Etrasimod for the Treatment of Ulcerative Colitis: Analysis of Infection Events From the ELEVATE UC Clinical Program.

BACKGROUND AND AIMS: Infections are a safety concern in patients with ulcerative colitis (UC). Etrasimod is an oral, once-daily (QD), selective sphingosine 1phosphate (S1P)1,4,5 receptor modulator for the treatment of moderately to severely active UC. It leads to selective and reversible lymphocyte sequestration, and partial peripheral lymphocyte count decrease. We report infection events from the phase 3 ELEVATE program. METHODS: Proportions, incidence rates (IRs; per 100 patient-years) and descriptive analyses of all, serious, severe, herpes zoster, and opportunistic infections are reported in the Pivotal UC cohort (ELEVATE UC 52 and ELEVATE UC 12). Cox regression models evaluated potential baseline risk factors. RESULTS: In this analysis (n=787), proportions (IRs) of all infection events were similar for patients receiving etrasimod 2 mg QD (18.8% [41.1]) or placebo (17.7% [49.0]). Serious infections occurred in three (0.6%) and five (1.9%) patients receiving etrasimod and placebo, respectively. Two herpes zoster events were reported in each group (etrasimod: 0.4%; placebo: 0.8%); all localized and non-serious. One opportunistic infection event was reported in each group. No patient with an absolute lymphocyte count (ALC) <0.2 × 109/L reported serious/severe or opportunistic infections; no baseline risk factors were identified for such events. No deaths occurred. CONCLUSIONS: Patients receiving etrasimod demonstrated no increased risk of infection. The incidence of serious infections and herpes zoster was similar in each group. Among patients receiving etrasimod, no association between ALC <0.5 × 109/L and infection events was observed. Longer-term follow-up will further characterize the etrasimod safety profile.

IL-23 past, present, and future: a roadmap to advancing IL-23 science and therapy.

Interleukin (IL)-23, an IL-12 cytokine family member, is a hierarchically dominant regulatory cytokine in a cluster of immune-mediated inflammatory diseases (IMIDs), including psoriasis, psoriatic arthritis, and inflammatory bowel disease. We review IL-23 biology, IL-23 signaling in IMIDs, and the effect of IL-23 inhibition in treating these diseases. We propose studies to advance IL-23 biology and unravel differences in response to anti-IL-23 therapy. Experimental evidence generated from these investigations could establish a novel molecular ontology centered around IL-23-driven diseases, improve upon current approaches to treating IMIDs with IL-23 inhibition, and ultimately facilitate optimal identification of patients and, thereby, outcomes.

Extrachromosomal Circular DNA: An Emerging Potential Biomarker for Inflammatory Bowel Diseases?

Inflammatory bowel disease (IBD) comprising ulcerative colitis and Crohn's disease is a chronic immune-mediated disease which affects the gastrointestinal tract with a relapsing and remitting course, causing lifelong morbidity. IBD pathogenesis is determined by multiple factors including genetics, immune and microbial factors, and environmental factors. Although therapy options are expanding, remission rates are unsatisfiable, and together with the disease course, response to therapy remains unpredictable. Therefore, the identification of biomarkers that are predictive for the disease course and response to therapy is a significant challenge. Extrachromosomal circular DNA (eccDNA) fragments exist in all tissue tested so far. These fragments, ranging in length from a few hundreds of base pairs to mega base pairs, have recently gained more interest due to technological advances. Until now, eccDNA has mainly been studied in relation to cancer due to its ability to act as an amplification site for oncogenes and drug resistance genes. However, eccDNA could also play an important role in inflammation, expressed both locally in the- involved tissue and at distant sites. Here, we review the current evidence on the molecular mechanisms of eccDNA and its role in inflammation and IBD. Additionally, the potential of eccDNA as a tissue or plasma marker for disease severity and/or response to therapy is evaluated.

Two-Year Efficacy and Safety of Mirikizumab Following 104 Weeks of Continuous Treatment for Ulcerative Colitis: Results From the LUCENT-3 Open-Label Extension Study.

