Explorative study on the value of hepcidin in predicting iron non-responsiveness in paediatric inflammatory bowel disease.

BACKGROUND: In a considerable proportion of anaemic children with inflammatory bowel disease (IBD), haemoglobin (Hb) does not normalise after iron therapy. We evaluated the added value of novel iron markers (hepcidin and soluble transferrin receptor [sTfR]) as compared to traditional iron markers (ferritin and transferrin saturation [TSAT]) to determine the best strategy for the prediction of non-responsiveness to iron suppletion. METHODS: In this secondary analysis of prospectively collected data, we measured iron markers in anaemic children (Hb Z-score < -2.0) with IBD at baseline and one month after the initiation of iron therapy. Non-responsiveness was defined as an increase in Hb Z-score of less than 1 within a month. Logistic regression analysis was used to construct multi-biomarker prognostic models. RESULTS: Of 40 anaemic paediatric IBD patients, sixteen (40%) were non-responsive to iron therapy after one month. Hb Z-score and hepcidin Z-score had the highest predictive ability (area under the ROC curve [AUROC] 0.80) providing sensitivity of 69% and specificity 92%. In a post-hoc analysis we defined hepcidin cut-off values to predict iron non-responsiveness. CONCLUSION: A diagnostic strategy that involves baseline Hb Z-score and hepcidin Z-score in anaemic children with IBD reliably identifies those who will not respond to iron therapy. IMPACT: Non-response to oral and intravenous iron suppletion therapy is high in paediatric IBD and should be identified early. Prediction models using baseline hepcidin demonstrated higher sensitivity and specificity to predict iron non-response compared to models using baseline traditional iron indicators (ferritin and transferrin saturation). In a post hoc analysis, we defined cut-off values for hepcidin to facilitate the correct timing of iron treatment in young anaemic patients with chronic inflammatory bowel disease.

Systematic review: Patient-related, microbial, surgical, and histopathological risk factors for endoscopic post-operative recurrence in patients with Crohn's disease.

BACKGROUND: Risk stratification for endoscopic post-operative recurrence (ePOR) in Crohn's disease (CD) is required to identify patients who would benefit most from initiation of prophylactic medication and intensive monitoring of recurrence. AIMS: To assess the current evidence on patient-related, microbial, surgical and histopathological risk factors for ePOR in patients with CD after ileocolic (re-)resection. METHODS: Multiple online databases (Embase, MEDLINE, Web of Science and Cochrane Library) were searched up to March 2024. Studies with reported associations of patient-related, microbial, surgical and/or histopathological factors for ePOR (i.e., Rutgeerts' score ≥i2 or modified Rutgeerts' score ≥i2a) were included. The risk of bias was assessed with the Newcastle-Ottawa Scale for observational cohort studies and case-control studies. RESULTS: In total, 47 studies were included (four RCTs, 29 cohort studies, 12 case-control studies, one cross-sectional study and one individual participant data meta-analysis) including 6006 patients (median sample size 87 patients [interquartile range 46-170]). Risk of bias assessment revealed a poor quality in 41% of the studies. An association was reported in multiple studies of ePOR with active smoking at and post-surgery, male sex and prior bowel resection. A heterogeneous association with ePOR was reported for other risk factors included in the current guidelines (penetrating disease, perianal disease, younger age, extensive small bowel disease and presence of granulomas in the resection specimen or myenteric plexitis in the resection margin), and other patient-related, microbial, surgical and histopathological factors. CONCLUSION: Risk factors for ePOR in international guidelines are not consistently reported as risk factors in current literature except for active smoking and prior bowel resection. To develop evidence-based, personalised strategies, large prospective studies are warranted to identify risk factors for ePOR. Validation studies of promising (bio)markers are also required.

A Prediction Model for Successful Increase of Adalimumab Dose Intervals in Patients with Crohn's Disease: Secondary Analysis of the Pragmatic Open-Label Randomised Controlled Non-inferiority LADI Trial.

