the underlying disease and the mechanism of action of the drug used to treat that disease are similar in adults and pediatric subpopulations. Clearly, developmental changes in PK and PD need to be considered to enhance the quality of PK-PD modeling and, therefore, increase the success of extrapolation. This article focuses on the influence of differences in PD between adults and pediatric subpopulations that are highly relevant for the use of extrapolation.

Protocol for a multinational risk-stratified randomised controlled trial in paediatric Crohn's disease: methotrexate versus azathioprine or adalimumab for maintaining remission in patients at low or high risk for aggressive disease course

INTRODUCTION

Immunomodulators such as thiopurines (azathioprine (AZA)/6-mercaptopurine (6MP)), methotrexate (MTX) and biologics such as adalimumab (ADA) are well established for maintenance of remission within paediatric Crohn's disease (CD). It remains unclear, however, which maintenance medication should be used first line in specific patient groups.

AIMS

To compare the efficacy of maintenance therapies in newly diagnosed CD based on stratification into high and low-risk groups for severe CD evolution; MTX versus AZA/6MP in low-risk and MTX versus ADA in high-risk patients. Primary end point: sustained remission at 12 months (weighted paediatric CD activity index ≤12.5 and C reactive protein ≤1.5 fold upper limit) without relapse or ongoing requirement for exclusive enteral nutrition (EEN)/steroids 12 weeks after treatment initiation.

METHODS AND ANALYSIS

REDUCE-RISK in CD is an international multicentre open-label prospective randomised controlled trial funded by EU within the Horizon2020 framework (grant number 668023). Eligible patients (aged 6-17 years, new-onset disease receiving steroids or EEN for induction of remission for luminal ± perianal CD are stratified into low and high-risk groups based on phenotype and response to induction therapy. Participants are randomised to one of two treatment arms within their risk group: low-risk patients to weekly subcutaneous MTX or daily oral AZA/6MP, and high-risk patients to weekly subcutaneous MTX or fortnightly ADA. Patients are followed up for 12 months at prespecified intervals. Electronic case report forms are completed prospectively. The study aims to recruit 312 participants (176 low risk; 136 high risk).

ETHICS AND DISSEMINATION

ClinicalTrials.gov Identifier: (NCT02852694), authorisation and approval from local ethics committees have been obtained prior to recruitment. Individual informed consent will be obtained prior to participation in the study. Results will be published in a peer-reviewed journal with open access.

TRIAL REGISTRATION NUMBER

NCT02852694; Pre-results.