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.

Multisegmented esophageal fully covered self-expandable metal stent for palliation of malignant dysphagia: a prospective, multicenter feasibility and safety study.

BACKGROUND AND AIMS: A novel multisegmented esophageal fully covered self-expandable metal stent (FCSEMS) was designed to reduce stent migration, which is seen in up to 30% of patients. The goal of this study was to evaluate the safety and efficacy of the multisegmented FCSEMS. METHODS: This multicenter prospective study aimed to include 30 patients undergoing palliative stent placement. Efficacy, defined as technically successful stent placement and dysphagia scores, and safety, defined as the number of adverse events (AEs) and serious AEs (SAEs), were measured. RESULTS: The study was prematurely terminated due to safety concerns after including 23 patients (mean ± standard deviation age, 72 ± 10 years; 78% male). Stent placement was technically successful in 21 patients (91%), and dysphagia scores had improved in all patients with successful stent placement. SAEs were reported in 16 (70%) patients. Stent-related mortality occurred in 3 patients (13%). CONCLUSIONS: The multisegmented FCSEMS successfully treated malignant dysphagia. The study was prematurely terminated, however, because stent placement was associated with a relatively high SAE rate. (Clinical trial registration number: NCT04415463.).

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.

Feasibility of Reduced Clinical Monitoring in Patients with Inflammatory Bowel Disease Treated with Thiopurine Therapy.

BACKGROUND: Outpatient visits and laboratory assessments are routinely scheduled every 3 to 4 months in thiopurine-treated patients with inflammatory bowel disease (IBD) to timely detect thiopurine-related adverse events (AEs). AEs that require therapy adjustment beyond 12 months of treatment are rare. AIM AND METHODS: This single-center prospective cohort study evaluated the safety of a reduced 6-monthly monitoring strategy in steroid-free patients with quiescent IBD on stable dose of azathioprine, mercaptopurine, or thioguanine monotherapy. The primary outcome was thiopurine-related AEs requiring therapy adjustments during a follow-up period of 24 months. Secondary outcomes included all AEs including laboratory toxicity, disease flares until 12 months, and the net monetary benefit from this strategy concerning IBD-related health care use. RESULTS: We enrolled 85 patients with IBD (median age 42 years, 61% Crohn's disease, 62% female), with a median disease duration of 12.5 years and median thiopurine treatment duration of 6.7 years. During follow-up, 3 patients (4%) ceased thiopurines due to AEs: recurrent infections, non-melanoma skin cancer, and gastrointestinal complaints (nausea, vomiting). At 12 months, 25 laboratory toxicities were observed (including 13% myelotoxicity, 17% hepatotoxicity); none required therapy adjustments and all were transient. A reduced monitoring strategy had a net benefit of €136 per patient. CONCLUSION: Three patients (4%) ceased thiopurine therapy due to thiopurine-related AEs, while no laboratory toxicity required therapy adjustments. Monitoring frequency of every 6 months seems feasible in patients with stable IBD on long-term (median duration > 6 years) maintenance thiopurine therapy and may contribute to reduced patient-burden and health care costs.

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.

Clinical Outcomes of Covid-19 in Patients With Inflammatory Bowel Disease: A Nationwide Cohort Study.

