Durability of the First Biologic in Children and Adults With Ulcerative Colitis: A Nationwide Study from the epi-IIRN

BACKGROUND

In this nationwide study, our objective was to compare the durability of first-line biologics in ulcerative colitis (UC), categorized into monotherapy and combotherapy with immunomodulators.

METHODS

We utilized data from the nationwide epi-IIRN cohort from 2005 to 2020. Durability was defined as consistent treatment without surgery. Comparisons were based on stringent propensity score-matching.

RESULTS

We included 15 111 patients with UC, of whom 2322 (15%) received biologics, with a median follow-up of 7.0 years (interquartile range, 3.8-11.0). The durability rate was similar between pediatric-onset and adults after 1 and 5 years from initiation of treatment (72% and 43% vs 71% and 43%, respectively; P = .8). Durability of adalimumab vs infliximab after 1 or 5 years was similar, whether prescribed as monotherapy (65%/46% vs 63%/33%, respectively; n = 182 matched pairs, P = .3) or combotherapy (78%/56% vs 91%/58%, respectively; n = 46 matched pairs, P = .4). Durability of infliximab was higher as combotherapy (85%/50%) vs monotherapy (69%/42%; n = 174 matched pairs, P = .007), while it was similar for adalimumab (80%/52% vs 74%/52%; n = 53 matched pairs, P = .4). The durability rate was similar for vedolizumab monotherapy (77%/56%) compared with adalimumab monotherapy (69%/52%; n = 125 matched patients, P = .1), and infliximab monotherapy (73%/55% vs 62%/44%; n = 78 matched patients, P = .1). However, combotherapy of antitumor necrosis factors (TNFs) had longer durability than vedolizumab (85%/50% vs 75%/43%, respectively; n = 131 matched pairs, P = .02).

CONCLUSION

After 5 years of treatment, 43% of the patients with UC sustained their first biologic, with similar durability in pediatric and adult-onset onset disease. Anti-TNFs had similar durability to vedolizumab and superior durability when prescribed as combotherapy.

Inflammation and bacteriophages affect DNA inversion states and functionality of the gut microbiota

Reversible genomic DNA inversions control the expression of numerous gut bacterial molecules, but how this impacts disease remains uncertain. By analyzing metagenomic samples from inflammatory bowel disease (IBD) cohorts, we identified multiple invertible regions where a particular orientation correlated with disease. These include the promoter of polysaccharide A (PSA) of Bacteroides fragilis, which induces regulatory T cells (Tregs) and ameliorates experimental colitis. The PSA promoter was mostly oriented "OFF" in IBD patients, which correlated with increased B. fragilis-associated bacteriophages. Similarly, in mice colonized with a healthy human microbiota and B. fragilis, induction of colitis caused a decline of PSA in the "ON" orientation that reversed as inflammation resolved. Monocolonization of mice with B. fragilis revealed that bacteriophage infection increased the frequency of PSA in the "OFF" orientation, causing reduced PSA expression and decreased Treg cells. Altogether, we reveal dynamic bacterial phase variations driven by bacteriophages and host inflammation, signifying bacterial functional plasticity during disease.

Durability of the First Biologic in Patients with Crohn's Disease: A Nationwide Study from the epi-IIRN

BACKGROUND

In this nationwide study we aimed to compare the durability of the first initiated biologic in Crohn's disease [CD], stratified by monotherapy and combotherapy.

METHODS

We used data from the epi-IIRN cohort, which includes 98% of the Israeli inflammatory bowel disease population [2005-2020]. Durability was defined as consistent treatment without surgery or added medications [except for combination therapy with thiopurines or methotrexate]. All comparisons were based on stringent propensity-score matching and paired time-to-event analyses.

RESULTS

A total of 19 264 patients with CD were included, of whom 7452 [39%] received biologics with a median follow-up of 6.8 years (interquartile range [IQR] 3.6-10.7). Time to biologics decreased gradually from 6.7 years [IQR 2.7-10.4] in 2005 to 0.2 years [0.07-0.23] in 2020. The durability of the first biologic after 1 and 3 years was higher with adalimumab monotherapy [88%/61%] than vedolizumab monotherapy [81%/59%; n = 394 matched patients, p = 0.04] and similar between infliximab monotherapy and vedolizumab monotherapy [65%/43%; n = 182 matched patients, p = 0.1]. Durability was higher in adalimumab monotherapy vs infliximab monotherapy [83%/62% vs 71%/48% at 1/3 years; p <0.001] and it was similar in adalimumab monotherapy vs infliximab combotherapy [87%/63% vs 80%/58%, respectively; p = 0.1]. Durability was higher in combotherapy compared with monotherapy for both infliximab [85%/64% vs 67%/43%, respectively; n = 496 matched pairs, p <0.001], and adalimumab [93%/76% vs 82%/62%, respectively; n = 540 matched pairs, p <0.001].

CONCLUSION

Durability of the first biologic in CD was highest for adalimumab monotherapy. Combotherapy further increased the durability of adalimumab and infliximab. Unless otherwise indicated, our data may support using anti-tumour necrosis factors [TNFs] as first-line biologics in CD, particularly adalimumab if monotherapy is advised.

A personalized network framework reveals predictive axis of anti-TNF response across diseases

Personalized treatment of complex diseases has been mostly predicated on biomarker identification of one drug-disease combination at a time. Here, we use a computational approach termed Disruption Networks to generate a data type, contextualized by cell-centered individual-level networks, that captures biology otherwise overlooked when performing standard statistics. This data type extends beyond the "feature level space", to the "relations space", by quantifying individual-level breaking or rewiring of cross-feature relations. Applying Disruption Networks to dissect high-dimensional blood data, we discover and validate that the RAC1-PAK1 axis is predictive of anti-TNF response in inflammatory bowel disease. Intermediate monocytes, which correlate with the inflammatory state, play a key role in the RAC1-PAK1 responses, supporting their modulation as a therapeutic target. This axis also predicts response in rheumatoid arthritis, validated in three public cohorts. Our findings support blood-based drug response diagnostics across immune-mediated diseases, implicating common mechanisms of non-response.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Association of Antibiotic Use with Durability of Biologic Agents in Inflammatory Bowel Disease: a Report from the epi-IIRN

BACKGROUND

Different antibiotic classes were reported to have variable effects on immunogenicity towards anti-tumour necrosis factor [TNF] agents. However, the impact of antibiotic administration on biologic treatment durability was not investigated. We aimed to assess the association between antibiotic treatment and persistence of different classes of biologic therapy in inflammatory bowel disease [IBD] patients.

METHODS

Data from the epi-IIRN, a nationwide registry of all Israeli IBD patients were analysed. All patients who filled a prescription of either infliximab, adalimumab, vedolizumab, or ustekinumab, were included. Treatment cessation was defined as drug discontinuation of at least 6 months. Macrolides, cephalosporins, fluoroquinolones, and penicillins with beta-lactamase inhibitors were selected as primary exposure variables. Survival analysis was performed using marginal structural models for each drug separately.

RESULTS

In all 13 513 IBD patients, with a total of 39 600 patient-years, were included. Significant differences of overall treatment persistence were demonstrated, with highest persistence rates for ustekinumab and the lowest for infliximab treatment. Macrolides were found to be significantly associated with reduced risk of infliximab cessation (adjusted hazard ratio [aHR] 0.72, 95% CI 0.62-0.89]. Fluoroquinolones and cephalosporins were associated with an elevated risk of adalimumab treatment cessation [aHR 1.33, 95% CI 1.22-1.46; and aHR 1.20, 95% CI 1.08-1.34, respectively]. No significant effects of the studied antibiotics were observed in ustekinumab and vedolizumab users.

CONCLUSIONS

Specific antibiotic classes are associated with duration of anti-TNF treatment, but not with durability of vedolizumab or ustekinumab treatments. Further research is required to study the effect of specific antibiotics on response to biologics.

Differential Serum-intestinal Dynamics of Infliximab and Adalimumab in Inflammatory Bowel Disease Patients

BACKGROUND AND AIMS

Therapeutic drug monitoring is used to guide anti-tumour necrosis factor [TNF] therapy. However, the associations between serum drug levels [SDL], TNF-bound, and free anti-TNF in the target tissue are incompletely defined. We aimed to assess the interactions between these parameters in inflammatory bowel disease [IBD] patients.

METHODS: ENZYME-LINKED IMMUNOSORBENT

assays [ELISA assays] were used to detect free drug and TNF-drug complexes in intestinal tissues. Concurrent SDL, anti-drug antibodies [ADA], pharmacotherapy, clinical response, endoscopic appearance, and histological severity were determined. Comparisons between anti-TNFs and paired inflamed/non-inflamed tissue were performed. Variables were correlated and potential interactions detected using multivariate analysis.

RESULTS

A total of 95 biopsies taken from 49 anti-TNF treated IBD patients [26 receiving infliximab and 23 adalimumab] were studied. Free drug levels were higher in inflamed compared with non-inflamed paired specimens. Tissue free-drug and TNF-drug complexes levels were higher in adalimumab-treated patients. In adalimumab-treated patients, SDL were correlated with free drug, but not TNF-drug complex levels, in both inflamed and non-inflamed segments. In infliximab-treated patients, higher SDL were associated with the presence of tissue free drug in both inflamed and non-inflamed segments, whereas TNF-drug complexes were mostly detected in non-inflamed but not in inflamed tissue. In the presence of ADA, neither free drug nor TNF-infliximab complexes were measured in the tissue. Tissue levels did not correlate well with clinical, endoscopic, or histological scores.

CONCLUSIONS

SDL correlated with tissue free drug levels; however, different dynamics were observed for TNF-drug complex levels. Infliximab and adalimumab tissue drug dynamics differ. Better understanding of these interactions may allow future therapeutic optimisation.

Improved Outcomes of Paediatric and Adult Crohn's Disease and Association With Emerging Use of Biologics-A Nationwide Study From the Epi-IIRN

BACKGROUND

The effectiveness of biologics for improving long-term outcomes in patients with Crohn's disease [CD] is still controversial. In this nationwide study, we aimed to evaluate trends of long-term outcomes in all CD patients in Israel during the biologics era.

METHODS

Trends of outcomes were analysed using data from the four Israeli health maintenance organisations, covering 98% of the population; joinpoint regression models were used to explore changes of these trends over 2005 to 2019.

