Infliximab Tissue Concentrations in Patients With Stable Ulcerative Colitis Are Correlated With More Durable Infliximab-associated Disease Remission.

BACKGROUND: We aimed to determine the correlation between tissue and plasma infliximab concentrations in an outpatient ulcerative colitis (UC) cohort based on histologic disease activity in addition to their relationship with long-term clinical outcomes. We assessed intraparticipant variability in infliximab concentrations between adjacent intestinal samples and the correlation between disease activity and tumor necrosis factor-α (TNF-α). METHODS: A prospective cohort study was conducted in participants with UC receiving infliximab. Blood and 2 sigmoid colon biopsies were obtained at the index colonoscopy for infliximab and TNF-α quantification. Histological disease activity was assessed. Participants were followed for 2 years for the occurrence of hospitalization, surgery, disease relapse, and infliximab discontinuation. RESULTS: A positive correlation was observed between mean plasma and uninflamed tissue infliximab concentrations only (Rs = 0.75, P = .0071). Lower mean tissue infliximab concentrations correlated with a shorter time to disease relapse vs those with higher mean tissue concentrations (Rs = 0.77, P = .032). This was not seen when using plasma infliximab concentrations. Additionally, no significant intraparticipant variability of infliximab concentrations was observed for all participants independent of disease activity. Neither plasma nor tissue TNF-α correlated with disease activity. CONCLUSIONS: These findings support data generated in patients with Crohn's disease: plasma infliximab concentrations are reflective of infliximab exposure in tissue in the UC patient in remission, but not for those with active disease. Increasing tissue concentrations in the noninflamed tissues may improve durability of infliximab. Neither plasma nor tissue TNF-α appear to correlate with UC disease activity. Larger follow-up studies would be of benefit.

Plasma infliximab concentrations are reflective of infliximab exposure in tissue in the UC patient in remission, but not for those with active disease. Increasing tissue concentrations in the noninflamed tissues may improve durability of infliximab.

Determining the optimal treatment target in patients with ulcerative colitis: rationale, design, protocol and interim analysis for the randomised controlled VERDICT trial.

INTRODUCTION: Symptoms, endoscopy and histology have been proposed as therapeutic targets in ulcerative colitis (UC). Observational studies suggest that the achievement of histologic remission may be associated with a lower risk of complications, compared with the achievement of endoscopic remission alone. The actiVE ulcerative colitis, a RanDomIsed Controlled Trial (VERDICT) aims to determine the optimal treatment target in patients with UC. METHODS AND ANALYSIS: In this multicentre, prospective randomised study, 660 patients with moderate to severe UC (Mayo rectal bleeding subscore [RBS] ≥1; Mayo endoscopic score [MES] ≥2) are randomly assigned to three treatment targets: corticosteroid-free symptomatic remission (Mayo RBS=0) (group 1); corticosteroid-free endoscopic remission (MES ≤1) and symptomatic remission (group 2); or corticosteroid-free histologic remission (Geboes score <2B.0), endoscopic remission and symptomatic remission (group 3). Treatment is escalated using vedolizumab according to a treatment algorithm that is dependent on the patient's baseline UC therapy until the target is achieved at weeks 16, 32 or 48. The primary outcome, the time from target achievement to a UC-related complication, will be compared between groups 1 and 3 using a Cox proportional hazards model. ETHICS AND DISSEMINATION: The study was approved by ethics committees at the country level or at individual sites as per individual country requirements. A full list of ethics committees is available on request. Study results will be disseminated in peer-reviewed journals and at scientific meetings. TRIAL REGISTRATION NUMBER: EudraCT: 2019-002485-12; NCT04259138.

Long Washout Periods Between Biologics for Inflammatory Bowel Disease Clinical Trials Are Unnecessary: A Canadian Retrospective Cohort Study.

INTRODUCTION: To assess the safety of early vs late biologic switch in patients with inflammatory bowel disease. METHODS: In this retrospective study, we included patients with inflammatory bowel disease who underwent biologic switch between January 2014 and July 2022 at a tertiary center. The primary outcome was any infection by 6 months. RESULTS: There was no statistically significant difference between patients who had early biologic switch (≤30 days, n = 51) and late switch (>30 days, n = 77) in either infectious or noninfectious adverse events by 6 and 12 months. DISCUSSION: Early biologic switch is safe. A prolonged washout period between 2 biologics is unnecessary.

Systematic review and meta-analysis of randomised controlled trials: Medical therapies for the treatment and prevention of pouchitis.