BACKGROUND AND AIMS: The COVID-19 risk and disease course in inflammatory bowel disease [IBD] patients remains uncertain. Therefore, we aimed to assess the clinical presentation, disease course, and outcomes of COVID-19 in IBD patients. Second, we determined COVID-19 incidences in IBD patients and compared this with the general population. METHODS: We conducted a multicentre, nationwide IBD cohort study in The Netherlands and identified patients with COVID-19. First, we assessed the COVID-19 disease course and outcomes. Second, we compared COVID-19 incidences between our IBD study cohort and the general Dutch population. RESULTS: We established an IBD cohort of 34 763 patients. COVID-19 was diagnosed in 100/34 763 patients [0.29%]; 20/100 of these patients [20%] had severe COVID-19 defined as admission to the intensive care unit, mechanical ventilation, and/or death. Hospitalisation occurred in 59/100 [59.0%] patients and 13/100 [13.0%] died. All patients who died had comorbidities and all but one were ≥65 years old. In line, we identified ≥1 comorbidity as an independent risk factor for hospitalisation (odds ratio [OR] 4.20, 95% confidence interval [CI] 1.58-11.17,; p = 0.004). Incidences of COVID-19 between the IBD study cohort and the general population were comparable (287.6 [95% CI 236.6-349.7] versus 333.0 [95% CI 329.3-336.7] per 100000 patients, respectively; p = 0.15). CONCLUSIONS: Of 100 cases with IBD and COVID-19, 20% developed severe COVID-19, 59% were hospitalised and 13% died. A comparable COVID-19 risk was found between the IBD cohort [100/34 763 = 0.29%] and the general Dutch population. The presence of ≥1 comorbidities was an independent risk factor for hospitalisation due to COVID-19.

Nearshore Zone Dynamics Determine Pathway of Organic Carbon From Eroding Permafrost Coasts.

Collapse of permafrost coasts delivers large quantities of particulate organic carbon (POC) to Arctic coastal areas. With rapidly changing environmental conditions, sediment and organic carbon (OC) mobilization and transport pathways are also changing. Here, we assess the sources and sinks of POC in the highly dynamic nearshore zone of Herschel Island-Qikiqtaruk (Yukon, Canada). Our results show that POC concentrations sharply decrease, from 15.9 to 0.3 mg L-1, within the first 100-300 m offshore. Simultaneously, radiocarbon ages of POC drop from 16,400 to 3,600 14C years, indicating rapid settling of old permafrost POC to underlying sediments. This suggests that permafrost OC is, apart from a very narrow resuspension zone (<5 m water depth), predominantly deposited in nearshore sediments. While long-term storage of permafrost OC in marine sediments potentially limits biodegradation and its subsequent release as greenhouse gas, resuspension of fine-grained, OC-rich sediments in the nearshore zone potentially enhances OC turnover.

Ustekinumab is associated with superior effectiveness outcomes compared to vedolizumab in Crohn's disease patients with prior failure to anti-TNF treatment.

BACKGROUND: Both vedolizumab and ustekinumab can be considered for the treatment of Crohn's disease (CD) when anti-TNF treatment fails. However, head-to-head trials are currently not available or planned. AIM: To compare vedolizumab and ustekinumab in Crohn´s disease patients in a prospective registry specifically developed for comparative studies with correction for confounders. METHODS: Crohn´s disease patients, who failed anti-TNF treatment and started vedolizumab or ustekinumab in standard care as second-line biological, were identified in the observational prospective Dutch Initiative on Crohn and Colitis Registry. Corticosteroid-free clinical remission (Harvey Bradshaw Index ≤4), biochemical remission (C-reactive protein ≤5 mg/L and fecal calprotectin ≤250 µg/g), combined corticosteroid-free clinical and biochemical remission, and safety outcomes were compared after 52 weeks of treatment. To adjust for confounding and selection bias, we used multiple logistic regression and propensity score matching. RESULTS: In total, 128 vedolizumab- and 85 ustekinumab-treated patients fulfilled the inclusion criteria. After adjusting for confounders, ustekinumab-treated patients were more likely to achieve corticosteroid-free clinical remission (odds ratio [OR]: 2.58, 95% CI: 1.36-4.90, P = 0.004), biochemical remission (OR: 2.34, 95% CI: 1.10-4.96, P = 0.027), and combined corticosteroid-free clinical and biochemical remission (OR: 2.74, 95% CI: 1.23-6.09, P = 0.014), while safety outcomes (infections: OR: 1.26, 95% CI: 0.63-2.54, P = 0.517; adverse events: OR: 1.33, 95% CI: 0.62-2.81, P = 0.464; hospitalisations: OR: 0.67, 95% CI: 0.32-1.39, P = 0.282) were comparable between the two groups. The propensity score matched cohort with sensitivity analyses showed comparable results. CONCLUSIONS: Ustekinumab was associated with superior effectiveness outcomes when compared to vedolizumab, while safety outcomes were comparable after 52 weeks of treatment in CD patients who have failed anti-TNF treatment.

