Incidence Rates for Surgery in Crohn's Disease Have Decreased: A Population-based Time-trend Analysis

BACKGROUND

Many Crohn's disease (CD) patients will undergo surgery over the course of their life. It is thought that with the introduction of disease-modifying agents like anti-TNF therapy, there would be a population-level decrease in the need for surgery. This time-trend study aimed to assess the changes in surgical rates following the induction of anti-TNF therapy.

METHODS

Adult CD patients who underwent abdominal surgery (identified by administrative coding) between January of 1996 and December of 2013 at 1 of the 4 Edmonton-area hospitals were included. Patient charts were manually reviewed to confirm diagnosis and gather demographic and disease-related data. Population-adjusted annual incidence rates for IBD surgery were calculated by dividing the number of surgeries by estimates for total population of CD patients in Edmonton. Time-trend analysis was conducted to identify change points, calculate annual percent change (APC), and associated 95% confidence intervals (CIs).

RESULTS

A total of 1410 patients with Crohn's disease underwent surgery for their disease. The surgical rate decreased by 8.4% each year (95% CI, -9.6% to -7.3%). There was a 36.2% increase in the use of anti-TNF therapy per year (95% CI, 31.3% to 41.5%). Changes in modifiable risk factors for surgery were also seen, including the proportion of active smokers decreasing by 2.2% per year (95% CI, -3.7% to -0.6%).

CONCLUSIONS

Although anti-TNF therapy seems to play a role, the decrease in surgical trends is likely multifactorial, owing to a decline in smoking trends, earlier diagnosis, earlier treatment, improved patient education, and changes in clinical practice.

Management of Inflammatory Bowel Disease Patients With Clinical Care Pathways Reduces Emergency Department Utilization

Background

Standardizing care through pathways has the potential to reduce emergency department (ED) utilization. We developed and evaluated inflammatory bowel disease (IBD) care pathways for that purpose.

Methods

Over 2014-2016, IBD patients were retrospectively stratified into those managed and not managed by pathways. Patient data were extracted, and negative binomial regression used to predict the annual number of ED visits.

Results

There was a difference of 30.7 ED visits/100 patients between managed and nonmanaged at 12 months (P < 0.001). The incidence rate ratio of total ED visits occurring annually was 0.750 (P = 0.008).

Conclusions

Management with IBD care pathways reduces ED utilization.

An overview of clinical decision support systems: benefits, risks, and strategies for success

Computerized clinical decision support systems, or CDSS, represent a paradigm shift in healthcare today. CDSS are used to augment clinicians in their complex decision-making processes. Since their first use in the 1980s, CDSS have seen a rapid evolution. They are now commonly administered through electronic medical records and other computerized clinical workflows, which has been facilitated by increasing global adoption of electronic medical records with advanced capabilities. Despite these advances, there remain unknowns regarding the effect CDSS have on the providers who use them, patient outcomes, and costs. There have been numerous published examples in the past decade(s) of CDSS success stories, but notable setbacks have also shown us that CDSS are not without risks. In this paper, we provide a state-of-the-art overview on the use of clinical decision support systems in medicine, including the different types, current use cases with proven efficacy, common pitfalls, and potential harms. We conclude with evidence-based recommendations for minimizing risk in CDSS design, implementation, evaluation, and maintenance.

Systematic Review: Non-medical Switching of Infliximab to CT-P13 in Inflammatory Bowel Disease

BACKGROUND AND AIMS

Biosimilar approval, such as Inflectra™ (CT-P13) for treating ulcerative colitis (UC) and Crohn's disease (CD), has reduced direct drug costs. Though clinicians are comfortable with biosimilar use in treatment-naïve patients, there are concerns in some jurisdictions that there are insufficient data from well-controlled trials to support non-medical switching. A systematic review, along with a critical assessment of the study design, was conducted to assess the potential impact of switching stable CD/UC patients from infliximab to CT-P13.

METHODS

A literature search using PubMed and abstracts/posters from 3 major gastroenterology conferences from 2014 to 2018 was completed. Two individual reviewers extracted data from each relevant report and compiled it into evidence tables to facilitate descriptive analyses. Key randomized trial and observational study designs were critically assessed to contextualize data relevance.

RESULTS

A total of 49 reports (3 randomized controlled trials, 40 observational trials, and 1 case series) were included. Most studies revealed no efficacy, safety, or immunogenicity concerns with non-medical switch. Limitations of supporting data include a small number of randomized controlled trials; predominance of observational studies with varying outcome assessments and lack of appropriate controls; and scarcity of research on biosimilar switch long-term effects.

CONCLUSIONS

The majority of studies suggested non-medical switch is safe. However, clinicians and regulatory bodies should be aware of differences and limitations in study designs when making inferences about the risks and benefits of switching stable IBD patients to biosimilars.

Pregnancy-Related Beliefs and Concerns of Inflammatory Bowel Disease Patients Modified After Accessing e-Health Portal

Objective

Poor inflammatory bowel disease (IBD)-specific reproductive knowledge is associated with concerns and medication noncompliance. Having shown an educational portal can improve knowledge, we evaluated its effectiveness for addressing IBD patients’ reproductive and medication concerns.

Methods

Adult IBD participants (aged 18 to 45 years) were invited to access an e-health portal providing information on heritability, fertility, surgery, pregnancy outcomes, delivery, postpartum, and breastfeeding in the context of IBD and IBD medications. At pre-, post-, and 6+-month postintervention, participants completed a questionnaire on IBD-specific pregnancy concerns, medication concerns from the Beliefs About Medicines Questionnaire (BMQ), and medication adherence via the Medication Adherence Rating Scale (MARS). The Wilcoxon signed-rank test was used to compare median differences between scores (95% confidence).

Results

Demographics for 78 (70.3%) participants completing postintervention questionnaires: median age 29.3 (interquartile range: 25.6 to 32.9) years; 54 (69.2%) Crohn’s disease; 21 (26.9%) ulcerative colitis; 63 (80.3%) females, 5 (7.9%) pregnant; and 19 (30.2%) previously pregnant. Postintervention, the median number of reproductive concerns decreased from 3 to 1, and remained stable 6+ months later (P < 0.001*). The median BMQ score decreased from 28 to 25, and remained stable 6+ months later (P = 0.032*). Participants adherent to medications increased from 82.4% to 87.8% postintervention (P = 0.099).

Conclusion

Using an e-health portal may potentially reduce IBD-specific reproductive and medications concerns. An e-health portal is feasible as one component of managing IBD patient’s reproductive and medication concerns during preconception and pregnancy.

The Costs of Industry-Sponsored Medical Device Clinical Trials in Alberta

OBJECTIVE

Our objective was to describe the costs of industry-sponsored clinical trials for medical devices in Northern Alberta, Canada.

METHODS

We used centralized data to identify all industry-sponsored medical device clinical trials initiated in Northern Alberta from 2012 to 2016. For each arm of each trial, we calculated the price of devices provided by the sponsor and the cost of clinical and administrative services that were incurred to clinically operationalize the treatment.

RESULTS

Our sample consisted of 18 device trials initiated between January 2012 and January 2016. The overall cost (Canadian dollars [$Can], year 2018 values) per enrolee was $Can18,243 for the experimental arm and $Can13,827 for the control arm. Devices were the highest cost component, at $Can13,446 per enrollee in the experimental arm. Clinical costs in the control arms were higher on average ($Can7202 vs. 2504) than those in the experimental arms.

CONCLUSION

Data from industry-sponsored clinical trials can provide important information on the full costs of device-related interventions. As device costs rise, and as policy makers require more evidence on device-related treatments, the cost of medical device-driven interventions should be documented along with their effectiveness.

Novel Microbial-Based Immunotherapy Approach for Crohn's Disease

Background: Current Crohn's disease (CD) therapies focus on suppressing immune function and come with consequent risk, such as infection and cancer. Notwithstanding, most CD patients still experience disease progression. There is a need for new CD treatment strategies that offer better health outcomes for patients.

Aims: To assess safety, efficacy, and tolerability of a novel microbial-derived immunotherapy, QBECO, that aims to restore rather than suppress immune function in CD.

Methods: A randomized, double-blind, placebo-controlled trial was conducted in 68 patients with moderate-to-severe CD. Primary endpoints: safety and Week 8 clinical improvement. Secondary endpoints: Week 8 clinical response and remission. Week 8 responders continued blinded treatment through Week 16; non-responders received open-label QBECO from Weeks 9–16. Exploratory analyses included immune biomarker and genotype assessments.

Results: QBECO was well-tolerated. Mean reduction in Crohn's Disease Activity Index (CDAI) score was −68 for QBECO vs. −31 for placebo at Week 8. Improvement with QBECO continued through Week 16 (-130 CDAI reduction). Week 8 QBECO clinical response, improvement and remission rates were 41.2%, 32.4%, 29.4% vs. 26.5%, 23.5%, 23.5% for placebo. TNFα inhibitor-naïve subjects achieved higher response rates at Week 8 with QBECO (64%) vs. placebo (26%). Specific immune biomarkers were identified that linked to QBECO response.

Conclusion: This proof-of-concept study supports further investigation for the use of QBECO as a novel immunotherapy approach for CD. Biomarker analyses suggests it may be feasible to personalize CD treatment with QBECO. Larger trials are now needed to confirm clinical improvement and the unique biological findings.

Clinical Trial Number: NCT01809275 (https://clinicaltrials.gov/ct2/show/NCT01809275)

Early Initiation of Tumor Necrosis Factor Antagonist-Based Therapy for Patients With Crohn's Disease Reduces Costs Compared With Late Initiation

BACKGROUND & AIMS

Antagonists of tumor necrosis factor (TNF) are effective for induction and maintenance of remission of Crohn's disease (CD) and are generally prescribed when patients do not respond to conventional, less-costly medical therapies. Early initiation of anti-TNF therapy reduced rates of surgery and dose escalation due to loss of response. However, these drugs are expensive, so studies are needed on the cost effectiveness of early initiation. We aimed to determine the cost effectiveness of initiating treatment early in the disease course (within 2 years of CD diagnosis) vs later in the disease course (more than 2 years after diagnosis).