BACKGROUND: Mirikizumab, a p19-directed interleukin-23 monoclonal antibody, is efficacious in inducing clinical remission at week 12 (W12) and maintaining clinical remission at W52 in patients with moderately to severely active ulcerative colitis. Results are presented from the open-label extension study through W104. METHODS: Clinical, symptomatic, quality-of-life, and adverse event outcomes are reported for mirikizumab induction responders and extended induction responders, including biologic-failed patients, who entered LUCENT-3, with data shown for W52 maintenance responders or remitters. Discontinuations or missing data were handled by nonresponder imputation (NRI), modified NRI (mNRI), and observed case (OC). RESULTS: Among W52 mirikizumab responders, clinical response at W104 was 74.5%, 87.2%, and 96.7% and clinical remission was 76.6%, 89.0%, and 98.3% for NRI, mNRI, and OC, respectively. Among W52 mirikizumab remitters, clinical response at W104 was 54.0%, 62.8%, and 70.1% and clinical remission was 65.6%, 76.1%, and 84.2%. Using mNRI, remission rates at W104 for W52 clinical remitters were 74.7% corticosteroid-free, 79.5% endoscopic, 63.9% histologic-endoscopic mucosal remission, 85.9% symptomatic, 59.8% bowel urgency, 80.5% Inflammatory Bowel Disease Questionnaire (using NRI), 71.2% histologic-endoscopic mucosal improvement, and 77.5% bowel urgency improvement. Previous biologic-failed vs not-biologic-failed patient data were generally similar. Extended induction mNRI clinical response was 81.9%. Serious adverse events were reported in 5.2% of patients; 2.8% discontinued treatment due to adverse events. CONCLUSIONS: Endoscopic, histologic, symptomatic, and quality-of-life outcomes support the long-term benefit of mirikizumab treatment up to 104 weeks in patients with ulcerative colitis, including biologic-failed patients, with no new safety concerns.

Long-term clinical response/remission, endoscopic, histologic, and symptomatic data from an open-label study in patients with moderately to severely active ulcerative colitis demonstrate that 2-year continuous mirikizumab treatment maintained clinical remission in a majority of induction clinical responders, regardless of previous biologic failure status.

Early Life and Childhood Environmental Exposures, More Than Genetic Predisposition, Influence Age of Diagnosis in a Diverse Cohort of 2952 Patients With IBD.

BACKGROUND AND AIMS: Inflammatory bowel disease (IBD) develops from a combination of genetic and environmental factors. The aim of this study was to determine the contribution of established environmental risk factors and genetic risk on age of IBD diagnosis in a diverse cohort. METHODS: IBD patients in clinic completed detailed questionnaires. Blood was drawn for genetic analysis. Environmental risk factors and age of diagnosis were analyzed by ethnicity (Hispanic/Latinx or non-Hispanic White [NHW] individuals) and IBD subtype (ulcerative colitis or Crohn's disease [CD]). Weighted genetic risk scores and environmental risk scores were developed. We examined the relationship between environmental risk scores, genetic risk scores, and age of diagnosis. RESULTS: A total of 2952 patients were included: 58.9% had CD. A total of 46.83% were of Hispanic background. Early life exposures like cesarean delivery and being born in a developed country were associated with a younger age of IBD diagnosis. Childhood exposures such as frequent plastic water bottle use and having more than 1 bathroom at home were associated with a younger age of IBD. Hispanic and NHW individuals shared similar susceptibilities to environmental exposures. Environmental factors explained 21% of the variance in age of CD diagnosis and 39% in ulcerative colitis. In models incorporating genetic risk score and environmental risk score, the environment was the only significant factor associated with younger age of IBD diagnosis in all groups. CONCLUSIONS: Early life and childhood exposures impact IBD diagnosis and influence Hispanic and NHW individuals similarly. A cumulative environmental risk score contributes more to age of IBD diagnosis than genetic risk.

Safety of Ustekinumab in Inflammatory Bowel Disease: Pooled Safety Analysis Through 5 Years in Crohn's Disease and 4 Years in Ulcerative Colitis.