Limited added value of laboratory monitoring in thiopurine maintenance monotherapy in inflammatory bowel disease patients.

BACKGROUND: To timely detect myelotoxicity and hepatotoxicity, laboratory monitoring at 3-month intervals is advised throughout thiopurine maintenance treatment for IBD. However, reported incidence rates of myelotoxicity and hepatotoxicity in maintenance treatment are low. AIM: To assess incidence rates and clinical consequences of myelotoxicity and hepatotoxicity in thiopurine maintenance therapy after at least 1 year of thiopurine treatment. METHODS: Retrospective analysis of therapy adjustment for laboratory toxicity in adult IBD patients after 12 consecutive months of azathioprine (AZA) or mercaptopurine monotherapy (ie baseline) between 2000 and 2016. Incidence rates of laboratory toxicity (ie myelotoxicity [leucocyte count <4.0 × 10e9/L, and/or platelet count <150 × 10e9/L] and/or hepatotoxicity (gamma-glutamyltransferase [GGT], alkaline phosphatase [AP], ALT and/or AST above ULN, excluding isolated increased AST/AP]) and associated diagnostic procedures and complications were assessed. RESULTS: In total, 12,391 laboratory assessments were performed on 1132 patients (56% female, AZA 74%) during 3.3 years of median follow-up. Median monitoring frequency was 3.1 assessments/treatment year. Only 83/12,391 (0.7%) assessments resulted in therapy adjustment, dose reduction in 46 patients, cessation in 28 and allopurinol initiation in nine; risk of therapy adjustment was 1.9% per treatment year. Incidence rates of myelotoxicity were 7.1% (5.1% mild/1.8% moderate/0.1% severe) and hepatotoxicity 5.1% (3.8% mild/1.1% moderate/0.2% severe) per treatment year. Treatment-related complications with concurrent laboratory toxicity occurred in 12 patients (1.1%) and would not have been prevented by monitoring. CONCLUSION: Severe laboratory toxicity is uncommon after 1 year of thiopurine monotherapy at 4-month monitoring intervals. Therapy adjustments are rare after detection of laboratory toxicity. After 1 year of thiopurine monotherapy, laboratory monitoring may be lowered to less than a 4-month interval.

Ustekinumab for Crohn's Disease: Results of the ICC Registry, a Nationwide Prospective Observational Cohort Study.

BACKGROUND AND AIMS: Ustekinumab is approved for the treatment of Crohn's disease [CD]. Systematically registered prospective real-world data are scarce. We therefore aimed to study the effectiveness, safety and usage of ustekinumab for CD in everyday practice. METHODS: We prospectively enrolled CD patients initiating ustekinumab in regular care between December 2016 and January 2019. Clinical (Harvey Bradshaw Index [HBI]), biochemical (C-reactive protein [CRP] and faecal calprotectin [FCP]), extra-intestinal manifestations and, peri-anal fistula activity, ustekinumab dosage, concomitant medication use, and adverse events were documented at weeks 0, 12, 24, and 52. The primary outcome was corticosteroid-free clinical remission. RESULTS: In total, 221 CD patients were included (98.6% anti-tumour necrosis factor [TNF] and 46.6% vedolizumab exposed) with a median follow-up of 52.0 weeks [interquartile range 49.3-58.4]. Corticosteroid-free clinical remission rates at weeks 24 and 52 were 38.2% and 37.1%, respectively. An initial dosing schedule of 8 weeks, compared to 12 weeks, correlated with a lower discontinuation rate [20.0% vs 42.6%, p = 0.01], but comparable corticosteroid-free clinical remission at week 52 (46.3% [q8w] vs 34.6% [q12w], p = 0.20). There was no clinical benefit of combination therapy after 52 weeks when compared to ustekinumab monotherapy [combi 40.6% vs mono 36.0%, p = 0.64]. At baseline, 28 patients had active peri-anal fistula, of whom 35.7% showed complete clinical resolution after 24 weeks. During follow-up we encountered six severe infections [3.5 per 100 patient-years], with all patients being on concomitant immunosuppressant therapies. Ustekinumab treatment discontinuation was observed in 75 [33.9%] patients mainly due to lack of response. CONCLUSION: Ustekinumab is a relatively safe and effective treatment option for CD patients with prior failure of anti-TNF and anti-integrin therapies.