METHODS

We constructed a Markov model of a hypothetical cohort of patients with CD in Canada to simulate disease progression after initiation of infliximab or adalimumab therapy. We used published loss-of-response rates to compare the lifetime cost effectiveness of early vs late initiation of anti-TNF therapies. Transition probabilities and utilities were obtained through a literature search, and costs were obtained from the Alberta Ministry of Health. Sensitivity analysis was used to characterize uncertainty.

RESULTS

Early initiation of infliximab yielded an additional 0.72 quality-adjusted life-years (QALYs) and saved $50,418 compared with late initiation. Early initiation of adalimumab yielded an additional 0.54 QALYs and saved $43,969. At a willingness-to-pay threshold of $50,000, early initiations of infliximab or adalimumab therapy had a 74% chance of being cost effective compared with late initiation.

CONCLUSIONS

In a Markov model analysis, we found initiation of either infliximab or adalimumab within 2 years of CD diagnosis to provide significant cost savings and QALYs compared with later initiation (more than 2 years after diagnosis).

IBDoc Canadian User Performance Evaluation

BACKGROUND

Fecal calprotectin (FC) is a stool biomarker that has been shown to be sensitive and specific for mucosal inflammation in patients with inflammatory bowel disease (IBD). The test is limited by the requirement for patients to collect and return stool samples. A home-based FC test may improve test adherence. The aim of this study is to evaluate the usability of the IBDoc, a home-based FC measuring test, and to determine the accuracy of results compared with traditional lab-based ELISA values.

METHODS

Patients were prospectively enrolled from 3 tertiary sites across Canada between May and August 2017. Patients completed a questionnaire establishing ease-of-use of the IBDoc. Patients completed a FC measurement using the IBDoc, and results were compared with an ELISA-determined FC measurement on the same stool sample.

RESULTS

Sixty-one participants were enrolled in the study (29 CD, 32 UC). Seventy-nine percent of patients (48 of 61) agreed that the IBDoc was easy to use, with 85% (52 of 61) of patients strongly agreeing that they were willing use the home kit in the future. The IBDoc and ELISA measurement comparison showed an 88% agreement across all values. There were no false positives or negatives using qualitative comparison.

CONCLUSIONS

The home-based IBDoc FC measuring test is acceptable to patients and correlates extremely well with the standard ELISA-determined FC value. The IBDoc enables clinicians to more easily adopt a treat-to-target approach, improve long-term outcomes, and patients' quality of life with IBD. This study is registered at ClinicalTrials.gov, number NCT03408249.

Association of Genetic Variants in NUDT15 With Thiopurine-Induced Myelosuppression in Patients With Inflammatory Bowel Disease

IMPORTANCE

Use of thiopurines may be limited by myelosuppression. TPMT pharmacogenetic testing identifies only 25% of at-risk patients of European ancestry. Among patients of East Asian ancestry, NUDT15 variants are associated with thiopurine-induced myelosuppression (TIM).

OBJECTIVE

To identify genetic variants associated with TIM among patients of European ancestry with inflammatory bowel disease (IBD).

DESIGN, SETTING, AND PARTICIPANTS

Case-control study of 491 patients affected by TIM and 679 thiopurine-tolerant unaffected patients who were recruited from 89 international sites between March 2012 and November 2015. Genome-wide association studies (GWAS) and exome-wide association studies (EWAS) were conducted in patients of European ancestry. The replication cohort comprised 73 patients affected by TIM and 840 thiopurine-tolerant unaffected patients.

EXPOSURES

Genetic variants associated with TIM.

MAIN OUTCOMES AND MEASURES

Thiopurine-induced myelosuppression, defined as a decline in absolute white blood cell count to 2.5 × 109/L or less or a decline in absolute neutrophil cell count to 1.0 × 109/L or less leading to a dose reduction or drug withdrawal.

RESULTS

Among 1077 patients (398 affected and 679 unaffected; median age at IBD diagnosis, 31.0 years [interquartile range, 21.2 to 44.1 years]; 540 [50%] women; 602 [56%] diagnosed as having Crohn disease), 919 (311 affected and 608 unaffected) were included in the GWAS analysis and 961 (328 affected and 633 unaffected) in the EWAS analysis. The GWAS analysis confirmed association of TPMT (chromosome 6, rs11969064) with TIM (30.5% [95/311] affected vs 16.4% [100/608] unaffected patients; odds ratio [OR], 2.3 [95% CI, 1.7 to 3.1], P = 5.2 × 10-9). The EWAS analysis demonstrated an association with an in-frame deletion in NUDT15 (chromosome 13, rs746071566) and TIM (5.8% [19/328] affected vs 0.2% [1/633] unaffected patients; OR, 38.2 [95% CI, 5.1 to 286.1], P = 1.3 × 10-8), which was replicated in a different cohort (2.7% [2/73] affected vs 0.2% [2/840] unaffected patients; OR, 11.8 [95% CI, 1.6 to 85.0], P = .03). Carriage of any of 3 coding NUDT15 variants was associated with an increased risk (OR, 27.3 [95% CI, 9.3 to 116.7], P = 1.1 × 10-7) of TIM, independent of TPMT genotype and thiopurine dose.

CONCLUSIONS AND RELEVANCE

Among patients of European ancestry with IBD, variants in NUDT15 were associated with increased risk of TIM. These findings suggest that NUDT15 genotyping may be considered prior to initiation of thiopurine therapy; however, further study including additional validation in independent cohorts is required.

Immune Stimulation Using a Gut Microbe-Based Immunotherapy Reduces Disease Pathology and Improves Barrier Function in Ulcerative Colitis

Background: Current ulcerative colitis (UC) treatments are focused on symptom management primarily via immune suppression. Despite the current arsenal of immunosuppressant treatments, the majority of patients with UC still experience disease progression. Importantly, aggressive long-term inhibition of immune function comes with consequent risk, such as serious infections and malignancy. There is thus a recognized need for new, safe and effective treatment strategies for people living with UC that work upstream of managing the symptoms of the disease. The objective of this study was to evaluate a microbial-based treatment, QBECO, that functions to productively activate rather than suppress mucosal immune function as a novel approach to treat UC. Methods: Two established models of experimental colitis, namely chemically-induced DSS colitis and the spontaneous colitis that develops in Muc2 deficient mice, were used to assess whether QBECO treatment could ameliorate gastrointestinal disease. A small exploratory 16-week QBECO open-label trial was subsequently conducted to test the safety and tolerability of this approach and also to determine whether similar improvements in clinical disease and histopathology could be demonstrated in patients with moderate-to-severe UC. Results: QBECO treatment successfully reduced inflammation and promoted mucosal and histological healing in both experimental models and in UC patients. The preclinical models of colitis showed that QBECO ameliorated mucosal pathology, in part by reducing inflammatory cell infiltration, primarily that induced by neutrophils and inflammatory T cells. The most rapid and noticeable change observed in QBECO treated UC patients was a marked reduction in rectal bleeding. Conclusion: Collectively, this work demonstrates for the first time that strategically activating immune function rather than suppressing it, not only does not worsen colitis induced-damage, but may lead to an objective reduction in UC disease pathology.

Preoperative Ustekinumab Treatment Is Not Associated With Increased Postoperative Complications in Crohn's Disease: A Canadian Multi-Centre Observational Cohort Study

BACKGROUND

Ustekinumab (UST), an anti-IL12/23 inhibitor is indicated for moderate-to-severe Crohn's disease (CD). However, it is unclear if patients treated with UST are at increased risk for postoperative complications.

AIM

To evaluate the postoperative safety outcomes in UST-treated CD patients.

METHODS

A multicentre cohort study of UST-treated CD patients at two tertiary care centres (University of Calgary, University of Alberta, Canada) undergoing abdominal surgery between 2009 and 2016 was performed. Postoperative outcomes were compared against a control cohort of anti-TNF-treated patients over the same time-period. The primary outcome was occurrence of postoperative complications up to six months postoperatively, stratified by timing (early <30 days vs. late complications ≥30 days).

RESULTS

Twenty UST-treated patients and 40 anti-TNF-treated patients were included with a median preoperative treatment exposure of 6.5 months and 18 months, respectively (p=0.01). Bowel obstruction was the most common surgical indication in both cohorts. UST-treated patients were more likely to require an ostomy (70.0% vs. 12.5%, p<0.001) and be on combination therapy with either systemic corticosteroids or concurrent immunomodulators (azathioprine or methotrexate) (25.0% vs. 2.5%, p=0.01). Despite the increased concomitant use of immunosuppression in the UST-treated cohort, there were no significant differences in early or late postoperative wound infections (1/20 in UST-cohort, 2/40 in anti-TNF cohort, p=1.00), anastomotic leak (0/20 in UST-cohort, 3/40 in anti-TNF cohort, p=0.54), or postoperative ileus/obstruction (3/20 in UST-cohort, 4/40 in anti-TNF cohort, p=0.67).

CONCLUSIONS

CD patients receiving preoperative UST did not experience an increase in postoperative complications, despite increased use of concurrent immunosuppression.

Heterogeneity in Definitions of Efficacy and Safety Endpoints for Clinical Trials of Crohn's Disease: A Systematic Review

BACKGROUND & AIMS

Endpoints in randomized controlled trials (RCTs) of Crohn's disease (CD) are changing. We performed a systematic review of efficacy and safety outcomes reported in placebo-controlled RCTs of patients with CD.