BACKGROUND: In the pragmatic open-label randomised controlled non-inferiority LADI trial we showed that increasing adalimumab (ADA) dose intervals was non-inferior to conventional dosing for persistent flares in patients with Crohn's disease (CD) in clinical and biochemical remission. AIMS: To develop a prediction model to identify patients who can successfully increase their ADA dose interval based on secondary analysis of trial data. METHODS: Patients in the intervention group of the LADI trial increased ADA intervals to 3 and then to 4 weeks. The dose interval increase was defined as successful when patients had no persistent flare (> 8 weeks), no intervention-related severe adverse events, no rescue medication use during the study, and were on an increased dose interval while in clinical and biochemical remission at week 48. Prediction models were based on logistic regression with relaxed LASSO. Models were internally validated using bootstrap optimism correction. RESULTS: We included 109 patients, of which 60.6% successfully increased their dose interval. Patients that were active smokers (odds ratio [OR] 0.90), had previous CD-related intra-abdominal surgeries (OR 0.85), proximal small bowel disease (OR 0.92), an increased Harvey-Bradshaw Index (OR 0.99) or increased faecal calprotectin (OR 0.997) were less likely to successfully increase their dose interval. The model had fair discriminative ability (AUC = 0.63) and net benefit analysis showed that the model could be used to select patients who could increase their dose interval. CONCLUSION: The final prediction model seems promising to select patients who could successfully increase their ADA dose interval. The model should be validated externally before it may be applied in clinical practice. CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov, number NCT03172377.

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.

Defining Comprehensive Disease Control for Use as a Treatment Target for Ulcerative Colitis in Clinical Practice: International Delphi Consensus Recommendations.

BACKGROUND AND AIMS: Treatment of ulcerative colitis [UC] requires a patient-centric definition of comprehensive disease control that considers improvements in aspects not typically captured by classical landmark trial endpoints. In an international initiative, we reviewed aspects of UC that affect patients and/or indicate mucosal inflammation, to achieve consensus on which aspects to combine in a definition of comprehensive disease control, using a modified Delphi process. METHODS: The Delphi panel comprised 12 gastroenterologists and one patient advocate. Two gastroenterologists were elected as chairs and did not vote. To inform statements, we asked 18 patients and the panel members about their experiences of remission and reviewed published literature. Panel members voted on statements anonymously in three rounds, with a live discussion before Round 3. Consensus was met if ≥67% of the panel agreed. Statements without consensus in Rounds 1 and 2 were revised or discarded after Round 3. RESULTS: The panel agreed to measure individual patient benefit using a definition of comprehensive disease control that combines aspects currently measured in trials [rectal bleeding, stool frequency, disease-related quality of life, endoscopy, histological inflammatory activity, inflammatory biomarkers, and corticosteroid use] with additional patient-reported symptoms [bowel urgency, abdominal pain, extraintestinal manifestations, fatigue, and sleep disturbance]. The panel agreed on scoring systems and thresholds for many aspects. CONCLUSIONS: Using a robust methodology, we defined comprehensive disease control in UC. Next, we will combine the measurement and scoring of these aspects into a multicomponent tool and will adopt comprehensive disease control as a treatment target in clinical practice and trials.

Cost-Effectiveness Analysis of Increased Adalimumab Dose Intervals in Crohn's Disease Patients in Stable Remission: The Randomized Controlled LADI Trial.

BACKGROUND AND AIMS: We aimed to assess cost-effectiveness of increasing adalimumab dose intervals compared to the conventional dosing interval in patients with Crohn's disease [CD] in stable clinical and biochemical remission. DESIGN: We conducted a pragmatic, open-label, randomized controlled non-inferiority trial, comparing increased adalimumab intervals with the 2-weekly interval in adult CD patients in clinical remission. Quality of life was measured with the EQ-5D-5L. Costs were measured from a societal perspective. Results are shown as differences and incremental net monetary benefit [iNMB] at relevant willingness to accept [WTA] levels. RESULTS: We randomized 174 patients to the intervention [n = 113] and control [n = 61] groups. No difference was found in utility (difference: -0.017, 95% confidence interval [-0.044; 0.004]) and total costs (-€943, [-€2226; €1367]) over the 48-week study period between the two groups. Medication costs per patient were lower (-€2545, [-€2780; -€2192]) in the intervention group, but non-medication healthcare (+€474, [+€149; +€952]) and patient costs (+€365 [+€92; €1058]) were higher. Cost-utility analysis showed that the iNMB was €594 [-€2099; €2050], €69 [-€2908; €1965] and -€455 [-€4,096; €1984] at WTA levels of €20 000, €50 000 and €80 000, respectively. Increasing adalimumab dose intervals was more likely to be cost-effective at WTA levels below €53 960 per quality-adjusted life year. Above €53 960 continuing the conventional dose interval was more likely to be cost-effective. CONCLUSION: When the loss of a quality-adjusted life year is valued at less than €53 960, increasing the adalimumab dose interval is a cost-effective strategy in CD patients in stable clinical and biochemical remission. CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov, number NCT03172377.