BACKGROUND AND AIMS: We conducted a systematic review to assess medical therapy for the treatment and prevention of pouchitis. METHODS: Randomised controlled trials (RCTs) of medical therapy in adults with or without pouchitis were searched to March 2022. Primary outcomes included clinical remission/response, maintenance of remission and prevention of pouchitis. RESULTS: Twenty RCTs (N = 830) were included. Acute pouchitis: One study compared ciprofloxacin with metronidazole. At 2 weeks, 100% (7/7) of ciprofloxacin participants achieved remission, compared with 67% (6/9) of metronidazole participants (RR: 1.44, 95% CI: 0.88-2.35, very low certainty evidence). One study compared budesonide enemas with oral metronidazole. Fifty percent (6/12) of budesonide participants achieved remission compared with 43% (6/14) of metronidazole participants (RR: 1.17, 95% CI: 0.51-2.67, low certainty evidence). Chronic pouchitis: Two studies (n = 76) assessed De Simone Formulation. Eighty-five percent (34/40) of De Simone Formulation participants maintained remission at 9-12 months compared with 3% (1/36) placebo participants (RR: 18.50, 95% CI: 3.86-88.56, moderate certainty evidence). One study assessed vedolizumab. Thirty-one percent (16/51) of vedolizumab participants achieved clinical remission at 14 weeks compared with 10% (5/51) of placebo participants (RR: 3.20, 95% CI: 1.27-8.08, moderate certainty evidence). PROPHYLAXIS: Two studies assessed De Simone Formulation. Ninety percent (18/20) of De Simone Formulation participants did not develop pouchitis compared with 60% (12/20) of placebo participants (RR: 1.50, 95% CI: 1.02-2.21, moderate certainty evidence). CONCLUSIONS: Apart from vedolizumab and the De Simone formulation, the effects of other medical interventions for pouchitis are uncertain.

Clinical, Endoscopic, and Radiological Effectiveness of Ustekinumab in Bio-naïve Versus Bio-experienced Patients With Crohn's Disease: Real-world Experience From a Large Canadian Center.

INTRODUCTION: With the expanding therapeutic armamentarium for inflammatory bowel disease (IBD), real-world data may help inform drug positioning. We assessed clinical, endoscopic, imaging, and biochemical response/remission outcomes in patients with Crohn's disease (CD) treated with ustekinumab in a large Canadian IBD center. METHODS: A retrospective cohort study of CD patients was treated with ustekinumab. Clinical, endoscopic, radiological, and biochemical response and remission outcomes were stratified by prior biologic exposure status. Hazard ratios for biologic exposure status were estimated using Cox proportional hazard models and subgroup-specific incidence rates for healing. RESULTS: A total of 231 patients (55.9% female, median 45.8 years) were identified as receiving ustekinumab during the study period, with 2 patients subsequently excluded (N = 229). Of these patients, 79.0% (181 of 229) were bio-experienced, with 38.7% (70 of 181) having failed 1 biologic and 61.3% (111 of 181) having failed ≥2 biologics. At 3 months of follow-up after induction, clinical remission (Harvey-Bradshaw Index ≤4) was achieved by 59.1% (62 of 105) of bio-experienced patients and 79.4% (27 of 34) of bio-naïve patients (relative risk [RR], 1.34; 95% CI, 1.06-1.70; P = .013). Endoscopic remission (absence of mucosal ulcers) was achieved in 37.9% (33 of 87) cases. Rate of endoscopic healing (either endoscopic response or remission) per 1000 person-months was 72.7 (95% CI, 42.4-125.1) and 50.2 (37.9-66.4); and the median time to endoscopic response was 8.4 months (95% CI, 6.4-9.8) and 15.4 months (95% CI, 10.3-17.9) in bio-naïve vs bio-experienced patients, respectively. Imaging response/remission and steroid-free remission rates were higher in bio-naïve patients. CONCLUSION: In this large real-world cohort of CD patients with complex phenotypes and high rates of prior biologic exposure, we observed that ustekinumab was effective and safe with higher rates of improvement in bio-naïve subjects across a range of end points.

In this large real-world study of patients with Crohn's Disease treated with ustekinumab, we observed high rates of clinical, endoscopic, radiological, and biochemical response and remission rates. Effectiveness was greater in bio-naïve compared with bio-experienced patients.

Decreased Infliximab Concentrations in Patients With Inflammatory Bowel Disease Who Carry a Variable Number Tandem Repeat Polymorphism in the Neonatal Fc Receptor or Variant HLADQA1*05G>A Genotype.