BACKGROUND AND AIMS: Previously published long-term safety data reported a favorable ustekinumab safety treatment profile for treatment of inflammatory bowel disease (IBD). We present the final cumulative safety data from pooled ustekinumab IBD phase 2/3 clinical studies through 5 years in Crohn's disease (CD) and 4 years in ulcerative colitis (UC). METHODS: In phase 3 studies, patients received a single IV placebo or ustekinumab (130mg or ~6mg/kg) induction dose followed by subcutaneous maintenance doses of placebo or ustekinumab (90mg q8w or q12w). Analyses included all patients who received one dose of study treatment and included patients who were biologic-naïve and patients with a history of biologic failure. Safety outcomes are summarized and presented using number of events per 100 patient-years of follow-up and corresponding 95% confidence interval. RESULTS: In this final pooled safety analysis, 2575 patients were treated with ustekinumab with 4826 patient-years of follow-up. Rates of key safety events, including MACE and malignancies, were similar between placebo and ustekinumab or not higher for ustekinumab.Opportunistic infections, including tuberculosis, and malignancies were reported infrequently. Rates of key safety events in the IBD group were no higher in the ustekinumab group than in the placebo group for both patients who were biologic naïve or who had previously failed a biologic. No lymphomas or cases of posterior reversible encephalopathy syndrome (PRES; formerly known as reversible posterior leukoencephalopathy syndrome [RPLS] were reported. CONCLUSION: The final cumulative ustekinumab safety data through 5 years in CD and 4 years in UC demonstrated favorable safety compared to placebo and continues to support the well-established safety profile across all approved indications.

Efficacy and Safety of Ustekinumab for Ulcerative Colitis Through 4 Years: Final Results of the UNIFI Long-Term Maintenance Study.

INTRODUCTION: Ulcerative colitis (UC) is a chronic condition that may require long-term treatment. We report the final efficacy and safety results of the UNIFI long-term extension study of ustekinumab in patients with UC through 4 years. METHODS: Ustekinumab induction responders who completed 44 weeks of maintenance treatment and agreed to enter the long-term extension continued their subcutaneous maintenance therapy (90 mg ustekinumab every 8 or 12 weeks [q8w or q12w] or placebo). Starting at week 56, randomized patients could receive dose adjustment to 90 mg q8w. Symptoms and adverse events were assessed through the study; endoscopic assessment was conducted at week 200. RESULTS: Of the 348 patients randomized to subcutaneous ustekinumab at maintenance baseline (q8w and q12w combined), 55.2% were in symptomatic remission at week 200. A greater proportion of biologic-naive patients (67.2% [117/174]) were in symptomatic remission than those with a history of biologic failure (41.6% [67/161]). Among patients in symptomatic remission at week 200, 96.4% were corticosteroid-free. Of the 171 patients with endoscopic evaluation at week 200, 81.6% (71/87) in the q12w group and 79.8% (67/84) in the q8w group had endoscopic improvement. From weeks 156 to the final safety visit (up to week 220), no deaths, major adverse cardiovascular events, or tuberculosis occurred in patients receiving ustekinumab. Nasopharyngitis, UC worsening, and upper respiratory tract infections were the most frequently reported adverse events. DISCUSSION: The long-term efficacy of ustekinumab maintenance in patients with UC was confirmed through 4 years. No new safety signals were observed. ClinicalTrials.gov number NCT02407236.

Efficacy and Safety of Approximately 3 Years of Continuous Ozanimod in Moderately to Severely Active Ulcerative Colitis: Interim Analysis of the True North Open-label Extension.

BACKGROUNDS AND AIMS: This interim analysis from the True North open-label extension [OLE] study examines efficacy and safety of approximately 3 years of continuous ozanimod treatment in patients with moderately to severely active ulcerative colitis. METHODS: Clinical responders after 52 weeks of ozanimod during the phase 3 True North study, who continued treatment in the OLE, were evaluated. Efficacy, including endoscopic and histological endpoints, was assessed during the OLE for approximately 2 additional years through OLE Week 94, using observed case [OC] and nonresponder imputation [NRI] analyses. Adverse events were monitored from True North baseline through OLE data cutoff and expressed as exposure-adjusted incidence rates. RESULTS: This analysis included 131 patients; 54% had achieved corticosteroid-free remission at True North Week 52. In OC analyses, clinical response, clinical remission, and corticosteroid-free remission were achieved by 91.4%, 69.1%, and 67.9% of patients, respectively, at OLE Week 94 [146 weeks of total treatment]. Similarly, endoscopic improvement, histological remission, and mucosal healing were achieved by 73.3%, 67.3%, and 56.3% of patients, respectively, at OLE Week 94. Efficacy rates were lower using NRI analyses, but maintenance of efficacy was demonstrated through OLE Week 94. No new safety signals emerged from this analysis. Serious infections, malignancy, cardiovascular events, and hepatic events occurred infrequently. CONCLUSIONS: Among patients who achieved clinical response after 1 year of ozanimod treatment during True North, a high percentage sustained clinical and mucosal efficacy over 2 additional years in the OLE. No new safety signals were observed with long-term ozanimod use.