The cost of inflammatory bowel disease in high-income settings: a Lancet Gastroenterology & Hepatology Commission.

The cost of caring for patients with inflammatory bowel disease (IBD) continues to increase worldwide. The cause is not only a steady increase in the prevalence of Crohn's disease and ulcerative colitis in both developed and newly industrialised countries, but also the chronic nature of the diseases, the need for long-term, often expensive treatments, the use of more intensive disease monitoring strategies, and the effect of the diseases on economic productivity. This Commission draws together a wide range of expertise to discuss the current costs of IBD care, the drivers of increasing costs, and how to deliver affordable care for IBD in the future. The key conclusions are that (1) increases in health-care costs must be evaluated against improved disease management and reductions in indirect costs, and (2) that overarching systems for data interoperability, registries, and big data approaches must be established for continuous assessment of effectiveness, costs, and the cost-effectiveness of care. International collaborations should be sought out to evaluate novel models of care (eg, value-based health care, including integrated health care, and participatory health-care models), as well as to improve the education and training of clinicians, patients, and policy makers.

Ustekinumab Trough Concentrations Are Associated with Biochemical Outcomes in Patients with Crohn's Disease.

OBJECTIVE: It is unknown whether ustekinumab (UST) levels can predict clinical outcomes in Crohn's disease (CD) patients. We assessed the exposure-response relationship of UST trough concentrations with biochemical outcomes at week 24 in a prospective, real-world setting. METHODS: We performed a prospective study in patients with CD starting UST in four academic centres in the Netherlands. All patients received a weight-adjusted intravenous (IV) UST induction dose, followed by one subcutaneous (SC) dose of 90 mg UST at 8 weeks. Maintenance therapy consisted of 90 mg subcutaneous UST every 8 or 12 weeks. Individual UST concentration time course during treatment were estimated using a population pharmacokinetic (PK) model. Quartile analysis and logistic regression were performed to analyse if UST concentrations at week 8 were associated with biochemical remission rates at week 24 (C-reactive protein (CRP) ≤ 5 mg/L and / or faecal calprotectin (FC) ≤ 250 mg/kg). RESULTS: In total, 124 patients with CD were included. Patients achieving biochemical remission at week 12 and 24 had significantly higher UST levels at week 8 compared to patients without biochemical remission (6.6 µg/mL versus 3.9 µg/mL, P < 0.01 and 6.3 µg/mL versus 3.9 µg/mL, P < 0.01, respectively). In quartile analysis, patients with UST levels in the highest quartile (≥ 6.3 µg/mL at week 8) had higher biochemical remission rates at week 12 and week 24. There was no association between UST levels at and corticosteroid-free clinical remission rates. CONCLUSION: In this real-world cohort of patients with CD, UST levels in the highest quartile (≥ 6.3 µg/mL) at week 8 were associated with higher biochemical remission rates at week 24.

Increased versus conventional adalimumab dose interval for patients with Crohn's disease in stable remission (LADI): a pragmatic, open-label, non-inferiority, randomised controlled trial.