RESULTS

A total of 16 936 patients were diagnosed with CD in Israel since 2005 (2932 [17%] paediatric onset, 14 004 [83%] adult onset) with 114 947 person-years of follow-up. The cumulative rate of any CD related surgery was 5%, 9%, 11%, and 14% at 1, 3, 5, and 10 years from diagnosis. The increase in use of biologics was sharp (from 8.9% to 36%; average annual percent change [AAPC], 14.3%), and the time to biologics was shorter in recent years (median time of 4.8 [1.9-8.1] years in those diagnosed in 2005-2008 compared with 0.5 [0.2-1.1] years in those diagnosed in 2015-2018; p < 0.001). A significant decrease was noted in the hazard of hospitalisations (1.3 [0.1-4.6] years compared with 0.2 [0.02-0.9] years; p < 0.001), steroid dependency (1.5 [0.2-5.4] years compared with 0.1 [0.02-0.4] years; p < 0.001), and intestinal surgeries [4.7 [1.6-8.2] years compared with 0.6 [0.2-1.4] years; p < 0.001), but not of perianal surgery (4.2 [1.1-7.7] years compared with 0.6 [0.2-1.4] years; p = 0.2). Outcomes were consistently worse in paediatric onset compared with adults.

CONCLUSIONS

The rates of hospitalisations, steroid dependency, and intestinal resections decreased in association with increased use of biologics both in children and in adults, but not the rate of perianal surgeries.

Colectomy Rates did not Decrease in Paediatric- and Adult-Onset Ulcerative Colitis During the Biologics Era: A Nationwide Study From the epi-IIRN

BACKGROUND

It is still of debate whether the advent of biologics has been associated with a change in the natural history of ulcerative colitis [UC]. In this nationwide study we evaluated trends of long-term outcomes in all patients diagnosed with UC in Israel during the biologic era.

METHODS

Data in the epi-IIRN cohort were retrieved from the four Israeli Health Maintenance Organizations covering 98% of the population, and linked to the Ministry of Health prospective registry on surgeries and hospitalizations. Joinpoint Regression and Kaplan-Meier survival analyses were used, reporting annual average percentage change [AAPC] for each outcome.

RESULTS

A total of 13 231 patients were diagnosed with UC since 2005 (1426 [11%] paediatric-onset, 10 310 [78%] adults, 1495 [11%] elderly) with 93 675 person-years of follow-up. The probabilities of surgery after 1, 3 and 5 years from diagnosis were 1.1, 2.3 and 4.1%, respectively, and the corresponding rates of hospitalizations were 22, 33 and 41%. The overall utilization of biologics in UC increased from 0.1% in 2005 to 9.6% in 2019 [AAPC 22.1%] and they were prescribed earlier during the disease course (median of 5.6 years [interquartile range 2.8-9.1] in 2005-2008 vs 0.8 years [0.4-1.5] in 2015-2018; p < 0.001]. Annual rates of surgeries [AAPC -1.3; p = 0.6] and steroid-dependency [AAPC -1.2; p = 0.3] remained unchanged, while rates of hospitalizations slightly decreased [AAPC -1.2; p < 0.001]. Outcomes were consistently worse in paediatric-onset disease than in adults, despite higher utilization of biologics [28% vs 12%, respectively; p < 0.001].

CONCLUSION

During the biologic era rates of surgeries and steroid-dependency have remained unchanged in patients with UC, while rates of hospitalizations have slightly decreased.

COVID-19 in Patients with Inflammatory Bowel Disease: The Israeli Experience

Background: Crohn’s disease (CD) and ulcerative colitis (UC) are chronic, immune-mediated inflammatory bowel diseases (IBD) affecting millions of people worldwide. IBD therapies, designed for continuous immune suppression, often render patients more susceptible to infections. The effect of the immune suppression on the risk of coronavirus disease-19 (COVID-19) is not fully determined yet. Objective: To describe COVID-19 characteristics and outcomes and to evaluate the association between IBD phenotypes, infection outcomes and immunomodulatory therapies. Methods: In this multi-center study, we prospectively followed IBD patients with proven COVID-19. De-identified data from medical charts were collected including age, gender, IBD type, IBD clinical activity, IBD treatments, comorbidities, symptoms and outcomes of COVID-19. A multivariable regression model was used to examine the effect of immunosuppressant drugs on the risk of infection by COVID-19 and the outcomes. Results: Of 144 IBD patients, 104 (72%) were CD and 40 (28%) were UC. Mean age was 32.2 ± 12.6 years. No mortalities were reported. In total, 94 patients (65.3%) received biologic therapy. Of them, 51 (54%) at escalated doses, 10 (11%) in combination with immunomodulators and 9 (10%) with concomitant corticosteroids. Disease location, behavior and activity did not correlate with the severity of COVID-19. Biologics as monotherapy or with immunomodulators or corticosteroids were not associated with more severe infection. On the contrary, patients receiving biologics had significantly milder infection course (p = 0.001) and were less likely to be hospitalized (p = 0.001). Treatment was postponed in 34.7% of patients until recovery from COVID-19, without consequent exacerbation. Conclusion: We did not witness aggravated COVID-19 outcomes in patients with IBD. Patients treated with biologics had a favorable outcome.

Antibiotic use differentially affects the risk of anti-drug antibody formation during anti-TNFα therapy in inflammatory bowel disease patients: a report from the epi-IIRN

OBJECTIVE

Anti-drug antibodies (ADA) to anti-tumour necrosis factor (anti-TNF) therapy drive treatment loss of response. An association between intestinal microbial composition and response to anti-TNF therapy was noted. We therefore aimed to assess the implications of antibiotic treatments on ADA formation in patients with inflammatory bowel disease (IBD).

DESIGN

We analysed data from the epi-IIRN (epidemiology group of the Israeli IBD research nucleus), a nationwide registry of all patients with IBD in Israel. We included all patients treated with anti-TNF who had available ADA levels. Survival analysis with drug use as time varying covariates were used to assess the association between antibiotic use and ADA development. Next, specific pathogen and germ-free C57BL mice were treated with respective antibiotics and challenged with infliximab. ADA were assessed after 14 days.

RESULTS

Among 1946 eligible patients, with a median follow-up of 651 days from initiation of therapy, 363 had positive ADA. Cox proportional hazard model demonstrated an increased risk of ADA development in patients who used cephalosporins (HR=1.97, 95% CI 1.58 to 2.44), or penicillins with β-lactamase inhibitors (penicillin-BLI, HR=1.4, 95% CI 1.13 to 1.74), whereas a reduced risk was noted in patients treated with macrolides (HR=0.38, 95% CI 0.16 to 0.86) or fluoroquinolones (HR=0.20, 95% CI 0.12 to 0.35). In mice exposed to infliximab, significantly increased ADA production was observed in cephalosporin as compared with macrolide pretreated mice. Germ-free mice produced no ADA.

CONCLUSION

ADA production is associated with the microbial composition. The risk of ADA development during anti-TNF therapy can possibly be reduced by avoidance of cephalosporins and penicillin-BLIs, or by treatment with fluoroquinolones or macrolides.

Efficacy of Biologic Drugs in Short-Duration Versus Long-Duration Inflammatory Bowel Disease: A Systematic Review and an Individual-Patient Data Meta-Analysis of Randomized Controlled Trials

BACKGROUND AND AIMS

Starting biologic treatment early in the course of inflammatory bowel disease (IBD) may be associated with higher efficacy, especially in Crohn's disease (CD).

METHODS

This was a systematic review and individual-patient data meta-analysis of all placebo-controlled trials of biologics approved for IBD at study inception (October 2015), using Vivli data-sharing platform. The primary outcome was the proportional biologic/placebo treatment effect on induction of remission in patients with short-duration (≤18 months) vs long-duration disease (>18 months) analyzed separately for CD and ulcerative colitis (UC). We used meta-regression to examine the impact of patients' characteristics on the primary outcome.

RESULTS

We included 25 trials, testing infliximab, adalimumab, certolizumab, golimumab, natalizumab, or vedolizumab (6168 patients with CD and 3227 patients with UC). In CD, remission induction rates were higher in pooled placebo and patients in active arms with short-duration disease of ≤18 months (41.4% [244 of 589]) compared with disease duration of >18 months (29.8% [852 of 2857], meta-analytically estimated odds ratio, 1.33; 95% confidence interval, 1.09-1.64). The primary outcome, proportional biologic/placebo treatment effect on induction of remission, was not different in short-duration disease of ≤18 months (n = 589, odds ratio, 1.47; 95% confidence interval, 1.01-2.15) compared with longer disease duration (n = 2857, odds ratio, 1.43; 95% confidence interval, 1.19-1.72). In UC trials, both the proportional biologic/placebo remission-induction effect and the pooled biologic-placebo effect were stable, regardless of disease duration. Primary outcome results remained unchanged when tested using alternative temporal cutoffs and when modeled for individual patient's covariates, including prior anti-tumor necrosis factor exposure.

CONCLUSIONS

There are higher rates of induction of remission with biologics and with placebo in early CD, resulting in a treatment to placebo effect ratio that is similar across disease durations. No such relationships between disease duration and outcomes was found in UC. PROSPERO registration: CRD42018041961.

Epidemiology of Inflammatory Bowel Diseases in Israel: A Nationwide Epi-Israeli IBD Research Nucleus Study

BACKGROUND

There are currently no nationwide data on the epidemiology of inflammatory bowel diseases (IBD) in Israel. We aimed to determine the population-based epidemiological trends of IBD in the diverse Israeli population.

METHODS

Health-administrative data were retrieved from all 4 Israeli health maintenance organizations, insuring 98% of the population, using validated identification algorithms. National trends were determined using Joinpoint regression analysis calculating annual percent change and average annual percent change (AAPC).

RESULTS

By 2019, there were 46,074 patients with IBD in Israel, corresponding to a national prevalence of 519/100,000 (0.52%), of whom 54.1% had Crohn disease (CD) and 45.9% had ulcerative colitis (UC). The number of Jewish patients doubled from 18,701 in 2005 (354/100,000) to 38,950 (589/100,000) in 2018 (AAPC, +4.0%; P < 0.05), and the number of Arab patients increased 3-fold from 1096 (102.1/100,000) to 3534 (240.7/100,000; AAPC, +6.8%; P < 0.05) during the same years. However, the increase rate has gradually decelerated over time (annual percent change during 2005-2008, 2009-2014, and 2005-2018 was +6.7%, +4.2%, and +2.3%, respectively; P < 0.05). Pediatric prevalence increased from 37.4 to 52.2/100,000, with CD predominating in both Jews and Arabs. The incidence of CD remained stable (from 15.9/100,000 to 14.9/100,000) and the incidence of UC decreased (15.4/100,000 to 10.5/100,000 (AAPC, -3.2%; P < 0.001)). In contrast, pediatric incidence of CD increased from 7.3/100,000 to 8.3/100,000 (AAPC, +1.9%; P < 0.05) and that of UC increased from 2.6 to 4.4/100,000 (AAPC, +5.8%; P < 0.05).