Maintenance Risankizumab Sustains Induction Response in Patients with Crohn's Disease in a Randomized Phase 3 Trial.

BACKGROUND AND AIMS: Durable clinical remission, endoscopic healing, and biomarker normalization are key treatment goals for Crohn's disease. The selective anti-interleukin-23 p19 inhibitor risankizumab has demonstrated efficacy and safety in moderately to severely active Crohn's disease. This post-hoc analysis of data from the pivotal risankizumab maintenance study assessed whether risankizumab maintenance therapy sustained the clinical and endoscopic outcomes achieved with risankizumab induction therapy. METHODS: We evaluated 462 patients who achieved a clinical response to risankizumab intravenous induction treatment and were re-randomized to receive subcutaneous risankizumab 360 mg, subcutaneous risankizumab 180 mg, or placebo [withdrawal] every 8 weeks for 52 weeks in the randomized, controlled FORTIFY maintenance study. Maintenance of clinical, endoscopic, and biomarker endpoints at week 52 among patients who achieved these endpoints after 12 weeks of induction treatment was evaluated. RESULTS: A significantly higher proportion of patients receiving maintenance treatment with risankizumab 360 or 180 mg compared with placebo [withdrawal] maintained Crohn's Disease Activity Index remission [68.6%, 70.8%, vs 56.3%; p < 0.05], stool frequency/abdominal pain remission [69.2%, 64.1%, vs 50.5%; p < 0.01], endoscopic response [70.2%, 68.2%, vs 38.4%; p < 0.001], endoscopic remission [74.4%, 45.5%, vs 23.9%; p < 0.05], and Simple Endoscopic Score for Crohn's Disease of 0-2 [65.5%, 36.7%, vs 21.9%]. Most patients [56.8-83.3%] who achieved normalized faecal calprotectin or C-reactive protein during induction sustained them with maintenance risankizumab. CONCLUSIONS: Subcutaneous risankizumab maintenance therapy results in durable improvement in clinical and endoscopic outcomes over 1 year in patients with moderately to severely active Crohn's disease. CLINICAL TRIAL REGISTRATION NUMBER: NCT03105102.

Colorectal Cancer Immunotherapy: State of the Art and Future Directions.

Cancer immunotherapy has become an indispensable mode of treatment for a multitude of solid tumor cancers. Colorectal cancer (CRC) has been one of the many cancer types to benefit from immunotherapy, especially in advanced disease where standard treatment fails to prevent recurrence or results in poor survival. The efficacy of immunotherapy in CRC has not been without challenge, as early clinical trials observed dismal responses in unselected CRC patients treated with checkpoint inhibitors. Many studies and clinical trials have since refined immunotherapies available for CRC, solidifying immunotherapy as a powerful asset for CRC treatment. This review article examines CRC immunotherapies, from their foundation, through emerging avenues for improvement, to future directions.

Outcomes and endpoints of postoperative recurrence in Crohn's Disease: systematic review and consensus conference.

BACKGROUND: Outcomes after ileocolonic resection in Crohn's Disease (CD) are heterogeneous and a clear definition of postoperative recurrence remains to be determined. Our Endpoints Working Group of the International Organization for the study of Inflammatory Bowel Disease (IOIBD) aimed to standardize postoperative outcomes, to discuss which endpoints should be used for postoperative clinical trials and to define those which could be used in trials or registries. METHODS: Based on a systematic review of the literature, recommendations and statements were drafted and sent to all IOIBD members for a first round of voting. Recommendations and statements were revised based on the voters' comments during a consensus hybrid conference open to all IOIBD members. If no agreement was reached after 2 rounds of voting, the statement was excluded. RESULTS: In the systematic review, 3,071 manuscripts were screened, of which 434 were included. Sixteen recommendations were identified, of which 11 were endorsed. Recommendations and statements include that endoscopy remains the gold standard and should be used as a short-term primary endpoint in both observational cohorts and randomized controlled trials. Clinical symptoms classically used in clinical trials for luminal CD are not reliable in this specific situation. For that reason, longer term endpoints should be based on the evidence of macroscopic inflammation assessed by imaging techniques, endoscopy or reflected by the presence of complications. CONCLUSIONS: Agencies recommend the use of clinical evaluations, as in the case of luminal CD, and do not recognize primary endpoints based solely on endoscopy. This consensus has led to agreement on the need to define postoperative endoscopy- and/or imaging-based endpoints.