BACKGROUND: Despite its effectiveness in treating Crohn's disease, adalimumab is associated with an increased risk of infections and high health-care costs. We aimed to assess clinical outcomes of increased adalimumab dose intervals versus conventional dosing in patients with Crohn's disease in stable remission. METHODS: The LADI study was a pragmatic, open-label, multicentre, non-inferiority, parallel, randomised controlled trial, done in six academic hospitals and 14 general hospitals in the Netherlands. Adults (aged ≥18 years) diagnosed with luminal Crohn's disease (with or without concomitant perianal disease) were eligible when in steroid-free clinical and biochemical remission (defined as Harvey-Bradshaw Index [HBI] score <5, faecal calprotectin <150 µg/g, and C-reactive protein <10 mg/L) for at least 9 months on a stable dose of 40 mg subcutaneous adalimumab every 2 weeks. Patients were randomly assigned (2:1) to the intervention group or control group by the coordinating investigator using a secure web-based system with variable block randomisation (block sizes of 6, 9, and 12). Randomisation was stratified on concomitant use of thiopurines and methotrexate. Patients and health-care providers were not masked to group assignment. Patients allocated to the intervention group increased adalimumab dose intervals to 40 mg every 3 weeks at baseline and further to every 4 weeks if they remained in clinical and biochemical remission at week 24. Patients in the control group continued their 2-weekly dose interval. The primary outcome was the cumulative incidence of persistent flares at week 48 defined as the presence of at least two of the following criteria: HBI score of 5 or more, C-reactive protein 10 mg/L or more, and faecal calprotectin more than 250 µg/g for more than 8 weeks and a concurrent decrease in the adalimumab dose interval or start of escape medication. The non-inferiority margin was 15% on a risk difference scale. All analyses were done in the intention-to-treat and per-protocol populations. This trial was registered at ClinicalTrials.gov, NCT03172377, and is not recruiting. FINDINGS: Between May 3, 2017, and July 6, 2020, 174 patients were randomly assigned to the intervention group (n=113) or the control group (n=61). Four patients from the intervention group and one patient from the control group were excluded from the analysis for not meeting inclusion criteria. 85 (50%) of 169 participants were female and 84 (50%) were male. At week 48, the cumulative incidence of persistent flares in the intervention group (three [3%] of 109) was non-inferior compared with the control group (zero; pooled adjusted risk difference 1·86% [90% CI -0·35 to 4·07). Seven serious adverse events occurred, all in the intervention group, of which two (both patients with intestinal obstruction) were possibly related to the intervention. Per 100 person-years, 168·35 total adverse events, 59·99 infection-related adverse events, and 42·57 gastrointestinal adverse events occurred in the intervention group versus 134·67, 75·03, and 5·77 in the control group, respectively. INTERPRETATION: The individual benefit of increasing adalimumab dose intervals versus the risk of disease recurrence is a trade-off that should take patient preferences regarding medication and the risk of a flare into account. FUNDING: Netherlands Organisation for Health Research and Development.

Superior Effectiveness of Tofacitinib Compared to Vedolizumab in Anti-TNF-experienced Ulcerative Colitis Patients: A Nationwide Dutch Registry Study.

BACKGROUND & AIMS: Clinicians face difficulty in when and in what order to position biologics and Janus kinase inhibitors in patients with anti-tumor necrosis factor-alpha (TNF) refractory ulcerative colitis (UC). We aimed to compare the effectiveness and safety of vedolizumab and tofacitinib in anti-TNF-exposed patients with UC in our prospective nationwide Initiative on Crohn and Colitis Registry. METHODS: Patients with UC who failed anti-TNF treatment and initiated vedolizumab or tofacitinib treatment were identified in the Initiative on Crohn and Colitis Registry in the Netherlands. We selected patients with both clinical as well as biochemical or endoscopic disease activity at initiation of therapy. Patients previously treated with vedolizumab or tofacitinib were excluded. Corticosteroid-free clinical remission (Simple Clinical Colitis Activity Index ≤2), biochemical remission (C-reactive protein ≤5 mg/L or fecal calprotectin ≤250 µg/g), and safety outcomes were compared after 52 weeks of treatment. Inverse propensity score-weighted comparison was used to adjust for confounding and selection bias. RESULTS: Overall, 83 vedolizumab- and 65 tofacitinib-treated patients were included. Propensity score-weighted analysis showed that tofacitinib-treated patients were more likely to achieve corticosteroid-free clinical remission and biochemical remission at weeks 12, 24, and 52 compared with vedolizumab-treated patients (odds ratio [OR], 6.33; 95% confidence interval [CI], 3.81-10.50; P < .01; OR, 3.02; 95% CI, 1.89-4.84; P < .01; and OR, 1.86; 95% CI, 1.15-2.99; P = .01; and OR, 3.27; 95% CI, 1.96-5.45; P < .01; OR, 1.87; 95% CI, 1.14-3.07; P = .01; and OR, 1.81; 95% CI, 1.06-3.09; P = .03, respectively). There was no difference in infection rate or severe adverse events. CONCLUSIONS: Tofacitinib was associated with superior effectiveness outcomes compared with vedolizumab in anti-TNF-experienced patients with UC along with comparable safety outcomes.