METHODS

We searched the MEDLINE, EMBASE, and the Cochrane Library through March 1, 2017 for placebo-controlled RCTs of adult patients with CD treated with aminosalicylates, immunomodulators, corticosteroids, biologics, and oral small molecules. Efficacy and safety outcomes, definitions, and measurement tools were collected and stratified by decade of publication.

RESULTS

Our final analysis included 116 RCTs (81 induction, 44 maintenance, 7 postoperative prevention trials, comprising 27,263 patients). Clinical efficacy endpoints were reported in all trials; the most common endpoint was CD activity index score. We identified 38 unique definitions of clinical response or remission and 32 definitions of loss of response. Definitions of endoscopic response, remission, and endoscopic healing were also heterogeneous, evaluated using the CD endoscopic index of severity, the simple endoscopic score for CD, ulcer resolution, and Rutgeerts' Score for postoperative endoscopic appearance. Histologic outcomes were reported in 11.1% of induction trials, 2.3% of maintenance trials, and 14.3% of postoperative prevention trials. Biomarker outcomes were reported in 81.5% induction trials, 68.2% of maintenance trials, and 42.9% of postoperative prevention trials. Safety outcomes were reported in 93.8% of induction trials, 97.7% of maintenance trials, and 85.7% of postoperative prevention trials.

CONCLUSIONS

In this systematic review, we demonstrate heterogeneity in definitions of response and remission, and changes in outcomes reported in RCTs of CD. It is a priority to select a core set of outcomes to standardize efficacy and safety evaluation in trials of patients with CD.

Systematic review with meta-analysis: endoscopic and histologic placebo rates in induction and maintenance trials of ulcerative colitis

BACKGROUND

Regulatory requirements for claims of mucosal healing in ulcerative colitis (UC) will require demonstration of both endoscopic and histologic healing. Quantifying these rates is essential for future drug development.

AIMS

To meta-analyse endoscopic and histologic placebo response and remission rates in UC randomised controlled trials (RCTs) and identify factors influencing these rates.

METHODS

MEDLINE, EMBASE and the Cochrane Library were searched from inception to March 2017 for placebo-controlled trials of pharmacological interventions for UC. Endoscopic and histologic placebo rates were pooled by random effects. Mixed effects univariable and multivariable meta-regression was used to evaluate the influence of patient, intervention and trial-related study-level covariates on these rates.

RESULTS

Fifty-six induction (placebo n = 4171) and 8 maintenance trials (placebo n = 1011) were included. Pooled placebo endoscopic remission and response rates for induction trials were 23% [95 confidence interval (CI) 19-28%] and 35% [95% CI 27-42%] respectively, and 20% [95% CI 16-24%] for maintenance of remission. The pooled histologic placebo remission rate was 14% [95% CI 8-22%] for induction trials. High heterogeneity was observed for all outcomes (I² 56.2%-88.3%). On multivariable meta-regression, central endoscopy reading was associated with significantly lower endoscopic placebo remission rates (16% vs 25%; OR = 0.52, [95% CI 0.29-0.92], P = 0.03). On univariable meta-regression, higher histologic placebo remission was associated with concomitant corticosteroids (OR = 1.17 [95% CI 1.08-1.26], P < 0.0001, per 10% increase in corticosteroid use).

CONCLUSIONS

Placebo endoscopic and histologic rates range from 14% to 35% in UC RCTs but are highly heterogeneous. Outcome standardisation may reduce heterogeneity and is needed in this field.

Heterogeneity in Definitions of Endpoints for Clinical Trials of Ulcerative Colitis: A Systematic Review for Development of a Core Outcome Set

BACKGROUND & AIMS

Advances in development of therapeutic agents for ulcerative colitis (UC) have been paralleled by innovations in trial design. It would be useful to identify a core outcome set, to standardize outcome definitions for efficacy and safety in clinical trials. We performed a systematic review of efficacy and safety outcomes reported in placebo-controlled randomized controlled trials of patients with UC.

METHODS

We searched MEDLINE, EMBASE, and the Cochrane Library from inception through March 1, 2017, for placebo-controlled randomized controlled trials of adult patients with UC treated with aminosalicylates, immunosuppressants, corticosteroids, biologics, and oral small molecules. We collected information on efficacy and safety outcomes, definitions, and measurement tools, stratified by decade of publication.

RESULTS

We analyzed data from 83 randomized controlled trials (68 induction and 15 maintenance) comprising 17,737 patients. Clinical or composite-clinical efficacy outcomes were reported in all trials; the UC Disease Activity Index and Mayo Clinic Score were frequently used to determine clinical response or remission. We found substantial variation in definitions of clinical or composite-clinical endpoints, with more than 50 definitions of response or remission. Endoscopic factors, histologic features, and fecal or serum biomarkers were used to determine outcomes in 83.1% (69 of 83), 24.1% (20 of 83), and 24.1% (20 of 83) of trials, respectively. A greater proportion of trials published after 2007 reported objective outcomes (96.5% endoscopic, 26.3% histologic, and 36.8% biomarker outcomes), but no standardized definitions of histologic or biomarker endpoints were found. Patient-reported efficacy and quality-of-life outcomes were described in 25 trials (30.1%) and safety outcomes were reported in 77 trials (92.8%).

CONCLUSION

In a systematic review, we found that despite recent advances in clinical trials methods, there is a great deal of variation in definitions of endpoints, including response and remission, in randomized controlled trials of patients with UC. Researchers should identify a core set of outcomes to standardize efficacy and safety reporting in UC clinical trials.

A Distinctive Urinary Metabolomic Fingerprint Is Linked With Endoscopic Postoperative Disease Recurrence in Crohn's Disease Patients

BACKGROUND

Crohn's disease (CD) patients who undergo ileocolonic resection frequently have disease recurrence. The aim of this preliminary study was to identify urinary metabolomic profiles associated with disease recurrence in order to identify underlying mechanisms of recurrence and possible disease biomarkers.

METHODS

Biopsies from the neoterminal ileum were collected from CD patients (n = 38) after ileocolonic resection in order to assess mucosa-associated microbiota using 16S rRNA multitag pyrosequencing. Urine samples were collected, and metabolomic profiling was done using high-resolution nuclear magnetic resolution spectroscopy and a combined direct infusion liquid chromatography tandem mass spectrometry. The Rutgeerts scoring system was used to assess endoscopic postoperative recurrence of CD.

RESULTS

There were 28 (73.7%) patients with endoscopic CD recurrence. CD patients who were in endoscopic remission had a higher abundance of Bacteroidetes and lower abundance of Fusobacteria and Proteobacteria in comparison with CD patients who had endoscopic recurrence. In addition, metabolomic profiling could also discriminate between these 2 groups of patients. Endoscopic recurrence was associated with increased concentration of urinary levoglucosan. Rutgeerts score was positively correlated with levoglucosan and propylene glycol levels.

CONCLUSIONS

CD patients who present with endoscopic disease recurrence after surgery have a unique urinary metabolomic fingerprint that can differentiate them from CD patients who are in endoscopic remission after ileocolonic resection. In addition, mucosal-associated microbiota in CD patients with or without disease recurrence after surgery differs and correlates with some urinary metabolites.

Prebiotic Supplementation Following Ileocecal Resection in a Murine Model is Associated With a Loss of Microbial Diversity and Increased Inflammation

BACKGROUND

Individuals with Crohn's disease frequently require ileocecal resection (ICR), and inflammation often recurs in the neoterminal ileum following surgery. Fructooligosaccharide (FOS) is a fermentable prebiotic that stimulates the growth of bifidobacteria and may promote anti-inflammatory activity. The aim of this study was to determine if supplementation of a postICR diet with FOS in a mouse model would be effective in stimulating the growth of bifidobacteria and reducing systemic and local inflammation.

METHODS

ICR was performed in IL10-/- mice (129S1/SvlmJ) with colitis. Following surgery, nonICR control and ICR mice were fed a chow diet ± 10% FOS for 28 days. Serum, colon, and terminal ileum (TI) were analyzed for cytokine expression by MesoScale discovery platform. DNA extracted from stool was analyzed using 16s rRNA sequencing and qPCR. Expression of occludin and ZO1 was assessed using qPCR. Short-chain fatty acid (SCFA) concentrations were assessed using gas chromatography.

RESULTS

ICR led to increased systemic inflammation (P < 0.05) and a significant decline in fecal microbial diversity (P < 0.05). Mice on the FOS diet had a greater reduction in microbial diversity and also had worsened inflammation as evidenced by increased serum IL-6 (P < 0.05) and colonic IFNγ and TNFα (P < 0.05). Expression of occludin and ZO1 were significantly reduced in FOS-supplemented mice. There was a correlation between loss of diversity and the bifidogenic effectiveness of FOS (r = -0.61, P < 0.05).

CONCLUSIONS

FOS-supplementation of a postICR diet resulted in a decrease in fecal bacterial diversity, reduction in barrier function, and increased gut inflammation.