BACKGROUND: Multiple variables contribute to variation in patient exposure and response to tumor necrosis factor alpha antagonist biologics such as infliximab. This study aimed to assess the association between maintenance-phase infliximab concentrations and genetic variation in HLADQA1*05G>A and fragment crystallisable (Fc) fragment of IgG receptor and transporter (FCGRT) among patients with inflammatory bowel disease. METHODS: A cross-sectional study was carried out in participants with inflammatory bowel disease prescribed infliximab who were in the maintenance phase of treatment. Participants were genotyped for the presence of the FCGRT variable number tandem repeat (VNTR) and HLADQA1*05G>A (rs74291249). A point estimate of the infliximab trough concentration during the maintenance phase was determined using a standard enzyme-linked immunosorbent assay for each patient. Other variables associated with infliximab pharmacokinetics were collected. RESULTS: A total of 156 participants with inflammatory bowel disease were included from 2 tertiary care centers affiliated with Western University, London, Canada. Median infliximab trough concentrations were lower in participants who carried the FCGRT VNTR 2/3 or 2/2 (4.14 µg/mL; interquartile range [IQR], 6.48 µg/mL) vs wild type individuals (7.00 µg/mL; IQR, 7.66; P = .0027). Median infliximab trough concentrations were significantly lower in participants who were HLADQA1*05G>A variant carriers (4.73µg/mL; IQR, 4.79) vs wild type individuals (7.85µg/mL; IQR, 7.44; P = .0006). A significant decrease in infliximab trough concentrations was seen in individuals who were dual carriers of variant polymorphisms in HLADQA1*05G>A and FCGRT VNTR (no variants, 8.96µg/mL; IQR, 6.84 vs one variant, 4.96 µg/mL; IQR, 4.95 vs dual variants, 0.86µg/mL; IQR, 5.82). CONCLUSION: FCGRT VNTR and HLADQA1*05G>A are associated with lower maintenance-phase infliximab concentrations, particularly among patients who carry both variants.

HLADQA1*05G>A and FCGRT VNTR are associated with lower maintenance-phase infliximab concentrations, particularly among patients who carry both variants.

High oncostatin M predicts lack of clinical remission for patients with inflammatory bowel disease on tumor necrosis factor α antagonists.

The interleukin-6 family cytokine, oncostatin-M (OSM) has been associated with response to tumor necrosis factor-α antagonists (anti-TNFs) in small cohorts of patients with inflammatory bowel disease (IBD). We aimed to evaluate the association between plasma OSM concentrations and response to anti-TNFs (infliximab and adalimumab) in both ulcerative colitis (UC) and Crohn's disease (CD). A retrospective cohort study was conducted in patients with IBD with a history of anti-TNF exposure. Blood samples, collected prior to anti-TNF exposure, were analyzed by enzyme-linked immunosorbent assay for the presence and quantity of OSM. Clinical remission was assessed at 1-year post anti-TNF exposure in addition to the occurrence of surgery, hospitalization, corticosteroid use, and adverse drug events. Lastly the threshold OSM plasma concentration associated with anti-TNF non-response was assessed by receiver operator characteristic (ROC) curve analysis. Patients with IBD (CD, n = 82; UC, n = 40) were assessed. In both UC and CD, mean pre-treatment OSM concentrations were significantly lower in those who achieved clinical remission at 1-year (p < 0.0001). A threshold plasma OSM concentration of 168.7 pg/ml and 233.6 pg/ml respectively separated those who achieved clinical remission at 1-year on an anti-TNF from those who did not in CD and UC respectively (CD: area under the receiver operator characteristic curve, AUROC = 0.880, 95% CI 0.79-0.96; UC: AUROC = 0.938, 95% CI 0.87-1.00). High OSM concentrations were associated with anti-TNF discontinuation and use of rescue steroids in CD and UC. High pre-treatment OSM concentrations identify IBD patients at-risk of anti-TNF non-response at 1-year as well as other deleterious clinical outcomes.

Pretreatment HLADQA1-HLADRB1 Testing for the Prevention of Azathioprine-Induced Pancreatitis in Inflammatory Bowel Disease: A Prospective Cohort Study.

INTRODUCTION: Azathioprine-induced pancreatitis is an idiosyncratic and unpredictable response, occurring in up to 7% of azathioprine-exposed patients with inflammatory bowel disease (IBD). The haplotype HLADQA1-HLADRB1*07:01A>C is strongly associated with azathioprine-induced pancreatitis in IBD. We aimed to evaluate whether pretreatment HLADQA1-HLADRB1*07:01A>C screening will reduce the risk of azathioprine-induced pancreatitis. METHODS: Participants with IBD were screened for HLADQA1-HLADRB1*07:01A>C, and participants with a variant genotype were excluded from azathioprine treatment. Wild-type participants were started on azathioprine and followed for 3 months. The incidence of pancreatitis was compared with unscreened historical controls. RESULTS: HLADQA1-HLADRB1*07:01A>C screening resulted in an 11-fold reduction in the incidence of azathioprine-induced pancreatitis (n = 1/328 or 0.30% vs n = 13/373 or 3.4%). In propensity score-matched cohorts (age and sex), HLA DQA1-HLADRB1*07:01A>C screening was significantly associated with a reduction in the incidence of AZA-induced pancreatitis independent of weight, glucocorticoid exposure, and smoking status (adjusted odds ratio = 0.075, 95% confidence interval = 0.01-0.58, P = 0.01). Up to 45% (n = 271/599) of participants were excluded from azathioprine therapy based on the haplotype in the HLADQA1-HLADRB1*07:01A>C-screened cohort. DISCUSSION: HLADQA1-HLADRB1*07:01A>C screening reduced the risk of azathioprine-induced pancreatitis; however, using this strategy to guide the use of azathioprine therapy in IBD may eliminate a large proportion of patients from being eligible for treatment with azathioprine. In regions where there is access to other IBD therapies, and given the short-term and long-term toxicities associated with azathioprine, HLADQA1-HLADRB1*07:01A>C-screening may be a clinically relevant strategy for enhancing the safe use of azathioprine in IBD. In addition, cost-effectiveness analyses are needed to further solidify the utility of HLADQA1-HLADRB1*07:01A>C screening in IBD populations.