Effectiveness and safety of tofacitinib for ulcerative colitis: two-year results of the ICC Registry.

BACKGROUND: Tofacitinib is an oral Janus kinase (JAK) inhibitor and is registered for the treatment of ulcerative colitis (UC). The effectiveness of tofacitinib has been evaluated up to 12 months of treatment. AIM: The aim of this study was to assess the effectiveness and safety of 24 months of tofacitinib use in UC patients in the Netherlands. METHODS: Patients initiating tofacitinib treatment were included in the ICC Registry, a nationwide, observational registry. Patients were prospectively evaluated for up to 24 months. The primary outcome was corticosteroid-free clinical remission (CSFR, Simple Clinical Colitis Activity Index [SCCAI] ≤2) at week 104. Secondary outcomes included biochemical remission (C-reactive protein (CRP) ≤5 mg/L and faecal calprotectin (FC) ≤250 µg/g), safety, and discontinuation rate. RESULTS: We included 110 patients of whom 104 (94.5%) were anti-TNF experienced. After 104 weeks of tofacitinib, 31.8% (34/107) were in CSFR, 23.4% (25/107) in biochemical remission and 18.7% (20/107) in combined clinical and biochemical remission. Of the patients in CSFR at week 52, 76.5% (26/34) remained so after 104 weeks of treatment. Sixty-one patients (55.5%) discontinued tofacitinib after a median duration of 13 weeks (IQR 7-34). The main reasons for discontinuation were non-response (59%), loss of response (14.8%), and adverse events (18%). There were 33.9 possible tofacitinib-related adverse events per 100 patient-years during follow-up. Adverse events most probably related to tofacitinib were skin reactions and headaches. There were 6.4 herpes zoster infections per 100 patient-years. CONCLUSION: Tofacitinib was effective in 31.8% of patients after 24 months of treatment.

Classic drugs in the time of new drugs: real-world, long-term outcomes of thiopurine monotherapy in 1016 patients with inflammatory bowel disease.

BACKGROUND: Thiopurines remain recommended as maintenance therapy in patients with inflammatory bowel disease (IBD). Despite their widespread use, long-term effectiveness data are sparse and safety is an increasingly debated topic which thwarts proper delineation in the current IBD treatment algorithm. AIMS: To document effectiveness and safety of thiopurine monotherapy in patients with IBD, using the population-based IBD South-Limburg (IBDSL) cohort METHODS: All patients starting thiopurine monotherapy as maintenance between 1991 and 2014 were included. Therapy was defined as effective if there was no escalation to biologicals, no course of corticosteroids, no surgery and no hospitalisation for active disease during treatment. Long-term effectiveness was assessed by adjusting for differences in follow-up using Kaplan-Meier analyses. Mid- to long-term safety regarding cancer incidence and clinically relevant liver disease was documented. RESULTS: In total, 1016 patients (643 Crohn's disease [CD]; 373 ulcerative colitis [UC]) received thiopurine monotherapy at a median of 15.2 (Q1-Q3 4.2-48.5) months after diagnosis. During follow-up, effectiveness rates at 1, 5 and 10 years were 64%, 45%, 32%, respectively, in CD and and 66%, 41%, 36%, respectively in UC. No statistically significant differences in effectiveness were observed after stratification for era of initiation (pre-biological vs biological, CD: p = 0.56; UC: p = 0.43). Sixteen non-melanoma skin cancers (incidence rate [IR] 3.33/1000 PY), five lymphomas (IR 1.04/1000 PY) and one urinary tract cancer (IR 0.21/1000 PY) were recorded. Two cases of portal hypertension were identified. CONCLUSION: In real-world practice, thiopurine monotherapy remains effective, safe and durable for patients with CD or UC, including in the era of biologics.

Prediction of Inflammatory Bowel Disease Course Based on Fecal Scent.