Ileocolic resection is associated with increased susceptibility to injury in a murine model of colitis

Ileocolic resection (ICR) is the most common intestinal resection performed for Crohn's disease, with recurrences commonly occurring at the site of the anastomosis. This study used an animal model of ICR in wild-type mice to examine immunologic changes that developed around the surgical anastomosis and how these changes impacted gut responses to minor acute injury. ICR was performed in adult 129S1/SvlmJ mice and results compared with mice receiving sham or no surgery. Dextran sodium sulfate was given either on post-operative day 9 or day 24 to evaluate immune responses in the intestine both immediately following surgery and after a period of healing. Fecal occult blood measurements and animal weights were taken daily. Cytokine levels were measured in ileal and colonic tissue. Bacterial load in the neo-terminal ileum was measured using qPCR. Immune cell populations in the intestinal tissue, mesenteric lymph nodes, and spleen were assessed using flow cytometry. Cytokine secretion in response to microbial products was measured in isolated mesenteric lymph nodes and spleen cells. ICR resulted in an initial elevation of inflammatory markers in the terminal ileum and colon followed by enhanced levels of bacterial growth in the neo-terminal ileum. Intestinal surgical resection resulted in the recruitment of innate immune cells into the colon that exhibited a non-responsiveness to microbial stimuli. DSS colitis phenotype was more severe in the ileocolic resection groups and this was associated with local and systemic immunosuppression as evidenced by a reduced cytokine responses to microbial stimuli. This study reveals the development of an immune non-responsiveness to microbial products following ileocolic resection that is associated with enhanced levels of bacterial growth in the neo-terminal ileum. These surgical-induced altered immune-microbial interactions in the intestine may contribute to disease recurrence at the surgical anastomosis site following ileocolic resections in patients with Crohn's disease.

Development of a core outcome set for clinical trials in inflammatory bowel disease: study protocol for a systematic review of the literature and identification of a core outcome set using a Delphi survey

INTRODUCTION

Crohn's disease (CD) and ulcerative colitis (UC), the main forms of inflammatory bowel disease (IBD), are chronic, progressive and disabling disorders of the gastrointestinal tract. Although data from randomised controlled trials (RCTs) provide the foundation of evidence that validates medical therapy for IBD, considerable heterogeneity exists in the measured outcomes used in these studies. Furthermore, in recent years, there has been a paradigm shift in IBD treatment targets, moving from symptom-based scoring to improvement or normalisation of objective measures of inflammation such as endoscopic appearance, inflammatory biomarkers and histological and radiographic end points. The abundance of new treatment options and evolving end points poses opportunities and challenges for all stakeholders involved in drug development. Accordingly, there exists a need to harmonise measures used in clinical trials through the development of a core outcome set (COS).

METHODS AND ANALYSIS

The development of an IBD-specific COS includes four steps. First, a systematic literature review is performed to identify outcomes previously used in IBD RCTs. Second, semistructured qualitative interviews are conducted with key stakeholders, including patients, clinicians, researchers, pharmaceutical industry representatives, healthcare payers and regulators to identify additional outcomes of importance. Using the outcomes generated from literature review and stakeholder interviews, an international two-round Delphi survey is conducted to prioritise outcomes for inclusion in the COS. Finally, a consensus meeting is held to ratify the COS and disseminate findings for application in future IBD trials.

ETHICS AND DISSEMINATION

Given that over 30 novel therapeutic compounds are in development for IBD treatment, the design of robust clinical trials measuring relevant and standardised outcomes is crucial. Standardising outcomes through a COS will reduce heterogeneity in trial reporting, facilitate valid comparisons of new therapies and improve clinical trial quality.

Dietary and metabolomic determinants of relapse in ulcerative colitis patients: A pilot prospective cohort study

AIM

To identify demographic, clinical, metabolomic, and lifestyle related predictors of relapse in adult ulcerative colitis (UC) patients.

METHODS

In this prospective pilot study, UC patients in clinical remission were recruited and followed-up at 12 mo to assess a clinical relapse, or not. At baseline information on demographic and clinical parameters was collected. Serum and urine samples were collected for analysis of metabolomic assays using a combined direct infusion/liquid chromatography tandem mass spectrometry and nuclear magnetic resolution spectroscopy. Stool samples were also collected to measure fecal calprotectin (FCP). Dietary assessment was performed using a validated self-administered food frequency questionnaire.

RESULTS

Twenty patients were included (mean age: 42.7 ± 14.8 years, females: 55%). Seven patients (35%) experienced a clinical relapse during the follow-up period. While 6 patients (66.7%) with normal body weight developed a clinical relapse, 1 UC patient (9.1%) who was overweight/obese relapsed during the follow-up (P = 0.02). At baseline, poultry intake was significantly higher in patients who were still in remission during follow-up (0.9 oz vs 0.2 oz, P = 0.002). Five patients (71.4%) with FCP > 150 μg/g and 2 patients (15.4%) with normal FCP (≤ 150 μg/g) at baseline relapsed during the follow-up (P = 0.02). Interestingly, baseline urinary and serum metabolomic profiling of UC patients with or without clinical relapse within 12 mo showed a significant difference. The most important metabolites that were responsible for this discrimination were trans-aconitate, cystine and acetamide in urine, and 3-hydroxybutyrate, acetoacetate and acetone in serum.

CONCLUSION

A combination of baseline dietary intake, fecal calprotectin, and metabolomic factors are associated with risk of UC clinical relapse within 12 mo.

Clinical, endoscopic and radiographic outcomes with ustekinumab in medically-refractory Crohn's disease: real world experience from a multicentre cohort

BACKGROUND

Ustekinumab is a monoclonal antibody targeting interleukins-12 and -23, with efficacy in Crohn's disease (CD) demonstrated in clinical trials.

AIM

To assess the real-world clinical, endoscopic and radiographic response and remission outcomes achieved with ustekinumab in medically-refractory CD.

METHODS

A retrospective multicentre cohort study was performed on CD patients receiving ustekinumab between 2011 and 2016. The primary outcome was achievement of clinical and objective steroid-free response and remission at 3, 6 and 12 months. Clinical response and remission were defined by reduction in Harvey Bradshaw Index (HBI) of ≥3 points and an HBI ≤4 points respectively. Objective response was defined by improvement in endoscopic or radiographic CD, as assessed by ileocolonoscopy, contrast-enhanced ultrasound or CT/MR enterography. Objective remission was defined by endoscopic mucosal healing or complete resolution of inflammatory parameters on radiographic assessment.

RESULTS

A total of 167 CD patients were treated with ustekinumab. 95.2% (159/167) previously failed anti-TNF therapy. Median follow-up was 45.6 weeks (IQR: 24.4-88.9). At 3 months, clinical response was achieved in 38.9% (65/167) and remission in 15.0% (25/167) of patients. At 6 months, clinical response was achieved in 60.3% (91/151) and remission in 25.2% (38/151) of patients. At 12 months, clinical response was achieved in 59.5% (66/111) and remission in 27.9% (31/111) of patients. Endoscopic or radiographic response was demonstrated in 54.5% (67/123) at 6 months and 55.8% (48/86) of patients at 12 months.

CONCLUSIONS

Ustekinumab is an effective therapeutic option for inducing and maintaining clinical, endoscopic and radiographic response in patients with Crohn's disease failing anti-TNF therapy.

Clinical validation of a novel urine-based metabolomic test for the detection of colonic polyps on Chinese population

PURPOSE

Colorectal cancer is the fifth leading cause of cancer-related deaths in China. When detected early, with the removal of adenomatous polyps, precursors of colorectal cancer, it is preventable. The aim of this study was to evaluate a novel urine-based metabolomic diagnostic test for the detection of adenomatous polyps, PolypDx™, that was originally developed and validated using 1000 samples from Canadian Cohort, on Chinese population.

METHODS

Prospective urine samples were collected from 1000 participants undergoing colonoscopy examination, from March 2013 to July 2014 at Minhang District, Shanghai Centre for Disease Control and Prevention. One-dimensional nuclear magnetic resonance spectra of urine metabolites were analyzed to determine the concentrations of three key metabolites used in PolypDx™. The predicted results were then compared to the gold standard for colorectal cancer diagnostic, colonoscopy. Area under curve (AUC) was calculated specifically for the Chinese population and compared with the Canadian dataset. Sensitivity and specificity of this urine-based metabolomic diagnostic test were also compared with three commercially available fecal-based tests.

RESULTS

An AUC of 0.717 for PolypDx™ was calculated on Chinese dataset which is slightly lower than the AUC on the Canadian dataset. A sensitivity of 82.6% and a specificity of 42.4% were achieved on Chinese dataset.

CONCLUSIONS

Here, we validated a novel urine-based metabolomic diagnostic test for the detection of adenomatous polyps, PolypDx™, on Chinese population through a sample size of 1000 participants with a greater level of sensitivity than fecal-based tests.

Primary Outcomes From a Phase 3, Randomized, Double-Blind, Active-Controlled Trial of Surotomycin in Subjects With Clostridium difficile Infection

Background

Although the incidence of Clostridium difficile infection (CDI) is increasing, available CDI treatment options are limited in terms of sustained response after treatment. This phase 3 trial assessed the efficacy and safety of surotomycin, a novel bactericidal cyclic lipopeptide, versus oral vancomycin in subjects with CDI.

Methods

In this randomized, double-blind, active-controlled, multicenter, international trial, subjects with CDI confirmed by a positive toxin result were randomized to receive surotomycin (250 mg twice daily) or vancomycin (125 mg 4 times daily) orally for 10 days. The primary endpoints were clinical response at end of treatment and evaluation of surotomycin safety. The key secondary endpoints were clinical response over time and sustained clinical response through a 30- to 40-day follow-up period. Clostridium difficile infection recurrence during follow-up and time to diarrhea resolution were also analyzed.

Results

In total, 570 subjects were randomized and had confirmed CDI; 290 subjects received surotomycin and 280 subjects received vancomycin. Surotomycin clinical cure rates at end of treatment (surotomycin/vancomycin: 79.0%/83.6%; difference of −4.6%; 95% confidence interval, −11.0 to 1.9]), clinical response over time (stratified log-rank test, P = .832), and sustained clinical response at end of trial (Day 40–50) (60.6%/61.4%; difference of −0.8%; 95% CI, −8.8 to 7.1) in the microbiological modified intent to treat population did not meet noninferiority or superiority criteria versus vancomycin. Both treatments were generally well tolerated.