Vedolizumab for Inflammatory Bowel Disease: Two-Year Results of the Initiative on Crohn and Colitis (ICC) Registry, A Nationwide Prospective Observational Cohort Study: ICC Registry - Vedolizumab.

Prospective data of vedolizumab treatment for patients with inflammatory bowel disease (IBD) beyond 1 year of treatment is scarce but needed for clinical decision making. We prospectively enrolled 310 patients with IBD (191 with Crohn's disease (CD) and 119 patients with ulcerative colitis (UC)) with a follow-up period of 104 weeks (interquartile range: 103-104) in a nationwide registry. The corticosteroid-free clinical remission rate (Harvey Bradshaw Index ≤ 4, Short Clinical Colitis Activity index ≤ 2) at weeks 52 and 104 were 28% and 19% for CD and 27% and 28% for UC, respectively. Fifty-nine percent maintained corticosteroid-free clinical remission between weeks 52 and 104. Vedolizumab with concomitant immunosuppression showed comparable effectiveness outcomes compared with vedolizumab monotherapy (week 104: 21% vs. 23%; P = 0.77), whereas 8 of 13 severe infections occurred in patients treated with concomitant immunosuppression. To conclude, the clinical effect was 19% for CD and 28% for UC after 2 years of follow-up regardless of concomitant immunosuppression.

Real-life study of safety of thiopurine-allopurinol combination therapy in inflammatory bowel disease: myelotoxicity and hepatotoxicity rarely affect maintenance treatment.

BACKGROUND: Low-dose thiopurine-allopurinol (LDTA) combination therapy is a commonly applied optimisation strategy in IBD patients with a skewed thiopurine metabolism. AIM: To assess continued LDTA maintenance treatment at annual intervals and explore risk factors for treatment cessation METHODS: Adult IBD patients treated with LDTA between 2009 and 2016 were retrospectively included. Data on the incidence of clinical and laboratory adverse events (AEs), including hepatotoxicity and myelotoxicity resulting in imposing LDTA therapy cessation and associated risk factors were collected. RESULTS: In total, 221 IBD patients (46% male, median age 42 years) were included. Maintenance LDTA treatment was continued in 78% of patients at 1 year (n = 145), 66% at 2 years (n = 83), 57% at 3 years (n = 52) and 52% at 4 years (n = 33). Treatment in patients receiving LDTA therapy for AEs during thiopurine monotherapy was more often continued than in patients initiating LDTA for other indications (eg, ineffectiveness of thiopurine monotherapy, routinely discovered skewed metabolism) (P = 0.016). Myelotoxicity during thiopurine monotherapy resolved in 87% and hepatotoxicity in 86% after median of 1.2 and 1.4 months after LDTA initiation. Cumulative incidence of AEs during LDTA resulting in therapy cessation within total follow-up of 449 treatment-years was 7% for clinical AEs, 4% for myelotoxicity and 1% for hepatotoxicity. CONCLUSION: LDTA therapy is a safe and beneficial optimisation strategy in IBD patients. Continued maintenance LDTA treatment is 52% after 4 years of treatment and most commonly affected by ineffectiveness of LDTA rather than LDTA-attributed toxicity. LDTA optimisation strategy is most advantageous in patients failing thiopurine monotherapy due to AEs.

Genotype-Guided Thiopurine Dosing Does not Lead to Additional Costs in Patients With Inflammatory Bowel Disease.