CONCLUSIONS

The IBD prevalence rate in Israel is still increasing but gradually decelerating, probably due to the decreasing overall IBD incidence. Nonetheless, incidence rate in children is still increasing. Ongoing narrowing in the rates between Jews and Arabs over time may indicate shared environmental factors.

Dose optimisation for Loss of Response to Vedolizumab- Pharmacokinetics and Immune Mechanisms

BACKGROUND

Real life data regarding pharmacokinetics of vedolizumab in patients needing dose optimisation are scarce. We set to examine whether pre-optimisation vedolizumab levels associate with therapy outcomes and which mechanisms explain the associations.

METHODS

A multicentre observational study assessed the outcome of dose increase in association with pre-escalation levels in vedolizumab-treated patients. SubsequentIy, α4β7 occupancy on peripheral blood [PB] and intestinal lamina propria [LP] tissues was investigated on various cellular subsets in patients undergoing lower endoscopy on infusion day. Cellular localisation of vedolizumab-bound α4β7 and effects on M1 and M2 macrophages were also explored.

RESULTS

A total of 161 inflammatory bowel disease [IBD] patients were included. Among 129/161 patients intensified during maintenance [Week 14 onward], pre-intensification trough levels were comparable or higher among those subsequently attaining post-optimisation clinical, biomarker, and endoscopic remission, compared with non-remitting patients [p = 0.09, 0.25, 0.04, respectively]. Similar results were demonstrated for those dose-optimised during induction [Week 6, n = 32]. In the immune sub-study [n = 43], free α4β7 receptors at trough were similarly low among patients with/without mucosal healing, on PB T cells [p = 0.15], LP T cells [p = 0.88], and on PB eosinophils [p = 0.08]. Integrin receptors on M1 and M2 macrophages were also saturated by low levels of vedolizumab and anti-inflammatory cytokine secretion was not increased. Co-localisation and dissociation experiments demonstrated membranal α4β7 receptors of two origins: non-internalised and newly generated α4β7, but re-binding was still complete at very low concentrations.

CONCLUSIONS

These results do not support pharmacokinetics as the mechanism responsible for loss of response to vedolizumab, nor do they support a need for higher drug concentration to enhance vedolizumab's immune effects. Higher pre-escalation levels may indicate less clearance [less severe disease] and higher likelihood of subsequent re-gained response, regardless of therapy escalation.

Volume of fluid consumption during preparation for colonoscopy is possibly the single most important determinant of bowel preparation adequacy

Background

The effectiveness and safety of colonoscopy are directly dependent on the quality of bowel preparation. Multiple risk factors for inadequate bowel preparation (IBP) have been identified; however, IBP is still reported in 20-30% of cases in most studies. We aimed to identify modifiable predictors of the adequacy of bowel preparation using sodium picosulfate, and to recommend easily modifiable parameters to increase the success rate of colonoscopies.

Methods

This was a single-center observational study of adult outpatients referred for an elective colonoscopy. Patients were interviewed prior to colonoscopy; volume of liquids consumed was calculated as number of 200-mL cups showed to the patient. Additional information, including medical history, diagnoses and regular medications, was procured from patients’ medical records. Univariate and multivariate regression analyses were performed to identify factors significantly associated with IBP in a subgroup analysis of high-risk patients.

Results

The rate of IBP in 1172 subjects was 19.4%. This rate decreased as fluid consumption increased, with a further drop associated with shorter intervals from end of preparation to colonoscopy. Drinking < 1.4 L significantly increased the risk of IBP (odds ratio [OR] 3.62, 95% confidence interval [CI] 2.65-4.95), while drinking ≥2 L was associated with adequate preparation (OR 0.09, 95%CI 0-0.42). These associations were stronger in high-risk individuals.

Conclusion

Greater fluid intake and short interval to colonoscopy are easily modifiable parameters that can substantially reduce the rate of IBP, especially among high-risk individuals.

Early Indolent Course of Crohn's Disease in Newly Diagnosed Patients Is Not Rare and Possibly Predictable

BACKGROUND & AIMS

The early stages of Crohn's disease (CD) course are heterogeneous, and it is a challenge to predict the course of disease in patients with new diagnosis.

METHODS

We performed an observational longitudinal study of 156 adults (79 male; median age, 27.7 years; 57 treatment naïve) with newly diagnosed CD (within 6 months of enrollment), referred from medical centers and community clinics in Israel from 2013 through 2017. Study participants each received semi-annual scheduled evaluations. Indolent disease was defined as a disease course without need for strict interventions to control complicated course of CD (hospitalization or surgery, or decision to start steroid, immunomodulator, or biologic therapy). Cox regression and receiver operating characteristic analyses were used to identify factors associated with early indolent or complicated course of CD. We validated our findings in an independent cohort of patients with CD from a separate medical center in Israel in 2018.

RESULTS

Over a median follow-up period of 17.2 months (interquartile range, 8.8-23.8 months), 52 patients (33.3%) had an indolent course of CD, 29 (18.5%) required hospitalizations, and 75 (48%) were recommended to start steroid, immunomodulator, or biologic therapies. The median time to first intervention was 3.4 months (95% CI, 2.4-4.4). We developed a model based on clinical factors that identified 4 factors associated with complicated course in treatment-naïve patients: body mass index <25 kg/m² (hazard ratio [HR], 2.45; 95% CI, 1.07-5.43; P = .033), serum level of vitamin B12 <350 pg/mL (HR, 2.78; 95% CI, 1.21-6.41; P = .016), white blood cells ≥7 × 10³/μL (HR, 2.419; 95% CI, 1.026-5.703; P = .044), and serum level of ALT ≥25 IU/L (HR, 2.680; 95% CI, 1.186-6.058; P = .018). This model discriminated between patients with vs without a complicated course of disease with 90% and 89% accuracy at 6 and 12 months after diagnosis, respectively. A validation cohort demonstrated a discriminatory ability of 79% at 3 months after diagnosis, and a nomogram was constructed.

CONCLUSIONS

In an observational longitudinal study of 156 patients with newly diagnosed CD, we found that one third have an early indolent course of disease. We identified factors that can be measured at diagnosis to identify patients at risk for an early complicated course-these might be used in patient management and selection of treatment.

Oral Capsulized Fecal Microbiota Transplantation for Eradication of Carbapenemase-producing Enterobacteriaceae Colonization With a Metagenomic Perspective

BACKGROUND

Carbapenemase-producing Enterobacteriaceae (CPE) infections lead to considerable morbidity and mortality. We assessed the potential of fecal microbiota transplantation (FMT) to eradicate CPE carriage and aimed to explain failure or success through microbiome analyses.

METHODS

In this prospective cohort study, all consenting eligible CPE carriers received oral capsulized FMT for 2 days. Primary outcome was CPE eradication at 1 month, defined by 3 consecutive negative rectal swabs, the last also negative for carbapenemase gene by polymerase chain reaction. Comprehensive metagenomics analysis of the intestinal microbiome of donors and recipients before and after FMT was performed.

RESULTS

Fifteen CPE carriers received FMT, 13 of whom completed 2 days of treatment. CPE eradication at 1 month was successful in 9/15 and 9/13, respectively. Bacterial communities showed significant changes in both beta and alpha diversity metrics among participants who achieved CPE eradication that were not observed among failures. Post-FMT samples' beta-diversity clustered according to the treatment outcome, both in taxonomy and in function. We observed a significant decrease in beta diversity in participants who received post-FMT antibiotics. Enterobacteriaceae abundance decreased in post-FMT samples of the responders but increased among failures. Functionally, a clear demarcation between responders (who were similar to the donors) and failures was shown, driven by antimicrobial resistance genes.

CONCLUSIONS

Our study provides the biological explanation for the effect of FMT against CPE carriage. Decolonization of CPE by FMT is likely mediated by compositional and functional shifts in the microbiome. Thus, FMT might be an efficient strategy for sustained CPE eradication.

CLINICAL TRIALS REGISTRATION

NCT03167398.

Duration of combination therapy and risk of treatment failure in patients with inflammatory bowel disease

BACKGROUND

Patients who receive infliximab (IFX) combined with a thiopurine, for inflammatory bowel disease, have a better clinical response and less frequent immunization towards IFX than those treated with IFX alone. The benefits of combination therapy must be weighed against the risks of infection and cancer. We studied the association between the duration of combination therapy and the risk of treatment failure by two year from initiation.

METHODS

Participants had Crohn's disease or ulcerative colitis and were in clinical and biological remission, 6 months after initiation of combination therapy. The risk of subsequent treatment failure (i.e., undetectable trough IFX levels and/or clinical relapse followed by surgical treatment or switch of maintenance treatment) was estimated using Kaplan-Meier method and adjusted Hazard Ratios (aHRs), in patients whohadreceived 6 to 11 months vs. 12 months or more of combination therapy. We performed a similar analysis in which the follow-up was started at discontinuation of the immunosuppressant.

RESULTS

Among 139 patients (48% women; median age 31.1), with a median follow-up of 18.9 months, we observed 26 treatment failures (including 15 patients with undetectable trough IFX levels). After adjustment for gender and type of immunomodulator, a shorter duration of combination therapy was not associated with a higher risk of treatment failure (aHR=0.42; 95% confidence interval (95%CI): 0.13-1.40; p=0.16). When the follow-up was started at discontinuation of the immunosuppressant, a combination therapy of 6-11 months was associated with a numerically lower risk of treatment failure as compared with a longer combination therapy (HR=0.12; 95%CI: 0.01-1.05; p=0.055).

CONCLUSION

Our results do not show any benefit for continuation of combination therapy for more than 12 months after achieving clinical remission in IBD patients.