Conclusions

Surotomycin failed to meet the criteria for noninferiority versus vancomycin for the primary and key secondary endpoints in this trial.

Epithelial Cell Extrusion Zones Observed on Confocal Laser Endomicroscopy Correlates with Immunohistochemical Staining of Mucosal Biopsy Samples

BACKGROUND AND AIMS

The density of epithelial cell extrusion zones in the intestinal lining, also known as gap density (number of gaps/1000 epithelial cells counted), can be quantitated using probe-based confocal laser endomicroscopy (pCLE). Gap density has been reported to be higher than normal in both inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) patients. Epithelial cells destined for extrusion from the intestinal surface would stain positive for either activated caspase-1 or caspase-3 on mucosal biopsy samples. The aim of this study was to determine whether epithelial gap density on pCLE correlates with quantitative analysis of activated caspase staining of mucosal biopsy samples from patients.

METHODS

We obtained pCLE images and biopsy samples of the terminal ileum during colonoscopies of healthy controls and patients with either IBD or IBS. The pCLE images and biopsy samples were blindly analyzed for gap density and for cells staining positive for activated caspases, respectively. The degree of correlation was determined using nonparametric statistical tests.

RESULTS

The median results were 10 gaps/1000 cells counted for controls versus 33 gaps/1000 cells counted for chronic intestinal disorder patients (p = 0.02). Activated caspase staining showed 13 positive cells/1000 epithelial cells counted versus 26 positive cells/1000 epithelial cells counted, respectively (p = 0.02), thus showing a strong correlation with a Spearman's coefficient ρ of 0.61 (strong correlation for ρ = 0.4-0.75, p = 0.01).

CONCLUSIONS

Intestinal epithelial gap density via pCLE correlated strongly with quantitative analysis of immunohistochemical staining of mucosal biopsy samples.

Practical Considerations and the Intestinal Microbiome in Disease: Antibiotics for IBD Therapy

The inflammatory bowel diseases, Crohn's and ulcerative colitis, have been treated with a range of antibiotics for inducing and maintaining remission, as well as the prevention of post-operative symptoms. To date, many studies have been performed assessing the efficacy of antibiotics when used alone, in combination with other antibiotics, or as an adjunctive therapy to other pharmaceutical treatments. Literature evidence supporting the use of antibiotics in IBD can be ambiguous, especially when considering the potential role of dysbiosis in the gastrointestinal tract. The review considers the systemic effect of antibiotics and the evidence base for their efficacy in the treatment of IBD.

Lymphoproliferative disorders in inflammatory bowel disease patients on immunosuppression: Lessons from other inflammatory disorders

Immunosuppressive agents, such as thiopurines, methotrexate, and biologics, have revolutionized the treatment of inflammatory bowel disease (IBD). However, a number of case reports, case control studies and retrospective studies over the last decade have identified a concerning link between immunosuppression and lymphoproliferative disorders (LPDs), the oncological phenomenon whereby lymphocytes divide uncontrollably. These LPDs have been associated with Epstein-Barr virus (EBV) infection in which the virus provides the impetus for malignant transformation while immunosuppression hampers the immune system’s ability to detect and clear these malignant cells. As such, the use of immunosuppressive agents may come at the cost of increased risk of developing LPD. While little is known about the LPD risk in IBD, more is known about immunosuppression in the post-transplantation setting and the development of EBV associated post-transplantation lymphoproliferative disorders (PTLD). In review of the PTLD literature, evidence is available to demonstrate that certain immune suppressants such as cyclosporine and T-lymphocyte modulators in particular are associated with an increased risk of PTLD development. As well, high doses of immunosuppressive agents and multiple immunosuppressive agent use are also linked to increased PTLD development. Here, we discuss these findings in context of IBD and what future studies can be taken to understand and reduce the risk of EBV-associated LPD development from immunosuppression use in IBD.

Randomised clinical trial: vercirnon, an oral CCR9 antagonist, vs. placebo as induction therapy in active Crohn's disease

BACKGROUND

Many patients with active Crohn's disease do not adequately respond to therapies, highlighting the need for new treatments.

AIMS

To conduct a randomised, double-blind, placebo-controlled phase 3 study to assess the efficacy and safety of vercirnon, an oral inhibitor of CC chemokine receptor-9, for the treatment of patients with moderately-to-severely active Crohn's disease.

METHODS

Patients with a Crohn's Disease Activity Index (CDAI) of 220-450, plus evidence of active disease (endoscopically confirmed or elevation of both C-reactive protein and faecal calprotectin), who had failed corticosteroid or immunosuppressant therapy were enrolled. Patients were equally randomised to receive placebo, vercirnon 500 mg once daily or vercirnon 500 mg twice daily. The primary endpoint was clinical response, defined as a 100-point decrease in CDAI from baseline to week 12.

RESULTS

Six hundred and eight patients were randomised. Patient characteristics and baseline demographics were similar among the groups. The proportions of patients achieving a clinical response were 25.1%, 27.6% and 27.2% for placebo, once daily and twice daily respectively; treatment differences were not significant (2.5%; 95% confidence interval, CI -6.1% to 11.0%, P = 0.546 for once daily vs. placebo, and 2.1%; 95% CI -6.5% to 10.7%, P = 0.648 for twice daily vs. placebo). Adverse events were reported in 69.8%, 73.3% and 78.1% with serious adverse events in 8.9%, 5.9%, and 6.0% of patients in the placebo, once-daily and twice-daily groups, respectively.

CONCLUSIONS

We did not demonstrate efficacy of vercirnon as an induction therapy in patients with moderately-to-severely active Crohn's disease; its effect in maintenance therapy was not addressed.

TP53 codon 72 Arg/Arg polymorphism is associated with a higher risk for inflammatory bowel disease development

AIM: To investigate the association between tumor protein 53 (TP53) codon 72 polymorphisms and the risk for inflammatory bowel disease (IBD) development.

METHODS: Numerous genetic and epigenetic drivers have been identified for IBD including the TP53 gene. Pathogenic mutations in TP53 gene have only been reported in 50% of colorectal cancer (CRC) patients. A single nucleotide polymorphism (SNP) in the TP53 gene resulting in the presence of either arginine (Arg) or proline (Pro) or both at codon 72 was shown to alter TP53 tumor-suppressor properties. This SNP has been investigated as a risk factor for numerous cancers, including CRC. In this study we analyzed TP53 codon 72 polymorphism distribution in 461 IBD, 181 primary sclerosing cholangitis patients and 62 healthy controls. Genotyping of TP53 was performed by sequencing and restriction fragment length polymorphism analysis of genomic DNA extracted from peripheral blood.

RESULTS: The most frequent TP53 genotype in IBD patients was Arg/Arg occurring in 54%-64% of cases (and in only 32% of controls). Arg/Pro was the most prevalent genotype in controls (53%) and less common in patients (31%-40%). Pro/Pro frequency was not significantly different between controls and IBD patients.

CONCLUSION: The data suggests that the TP53 codon 72 Arg/Arg genotype is associated with increased risk for IBD development.

Larazotide acetate for persistent symptoms of celiac disease despite a gluten-free diet: a randomized controlled trial

BACKGROUND & AIMS

Celiac disease (CeD) is a prevalent autoimmune condition. Recurrent signs and symptoms are common despite treatment with a gluten-free diet (GFD), yet no approved or proven nondietary treatment is available.

METHODS

In this multicenter, randomized, double-blind, placebo-controlled study, we assessed larazotide acetate 0.5, 1, or 2 mg 3 times daily to relieve ongoing symptoms in 342 adults with CeD who had been on a GFD for 12 months or longer and maintained their current GFD during the study. The study included a 4-week placebo run-in, 12 weeks of treatment, and a 4-week placebo run-out phase. The primary end point was the difference in average on-treatment Celiac Disease Gastrointestinal Symptom Rating Scale score.

RESULTS

The primary end point was met with the 0.5-mg dose of larazotide acetate, with fewer symptoms compared with placebo by modified intention to treat (n = 340) (analysis of covariance, P = .022; mixed model for repeated measures, P = .005). The 0.5-mg dose showed an effect on exploratory end points including a 26% decrease in celiac disease patient-reported outcome symptomatic days (P = .017), a 31% increase in improved symptom days (P = .034), a 50% or more reduction from baseline of the weekly average abdominal pain score for 6 or more of 12 weeks of treatment (P = .022), and a decrease in the nongastrointestinal symptoms of headache and tiredness (P = .010). The 1- and 2-mg doses were no different than placebo for any end point. Safety was comparable with placebo.

CONCLUSIONS

Larazotide acetate 0.5 mg reduced signs and symptoms in CeD patients on a GFD better than a GFD alone. Although results were mixed, this study was a successful trial of a novel therapeutic agent targeting tight junction regulation in patients with CeD who are symptomatic despite a GFD. Clinicaltrials.gov: NCT01396213.

The probiotic VSL#3 has anti-inflammatory effects and could reduce endoscopic recurrence after surgery for Crohn's disease

BACKGROUND & AIMS

Probiotic formulations of single species of bacteria have not been effective in preventing the recurrence of Crohn's disease after surgery. We investigated the ability of VSL#3, a mixture of 8 different bacterial probiotic species, to prevent Crohn's disease recurrence after surgery in a multicenter, randomized, double-blind, placebo-controlled trial.

METHODS

Within 30 days of ileocolonic resection and re-anastomosis, patients with Crohn's disease were randomly assigned to groups given 1 sachet of VSL#3 (900 billion viable bacteria, comprising 4 strains of Lactobacillus, 3 strains of Bifidobacterium, and 1 strain of Streptococcus salivarius subspecies thermophilus) (n = 59) or matching placebo (n = 60). Colonoscopy was performed at days 90 and 365 to evaluate the neoterminal ileum for disease recurrence and obtain mucosal biopsies for cytokine analysis. Patients from both groups with either no or mild endoscopic recurrence at day 90 received VSL#3 until day 365. The primary outcome was the proportion of patients with severe endoscopic recurrence at day 90.