The early prediction of changes in disease state allows timely treatment of patients with inflammatory bowel disease (IBD) to be performed, which improves disease outcome. The aim of this pilot study is to explore the potential of fecal volatile organic compound (VOC) profiles to predict disease course. In this prospective cohort, IBD patients were asked to collect two fecal samples and fill in a questionnaire at set intervals. Biochemically, active disease was defined by FCP ≥ 250 mg/g and remission was defined by FCP < 100 mg/g. Clinically, active disease was defined by a Harvey Bradshaw Index (HBI) ≥ 5 for Crohn's disease or by a Simple Clinical Colitis Activity Index (SCCAI) ≥ 3 for ulcerative colitis. Clinical remission was defined by an HBI < 4 or SCCAI ≤ 2. Fecal VOC profiles were measured using gas chromatography-ion mobility spectrometry (GC-IMS). The fecal samples collected first were included for VOC analysis to predict disease state at the following collection. A total of 182 subsequently collected samples met the disease-state criteria. The fecal VOC profiles of samples displaying low FCP levels at the first measurements differed between patients preceding exacerbation versus those who remained in remission (AUC 0.75; p < 0.01). Samples with FCP levels at the first time point displayed different VOC profiles in patients preceding remission compared with those whose disease remained active (AUC 0.86; p < 0.01). Based on disease activity scores, there were no significant differences in any of the comparisons. Alterations in fecal VOC profiles preceding changes in FCP levels may be useful to detect disease-course alterations at an early stage. This could lead to earlier treatment, decreased numbers of complications, surgery and hospital admission.

Re-induction with intravenous Ustekinumab after secondary loss of response is a valid optimization strategy in Crohn's disease.

BACKGROUND AND AIM: Re-induction with intravenous ustekinumab after secondary loss of response in Crohn's disease is a relatively new strategy to regain efficacy. This real-world cohort study aimed to evaluate its effectiveness and safety. METHODS: Crohn's disease patients with loss of response after initial response to ustekinumab and treated with a second intravenous dose of ustekinumab were included. Clinical, biochemical and endoscopic data were collected. Primary outcome was drug survival. Secondary effectiveness outcomes included clinical remission, primary nonresponse and adverse events. RESULTS: In total, 31 Crohn's disease patients were included after re-induction with intravenous ustekinumab. All patients had failed prior biologic therapy, that is 77% were exposed to two or more antitumor necrosis factor agents and 65% were exposed to vedolizumab prior to initiation of ustekinumab treatment. Median treatment duration between initial treatment and re-induction with intravenous ustekinumab was 11.1 months (interquartile range 6.9-19.5). Ustekinumab therapy after a second dose of intravenous ustekinumab was maintained in 74 and 71% of the patients at weeks 20 and 52. Clinical remission rates after re-induction at weeks 8, 20 and 52 were 37, 56 and 45%, respectively. Nonresponse occurred in 16% of the patients. Adverse events were reported in four patients. CONCLUSIONS: Re-induction with intravenous ustekinumab after secondary loss of response results in continuation of ustekinumab treatment for at least 1 year in almost three-quarters of patients and in clinical remission in half of patients after 1 year. Therefore, ustekinumab re-induction may be considered an important rescue treatment option in patients with refractory Crohn's disease.

Inter-kingdom relationships in Crohn's disease explored using a multi-omics approach.

The etiology of Crohn's disease (CD) is multifactorial. Bacterial and fungal microbiota are involved in the onset and/or progression of the disease. A bacterial dysbiosis in CD patients is accepted; however, less is known about the mycobiome and the relationships between the two communities. We investigated the interkingdom relationships, their metabolic consequences, and the changes in the fungal community during relapse and remission in CD.Two cohorts were evaluated: a British cohort (n = 63) comprising CD and ulcerative colitis patients, and controls. The fungal and bacterial communities of biopsy and fecal samples were analyzed, with the fecal volatiles; datasets were also integrated; and a Dutch cohort (n = 41) comprising CD patients and healthy controls was analyzed for stability of the gut mycobiome.A dysbiosis of the bacterial community was observed in biopsies and stool. Results suggest Bacteroides is likely key in CD and may modulate Candida colonization. A dysbiosis of the fungal community was observed only in the Dutch cohort; Malassezia and Candida were increased in patients taking immunosuppressants. Longitudinal analysis showed an increase in Cyberlindnera in relapse. Saccharomyces was dominant in all fecal samples, but not in biopsies, some of which did not yield fungal reads; amino acid degradation was the main metabolic change associated with CD and both bacteria and fungi might be implicated.We have shown that Bacteroides and yeasts may play a role in CD; understanding their role and relationship in the disease would shed new light on the development and treatment of CD.