COVID-19 Pandemic: Which IBD Patients Need to Be Scoped-Who Gets Scoped Now, Who Can Wait, and how to Resume to Normal

Endoscopy is an essential component in the management of inflammatory bowel disease [IBD]. There is a risk of SARS-CoV-2 transmission during endoscopic procedures. The International Organization for the study of IBD [IOIBD] has developed 11 position statements, based on an online survey, that focus on how to prioritise endoscopies in IBD patients during the COVID-19 pandemic, alternative modes for disease monitoring, and ways to triage the high number of postponed endoscopies after the pandemic. We propose to pre-screen patients for suspected or confirmed COVID-19 and test for SARS-CoV-2 before endoscopy if available. High priority endoscopies during pandemic include acute gastrointestinal bleed, acute severe ulcerative colitis, new IBD diagnosis, cholangitis in primary sclerosing cholangitis, and partial bowel obstruction. Alternative modes of monitoring using clinical symptoms, serum inflammatory markers, and faecal calprotectin should be considered during the pandemic. Prioritising access to endoscopy in the post-pandemic period should be guided by control of COVID-19 in the local community and availability of manpower and personal protective equipment. Endoscopy should be considered within 3 months after the pandemic for patients with a past history of dysplasia and endoscopic resection for dysplastic lesion. Endoscopy should be considered 3-6 months after the pandemic for assessment of postoperative recurrence or new biologic initiation. Endoscopy can be postponed until after 6 months of pandemic for routine IBD surveillance and assessment of mucosal healing.

Clinicogenomic factors of biotherapy immunogenicity in autoimmune disease: A prospective multicohort study of the ABIRISK consortium

BACKGROUND

Biopharmaceutical products (BPs) are widely used to treat autoimmune diseases, but immunogenicity limits their efficacy for an important proportion of patients. Our knowledge of patient-related factors influencing the occurrence of antidrug antibodies (ADAs) is still limited.

METHODS AND FINDINGS

The European consortium ABIRISK (Anti-Biopharmaceutical Immunization: prediction and analysis of clinical relevance to minimize the RISK) conducted a clinical and genomic multicohort prospective study of 560 patients with multiple sclerosis (MS, n = 147), rheumatoid arthritis (RA, n = 229), Crohn's disease (n = 148), or ulcerative colitis (n = 36) treated with 8 different biopharmaceuticals (etanercept, n = 84; infliximab, n = 101; adalimumab, n = 153; interferon [IFN]-beta-1a intramuscularly [IM], n = 38; IFN-beta-1a subcutaneously [SC], n = 68; IFN-beta-1b SC, n = 41; rituximab, n = 31; tocilizumab, n = 44) and followed during the first 12 months of therapy for time to ADA development. From the bioclinical data collected, we explored the relationships between patient-related factors and the occurrence of ADAs. Both baseline and time-dependent factors such as concomitant medications were analyzed using Cox proportional hazard regression models. Mean age and disease duration were 35.1 and 0.85 years, respectively, for MS; 54.2 and 3.17 years for RA; and 36.9 and 3.69 years for inflammatory bowel diseases (IBDs). In a multivariate Cox regression model including each of the clinical and genetic factors mentioned hereafter, among the clinical factors, immunosuppressants (adjusted hazard ratio [aHR] = 0.408 [95% confidence interval (CI) 0.253-0.657], p < 0.001) and antibiotics (aHR = 0.121 [0.0437-0.333], p < 0.0001) were independently negatively associated with time to ADA development, whereas infections during the study (aHR = 2.757 [1.616-4.704], p < 0.001) and tobacco smoking (aHR = 2.150 [1.319-3.503], p < 0.01) were positively associated. 351,824 Single-Nucleotide Polymorphisms (SNPs) and 38 imputed Human Leukocyte Antigen (HLA) alleles were analyzed through a genome-wide association study. We found that the HLA-DQA1*05 allele significantly increased the rate of immunogenicity (aHR = 3.9 [1.923-5.976], p < 0.0001 for the homozygotes). Among the 6 genetic variants selected at a 20% false discovery rate (FDR) threshold, the minor allele of rs10508884, which is situated in an intron of the CXCL12 gene, increased the rate of immunogenicity (aHR = 3.804 [2.139-6.764], p < 1 × 10-5 for patients homozygous for the minor allele) and was chosen for validation through a CXCL12 protein enzyme-linked immunosorbent assay (ELISA) on patient serum at baseline before therapy start. CXCL12 protein levels were higher for patients homozygous for the minor allele carrying higher ADA risk (mean: 2,693 pg/ml) than for the other genotypes (mean: 2,317 pg/ml; p = 0.014), and patients with CXCL12 levels above the median in serum were more prone to develop ADAs (aHR = 2.329 [1.106-4.90], p = 0.026). A limitation of the study is the lack of replication; therefore, other studies are required to confirm our findings.

CONCLUSION

In our study, we found that immunosuppressants and antibiotics were associated with decreased risk of ADA development, whereas tobacco smoking and infections during the study were associated with increased risk. We found that the HLA-DQA1*05 allele was associated with an increased rate of immunogenicity. Moreover, our results suggest a relationship between CXCL12 production and ADA development independent of the disease, which is consistent with its known function in affinity maturation of antibodies and plasma cell survival. Our findings may help physicians in the management of patients receiving biotherapies.

Propagation of EBV-driven Lymphomatous Transformation of Peripheral Blood B Cells by Immunomodulators and Biologics Used in the Treatment of Inflammatory Bowel Disease

BACKGROUND

Immunomodulators and anti tumor-necrosis-α antibodies (anti-TNFs) have been implicated in increased risk of Epstein-Barr virus (EBV)-driven B-cell lymphoproliferative disorders in inflammatory bowel disease (IBD) patients. However, the underlying mechanisms are poorly understood.

METHODS

An in-vitro model of lymphoblastoid cell line (LCL) was established by co-incubation of EBV-infected human peripheral blood mononuclear cells (PBMC) with Cyclosporin-A (CSA). After 4 weeks, the resultant LCLs were analyzed by flow cytometry, telomerase activity assay, and next generation sequencing. Subsequently, LCLs were explored in the presence of therapeutic agents for IBD (anti-TNFs, vedolizumab, 6-Mercaptopurine [6MP], methotrexate). Epstein-Barr virus titers were quantitated by real-time polymerase chain reaction.

RESULTS

In cultures of PBMC with EBV and CSA, LCLs were characterized as an expanded, long lived population of CD58+CD23hi B-cells with high telomerase activity and clonal expansion. Upon addition to the cell cultures, LCL percentages were higher with infliximab (median 19.21%, P = 0.011), adalimumab (median 19.85%, P = 0.003), and early washed-out 6MP (median 30.57%, P = 0.043) compared with PBMC with EBV alone (median 9.61%). However, vedolizumab had no such effect (median 8.97%; P = 0.435). Additionally, LCL expansion was accompanied by increase in intracellular, rather than extracellular, EBV viral copies. Compared with PBMC with EBV alone, high levels of LCL were subsequently observed after triple depletion of NK cells, CD4+ T cells, and CD8+ T cells (median 52.8% vs 16.4%; P = 0.046) but also in cultures depleted solely of CD4+ T cells (median 30.7%, P = 0.046).

CONCLUSIONS

These results suggest that both anti-TNFs and 6MP, but not vedolizumab, propagate EBV-driven lymphoblastoid transformation in an in vitro model of lymphoma. This model may prove useful for studying mechanisms underlying proneoplastic viral immune interactions of novel drugs in IBD therapy.

Intratumoral HLA-DR-/CD33+/CD11b+ Myeloid-Derived Suppressor Cells Predict Response to Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer

Capecitabine-based neoadjuvant chemoradiation therapy (nCRT) is currently the mainstay of treatment for locally advanced rectal cancer (LARC), prior to surgical tumor removal. While response to this treatment is partial, it carries significant risk of side effects. As of today, there is no accepted model to predict tumor response, and allow for patient stratification. The level of circulating Myeloid-derived suppressor cells (MDSCs), a subpopulation of early myeloid cells (EMCs), has been shown to correlate with prognosis and response to therapy in advanced colon cancer, but their role in LARC is not clear. We sought to study the effect of intratumoral and circulating levels of different EMCs subpopulations including MDSCs on response to nCRT. We analyzed tumor, normal mucosa, and peripheral blood samples from 25 LARC patients for their different EMCs subpopulation before and after nCRT, and correlated them with degree of pathologic response, as determined postoperatively. In addition, we compared LARC patient to 10 healthy donors and 6 metastatic patients. CD33⁺HLA-DR⁻CD16⁻CD11b⁺EMCs in the circulation of LARC patients were found to inhibit T-cell activation. Furthermore, elevated levels of CD33⁺HLA-DR⁻ myeloid cells were found in the tumor relative to normal mucosa, but not in the circulation when compared to healthy subjects. Moreover, intratumoral, but not circulating levels of MDSCs correlated with clinical stage and response to therapy in patients treated with nCRT, with high levels of MDSCs significantly predicting poor response to nCRT. Importantly, therapy by itself, had significant differential effects on MDSC levels, leading to increased circulating MDSCs, concomitantly with decreasing intratumoral MDSCs. Our results suggest that high levels of intratumoral, but not circulating MDSCs may confer drug resistance due to immunomodulatory effects, and serve as a biomarker for patient stratification and decision-making prior to nCRT.

THU0458 HIGH PREVALENCE OF JOINT HYPERMOBILITY IN INFLAMMATORY BOWEL DISEASE PATIENTS WITH PAIN UNRESPONSIVE TO BOWEL-TARGETED THERAPY

Background:

Musculoskeletal manifestations occur in 20-50% of patients (pts) with inflammatory bowel disease (IBD). A substantial number of patients complain of non-inflammatory musculoskeletal pain.

Objectives:

To assess the incidence of joint hypermobility (JHM), benign joint hypermobility syndrome (BJHS) among patients with inflammatory bowel disease (IBD) examined in the inter-disciplinary rheumatology service at a tertiary referral center and the impact on IBD manifestations and outcome.

Methods:

Medical records of 180 consecutive IBD pts referred to the inter-disciplinary clinic were retrospectively reviewed. Data regarding age, gender, diagnosis, disease duration, clinical and laboratory features, previous and current therapy, Harvey-Brandshaw Index were entered into a database and analyzed. Beighton’s scoring of ≥4/9 was used to define patients with JHM. The 1998 Brighton’s criteria were used to identify patients with BJHS. Outcome was defined as improvement of joint pain. The statistical methods used included descriptive statistics, T test, Spearman’s correlation and multiple logistic regression analysis.

Results:

Forty-six patients (mean(SD) age 36.2(12.4), disease duration 13.9(8.8) years) out of 180 IBD patients (mean(SD) age 40.4(14.3), disease duration 15.7(9.1) years) fulfilled the criteria for JHM. Twelve patients had active inflammatory joint disease (2 with axial involvement, 10 with peripheral joint disease and 2 with axial and peripheral joint involvement). The other 32 answered both major criteria for BJHS. The median Beighton scoring was 7 (range 5-9). Most of them were on biological treatment. Patients with JHM suffered frequently of arthralgia and abdominal pain, in spite of endoscopic remission and normal levels of calprotectin and inflammatory markers (p=0.02, r=0.17). JHM and BJHS were associated with poorer outcome (p=0.004, r=0.2). In a multiple logistic regression analysis, only JHM reached borderline significance for predicting worse outcome.