Analysis of Clinical Trial Screen Failures in Inflammatory Bowel Diseases (IBD): Real World Results from the International Organization for the study of IBD.

BACKGROUND: Recruitment for randomized controlled trials (RCTs) in IBD have substantially dropped over time. This study aimed to assess reasons why IBD patients are not included in sponsored multicenter phase IIb-III RCTs. METHODS: All IOIBD members (n=58) were invited to participate. We divided barriers to participation as follow: 1) reasons patients with active IBD were not deemed appropriate for a RCT; 2) reasons qualified patients did not wish to participate; 3) reasons for screen failure (SF) in patients agreeing to participate. We assess those in a 4-week prospective study including, consecutively, all patients with symptomatic disease for whom a treatment change was required. In addition, we performed a 6-month retrospective study to further evaluate reasons for SF. RESULTS: A total of 106 patients (60 male (56.6%), 63 Crohn's disease [CD] (59.4%)), from 10 centers across the world, were included in the prospective study. A RCT has not been proposed to 65 of them (mainly due to eligibility criteria). Of the 41 patients to whom a RCT was offered, 8 refused (mainly due to reluctance to receive placebo) and 28 agreed to participate. Among these 28 patients, 5 failed their screening and 23 were finally included in a RCT. A total of 107 patients (61 male (57%), 67 CD (62.6%)), from 13 centers worldwide, were included in our retrospective study of SFs. The main reason was insufficient disease activity. CONCLUSION: This first multicenter study analyzing reasons for non-enrollment in IBD RCTs shown that we lose patients at each step. Eligibility criteria, the risk of placebo assignment and insufficient disease activity were part of the main barriers.

Current and Novel Uses of Intestinal Ultrasound in Inflammatory Bowel Disease.

Intestinal ultrasound (IUS) is a patient-centric, noninvasive, real-time, point-of-care tool with the capability to aid in diagnosis and monitoring of disease activity in both Crohn's disease and ulcerative colitis without the need for bowel preparation. IUS can be used as a tool for precision monitoring of inflammatory bowel disease (IBD) treatment response. IUS as a cross-sectional imaging tool is as accurate as magnetic resonance enterography (MRE) for assessing the ileum and is more accurate than MRE for colonic assessment proximal to the rectum. Multiple simple ultrasound-based scoring systems have been internally validated with endoscopy in both Crohn's disease and ulcerative colitis, and changes in IUS parameters can be seen as early as 2 weeks after treatment initiation. IUS also plays a unique role in IBD activity monitoring of patients in whom avoidance of invasive testing is paramount, such as children and pregnant patients. Novel uses go beyond monitoring activity, with potential use of elastography to measure bowel wall stiffness to detect fibrosis and bowel damage for enhanced decision-making. Ultimately, IUS is likely to expand in the United States, facilitated by accessible expert training, access to equipment, and the development of a reimbursement model. This article provides a comprehensive review of the current and novel uses of IUS in IBD.

Difficult-to-treat inflammatory bowel disease: results from an international consensus meeting.