Treatment of severe acute ulcerative colitis in SARS-CoV-2 infected patients: report of three cases and discussion of treatment options.

In the wake of the coronavirus disease 2019 (COVID-19) pandemic, it is unclear how asymptomatic severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-infected patients who present with acute severe ulcerative colitis (UC) can be treated effectively and safely. Standard treatment regimens consist of steroids, immunomodulatory drugs, and biological therapies, but therapeutic decision-making becomes challenging as there are uncertainties about how to deal with these drugs in patients with COVID-19 and active UC. Importantly, guidelines for this particular group of patients with UC are still lacking. To inform therapeutic decision-making, we describe three consecutive cases of patients with active UC and COVID-19 and discuss their treatments based on theoretical knowledge, currently available evidence and clinical observations. Three patients were identified through our national inflammatory bowel disease network [Initiative on Crohn's and Colitis (ICC)] for whom diagnosis of SARS-CoV-2-infection was established by reverse transcription-polymerase chain reaction (RT-PCR) testing in nasopharynx, stools, and/or biopsies. Acute severe UC was diagnosed by clinical parameters, endoscopy, and histopathology. Clinical guidelines for SARS-CoV-2-negative patients advocate the use of steroids, calcineurin inhibitors, or tumor necrosis factor alpha (TNF-α)-antagonists as induction therapy, and experiences from the current three cases show that steroids and TNF-α-antagonists could also be used in patients with COVID-19. This could potentially be followed by TNF-α-antagonists, vedolizumab, or ustekinumab as maintenance therapy in these patients. Future research is warranted to investigate if, and which, immunomodulatory drugs should be used for COVID-19 patients that present with active UC. To answer this question, it is of utmost importance that future cases of patients with UC and COVID-19 are documented carefully in international registries, such as the SECURE-IBD registry.

Ustekinuma b for Crohn's Disease: Two-Year Results of the Initiative on Crohn and Colitis (ICC) Registry, a Nationwide Prospective Observational Cohort Study.

AIMS: Ustekinumab is a monoclonal antibody that selectively targets p40, a shared subunit of the cytokines interleukin [IL]-12 and IL-23. It is registered for the treatment of inflammatory bowel diseases. We assessed the 2-year effectiveness and safety of ustekinumab in a real world, prospective cohort of patients with Crohn's disease [CD]. METHODS: Patients who started ustekinumab were prospectively enrolled in the nationwide Initiative on Crohn and Colitis [ICC] Registry. At weeks 0, 12, 24, 52 and 104, clinical remission Harvey Bradshaw Index≤ 4 points], biochemical remission (faecal calprotectin ≤ 200 µg/g and/or C-reactive protein ≤5 mg/L], perianal fistula remission, extra-intestinal manifestations, ustekinumab dosage and safety outcomes were determined. The primary outcome was corticosteroid-free clinical remission at week 104. RESULTS: In total, 252 CD patients with at least 2 years of follow-up were included. Of all included patients, the proportion of patients in corticosteroid-free clinical remission was 32.3% [81/251], 41.4% [104/251], 39% [97/249] and 34.0% [84/247] at weeks 12, 24, 52 and 104, respectively. In patients with combined clinical and biochemical disease activity at baseline [n = 122], the corticosteroid-free clinical remission rates were 23.8% [29/122], 35.2% [43/122], 40.0% [48/120] and 32.8% [39/119] at weeks 12, 24, 52 and 104, respectively. The probability of remaining on ustekinumab treatment after 52 and 104 weeks in all patients was 64.3% and 54.8%, respectively. The main reason for discontinuing treatment after 52 weeks was loss of response [66.7%]. No new safety issues were observed. CONCLUSION: After 104 weeks of ustekinumab treatment, one-third of CD patients were in corticosteroid-free clinical remission.

Corticosteroid enhances epithelial barrier function in intestinal organoids derived from patients with Crohn's disease.