BACKGROUND AND AIMS: Decreased thiopurine S-methyltransferase [TPMT] enzyme activity increases the risk of haematological adverse drug reactions [ADRs] in patients treated with thiopurines. Clinical studies have shown that in patients with inflammatory bowel disease [IBD], pharmacogenetic TPMT-guided thiopurine treatment reduces this risk of ADRs. The aim of this study was to investigate whether this intervention impacts on healthcare costs and/or quality of life. METHODS: An a priori defined cost-effectiveness analysis was conducted in the Thiopurine response Optimization by Pharmacogenetic testing in Inflammatory bowel disease Clinics [TOPIC] trial, a randomized controlled trial performed in 30 Dutch hospitals. Patients diagnosed with IBD [age ≥18 years] were randomly assigned to the intervention [i.e. pre-treatment genotyping] or control group. Total costs in terms of volumes of care, and effects in quality-adjusted life years [QALYs], based on EuroQol-5D3L utility scores, were measured for 20 weeks. Mean incremental cost savings and QALYs with confidence intervals were calculated using non-parametric bootstrapping with 1000 replications. RESULTS: The intervention group consisted of 381 patients and the control group 347 patients. The mean incremental cost savings were €52 per patient [95% percentiles -682, 569]. Mean incremental QALYs were 0.001 [95% percentiles -0.009, 0.010]. Sensitivity analysis showed that the results were robust for potential change in costs of screening, costs of biologicals and costs associated with productivity loss. CONCLUSIONS: Genotype-guided thiopurine treatment in IBD patients reduced the risk of ADRs among patients carrying a TPMT variant, without increasing overall healthcare costs and resulting in comparable quality of life, as compared to standard treatment.

Drug Survival and Immunogenicity After Switching From Remicade to Biosimilar CT-P13 in Inflammatory Bowel Disease Patients: Two-year Follow-up of a Prospective Observational Cohort Study.

Background: The infliximab biosimilar has entered daily inflammatory bowel disease (IBD) practice. However, real-life outcomes beyond 1 year after switching are scarce. We aimed to investigate the long-term drug survival, immunogenicity, and pharmacokinetics 2 years after switching to CT-P13 in IBD patients. Methods: We performed a single-center prospective observational cohort study in all Remicade-treated IBD patients who previously switched to CT-P13. We systematically documented reasons for discontinuation, trough levels, and antidrug antibodies to infliximab (ADAs) at baseline, week 16, week 52, and week 104. Clinical and biochemical disease activity (HBI, SCCAI, CRP) and adverse events were registered. Results: Eighty-three patients were enrolled, 57 had Crohn's disease, 24 had ulcerative colitis, and 2 were IBD-unclassified. At week 104, 55 of 83 (66%) patients remained on CT-P13, and 3 were lost to follow-up. Reasons for discontinuation were loss of response (n = 10), adverse events (n = 8), and disease remission (n = 7). ADAs were present in 5/83 patients at baseline (before switching), in 2 patients before week 52, and no subsequent ADAs were detected until week 104. Median trough levels and clinical and biochemical disease activity at baseline, week 16, week 52 and week 104 did not significantly change. Conclusion: In a prospective cohort with >2-year follow-up, 66% of IBD patients continued CT-P13 after switching from Remicade. Two new cases with ADAs were observed in year 1, but subsequently no immunogenicity was detected. These results are reassuring and suggest that switching to CT-P13 does not impact long-term clinical outcomes. 10.1093/ibd/izy227_video1izy227.video15802479819001.

Genetic deficiency of NOD2 confers resistance to invasive aspergillosis.

Invasive aspergillosis (IA) is a severe infection that can occur in severely immunocompromised patients. Efficient immune recognition of Aspergillus is crucial to protect against infection, and previous studies suggested a role for NOD2 in this process. However, thorough investigation of the impact of NOD2 on susceptibility to aspergillosis is lacking. Common genetic variations in NOD2 has been associated with Crohn's disease and here we investigated the influence of these  genetic variations on the anti-Aspergillus host response. A NOD2 polymorphism reduced the risk of IA after hematopoietic stem-cell transplantation. Mechanistically, absence of NOD2 in monocytes and macrophages increases phagocytosis leading to enhanced fungal killing, conversely, NOD2 activation reduces the antifungal potential of these cells. Crucially, Nod2 deficiency results in resistance to Aspergillus infection in an in vivo model of pulmonary aspergillosis. Collectively, our data demonstrate that genetic deficiency of NOD2 plays a protective role during Aspergillus infection.