Conclusion:

Joint and abdominal pain did not improve with immunomodulatory therapy in IBD patients with JHM. JHM may have a negative impact on achievement of clinical remission, in a significant subset of IBD patients. Rheumatologists and gastroenterologists should be aware of this.

Disclosure of Interests: :

Haya Zidany: None declared, Matti Waterman: None declared, Kohava Toledano: None declared, Yehuda Chowers: None declared, Doron Markovits: None declared, Amir Karban: None declared, Alexandra Balbir-Gurman Consultant of: Novartis, Yolanda Braun-Moscovici: None declared

Does early corticosteroid therapy affect prognosis in IBD patients hospitalized with Clostridioides difficile infection?

BACKGROUND

Corticosteroids (CS) therapy to Clostridioides difficile infection (CDI) in inflammatory bowel disease (IBD) flares may worsen CDI outcomes.

AIM

Assess the impact of early CS exposure on outcomes of IBD patients diagnosed with CDI.

METHODS

Retrospective study of IBD patients admitted with first-time CDI between 2002 and 2018. Comparisons were made based on CS exposure 48 h from admission. Patients were further subdivided to 5 groups based on CS-antibiotics temporal exposure. The primary outcome was all-cause mortality or colectomy within 3 months. Secondary outcomes were colectomy and mortality rates at 1 year, length of stay, readmissions, bacteremia, and diarrhea improvement by day 7/discharge. Cox proportional hazard model and Kaplan-Meier curves were used to assess the effects on survival. Logistic and ordinal regressions were used to assess primary and secondary outcomes.

RESULTS

One hundred thirteen patients (64 CD, 46 UC, and 3 IBDU) were included, 82 (72.5%) received early CS. At baseline, CRP was significantly lower and albumin was higher in the group not exposed to early CS. At 3 months, 4 (4.8%) patients required colectomy and 6 (5.8%) died (p = NS). Length of stay was significantly reduced among patients not exposed to early CS. All other endpoints were not associated with CS exposure. In subgroup analysis, the primary outcome was not significantly different among the sub-groups. Mortality rate at 1 year was significantly lower in patients who did not receive antibiotics for CDI.

CONCLUSION

Early CS therapy in IBD patients hospitalized with CDI is not associated with worse clinical outcomes. However, additional prospective research is required.

Safety and effectiveness of ustekinumab for induction of remission in patients with Crohn's disease: A multicenter Israeli study

INTRODUCTION

Ustekinumab is an effective treatment of Crohn's disease (CD). Real-world data addressing the efficacy and safety of ustekinumab are scarce.

AIM

Our aim was to assess the safety and efficacy of ustekinumab in a large national patient cohort.

METHODS

A prospective multicenter study, in which we followed patients with active CD treated with ustekinumab for 24 weeks. Induction dose was intravenous ranging from 260 to 520 mg, according to body weight, followed by 90 mg doses given subcutaneously every 8 weeks. Clinical response was defined as a reduction of at least 1 severity category, as defined by Harvey-Bradshaw index (HBI). Patients with HBI < 5 were considered to be in clinical remission. Patients who stopped needing steroids at week 24 were defined as being in steroid-free clinical remission.

RESULTS

A total of 106 CD patients from eight Israeli centers were included. All patients were previously exposed to at least one biological agent. Our cohort consisted of 65 (61.3%) females. Mean age was 41 ± 14 years with an average disease duration of 12.2 ± 8 years. A total of 96 (90.5%) patients continued treatment throughout week 24. Clinical response was observed in 52% of these patients with mean HBI reduction from 8.34 ± 3.8 to 6.8 ± 4.4 at week 24 (p = 0.001). Clinical remission was achieved in 33 patients (31.1%). Moreover, the number of patients requiring steroid treatment was reduced by 66% at week 24. Out of 106 patients, 11 patients (10.4%) discontinued treatment: 3 due to adverse events (2.8%), 7 due to a lack of response, and 1 who was lost to follow-up. Following 24 weeks of treatment, 15 patients reported minor adverse events.

CONCLUSIONS

In a large real-world Israeli cohort of non-naïve-to-biological-treatment CD patients, ustekinumab was effective and safe in induction of clinical remission with a significant reduction in the number of patients requiring steroid treatment.

Regulation of S100A8 Stability by RNF5 in Intestinal Epithelial Cells Determines Intestinal Inflammation and Severity of Colitis

Inflammatory bowel disease (IBD) is prevalent, but the mechanisms underlying disease development remain elusive. We identify a role for the E3 ubiquitin ligase RNF5 in IBD. Intestinal epithelial cells (IECs) express a high level of RNF5, while the colon of Rnf5^−/− mice exhibits activated dendritic cells and intrinsic inflammation. Rnf5^−/− mice exhibit severe acute colitis following dextran sodium sulfate (DSS) treatment. S100A8 is identified as an RNF5 substrate, resulting in S100A8 ubiquitination and proteasomal-dependent degradation that is attenuated upon inflammatory stimuli. Loss of RNF5 from IECs leads to enhanced S100A8 secretion, which induces mucosal CD4⁺ T cells, resulting in Th1 pro-inflammatory responses. Administration of S100A8-neutralizing antibodies to DSS-treated Rnf5^−/− mice attenuates acute colitis development and increases survival. An inverse correlation between RNF5 and S100A8 protein expression in IECs of IBD patients coincides with disease severity. Collectively, RNF5-mediated regulation of S100A8 stability in IECs is required for the maintenance of intestinal homeostasis.

Fujita et al. show that RNF5 regulation of S100A8 stability in intestinal epithelial cells defines the degree of pro-inflammatory response, culminating in severe intestinal inflammation following DSS treatment to Rnf5^−/− mice. Neutralizing S100A8 antibodies attenuates acute colitis phenotypes, and inverse RNF5/S100A8 expression coincides with clinical severity in IBD patients.

Infliximab-Tumor Necrosis Factor Complexes Elicit Formation of Anti-Drug Antibodies

BACKGROUND & AIMS

Some patients develop anti-drug antibodies (ADAs), which reduce the efficacy of infliximab, a monoclonal antibody against tumor necrosis factor (TNF), in the treatment of immune-mediated diseases, including inflammatory bowel diseases. ADAs arise inconsistently, and it is not clear what factors determine their formation. We investigated features of the immune system, the infliximab antibody, and its complex with TNF that might contribute to ADA generation.

METHODS

C57BL/6 mice were given injections of infliximab and recombinant human TNF or infliximab F(ab')₂ fragments. Blood samples were collected every 2-3 days for 2 weeks and weekly thereafter for up to 6 weeks; infliximab-TNF complexes and ADAs were measured by enzyme-linked immunosorbent assay (ELISA). Intestinal biopsy and blood samples were obtained from patients having endoscopy who had received infliximab therapy for inflammatory bowel diseases; infliximab-TNF complexes were measured with ELISA. Infliximab-specific plasma cells were detected in patient tissue samples by using mass cytometry. We studied activation of innate immune cells in peripheral blood mononuclear cells (PBMCs) from healthy donors incubated with infliximab or infliximab-TNF complexes; toll-like receptors (TLRs) were blocked with antibodies, endocytosis was blocked with the inhibitor PitStop2, and cytokine expression was measured by real-time polymerase chain reaction and ELISAs. Uptake of infliximab and infliximab-TNF complexes by THP-1 cells was measured with confocal microscopy.

RESULTS

Mice given increasing doses of infliximab produced increasing levels of ADAs. Blood samples from mice given injections of human TNF and infliximab contained infliximab-TNF complexes; complex formation was associated with ADA formation with an area under the curve of 0.944 (95% confidence interval, 0.851-1.000; P = .003). Intestinal tissues from patients, but not blood samples, contained infliximab-TNF complexes and infliximab-specific plasma cells. Incubation of PBMCs with infliximab-TNF complexes resulted in a 4.74-fold increase in level of interleukin (IL) 1β (IL1B) messenger RNA (P for comparison = .005), increased IL1B protein secretion, and a 2.69-fold increase in the expression of TNF messenger RNA (P for comparison = 0.013) compared with control PBMCs. Infliximab reduced only IL1B and TNF expression. Antibodies against TLR2 or TLR4 did not block the increases in IL1B or TNF expression, but endocytosis was required. THP-1 cells endocytosed higher levels of infliximab-TNF complexes than infliximab alone.

CONCLUSIONS

In mice, we found ADA formation to increase with dose of infliximab given and concentration of infliximab-TNF complexes detected in blood. Based on studies of human intestinal tissues and blood samples, we propose that infliximab-TNF complexes formed in the intestine are endocytosed by and activate innate immune cells, which increase expression of IL1B and TNF and production of antibodies against the drug complex. It is therefore important to optimize the infliximab dose to a level that is effective but does not activate an innate immune response against the drug-TNF complex.

One Size Does Not Fit All: The Case for Translational Medicine

Therapy for inflammatory bowel diseases (IBD) has developed during recent years. Despite the availability of new therapeutic modalities, overall therapy success remains modest, and complete remission is usually achieved and maintained in approximately 30% of patients only. This observation can be explained by a number of reasons. First, the involvement of multiple genetic loci combined with differential environmental exposures suggests that IBD represent a continuum of disorders rather than distinct homogeneous disease entities. This diversity is translated into different disease course patterns, wherein some patients experience quiescent disease whereas others suffer from a relentless disease course. Hence, basic disease pathogenesis sets the stage for differential treatment responses. To date, IBD therapy is based on immunosuppression which does not take basic disease variability into account. Treatments are prescribed based on statistical considerations related to the response of the average patient in clinical trials rather than on personal considerations. Treatment outcomes can potentially be improved if physiologic considerations are integrated into the drug selection process. In one approach, drugs can be targeted at known patient dysfunctional processes such as in the case of patients carrying autophagy-related genetic polymorphisms being treated with rapamycin, a drug that inhibits mTOR inhibitor and enhances autophagy. Another alternative would be to use a systems approach to perform unsupervised, high-throughput screening in order to derive predictive treatment biomarkers and mechanistic insights associated with response to specific drug therapy. Additional predictive markers for drug safety are needed as well. Caveats and directions for needed future studies are outlined.