RESULTS

At day 90, the proportion of patients with severe endoscopic lesions did not differ significantly between VSL#3 (9.3%) and placebo (15.7%, P = .19). The proportions of patients with non-severe lesions at day 90 who had severe endoscopic recurrence at day 365 were 10.0% in the early VSL#3 group (given VSL#3 for the entire 365 days) and 26.7% in the late VSL#3 group (given VSL#3 from days 90 through 365) (P = .09). Aggregate rates of severe recurrence (on days 90 and 365) were not statistically different, 20.5% of subjects in the early VSL#3 group and 42.1% in the late VSL#3 group. Patients receiving VSL#3 had reduced mucosal inflammatory cytokine levels compared with placebo at day 90 (P < .05). Crohn's disease activity index and inflammatory bowel disease quality of life scores were similar in the 2 groups.

CONCLUSIONS

There were no statistical differences in endoscopic recurrence rates at day 90 between patients who received VSL#3 and patients who received placebo. Lower mucosal levels of inflammatory cytokines and a lower rate of recurrence among patients who received early VSL#3 (for the entire 365 days) indicate that this probiotic should be further investigated for prevention of Crohn's disease recurrence. Clinical trials.gov number: NCT00175292.

Adalimumab dose escalation is effective for managing secondary loss of response in Crohn's disease

BACKGROUND

The efficacy of adalimumab in maintaining remission in Crohn's disease patients may wane over time, leading to secondary loss of response that is often managed with dose escalation. However, the response to adalimumab dose escalation and long-term outcomes after escalation have not been well evaluated.

AIMS

To characterise the short- and long-term clinical responses to adalimumab dose escalation for secondary loss of response.

METHODS

A retrospective cohort study evaluating Crohn's disease out-patients requiring adalimumab dose escalation for secondary loss of response from 2003 to 2013 was conducted. The primary outcome was the proportion of patients achieving symptomatic clinical response to dose escalation and subsequent development of tertiary loss of response. Duration of regained response was assessed by Kaplan-Meier analysis.

RESULTS

Ninety-two CD patients met inclusion criteria with mean duration of follow-up of 170.2 weeks (±129.6 weeks). Disease distribution was predominantly ileal (37/92, 40.2%) or ileocolonic (43/92, 46.7%), with equal distribution of inflammatory (34.8%), stricturing (27.2%), and penetrating (38.0%) disease phenotypes. At 24 weeks post-dose escalation, 74/92 (80.4%) patients had symptomatic clinical response. Among responders, median duration of sustained response was 69.2 weeks (IQR 29.4-107.1) but 42/74 (56.8%) responders experienced subsequent tertiary loss of response at a median time of 47.9 weeks (IQR 24.7-80.3). C-reactive protein >10.0 mg/L at the time of dose escalation predicted tertiary loss of response in univariate analysis (OR 3.32, 95% CI: 1.18-9.37).

CONCLUSIONS

In patients with Crohn's disease, adalimumab dose escalation is effective for recapturing symptomatic response after secondary loss of response, but more than half will eventually experience a tertiary loss of response.

Real-life treatment paradigms show infliximab is cost-effective for management of ulcerative colitis

BACKGROUND & AIMS

Infliximab is effective for induction and maintenance of response in patients with moderate to moderately severe ulcerative colitis. Previous cost analyses of infliximab treatment for ulcerative colitis used models of colectomy vs infliximab and response rates derived from early clinical trials. In real life, therapeutic options are more complex; patients frequently choose to remain in an unwell state rather than undergo colectomy, and rates of response to infliximab are generally higher than those reported from clinical trials. We evaluate the real-life cost-effectiveness of infliximab for treatment of ulcerative colitis where infliximab was readily available compared with not available, causing patients to remain in unwell states.

METHODS

We constructed a Markov model to simulate disease progression of patients with moderate or moderately severe ulcerative colitis who depended on corticosteroids and/or did not respond to thiopurine therapy. Utility scores and transition probabilities between health states were determined by using data from randomized controlled trials and real-life rates published by expert inflammatory bowel disease centers. Health care costs were obtained from the Ontario Case Costing Initiative and the Alberta Health Schedule of Medical Benefits documents.

RESULTS

The incremental cost-effectiveness ratios for infliximab treatment of ulcerative colitis were $79,000 and $64,000 per quality-adjusted life year, compared with ongoing medical therapy, at 5-year and 10-year treatment time horizons, respectively.

CONCLUSIONS

By using real-life response rates and patients' preference to avoid colectomy, infliximab therapy is a cost-effective strategy at a willingness-to-pay threshold of $80,000 for treatment of ulcerative colitis.

Crohn's disease outpatients treated with adalimumab have an earlier secondary loss of response and requirement for dose escalation compared to infliximab: a real life cohort study

BACKGROUND

The efficacy of anti-tumor necrosis factor alpha agents in maintaining remission in Crohn's disease may wane over time, leading to secondary loss of response that can often be overcome with dose escalation. Comparison of secondary loss of response of adalimumab and infliximab during long-term treatment of CD in a real-life IBD clinic has not been previously evaluated.

METHODS

A retrospective cohort study was conducted evaluating outpatients with CD on a maintenance regimen with adalimumab or infliximab from 200 to 2013 and who experienced a secondary loss of response. All infliximab-treated patients were anti-TNF naïve. Adalimumab-treated patients were stratified by prior anti-TNF exposure. Kaplan-Meier analysis was conducted to compare time to loss of response.

RESULTS

218 CD patients met inclusion criteria (117 infliximab, 101 adalimumab). Median follow-up duration was 170.0weeks for infliximab and 122.0weeks for adalimumab (p=0.61). The proportion of patients with secondary loss of response was similar for infliximab-treated - 51.3% (60/117) compared to adalimumab patients naïve to anti-TNF therapy - 60.5% (23/38) (p=0.32), and adalimumab patients with prior anti-TNF exposure - 65.1% (41/63) (p=0.08). Median time to secondary loss of response was longer for infliximab patients (99.3wk, IQR 55.7-168.5) compared to both adalimumab patients naïve to anti-TNF therapy (58.9wk, IQR 29.0-85.7) (p=0.03), and adalimumab patients with prior anti-TNF exposure (52.7wk, IQR 20.1-85.0) (p<0.001).

CONCLUSIONS

Over 50% of CD patients treated with infliximab and adalimumab develop secondary loss of response. Time to loss of response was shorter in patients treated with adalimumab compared to those treated with infliximab. Prior anti-TNF exposure further accelerated time to loss of response.

HLA-DQA1-HLA-DRB1 variants confer susceptibility to pancreatitis induced by thiopurine immunosuppressants

Pancreatitis occurs in approximately 4% of patients treated with the thiopurines azathioprine or mercaptopurine. Its development is unpredictable and almost always leads to drug withdrawal. We identified patients with inflammatory bowel disease (IBD) who had developed pancreatitis within 3 months of starting these drugs from 168 sites around the world. After detailed case adjudication, we performed a genome-wide association study on 172 cases and 2,035 controls with IBD. We identified strong evidence of association within the class II HLA region, with the most significant association identified at rs2647087 (odds ratio 2.59, 95% confidence interval 2.07-3.26, P = 2 × 10(-16)). We replicated these findings in an independent set of 78 cases and 472 controls with IBD matched for drug exposure. Fine mapping of the HLA region identified association with the HLA-DQA1*02:01-HLA-DRB1*07:01 haplotype. Patients heterozygous at rs2647087 have a 9% risk of developing pancreatitis after administration of a thiopurine, whereas homozygotes have a 17% risk.

The incidence rate of colectomy for medically refractory ulcerative colitis has declined in parallel with increasing anti-TNF use: a time-trend study

BACKGROUND

Medical therapy is standard treatment for ulcerative colitis with colectomy reserved for medically refractory disease or malignancy. The introductions of ciclosporin in 1994 and anti-TNF therapy in 2005 have extended medical management options.

AIM

To determine whether the colectomy incidence rate for medically refractory ulcerative colitis has changed since the introduction of anti-TNF therapy.

METHODS

Adult patients with a diagnosis of ulcerative colitis and who subsequently underwent an urgent or elective colectomy for medically refractory disease in Edmonton, Canada between 1 January 1998 and 31 December 2011 were identified. Log-linear regression was used to estimate the annual percent change in the total colectomy incidence rate (urgent and elective combined) and the urgent and elective incidence rates individually, before and after 2005, the year infliximab was approved for use in ulcerative colitis. Temporal trends of drug utilisation in this study population were also described.

RESULTS

During 1998-2011, 481 patients with ulcerative colitis underwent a colectomy for medically refractory disease. There was negligible change in the total colectomy incidence rate from 1998 to 2005, with an annual percent change of 4.4% (95% confidence interval (CI): -1.12% to 10.16%). From 2005-2011, following the approval and increasing use of anti-TNF therapy, the total colectomy incidence rate decreased by 16.1% (95% CI: -21.32% to -10.54%) every year to 0.9 per 100 ulcerative colitis patients in 2011.

CONCLUSION

The total incidence rate of colectomy for medically refractory ulcerative colitis has declined substantially since 2005, paralleling the increased use of anti-TNF therapy in this patient population.

Adalimumab versus infliximab for the treatment of moderate to severe ulcerative colitis in adult patients naïve to anti-TNF therapy: an indirect treatment comparison meta-analysis

OBJECTIVE

To compare the efficacy of adalimumab and infliximab for the treatment of moderate to severe ulcerative colitis using indirect treatment comparison meta-analysis.