Genomic and Expression Analyses Identify a Disease-Modifying Variant for Fibrostenotic Crohn's Disease.

Background and Aims: Crohn's disease [CD] is a chronic inflammatory disease with unpredictable behaviour. More than half of CD patients eventually develop complications such as stenosis, for which they then require endoscopic dilatation or surgery, as no anti-fibrotic drugs are currently available. We aim to identify disease-modifying genes associated with fibrostenotic CD. Methods: We performed a within-case analysis comparing 'extreme phenotypes' using the Immunochip and replication of the top single nucleotide polymorphisms [SNPs] with Agena Bioscience in two independent case-control cohorts totalling 322 cases with fibrostenotis [recurrent after surgery] and 619 cases with purely inflammatory CD. Results: Combined meta-analysis resulted in a genome-wide significant signal for SNP rs11861007 [p = 6.0910-11], located on chromosome 16, in lncRNA RP11-679B19.1, an lncRNA of unknown function, and close to exon 9 of the WWOX gene, which codes for WW domain-containing oxidoreductase. We analysed mRNA expression of TGF-ß and downstream genes in ileocecal resection material from ten patients with and without the WWOX risk allele. Patients carrying the risk allele [A] showed enhanced colonic expression of TGF-ß compared to patients homozygous for the wild-type [G] allele [p = 0.0079]. Conclusion: We have identified a variant in WWOX and in lncRNA RP11-679B19.1 as a disease-modifying genetic variant associated with recurrent fibrostenotic CD and replicated this association in an independent cohort. WWOX can potentially play a crucial role in fibrostenosis in CD, being positioned at the crossroads of inflammation and fibrosis.

Patients' beliefs about medicine are associated with early thiopurine discontinuation in patients with inflammatory bowel diseases.

BACKGROUND: Patients' beliefs about medicine may either reflect the necessity for treatment or concerns regarding the treatment. We explored the extent to which these beliefs have an effect on thiopurine metabolite levels and premature discontinuation in patients with inflammatory bowel disease (IBD). PATIENTS AND METHODS: Patients enrolled in the 'Thiopurine response Optimization by Pharmacogenetic testing in Inflammatory Bowel Disease Clinics' (TOPIC) trial were asked to complete the Beliefs about Medicine Questionnaire (BMQ) 4 weeks after thiopurine initiation. The BMQ measures perceptions about treatment necessity and concerns. On the basis of the necessity and concern scores, patients can be categorized as accepting, ambivalent, indifferent, or skeptical. The thiopurine discontinuation rates for these belief subgroups were compared by Kaplan-Meier curves. Furthermore, clinical response and metabolite levels were compared between the belief subgroups. RESULTS: A total of 767 patients with IBD started thiopurine treatment, of whom 576 (75%) completed the BMQ. Patients could be classified as accepting (34%), indifferent (17%), ambivalent (34%), or skeptical (15%). Compared with patients in the accepting group (discontinuation rate 22%), patients with an indifferent (35%; P=0.02), ambivalent (37%; P<0.01), or skeptical belief (54%; P<0.01) had higher thiopurine discontinuation rates. No differences were observed in the steady-state thiopurine metabolite levels between the different belief subgroups. CONCLUSION: Patients with a low perceived treatment necessity or high concerns toward IBD treatment were more likely to discontinue thiopurine treatment prematurely. Extra attention toward these patients might prevent premature discontinuation.

Cohort profile: design and first results of the Dutch IBD Biobank: a prospective, nationwide biobank of patients with inflammatory bowel disease.