Corticosteroids (CS), first-line therapeutics for Crohn's disease (CD) with moderate or severe disease activity, were found to restore intestinal permeability in CD patients, whereas the underlying molecular events are still largely unknown. This study aimed to investigate the effect and mechanisms of CS prednisolone on epithelial barrier using CD patient-derived intestinal organoids. 3D intestinal organoids were generated from colon biopsies of inactive CD patients. To mimic the inflammatory microenvironment, a mixture of cytokines containing TNF-α, IFN-γ, and IL-1ß were added to the organoid culture with or without pre-incubation of prednisolone or mifepristone. Epithelial permeability of the organoids was assessed by FITC-D4 flux from the basal to luminal compartment using confocal microscopy. Expression of junctional components were analyzed by qRT-PCR, immunofluorescence staining, and western blot. Activity of signaling pathways were analyzed using western blot. Exposure of the cytokines significantly disrupted epithelial barrier of the intestinal organoids, which was partially restored by prednisolone. On the molecular level, the cytokine mixture resulted in a significant reduction in E-cadherin and ILDR-1, an increase in CLDN-2, MLCK, and STAT1 phosphorylation, whereas prednisolone ameliorated the abovementioned effects induced by the cytokine mixture. This study demonstrates that prednisolone confers a direct effect in tightening the epithelial barrier, identifies novel junctional targets regulated by prednisolone, and underscores intestinal barrier restoration as a potential mechanism that contributes to the clinical efficacy of prednisolone in CD patients. KEY MESSAGES: Prednisolone confers a direct preventive effect against cytokine-induced barrier dysfunction. Prednisolone regulates the expression of CLDN-2, E-cadherin, and ILDR-1. The effect of prednisolone is GR-, MLCK-, and STAT1-dependent.

Interleukin-28A induces epithelial barrier dysfunction in CD patient-derived intestinal organoids.

Intestinal barrier dysfunction is a pathogenic hallmark in Crohn's disease (CD). Identifying key players that regulate intestinal barrier may provide novel leads for therapeutic intervention. Interleukin-28A (IL-28A) is a newly identified IL-10/interferon cytokine family member, with its most implicated function being antiviral and anti-proliferative properties. However, the role and underlying mechanisms of IL-28A in the regulation of epithelial barrier in CD remain so far unexplored. IL-28A levels were measured in the plasma and biopsies of CD patients and healthy subjects. CD patient-derived intestinal organoids were characterized by differentiation gene markers and then exposed to TNF-α, IFN-γ, IL-1ß or LPS, or IL-28A with or without GLPG0634 (filgotinib). Epithelial permeability was assessed by FITC-D4 flux. Expression of junctional components was analyzed by qRT-PCR, immunofluorescence staining, or Western blotting. JAK-STAT activity was analyzed by Western blotting. IL-28A levels were significantly increased in the plasma and biopsies from active patients with CD as compared with healthy subjects. IL-28A and its receptor complex IL-28AR/IL-10R2 were detected in CD patient-derived intestinal organoids and showed a selective response to IFN-γ exposure. IL-28A triggered epithelial barrier disruption and accompanied by reduced ZO-1 and E-cadherin expression. This effect was mediated by JAK-STAT1 pathway. Pre-incubation with the JAK1 inhibitor filgotinib ameliorated the barrier dysfunction induced by IL-28A. These results identified IL-28A as a novel regulator of epithelial barrier function and could be a putative target for CD treatment. We provide novel basic evidence that restoring intestinal barrier is a potential mechanism that contributes to the clinical benefits of JAK1 inhibitor in patients with CD.NEW & NOTEWORTHY IL-28A levels were significantly increased in the plasma and biopsies from active patients with CD as compared with healthy subjects. IFN-γ exposure stimulated IL-28A expression in intestinal organoids. Partially mimicking the effect of IFN-γ, IL-28A impaired epithelial barrier function and disrupted junctional components through the activation of JAK-STAT1 signaling, whereas JAK1 inhibitor ameliorated the above-mentioned effects of IL-28A. These findings highlight the newly identified cytokine IL-28A as a novel contributor to CD pathogenesis and could be a putative target for CD treatment. We also provide new evidence for potential applications of JAK inhibition in CD therapy.