METHODS

A systematic review and Bayesian indirect treatment comparison meta-analyses were performed for seven patient-important clinical outcomes at 8 weeks and 52 weeks. Odds ratio (OR) estimates and associated 95% credible intervals (CrIs) were produced.

RESULTS

Five eligible RCTs informed clinical remission, response, mucosal healing, quality of life, colectomy, serious adverse events, and discontinuation due to adverse events at 8 weeks and 52 weeks. At 8 weeks of induction therapy, clinical remission (OR=0.42, 95% CrI 0.17-0.97), clinical response (OR=0.45, 95% CrI 0.23-0.89) and mucosal healing (OR=0.46, 95% CrI 0.25-0.86) statistically favored infliximab. However, after 52 weeks of maintenance therapy OR estimates showed no significant difference between infliximab and adalimumab. For serious adverse events and discontinuations due to adverse events, adalimumab and infliximab were similar to placebo. Further, the indirect treatment comparison of adalimumab and infliximab yielded odds ratios close to 1.00 with wide credible intervals.

CONCLUSION

The findings of this indirect treatment comparison meta-analysis suggest that both infliximab and adalimumab are superior to placebo in the treatment of moderate to moderately severe ulcerative colitis. While infliximab is statistically more effective than adalimumab in the induction of remission, response and mucosal healing at 8 weeks, infliximab and adalimumab are comparable in efficacy at 52 weeks of maintenance treatment.

Vitamin D improves inflammatory bowel disease outcomes: Basic science and clinical review

Vitamin D deficiency is commonly diagnosed among patients with inflammatory bowel disease (IBD). Patients with IBD are at risk of low bone density and increased fractures due to low vitamin D levels, long standing disease, and frequent steroid exposures; as a result, it is well established that vitamin D supplementation in this population is important. There is increasing support for the role of vitamin D in strengthening the innate immune system by acting as an immunomodulator and reducing inflammation in experimental and human IBD. The active form of vitamin D, 1,25(OH)D3, acts on T cells to promote T helper (Th)2/regulatory T responses over Th1/Th17 responses; suppresses dendritic cell inflammatory activity; induces antibacterial activity; and regulates cytokine production in favor of an anti-inflammatory response. Murine and human IBD studies support a therapeutic role of vitamin D in IBD. Risk factors for vitamin D deficiency in this population include decreased sunlight exposure, disease duration, smoking, and genetics. Vitamin D normalization is associated with reduced risk of relapse, reduced risk of IBD-related surgeries, and improvement in quality of life. Vitamin D is an inexpensive supplement which has been shown to improve IBD outcomes. However, further research is required to determine optimal serum vitamin D levels which will achieve beneficial immune effects, and stronger evidence is needed to support the role of vitamin D in inducing disease response and remission, as well as maintaining this improvement in patients’ disease states.

Development and validation of a highly sensitive urine-based test to identify patients with colonic adenomatous polyps

Objectives:

Adenomatous polyps are precursors of colorectal cancer; their detection and removal is the goal of colon cancer screening programs. However, fecal-based methods identify patients with adenomatous polyps with low levels of sensitivity. The aim or this study was to develop a highly accurate, prototypic, proof-of-concept, spot urine-based diagnostic test using metabolomic technology to distinguish persons with adenomatous polyps from those without polyps.

Methods:

Prospective urine and stool samples were collected from 876 participants undergoing colonoscopy examination in a colon cancer screening program, from April 2008 to October 2009 at the University of Alberta. Colonoscopy reference standard identified 633 participants with no colonic polyps and 243 with colonic adenomatous polyps. One-dimensional nuclear magnetic resonance spectra of urine metabolites were analyzed to define a diagnostic metabolomic profile for colonic adenomas. A urine metabolomic diagnostic test for colonic adenomatous polyps was established using 67% of the samples (un-blinded training set) and validated using the other 33% of the samples (blinded testing set). The urine metabolomic diagnostic test's specificity and sensitivity were compared with those of fecal-based tests.

Results:

Using a two-component, orthogonal, partial least-squares model of the metabolomic profile, the un-blinded training set identified patients with colonic adenomatous polyps with 88.9% sensitivity and 50.2% specificity. Validation using the blinded testing set confirmed sensitivity and specificity values of 82.7% and 51.2%, respectively. Sensitivities of fecal-based tests to identify colonic adenomas ranged from 2.5 to 11.9%.

Conclusions:

We describe a proof-of-concept spot urine-based metabolomic diagnostic test that identifies patients with colonic adenomatous polyps with a greater level of sensitivity (83%) than fecal-based tests.

Phenotypic features of Crohn's disease associated with failure of medical treatment

BACKGROUND & AIMS

There is conflicting evidence on the effects of thiopurines (azathioprine or mercaptopurine) and anti-tumor necrosis factor (TNF) therapies on rates of surgery among patients with Crohn's disease (CD). We aimed to identify factors that identify patients who are unlikely to respond to medical therapy and will therefore require surgery.

METHODS

We performed a retrospective study using the Alberta Inflammatory Bowel Disease Consortium registry to identify 425 patients diagnosed with CD who received a prescription of a thiopurine and/or an anti-TNF agent from a referral center, from July 1, 1975, through September 13, 2012. We collected data on CD-related abdominal surgery after therapy and disease features when therapy was instituted. Cox proportional regression models were used to associate disease features with outcomes after adjusting for potential confounders. Risk estimates were presented as hazard rate ratios (HRRs) with 95% confidence intervals (CIs).

RESULTS

Among patients given thiopurines, stricturing disease (adjusted HR, 4.63; 95% CI, 2.00-10.71), ileal location (adjusted HR, 6.20; 95% CI, 1.64-23.42), and ileocolonic location (adjusted HR, 3.71; 95% CI, 1.08-12.74) at the time of prescription were associated significantly with the need for surgery. Prescription of an anti-TNF agent after prescription of a thiopurine reduced the risk for surgery, compared with patients prescribed only a thiopurine (adjusted HR, 0.41; 95% CI, 0.22-0.75). Among patients given anti-TNF agents, stricturing (adjusted HR, 6.17; 95% CI, 2.81-13.54) and penetrating disease (adjusted HR, 3.39; 95% CI, 1.45-7.92) at the time of prescription were associated significantly with surgery. Older age at diagnosis (17-40 y) reduced the risk for abdominal surgery (adjusted HR, 0.41; 95% CI, 0.21-0.80) compared with a younger age group (≤16 y). Surgery before drug prescription reduced the risk for further surgeries among patients who received thiopurines (adjusted HR, 0.33; 95% CI, 0.13-0.68) or anti-TNF agents (adjusted HR, 0.49; 95% CI, 0.25-0.96). Terminal ileal disease location was not associated with a stricturing phenotype.

CONCLUSIONS

Based on a retrospective database analysis, patients prescribed thiopurine or anti-TNF therapy when they have a complicated stage of CD are more likely to require surgery. Better patient outcomes are achieved by treating CD at early inflammation stages; delayed treatment increases rates of treatment failure.

Methotrexate in combination with infliximab is no more effective than infliximab alone in patients with Crohn's disease

BACKGROUND & AIMS

Methotrexate and infliximab are effective therapies for Crohn's disease (CD). In the combination of maintenance methotrexate-infliximab trial, we evaluated the potential superiority of combination therapy over infliximab alone.

METHODS

In a 50-week, double-blind, placebo-controlled trial, we compared methotrexate and infliximab with infliximab alone in 126 patients with CD who had initiated prednisone induction therapy (15-40 mg/day) within the preceding 6 weeks. Patients were assigned randomly to groups given methotrexate at an initial weekly dose of 10 mg, escalating to 25 mg/week (n = 63), or placebo (n = 63). Both groups received infliximab (5 mg/kg of body weight) at weeks 1, 3, 7, and 14, and every 8 weeks thereafter. Prednisone was tapered, beginning at week 1, and discontinued no later than week 14. The primary outcome was time to treatment failure, defined as a lack of prednisone-free remission (CD Activity Index, <150) at week 14 or failure to maintain remission through week 50.

RESULTS

Patients' baseline characteristics were similar between groups. By week 50, the actuarial rate of treatment failure was 30.6% in the combination therapy group compared with 29.8% in the infliximab monotherapy group (P = .63; hazard ratio, 1.16; 95% confidence interval, 0.62-2.17). Prespecified subgroup analyses failed to show a benefit in patients with short disease duration or an increased level of C-reactive protein. No clinically meaningful differences were observed in secondary outcomes. Combination therapy was well tolerated.

CONCLUSIONS

The combination of infliximab and methotrexate, although safe, was no more effective than infliximab alone in patients with CD receiving treatment with prednisone. ClincialTrials.gov number, NCT00132899.

Distance management of inflammatory bowel disease: Systematic review and meta-analysis

AIM: To review the effectiveness of distance management methods in the management of adult inflammatory bowel disease (IBD) patients.

METHODS: A systematic review and meta-analysis of randomized controlled trials comparing distance management and standard clinic follow-up in the management of adult IBD patients. Distance management intervention was defined as any remote management method in which there is a patient self-management component whereby the patient interacts remotely via a self-guided management program, electronic interface, or self-directs open access to clinic follow up. The search strategy included electronic databases (Medline, PubMed, CINAHL, The Cochrane Central Register of Controlled Trials, EMBASE, KTPlus, Web of Science, and SCOPUS), conference proceedings, and internet search for web publications. The primary outcome was the mean difference in quality of life, and the secondary outcomes included mean difference in relapse rate, clinic visit rate, and hospital admission rate. Study selection, data extraction, and risk of bias assessment were completed by two independent reviewers.