Many patients with inflammatory bowel disease (IBD) have persistent symptoms and disease activity despite the best available medical or surgical treatments. These patients are commonly referred to as having difficult-to-treat IBD and need additional therapeutic strategies. However, the absence of standard definitions has impeded clinical research efforts and comparisons of data. Under the guidance of the endpoints cluster of the International Organization for the Study of Inflammatory Bowel Disease, we held a consensus meeting to propose a common operative definition for difficult-to-treat IBD. 16 participants from 12 countries voted on 20 statements covering various elements of difficult-to-treat IBD, such as failure of medical and surgical treatments, disease phenotypes, and specific complaints from patients. "Agreement" was defined as at least 75% consensus. The group agreed that difficult-to-treat IBD is defined by the failure of biologics and advanced small molecules with at least two different mechanisms of action, or postoperative recurrence of Crohn's disease after two surgical resections in adults, or one in children. In addition, chronic antibiotic-refractory pouchitis, complex perianal disease, and comorbid psychosocial complications that impair disease management also qualified as difficult-to-treat IBD. Adoption of these criteria could serve to standardise reporting, guide enrolment in clinical trials, and help identify candidates for enhanced treatment strategies.

Correlation of mucosal healing endpoints with long-term clinical and patient-reported outcomes in ulcerative colitis.

BACKGROUND: We evaluated the clinical relevance of achieving histologic endoscopic mucosal improvement (HEMI) and the more stringent target of histologic endoscopic mucosal remission (HEMR) in the phase 3 maintenance trial of upadacitinib for moderately to severely active ulcerative colitis. METHODS: Clinical and patient-reported outcomes were assessed in patients with clinical response after 8- or 16-week upadacitinib induction who received 52-week upadacitinib maintenance treatment. Cross-sectional and predictive analyses evaluated the relationship between HEMR or HEMI at Week 8/16 and Week 52, respectively, and outcomes at Week 52. Adjusted odds ratios (aOR) were derived from logistic regressions for patients achieving HEMR or HEMI without HEMR versus those not achieving HEMI. RESULTS: Cross-sectional analyses showed that patients with HEMR had greater odds of achieving all clinical and patient-reported outcomes at Week 52 than those not achieving HEMI. In predictive analyses, patients with HEMR at Week 8/16 had significantly greater odds of achieving clinical remission (aOR = 3.6, p = 0.001) and endoscopic remission (aOR = 3.9, p < 0.001) at Week 52 than patients not achieving HEMI and HEMR. For patients achieving HEMI without HEMR, these odds were lower: clinical remission (aOR = 3.2, p < 0.001) and endoscopic remission (aOR = 2.4, p = 0.010). The odds of achieving clinically meaningful improvements in most patient-reported outcomes were directionally similar between HEMI and HEMR, but not statistically different to patients not achieving HEMI. No hospitalizations or surgeries were observed in patients with HEMR at Week 52. CONCLUSIONS: Achievement of HEMR or HEMI is clinically relevant with HEMR being associated with greater likelihood of improvement in long-term clinical and patient-reported outcomes. https://www. CLINICALTRIALS: gov NCT02819635.

Higher Intra-Abdominal Visceral Adipose Tissue Mass Is Associated With Lower Rates of Clinical and Endoscopic Remission in Patients With Inflammatory Bowel Diseases Initiating Biologic Therapy: Results of the Constellation Study.

BACKGROUND & AIMS: We sought to assess the association between intra-abdominal visceral adipose tissue (IA-VAT) and response to 3 different biologic drugs in patients with inflammatory bowel disease (IBD) and to investigate its effects on inflammatory cytokine expression, pharmacokinetics, and intestinal microbiota. METHODS: We prospectively enrolled subjects with active IBD initiating infliximab, vedolizumab, or ustekinumab and a healthy control group. Baseline body composition (including IA-VAT as percent of total body mass [IA-VAT%]) was measured using GE iDXA scan. Primary outcome was corticosteroid- free deep remission at weeks 14-16, defined as Harvey Bradshaw Index <5 for Crohn's disease and partial Mayo score <2 for ulcerative colitis, with a normal C-reactive protein and fecal calprotectin. Secondary outcomes were corticosteroid-free deep remission and endoscopic remission (Endoscopic Mayo Score ≤1 in ulcerative colitis or Simple Endoscopic Score for Crohn's disease ≤2) at weeks 30-46. RESULTS: A total of 141 patients with IBD and 51 healthy controls were included. No differences in body composition parameters were seen between the IBD and healthy control cohorts. Patients with higher IA-VAT% were less likely to achieve corticosteroid-free deep remission (P < .001) or endoscopic remission (P = .02) vs those with lower IA-VAT%. Furthermore, nonresponders with high IA-VAT% had significantly higher serum interleukin-6 and tumor necrosis factor at baseline compared with responders and patients with low IA-VAT%. Drug pharmacokinetic properties and microbiota diversity were similar when comparing high and low IA-VAT% groups. CONCLUSIONS: Higher IA-VAT% was independently associated with worse outcomes. This association could be driven at least partially by discrete differences in inflammatory cytokine expression.