Cell-centred meta-analysis reveals baseline predictors of anti-TNFα non-response in biopsy and blood of patients with IBD

OBJECTIVE

Although anti-tumour necrosis factor alpha (anti-TNFα) therapies represent a major breakthrough in IBD therapy, their cost-benefit ratio is hampered by an overall 30% non-response rate, adverse side effects and high costs. Thus, finding predictive biomarkers of non-response prior to commencing anti-TNFα therapy is of high value.

DESIGN

We analysed publicly available whole-genome expression profiles of colon biopsies obtained from multiple cohorts of patients with IBD using a combined computational deconvolution-meta-analysis paradigm which allows to estimate immune cell contribution to the measured expression and capture differential regulatory programmes otherwise masked due to variation in cellular composition. Insights from this in silico approach were experimentally validated in biopsies and blood samples of three independent test cohorts.

RESULTS

We found the proportion of plasma cells as a robust pretreatment biomarker of non-response to therapy, which we validated in two independent cohorts of immune-stained colon biopsies, where a plasma cellular score from inflamed biopsies was predictive of non-response with an area under the curve (AUC) of 82%. Meta-analysis of the cell proportion-adjusted gene expression data suggested that an increase in inflammatory macrophages in anti-TNFα non-responding individuals is associated with the upregulation of the triggering receptor expressed on myeloid cells 1 (TREM-1) and chemokine receptor type 2 (CCR2)-chemokine ligand 7 (CCL7) -axes. Blood gene expression analysis of an independent cohort, identified TREM-1 downregulation in non-responders at baseline, which was predictive of response with an AUC of 94%.

CONCLUSIONS

Our study proposes two clinically feasible assays, one in biopsy and one in blood, for predicting non-response to anti-TNFα therapy prior to initiation of treatment. Moreover, it suggests that mechanism-driven novel drugs for non-responders should be developed.

Efficacy of biological drugs in short-duration versus long-duration inflammatory bowel disease: a protocol for a systematic review and an individual-patient level meta-analysis of randomised controlled trials

INTRODUCTION

Crohn's disease (CD) and ulcerative colitis (UC) are remitting-relapsing inflammatory diseases often culminating in disease complications and/or need for surgery. Biologic monoclonal antibody drugs ('Biologics') are efficacious for both diseases, but there are no systematic assessments of their efficacy if administered early after disease onset ('top-down' strategy) vis-à-vis later in the course of disease ('step-up' approach).

METHODS AND ANALYSIS

Electronic databases (MEDLINE, EMBASE/EMBASE classic Cochrane CENTRAL register of controlled trials, the Cochrane IBD Group Specialised Trials Register and Clinicaltrials.gov registry) will be searched to identify all randomised placebo-controlled clinical trials of food and drug administration (FDA)-approved biologics for CD and UC (by March 2016). Two independent reviewers will screen identified papers, extract data and assess the risk of bias according to the Cochrane Handbook for Systematic Reviews of Interventions. Individual-patient-level data (IPD) will be extracted from the identified trials through data-sharing platforms for pharmaceutical companies' sponsored trials and by contacting principal investigators of independent investigator-initiated trials. We will analyse induction of remission in patients with early-disease (<18 months since disease onset) versus patients with longer disease duration, using a generalised linear mixed effect model and by a two-stage approach using coefficient for the treatment-by-subgroup interaction within each trial. We will perform receiver operator curve analysis of optimal disease duration for response. Analyses will be separate for CD and UC. This first-of-its-kind meta-analysis at IPD level of interaction of disease duration with the response to biologics in UC and CD may elucidate the impact of early initiation of biologics, which is of paramount importance for clinical practice and management strategies of inflammatory bowel disease.

ETHICS AND DISSEMINATION

This meta-analysis was approved by the Ethics Committee of the First Affiliated Hospital of Sun Yat-sen University. Findings will be published in peer-reviewed journal and disseminated via scientific meetings and links with organisations.

PROSPERO REGISTRATION NUMBER

CRD42018041961.

Pharmacokinetics and Immune Reconstitution Following Discontinuation of Thiopurine Analogues: Implications for Drug Withdrawal Strategies

BACKGROUND AND AIMS

Discontinuation of thiopurine analogues is common prior to live vaccines, during infection or when de-escalating therapy. Data regarding clearance of active metabolites and immune re-constitution is scant. We aimed to determine drug elimination and immune re-constitution following thiopurine cessation.

METHODS

The elimination kinetics of 6-thioguanine nucleotides (6-TGN) were determined in nine inflammatory bowel disease [IBD] patients discontinuing thiopurines. Immune reconstitution was evaluated by toxic shock syndrome toxin 1 [TSST1] or anti-CD3 [OKT3]-induced CD4+ T-cell proliferation, following an initial exposure to TSST1 and 6-mercaptopurine [6MP], separately or combined.

RESULTS

All patients discontinuing thiopurines displayed first-order elimination kinetics of 6-TGN, with a median elimination half-life of 6.8 days [interquartile range 5.9-8.4]. Resting CD4+ T-cells exposed to 6MP preserved their response to subsequent polyclonal or Vβ2+-preferential stimulation. By contrast, exposure of TSST1-activated CD4+ T-cells to 6MP inhibited their subsequent Vβ2+clonal response to further stimulation [p = 0.008], whereas overall response to further non-Vβ2-selective stimulation with OKT3 was unaltered [p = 0.9].

CONCLUSIONS

Upon 6MP/azathioprine discontinuation, a 6-TGN elimination half-life of less than 10 days is expected in most patients. Immune reconstitution, however, may take longer for T-cell clones exposed to stimulation during thiopurine treatment. These findings may be useful when considering thiopurine cessation.

Development and validation of novel algorithms to identify patients with inflammatory bowel diseases in Israel: an epi-IIRN group study

Background

Before embarking on administrative research, validated case ascertainment algorithms must be developed. We aimed at developing algorithms for identifying inflammatory bowel disease (IBD) patients, date of disease onset, and IBD type (Crohn's disease [CD] vs ulcerative colitis [UC]) in the databases of the four Israeli Health Maintenance Organizations (HMOs) covering 98% of the population.

Methods

Algorithms were developed on 5,131 IBD patients and 2,072 controls, following independent chart review (60% CD and 39% UC). We reviewed 942 different combinations of clinical parameters aided by mathematical modeling. The algorithms were validated on an independent cohort of 160,000 random subjects.

Results

The combination of the following variables achieved the highest diagnostic accuracy: IBD-related codes, alone if more than five to six codes or combined with purchases of IBD-related medications (at least three purchases or ≥3 months from the first to last purchase) (sensitivity 89%, specificity 99%, positive predictive value [PPV] 92%, negative predictive value [NPV] 99%). A look-back period of 2-5 years (depending on the HMO) without IBD-related codes or medications best determined the date of diagnosis (sensitivity 83%, specificity 68%, PPV 82%, NPV 70%). IBD type was determined by the majority of CD/UC codes of the three recent contacts or the most recent when less than three contacts were recorded (sensitivity 92%, specificity 97%, PPV 97%, NPV 92%). Applying these algorithms, a total of 38,291 IBD patients were residing in Israel, corresponding to a prevalence rate of 459/100,000 (0.46%).

Conclusion

The application of the validated algorithms to Israel's administrative databases will now create a large and accurate ongoing population-based cohort of IBD patients for future administrative studies.

Association of Vedolizumab Level, Anti-Drug Antibodies, and α4β7 Occupancy With Response in Patients With Inflammatory Bowel Diseases

BACKGROUND & AIMS

There are few data available on the real-life pharmacokinetic and pharmacodynamics features of vedolizumab, a monoclonal antibody against integrin α4β7. We performed a prospective study of patients with inflammatory bowel diseases (IBDs) treated with vedolizumab to determine serum drug concentrations, formation of antivedolizumab antibodies (AVAs), and integrin α4β7 saturation.

METHODS

We performed a prospective study of 106 patients with IBD (67 with Crohn's disease and 39 with ulcerative colitis) treated with vedolizumab from September 2014 through March 2017 at 2 tertiary medical centers in Israel. Clinical data and serum samples were collected before and during induction and maintenance therapy. Clinical remission was defined as Harvey-Bradshaw index scores below 5 or as Simple Clinical Colitis Activity Index scores of 3 or less. We measured serum levels of vedolizumab, AVAs, and markers of inflammation. Peripheral blood mononuclear cells were obtained from some patients at designated trough time points and CD3+ CD45RO+ T cells were isolated from 36 samples. Cells were incubated with fluorescent-conjugated vedolizumab and flow cytometry was used to quantify α4β7 integrin saturation. We also performed flow cytometry analyses of CD3+ CD45RO+ lamina propria T cells isolated from intestinal mucosa of patients without IBD (non-IBD controls, n = 6), patients with IBD not treated with vedolizumab (untreated IBD controls, n = 8), and patients with IBD treated with vedolizumab (n = 15).

RESULTS

Clinical remission was achieved by 48 of 106 patients (45%) by week 6 and 50 of 106 patients (48%) by week 14 of treatment. The median level of vedolizumab at week 6 was higher in patients in clinical remission (40.2 μg/mL) than in patients with active disease (29.7 μg/mL; P = .05). The median serum level of vedolizumab was significantly higher in patients with a normal level of C-reactive protein (21.8 μg/mL vedolizumab) vs the level in those with a high level of C-reactive protein (11.9 μg/mL vedolizumab) during maintenance treatment (P = .0006). The other clinical outcomes measured were not associated with median serum level of vedolizumab at any time point examined. AVAs were detected in 17% of patients during induction therapy and 3% of patients during maintenance therapy, but did not correlate with clinical outcomes. Flow-cytometry analysis of peripheral blood memory T cells (n = 36) showed near-complete occupancy of α4β7 integrin at weeks 2 and 14 and during the maintenance phase, regardless of response status or drug levels. Most intestinal CD3+CD45RO+ memory T cells of healthy and IBD controls expressed α4β7 (72%; interquartile range, 56%-81%). In contrast, free α4β7 was detectable on only 5.6% of intestinal memory cells (interquartile range, 4.4%-11.2%) (P < .0001) from vedolizumab-treated patients, regardless of response.

CONCLUSIONS

In a prospective study of real-life patients with IBD, we associated vedolizumab drug levels with remission and inflammatory marker level. Integrin α4β7 was blocked in almost all T cells from patients treated with vedolizumab, regardless of serum level of the drug or response to treatment. These findings indicate a need to explore alternative mechanisms that prevent response to vedolizumab.