PURPOSE: The Dutch IBD Biobank aims to facilitate the discovery of predictors for individual disease course and treatment response in patients with inflammatory bowel disease (IBD). In this paper, we aim to describe the establishment of the Dutch IBD Biobank, including the facilitators and barriers to establishment. Moreover, we aim to provide a complete overview of the content of the Dutch IBD Biobank. PARTICIPANTS: Since 2007, every patient with IBD treated in one of the eight Dutch university medical centres is asked to participate in the Dutch IBD Biobank in which 225 standardised IBD-related data items and biomaterials, such as serum, DNA, biopsies and a stool sample, are collected. FINDINGS TO DATE: As of June 2014, the Dutch IBD Biobank had enrolled 3388 patients with IBD: 2118 Crohn's disease (62.5%), 1190 ulcerative colitis (35.1%), 74 IBD-unclassified (2.2%) and 6 IBD-indeterminate (0.2%). The inclusion of patients with IBD is ongoing. The quality of the biomaterials is good and serum, DNA and biopsies have been used in newly published studies. FUTURE PLANS: The genotyping (750 000 genetic variants) of all participants of the Dutch IBD Biobank is currently ongoing, enabling more genetic research. In addition, all participants will start reporting disease activity and outcome measures using an online platform and mobile app.

The NOD2 receptor is crucial for immune responses towards New World Leishmania species.

American Tegumentary Leishmaniasis is a chronic infection caused by Leishmania protozoan. It is not known whether genetic variances in NOD-like receptor (NLR) family members influence the immune response towards Leishmania parasites and modulate intracellular killing. Using functional genomics, we investigated whether genetic variants in NOD1 or NOD2 influence the production of cytokines by human PBMCs exposed to Leishmania. In addition, we examined whether recognition of Leishmania by NOD2 contributes to intracellular killing. Polymorphisms in the NOD2 gene decreased monocyte- and lymphocyte-derived cytokine production after stimulation with L. amazonensis or L. braziliensis compared to individuals with a functional NOD2 receptor. The phagolysosome formation is important for Leishmania-induced cytokine production and upregulation of NOD2 mRNA expression. NOD2 is crucial to control intracellular infection caused by Leishmania spp. NOD2 receptor is important for Leishmania recognition, the control of intracellular killing, and the induction of innate and adaptive immune responses.

Clinical Predictors of Future Nonadherence in Inflammatory Bowel Disease.

BACKGROUND: Nonadherence to medical therapy is frequently encountered in patients with inflammatory bowel disease (IBD). We aimed to identify predictors for future (non)adherence in IBD. METHODS: We conducted a multicenter prospective cohort study with adult patients with Crohn's disease (CD) and ulcerative colitis (UC). Data were collected by means of 3-monthly questionnaires on the course of disease and healthcare utilization. Medication adherence was assessed using a visual analogue scale, ranging from 0% to 100%. Levels <80% were considered to indicate nonadherence. The Brief Illness Perception Questionnaire was used to identify illness perceptions. We used a logistic regression analysis to identify patient- and disease-related factors predictive of nonadherence 3 months after the assessment of predictors. RESULTS: In total, 1558 patients with CD and 1054 patients with UC were included and followed for 2.5 years. On average, 12.1% of patients with CD and 13.3% of patients with UC using IBD-specific medication were nonadherent. Nonadherence was most frequently observed in patients using mesalazine (CD), budesonide (UC) and rectally administrated therapy (both CD and UC). A higher perceived treatment control and understanding of the disease were associated with adherence to medical therapy. Independent predictors of future nonadherence were age at diagnosis (odds ratio [OR]: 0.99 per year), nonadherence (OR: 26.91), a current flare (OR: 1.30) and feelings of anxiety/depression (OR: 1.17), together with an area under the receiver-operating-characteristics curve of 0.74. CONCLUSIONS: Lower age at diagnosis, flares, feelings of anxiety or depression, and nonadherence are associated with future nonadherence in patients with IBD. Altering illness perceptions could be an approach to improve adherence behavior.