Intestinal Epithelial Inactivity of Dual Oxidase 2 Results in Microbiome-Mediated Metabolic Syndrome.

BACKGROUND & AIMS: Metabolic syndrome (MetS) is characterized by obesity, glucose intolerance, and hepatic steatosis. Alterations in the gut microbiome play important roles in the development of MetS. However, the mechanisms by which this occurs are poorly understood. Dual oxidase 2 (DUOX2) is an antimicrobial reduced nicotinamide adenine dinucleotide phosphate oxidase expressed in the gut epithelium. Here, we posit that epithelial DUOX2 activity provides a mechanistic link between the gut microbiome and the development of MetS. METHODS: Mice carrying an intestinal epithelial-specific deletion of dual oxidase maturation factor 1/2 (DA IEC-KO), and wild-type littermates were fed a standard diet and killed at 24 weeks. Metabolic alterations were determined by glucose tolerance, lipid tests, and body and organ weight measurements. DUOX2 activity was determined by Amplex Red. Intestinal permeability was determined by fluorescein isothiocyanate-dextran, microbial translocation assessments, and portal vein lipopolysaccharide measurements. Metagenomic analysis of the stool microbiome was performed. The role of the microbiome was assessed in antibiotic-treated mice. RESULTS: DA IEC-KO males showed increased body and organ weights accompanied by glucose intolerance and increased plasma lipid and liver enzyme levels, and increased adiposity in the liver and adipose tissue. Expression of F4/80, CD68, uncoupling protein 1, carbohydrate response element binding protein, leptin, and adiponectin was altered in the liver and adipose tissue of DA IEC-KO males. DA IEC-KO males produced less epithelial H2O2, had altered relative abundance of Akkermansiaceae and Lachnospiraceae in stool, and showed increased portal vein lipopolysaccharides and intestinal permeability. Females were protected from barrier defects and MetS, despite producing less H2O2. Antibiotic depletion abrogated all MetS phenotypes observed. CONCLUSIONS: Intestinal epithelial inactivity of DUOX2 promotes MetS in a microbiome-dependent manner.

Patients With Inflammatory Bowel Diseases and Higher Visceral Adipose Tissue Burden May Benefit From Higher Infliximab Concentrations to Achieve Remission.

INTRODUCTION: In patients with inflammatory bowel diseases (IBDs), high visceral adipose tissue (VAT) burden is associated with a lower response to infliximab, potentially through alterations in volume distribution and/or clearance. Differences in VAT may also explain the heterogeneity in target trough levels of infliximab associated with favorable outcomes. The aim of this study was to assess whether VAT burden may be associated with infliximab cutoffs associated with efficacy in patients with IBD. METHODS: We conducted a prospective cross-sectional study of patients with IBD receiving maintenance infliximab therapy. We measured baseline body composition parameters (Lunar iDXA), disease activity, trough levels of infliximab, and biomarkers. The primary outcome was steroid-free deep remission. The secondary outcome was endoscopic remission within 8 weeks of infliximab level measurement. RESULTS: Overall, 142 patients were enrolled. The optimal trough levels of infliximab cutoffs associated with steroid-free deep remission and endoscopic remission were 3.9 mcg/mL (Youden Index [J]: 0.52) for patients in the lowest 2 VAT % quartiles (<1.2%) while optimal infliximab level cutoffs associated with steroid-free deep remission for those patients in the highest 2 VAT % quartiles was 15.3 mcg/mL (J: 0.63). In a multivariable analysis, only VAT % and infliximab level remained independently associated with steroid-free deep remission (odds ratio per % of VAT: 0.3 [95% confidence interval: 0.17-0.64], P < 0.001 and odds ratio per µg/mL: 1.11 [95% confidence interval: 1.05-1.19], P < 0.001). DISCUSSION: The results may suggest that patients with higher visceral adipose tissue burden may benefit from achieving higher infliximab levels to achieve remission.