Early drug and anti-infliximab antibody levels for prediction of primary nonresponse to infliximab therapy

BACKGROUND

Primary nonresponse, defined as lack of clinical benefit during the induction phase, occurs in up to 30% of IBD patients treated with infliximab. The mechanisms underlying primary nonresponse have not yet been clearly defined.

AIM

To evaluate the association of early (week 2 and week 6) induction infliximab and anti-infliximab antibody levels with primary nonresponse.

METHODS

A retrospective observational case-control study of inflammatory bowel disease patients treated with infliximab and followed at Sheba Medical Center between 2009 and 2016 was performed. Pre-infusion infliximab and antibodies to infliximab (ATI) levels were measured by our previously described drug-tolerant ELISA assay.

RESULTS

Thirty-five primary nonresponders have been identified and matched with 105 primary responders (1:3 ratios). Both week 2 and week 6 infliximab levels were significantly lower among primary nonresponders compared to responders (week 2, 6: median level 7.2, 2.2 μg/mL vs 13.5, 9.5 μg/mL, P = .0019, P < .0001 respectively). Antibodies to infliximab appeared more frequently (either week 2 or 6, 68% vs 28% prevalence, P = .0004) and at higher levels in nonresponders compared to responders (week 2, 6: median ATI 7.3, 10.8 μg/mL-eq vs 3.8, 4.4 μg/mL-eq, P = .005, P = .008 respectively). Moreover, week 2 infliximab levels <6.8 μg/mL (AUC = 0.68, P = .002, sensitivity 50%, specificity 86%) and antibodies to infliximab levels >4.3 μg/mL-eq (AUC = 0.78, P = .0004, sensitivity 77%, specificity 71%) were predictive of primary nonresponse. Among the other clinical and demographic variables, higher baseline ulcerative colitis clinical score, infliximab monotherapy, prior adalimumab therapy and previous Crohn's disease-related surgeries were also associated with an increased risk of primary nonresponse.

CONCLUSIONS

Infliximab levels below 6.8 μg/mL and antibodies to infliximab levels above 4.3 μg/mL-eq before the second infusion are associated with primary nonresponse, especially among Crohn's disease patients.

Radiation induces proinflammatory dysbiosis: transmission of inflammatory susceptibility by host cytokine induction

OBJECTIVE

Radiation proctitis (RP) is a complication of pelvic radiotherapy which affects both the host and microbiota. Herein we assessed the radiation effect on microbiota and its relationship to tissue damage using a rectal radiation mouse model.

DESIGN

We evaluated luminal and mucosa-associated dysbiosis in irradiated and control mice at two postradiation time points and correlated it with clinical and immunological parameters. Epithelial cytokine response was evaluated using bacterial-epithelial co-cultures. Subsequently, germ-free (GF) mice were colonised with postradiation microbiota and controls and exposed to radiation, or dextran sulfate-sodium (DSS). Interleukin (IL)-1β correlated with tissue damage and was induced by dysbiosis. Therefore, we tested its direct role in radiation-induced damage by IL-1 receptor antagonist administration to irradiated mice.

RESULTS

A postradiation shift in microbiota was observed. A unique microbial signature correlated with histopathology. Increased colonic tumor necrosis factor (TNF)α, IL-1β and IL-6 expression was observed at two different time points. Adherent microbiota from RP differed from those in uninvolved segments and was associated with tissue damage. Using bacterial-epithelial co-cultures, postradiation microbiota enhanced IL-1β and TNFα expression compared with naïve microbiota. GF mice colonisation by irradiated microbiota versus controls predisposed mice to both radiation injury and DSS-induced colitis. IL-1 receptor antagonist administration ameliorated intestinal radiation injury.

CONCLUSIONS

The results demonstrate that rectal radiation induces dysbiosis, which transmits radiation and inflammatory susceptibility and provide evidence that microbial-induced radiation tissue damage is at least in part mediated by IL-1β. Environmental factors may affect the host via modifications of the microbiome and potentially allow for novel interventional approaches via its manipulation.

[OPTIMIZATION OF TREATMENT BY ANTIBODIES AGAINST TNF-α IN INFLAMMATORY BOWEL DISEASE]

Treatment selection for inflammatory bowel disease involves many considerations. Anti-TNF - α agents are one of the major available therapeutic tools for these diseases. Loss of response to anti- TNF - α agents is relatively common and results mostly, but not exclusively, from the development of immunogenicity against the drug. Assessment of disease activity in parallel to measurement of drug levels and anti-drug antibodies allows for treatment optimization in patients who develop clinical loss of response. For patients in remission, treatment optimization can be performed by the evaluation of risk factors for disease flare assisted by assessment of drug levels and the presence of antibodies. Various algorithms can be used to make a decision that will lead to better clinical outcomes and a better cost-effectiveness ratio. Professor Yehuda Chowers has received consultancy fees from Abbot and Schering-Plough.

Association of Induction Infliximab Levels With Clinical Response in Perianal Crohn's Disease

BACKGROUND

The association of infliximab [IFX] trough levels with clinical and endoscopic outcomes in inflammatory bowel disease is well established. However, there is scarce data regarding the association of perianal fistula response with IFX. The aim of this study was to establish whether early induction infliximab levels and anti-infliximab antibodies [ATIs] are associated with perianal fistula response.

METHODS

Consecutive CD patients with perianal fistulae that were treated with IFX between 2008 and 2016 were included in the study. Response was defined as cessation or significant improvement of fistula drainage. Patients with unavailable IFX level or ATI measurements and/or missing clinical follow-up at Week 14 were excluded.

RESULTS

A total of 36 patients with perianal fistulae were included; 25/36 [69.4%] responded to treatment by Week 14. The median induction IFX levels at Weeks 2, 6 and 14 in the responders group at Week 14 were higher compared with those of the non-responders group [20/5.6 µg/mL, P = 0.0001; 13.3/2.55 µg/mL P = 0.0001; 4.1/0.14 µg/mL, P = 0.01]. On multivariate analysis, IFX leve at Weeks 2 and 6 were significantly associated with fistula response at Weeks 14 and 30. IFX drug levels of 9.25 µg/mL at Week 2 and 7.25 µg/mL at Week 6 were the best predictors of fistula response.

CONCLUSION

High IFX trough levels during induction are associated with favorable fistula response to anti-TNF treatment. If validated in a larger prospective study, our findings may help guide anti-TNF treatment in patients with perianal CD, and suggest serum level-guided treatment escalation in non-responders or prompt changing of biologic treatment in non-responders.

Differentiation of Pancreatic Cyst Types by Analysis of Rheological Behavior of Pancreatic Cyst Fluid

Differentiation between mucinous and non-mucinous pancreatic cysts is exceedingly important and challenging, particularly as the former bears malignant transformation potential. Pancreatic cyst fluid (PCF)-based diagnostics, including analyses of biochemical markers, as well as cytology, has shown inadequate accuracy. Herein, a preliminary single-center study of 22 PCF samples, collected by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA), assessed the rheological behavior of PCF and its correlation with lesion type. The dependence of PCF shear viscosity on shear rate was found to follow a power law and could be fitted using Ostwald-de Waele model. Three types of flow curves were identified, where two types correlated with non-mucinous cysts, differing by their power law exponent, and the third type corresponding to mucinous cysts. Viscosity measured at a high shear rate was shown to serve as an accurate and independent marker distinguishing between mucinous and non-mucinous cysts, with an optimal cutoff value of ηc = 1.3 cP The accuracy of this novel technique proved superior to string-sign, cytology, carcinoembryonic antigen, and amylase assessments. Moreover, the combined predictive value of ηc and patient age provided for sensitivity and specificity of 100% and 95.5%, respectively. This simple and rapid diagnostic tool can be immediately implemented after EUS-FNA sampling.

The Heparanase Inhibitor PG545 Attenuates Colon Cancer Initiation and Growth, Associating with Increased p21 Expression

Heparanase activity is highly implicated in cellular invasion and tumor metastasis, a consequence of cleavage of heparan sulfate and remodeling of the extracellular matrix underlying epithelial and endothelial cells. Heparanase expression is rare in normal epithelia, but is often induced in tumors, associated with increased tumor metastasis and poor prognosis. In addition, heparanase induction promotes tumor growth, but the molecular mechanism that underlines tumor expansion by heparanase is still incompletely understood. Here, we provide evidence that heparanase down regulates the expression of p21 (WAF1/CIP1), a cyclin-dependent kinase inhibitor that attenuates the cell cycle. Notably, a reciprocal effect was noted for PG545, a potent heparanase inhibitor. This compound efficiently reduced cell proliferation, colony formation, and tumor xenograft growth, associating with a marked increase in p21 expression. Utilizing the APC Min^+/− mouse model, we show that heparanase expression and activity are increased in small bowel polyps, whereas polyp initiation and growth were significantly inhibited by PG545, again accompanied by a prominent induction of p21 levels. Down-regulation of p21 expression adds a novel feature for the emerging pro-tumorigenic properties of heparanase, while the potent p21 induction and anti-tumor effect of PG545 lends optimism that it would prove an efficacious therapeutic in colon carcinoma patients.

Prevention of Antidrug Antibody Formation to Infliximab in Crohn's Patients With Prior Failure of Thiopurines

BACKGROUND & AIMS

Combination thiopurine-infliximab (IFX) therapy is associated with reduced generation of antidrug antibodies (ADA) compared with IFX monotherapy. Whether past clinical response to thiopurine therapy bears an effect on ADA prevention is unknown.

METHODS

This was a retrospective observational multicenter study of patients with Crohn's disease (CD) treated by IFX and thiopurines who had serial ADA measurements. Therapy was classified into past thiopurine response or its lack of, de novo combination, or IFX monotherapy. The primary endpoint was risk of ADA appearance.

RESULTS

Out of 494 patients with serial ADA measurements 207 eligible patients were included in the final analysis. The 1-year cumulative risk of ADA development was similar in past thiopurine responders (19.3%) compared with past thiopurine failures (16.1%) (log rank P = .54). ADA was found in 46.6% of the monotherapy group and was significantly different compared with past thiopurine responders (P = .007) and past thiopurine failures (P = .007). The adjusted hazards for ADA development were significantly lower in past responders and past failures compared with the monotherapy group (hazard ratio, 0.47 [95% CI, 0.22-1.00] and 0.32 [95% CI, 0.11-0.93], respectively).

CONCLUSIONS

Thiopurines-IFX cotherapy in patients with Crohn's disease is associated with reduced ADA formation compared with IFX monotherapy. This is probably regardless of initial thiopurine therapeutic effect.