RESULTS: The search strategy identified a total of 4061 articles, but only 6 randomized controlled trials met the inclusion and exclusion criteria for the systematic review and meta-analysis. Three trials involved telemanagement, and three trials involved directed patient self-management and open access clinics. The total sample size was 1463 patients. There was a trend towards improved quality of life in distance management patients with an end IBDQ quality of life score being 7.28 (95%CI: -3.25-17.81) points higher than standard clinic follow-up. There was a significant decrease in the clinic visit rate among distance management patients mean difference -1.08 (95%CI: -1.60--0.55), but no significant change in relapse rate or hospital admission rate.

CONCLUSION: Distance management of IBD significantly decreases clinic visit utilization, but does not significantly affect relapse rates or hospital admission rates.

Disease manifestations of Helicobacter pylori infection in Arctic Canada: using epidemiology to address community concerns

OBJECTIVES

Helicobacter pylori infection, linked to gastric cancer, is responsible for a large worldwide disease burden. H pylori prevalence and gastric cancer rates are elevated among indigenous Arctic communities, but implementation of prevention strategies is hampered by insufficient information. Some communities in northern Canada have advocated for H pylori prevention research. As a first step, community-driven research was undertaken to describe the H pylori-associated disease burden in concerned communities.

DESIGN

Participants in this cross-sectional study completed a clinical interview and gastroscopy with gastric biopsies taken for histopathological examination in February 2008.

SETTING

Study procedures were carried out at the health centre in Aklavik, Northwest Territories, Canada (population ∼600).

PARTICIPANTS

All residents of Aklavik were invited to complete a clinical interview and gastroscopy; 194 (58% female participants; 91% Aboriginal; age range 10-80 years) completed gastroscopy and had gastric biopsies taken.

PRIMARY AND SECONDARY OUTCOME MEASURES

This analysis estimates the prevalence of gastric abnormalities detected by endoscopy and histopathology, and associations of demographic and clinical variables with H pylori prevalence.

RESULTS

Among 194 participants with evaluable gastric biopsies, 66% were H pylori-positive on histology. Among H pylori-positive participants, prevalence was 94% for acute gastritis, 100% for chronic gastritis, 21% for gastric atrophy and 11% for intestinal metaplasia of the gastric mucosa, while chronic inflammation severity was mild in 9%, moderate in 47% and severe in 43%. In a multivariable model, H pylori prevalence was inversely associated with previous gastroscopy, previous H pylori therapy and aspirin use, and was positively associated with alcohol consumption.

CONCLUSIONS

In this population, H pylori-associated gastric histopathology shows a pattern compatible with elevated risk of gastric cancer. These findings demonstrate that local concern about health risks from H pylori is warranted and provide an example of how epidemiological research can address health priorities identified by communities.

Prevalence of Epstein-Barr Virus in a population of patients with inflammatory bowel disease: a prospective cohort study

BACKGROUND

The Epstein-Barr Virus (EBV) is truly prolific, with a prevalence of more than 90% in the adult human population. There are, however, little data available on the prevalence of EBV among patients with Inflammatory Bowel Disease (IBD), a population that is frequently immunosuppressed and thus at risk for severe, often fatal, primary infection.

AIM

To identify the prevalence of EBV in a population of patients with IBD and to compare it with that of the general population.

METHODS

A database of 2500 IBD patients previously followed at the University of Alberta IBD Centre was queried; 60 of these patients were randomly chosen to participate. A total of 220 patients attending the IBD Centre for clinical appointment were also prospectively asked to participate. Participants completed serological testing for VCA-IgM, VCA-IgG and EBNA-IgG, to determine prior EBV exposure.

RESULTS

A total of 263 patients underwent testing. Results for EBV seroprevalence of specific age groups were as follows: 18-20 years (n = 17), 29% seronegative; 21-25 years (n = 31), 29% seronegative; 26-30 years (n = 35), 31-35 years (n = 18) and 36-40 years (n = 25), 100% seropositive. Finally, 3% of those older than 40 (n = 117) were seronegative. EBV seroprevalence was similar for Crohn's disease and ulcerative colitis. Azathioprine was associated with seropositivity (P = 0.048).

CONCLUSION

The prevalence of EBV seronegativity in the IBD population aged 18-25 years was similar to that described in the general population, and above age 25 years, seropositivity approached 100%.

Review article: a clinician's guide for therapeutic drug monitoring of infliximab in inflammatory bowel disease

BACKGROUND

Tumour necrosis factor (TNF)-antagonists have an established role in the treatment of inflammatory bowel diseases (IBDs), however, subtherapeutic drug levels and the formation of anti-drug antibodies (ADAs) may decrease their efficacy.

AIM

The evidence supporting the use of therapeutic drug monitoring (TDM) based clinical algorithms for infliximab (IFX) and their role in clinical practice will be discussed.

METHODS

The literature was reviewed to identify relevant articles on the measurement of IFX levels and antibodies-to-infliximab.

RESULTS

Treatment algorithms for IBD have evolved from episodic monotherapy used in patients refractory to all other treatments, to long-term combination therapy initiated early in the disease course. Improved remission rates have been observed with this paradigm shift, nevertheless many patients ultimately lose response to therapy. Although empiric dose optimization or switching agents constitute the current standard of care for secondary failure, these interventions have not been applied in an evidence-based manner and are probably not cost-effective. Multiple TDM-based algorithms have been developed to identify patients that may benefit from measurement of IFX and ADA levels to guide adjustments to therapy.

CONCLUSIONS

Therapeutic drug monitoring offers a rational approach to the management of secondary failure to IFX. This concept has gained momentum based on evidence from case series, cohort studies and post-hoc analyses of randomised controlled trials.

Vedolizumab as induction and maintenance therapy for Crohn's disease

BACKGROUND

The efficacy of vedolizumab, an α4β7 integrin antibody, in Crohn's disease is unknown.

METHODS

In an integrated study with separate induction and maintenance trials, we assessed intravenous vedolizumab therapy (300 mg) in adults with active Crohn's disease. In the induction trial, 368 patients were randomly assigned to receive vedolizumab or placebo at weeks 0 and 2 (cohort 1), and 747 patients received open-label vedolizumab at weeks 0 and 2 (cohort 2); disease status was assessed at week 6. In the maintenance trial, 461 patients who had had a response to vedolizumab were randomly assigned to receive placebo or vedolizumab every 8 or 4 weeks until week 52.

RESULTS

At week 6, a total of 14.5% of the patients in cohort 1 who received vedolizumab and 6.8% who received placebo were in clinical remission (i.e., had a score on the Crohn's Disease Activity Index [CDAI] of ≤150, with scores ranging from 0 to approximately 600 and higher scores indicating greater disease activity) (P=0.02); a total of 31.4% and 25.7% of the patients, respectively, had a CDAI-100 response (≥100-point decrease in the CDAI score) (P=0.23). Among patients in cohorts 1 and 2 who had a response to induction therapy, 39.0% and 36.4% of those assigned to vedolizumab every 8 weeks and every 4 weeks, respectively, were in clinical remission at week 52, as compared with 21.6% assigned to placebo (P<0.001 and P=0.004 for the two vedolizumab groups, respectively, vs. placebo). Antibodies against vedolizumab developed in 4.0% of the patients. Nasopharyngitis occurred more frequently, and headache and abdominal pain less frequently, in patients receiving vedolizumab than in patients receiving placebo. Vedolizumab, as compared with placebo, was associated with a higher rate of serious adverse events (24.4% vs. 15.3%), infections (44.1% vs. 40.2%), and serious infections (5.5% vs. 3.0%).

CONCLUSIONS

Vedolizumab-treated patients with active Crohn's disease were more likely than patients receiving placebo to have a remission, but not a CDAI-100 response, at week 6; patients with a response to induction therapy who continued to receive vedolizumab (rather than switching to placebo) were more likely to be in remission at week 52. Adverse events were more common with vedolizumab. (Funded by Millennium Pharmaceuticals; GEMINI 2 ClinicalTrials.gov number, NCT00783692.).

A randomised phase I study of etrolizumab (rhuMAb β7) in moderate to severe ulcerative colitis

OBJECTIVE

Etrolizumab (rhuMAb β7, anti-β7, PRO145223) is a humanised monoclonal antibody targeting the β7 subunit of the heterodimeric integrins α4β7 and αEβ7, which are implicated in leucocyte migration and retention in ulcerative colitis (UC). This randomised phase I study evaluated the safety and pharmacology of etrolizumab in patients with moderate to severe UC.

DESIGN

In the single ascending dose (SAD) stage, etrolizumab (0.3, 1.0, 3.0, 10 mg/kg intravenous, 3.0 mg/kg subcutaneous (SC) or placebo) was administered 4:1 (n=25) in each cohort. In the multiple dose (MD) stage, new patients received monthly etrolizumab (0.5 mg/kg SC (n=4), 1.5 mg/kg SC (n=5), 3.0 mg/kg SC (n=4), 4.0 mg/kg intravenous (n=5)) or placebo (n=5). The pharmacokinetics was studied and Mayo Clinic Score evaluated at baseline, day 29 (SAD), and days 43 and 71 (MD).

RESULTS

In the SAD stage, there were no dose limiting toxicities, infusion or injection site reactions. Two impaired wound healing serious adverse events occurred in two patients receiving etrolizumab. In the MD stage, there were no dose limiting toxicities, and no infusion or injection site reactions. Headache was the most common adverse event, occurring more often in etrolizumab patients. Antietrolizumab antibodies were detected in two subjects. The duration of β7 receptor full occupancy was dose related. A clinical response was observed in 12/18 patients, and clinical remission in 3/18 patients treated with etrolizumab in the MD stage, compared with 4/5 and 1/5 placebo patients, respectively.

CONCLUSION

Etrolizumab is well tolerated in moderate to severe UC. Further investigation is warranted.