3rd European Evidence-based Consensus on the Diagnosis and Management of Crohn's Disease 2016: Part 1: Diagnosis and Medical Management

This paper is the first in a series of two publications relating to the European Crohn's and Colitis Organisation [ECCO] evidence-based consensus on the diagnosis and management of Crohn's disease and concerns the methodology of the consensus process, and the classification, diagnosis and medical management of active and quiescent Crohn's disease. Surgical management as well as special situations including management of perianal Crohn's disease of this ECCO Consensus are covered in a subsequent second paper [Gionchetti et al JCC 2016].

Addition of an immunomodulator can reverse antibody formation and loss of response in patients treated with adalimumab

BACKGROUND

Anti-adalimumab antibodies (AAA) are associated with loss of clinical response (LOR). Addition of an immunomodulator has been shown to reverse immunogenicity and regain response with infliximab monotherapy. Similar data on adalimumab are lacking.

AIM

To study the impact of immunomodulator addition on the emergence of AAA and LOR among adalimumab therapy patients.

METHODS

The databases of three tertiary medical centres were reviewed to identify patients who developed AAA during adalimumab monotherapy with resultant LOR, and received an immunomodulator as a salvage combination therapy. All sera were prospectively analysed using previously described ELISA assays. Clinical response was determined using appropriate clinical scores. Elimination of AAA, designated as 'sero-reversal', elevation of drug levels and regained clinical response were the sought outcomes.

RESULTS

Twenty-three patients (21 Crohn's disease, and 2 ulcerative colitis) developed AAA with subsequent LOR and were thereafter prescribed an immunomodulator as salvage therapy (thiopurine n = 14, methotrexate n = 9). Eleven patients (48%) underwent sero-reversal with gradual elimination of AAA, increase in drug trough levels and restoration of clinical response (median time to sero-reversal 5 months). In 12 patients (52%), immunogenicity and loss of response could not be reversed. There was no difference between responders and nonresponders in the type of immunomodulators used or baseline clinical characteristics.

CONCLUSIONS

In almost half of inflammatory bowel disease patients developing anti-adalimumab antibodies and loss of response, established immunogenicity of adalimumab can be gradually reversed by the addition of immunomodulator therapy with restoration of a clinico-biological response. However, these observations need to be confirmed with larger studies.

Addition of an immunomodulator can reverse antibody formation and loss of response in patients treated with adalimumab

BACKGROUND

Anti-adalimumab antibodies (AAA) are associated with loss of clinical response (LOR). Addition of an immunomodulator has been shown to reverse immunogenicity and regain response with infliximab monotherapy. Similar data on adalimumab are lacking.

AIM

To study the impact of immunomodulator addition on the emergence of AAA and LOR among adalimumab therapy patients.

METHODS

The databases of three tertiary medical centres were reviewed to identify patients who developed AAA during adalimumab monotherapy with resultant LOR, and received an immunomodulator as a salvage combination therapy. All sera were prospectively analysed using previously described ELISA assays. Clinical response was determined using appropriate clinical scores. Elimination of AAA, designated as 'sero-reversal', elevation of drug levels and regained clinical response were the sought outcomes.

RESULTS

Twenty-three patients (21 Crohn's disease, and 2 ulcerative colitis) developed AAA with subsequent LOR and were thereafter prescribed an immunomodulator as salvage therapy (thiopurine n = 14, methotrexate n = 9). Eleven patients (48%) underwent sero-reversal with gradual elimination of AAA, increase in drug trough levels and restoration of clinical response (median time to sero-reversal 5 months). In 12 patients (52%), immunogenicity and loss of response could not be reversed. There was no difference between responders and nonresponders in the type of immunomodulators used or baseline clinical characteristics.

CONCLUSIONS

In almost half of inflammatory bowel disease patients developing anti-adalimumab antibodies and loss of response, established immunogenicity of adalimumab can be gradually reversed by the addition of immunomodulator therapy with restoration of a clinico-biological response. However, these observations need to be confirmed with larger studies.

Detection of anti-infliximab antibodies is impacted by antibody titer, infliximab level and IgG4 antibodies: a systematic comparison of three different assays

BACKGROUND

There is scant information on the accuracy of different assays used to measure anti-infliximab antibodies (ADAs), especially in the presence of detectable infliximab (IFX). We thus aimed to evaluate and compare three different assays for the detection of IFX and ADAs and to clarify the impact of the presence of circulating IFX on the accuracy of the ADA assays.

METHODS

Blood samples from 79 ulcerative colitis (UC) patients treated with infliximab were assessed for IFX levels and ADAs using three different assays: an in-house assay and two commercial kits, Immundiagnostik and Theradiag. Sera samples with ADAs and undetectable levels of IFX were spiked with exogenous IFX and analyzed for ADAs.

RESULTS

The three assays showed 81-96% agreement for the measured IFX level. However, the in-house assay and Immundiagnostik assays detected ADAs in 34 out of 79 samples, whereas Theradiag only detected ADAs in 24 samples. Samples negative for ADAs with Theradiag, but ADA-positive in both the in-house and Immundiagnostik assays, were positive for IFX or IgG4 ADAs. In spiking experiments, a low concentration of exogenous IFX (5 µg/ml) hampered ADA detection with Theradiag in sera samples with ADA levels of between 3 and 10 µg/ml. In the Immundiagnostik assay detection interference was only observed at concentrations of exogenous IFX higher than 30 µg/ml. However, in samples with high levels of ADAs (>25 µg/ml) interference was only observed at IFX concentrations higher than 100 µg/ml in all three assays. Binary (IFX/ADA) stratification of the results showed that IFX+/ADA- and IFX-/ADAs+ were less influenced by the assay results than the double-positive (IFX+/ADAs+) and double-negative (IFX-/ADAs-) combination.

CONCLUSIONS

All three methodologies are equally suitable for measuring IFX levels. However, erroneous therapeutic decisions may occur when patients show double-negative (IFX-/ADAs-) or double-positive (IFX+/ADAs+) status, since agreement between assays is significantly lower in these circumstances.

Early histological findings may predict the clinical phenotype in Crohn's colitis

BACKGROUND AND AIMS

Predicting the clinical course of Crohn's disease (CD) is relevant for treatment selection. Currently, such diagnostic tools are lacking. In a previous pilot study, morphometric tissue image analysis showed promise in predicting the clinical phenotype and need for surgery. In this study, we aimed to validate our previous results on a larger cohort.

METHODS

Colonic biopsies from CD patients with colonic or ileocolonic disease and at least five years of post-biopsy clinical follow-up were analyzed. The results were used to predict post-biopsy clinical phenotypes and outcomes. Data analysis was performed using multivariate regression models, discriminant score (DS) computations and Neural Network (NNET).

RESULTS

Multivariate analysis of morphometric variables differentiated between B1 and B2 phenotypes (sensitivity 81%, specificity 74%, accuracy on cross-validation 75%; area under the curve (AUC) of 0.74 (CI 0.6-0.84; NNET model sensitivity 87%, specificity 67% on the testing population)). Differentiation between B1 and B3 phenotypes was also possible (sensitivity 69%, specificity 76%, accuracy 70.5% on cross-validation; AUC 0.78 (CI 0.68-0.89); NNET model sensitivity 78%, specificity 77% on the testing population)). Differentiating between B2 and B3 phenotypes was not possible using morphometric variables. Multivariate analysis predicted surgery (sensitivity 67%, specificity 72.5%, accuracy 69%; AUC 0.72 (CI 0.61-0.82); NNET model sensitivity 80%, specificity 91% on the testing population)).

CONCLUSIONS

This study validates previous results and suggests that morphometric image analysis of early biopsies from Crohn's colitis patients may contribute to the prediction of future outcomes such as clinical phenotype and surgery. Prospective validation on larger cohorts is still needed.

Discovery of Biomarkers of Response in Early Drug Development

Ulcerative colitis and Crohn's disease have traditionally been managed by incrementally stepping up within a hierarchy of therapeutic classes consequent to failing a given therapeutic─necessitated by the notion that any type of therapeutic will only induce clinical response and remission in a fraction of, but not all, patients. Hence, the selection of therapies approximates stage of disease rather than patient-specific characteristics that would allow selection of a specific mechanism of action for therapeutic intervention. Development of prognostic biomarkers [to identify patients with more aggressive disease and a worse prognosis], as well as predictive biomarkers [to predict response or non-response to a particular therapy], has been identified as a key requirement for attainment of better overall response rates or to improve the response of the most severely ill patient subgroup. Since the state of biomarker development is early and the process in inflammatory bowel disease appears more complex than in other therapeutic areas such as oncology, profiling of potential biomarkers across broad populations of undifferentiated patients will be important in refining current hypotheses and progressing their study and validation.

Magnetic resonance enterography versus capsule endoscopy activity indices for quantification of small bowel inflammation in Crohn's disease

BACKGROUND

Video capsule endoscopy (VCE) and magnetic resonance enterography (MRE) are the prime modalities for the evaluation of small bowel (SB) Crohn's disease (CD). Mucosal inflammation on VCE is quantified using the Lewis score (LS). Diffusion-weighted (DW) magnetic resonance imaging (MRI) allows for accurate assessment of SB inflammation without administration of intravenous contrast material. The Magnetic Resonance Index of Activity (MaRiA) and the Clermont index are quantitative activity indices validated for contrast-enhanced MRE and DW-MRE, respectively. The aim of this study was to compare the quantification of distal SB inflammation by VCE and MR-related activity indices.

METHODS

Patients with known quiescent SB CD were prospectively recruited and underwent MRE and VCE. LS, MaRIA and Clermont scores were calculated for the distal SB.

RESULTS

Both MRI-based indices significantly correlated with the LS and the Clermont index (r = 0.50, p = 0.001 and r = 0.53, p = 0.001, respectively). Both MaRIA and Clermont scores were significantly lower in patients with mucosal healing (LS < 135). The area under the curve (AUC) with both MR scores was moderate for prediction of any mucosal inflammation (LS ⩾ 135) and excellent for prediction of moderate-to-severe inflammation (LS ⩾ 790) (0.71 and 0.74 versus 0.93 and 0.91 for MaRIA and Clermont score, respectively).

CONCLUSIONS

Modest correlation between VCE- and MRE-based quantitative indices of inflammation in patients with quiescent SB CD was observed. Between-modality correlation was higher in patients with endoscopically severe disease. DW-MRE gauged by Clermont score was at least as accurate as contrast-enhanced MRE for quantification of SB inflammation.