High infliximab trough concentrations are associated with sustained histologic remission in inflammatory bowel disease: a prospective cohort study.

BACKGROUND: The threshold concentration of infliximab during maintenance therapy has not been well-defined in relation to histologic remission. The aim of the study is to dentify the maintenance-phase infliximab concentration associated with histologic remission in inflammatory bowel disease patients (IBD). METHODS: A prospective cohort study was carried out in 104 IBD patients seen at a tertiary care centre in London, Canada. Infliximab trough concentrations were collected during the maintenance phase of treatment and compared between participants with and without evidence of histologic remission. Participants were additionally evaluated for sustained histologic remission, and relapse to active disease. RESULTS: Participants in histologic remission attained higher mean concentrations of infliximab during the maintenance phase (10.34 ± 0.69 µg/ml) compared to those with persistent disease activity (6.23 ± 0.67 µg/ml, p-value < 0.0001). Additionally, during the maintenance phase, sustained histologic remission was also associated with a higher mean concentration of infliximab (10.81 ± 5.46 µg/ml) compared to those who relapsed to active disease (5.68 ± 3.70, p < 0.001). Overall, participants with a mean infliximab trough concentration greater than 8ug/ml were more likely to have histologic remission (area under the receiver operating characteristic curve, AUROC = 0.72, 95%CI = 0.65-0.84, p < 0.0001) and sustained histologic remission (AUC = 0.77, 95%CI = 0.63-0.91, p = 0.002). CONCLUSION: Maintenance-phase infliximab trough concentrations greater than 8 µg/ml, which is higher than the currently recommended target concentration, are highly associated with histologic remission and sustained histologic remission.

Allogenic Fecal Microbiota Transplantation in Patients With Nonalcoholic Fatty Liver Disease Improves Abnormal Small Intestinal Permeability: A Randomized Control Trial.

INTRODUCTION: Nonalcoholic fatty liver disease (NAFLD) is an obesity-related disorder that is rapidly increasing in incidence and is considered the hepatic manifestation of the metabolic syndrome. The gut microbiome plays a role in metabolism and maintaining gut barrier integrity. Studies have found differences in the microbiota between NAFLD and healthy patients and increased intestinal permeability in patients with NAFLD. Fecal microbiota transplantation (FMT) can be used to alter the gut microbiome. It was hypothesized that an FMT from a thin and healthy donor given to patients with NAFLD would improve insulin resistance (IR), hepatic proton density fat fraction (PDFF), and intestinal permeability. METHODS: Twenty-one patients with NAFLD were recruited and randomized in a ratio of 3:1 to either an allogenic (n = 15) or an autologous (n = 6) FMT delivered by using an endoscope to the distal duodenum. IR was calculated by HOMA-IR, hepatic PDFF was measured by MRI, and intestinal permeability was tested using the lactulose:mannitol urine test. Additional markers of metabolic syndrome and the gut microbiota were examined. Patient visits occurred at baseline, 2, 6 weeks, and 6 months post-FMT. RESULTS: There were no significant changes in HOMA-IR or hepatic PDFF in patients who received the allogenic or autologous FMT. Allogenic FMT patients with elevated small intestinal permeability (>0.025 lactulose:mannitol, n = 7) at baseline had a significant reduction 6 weeks after allogenic FMT. DISCUSSION: FMT did not improve IR as measured by HOMA-IR or hepatic PDFF but did have the potential to reduce small intestinal permeability in patients with NAFLD.

Screening and Treatment Outcomes in Adults and Children With Type 1 Diabetes and Asymptomatic Celiac Disease: The CD-DIET Study.

OBJECTIVE: To describe celiac disease (CD) screening rates and glycemic outcomes of a gluten-free diet (GFD) in patients with type 1 diabetes who are asymptomatic for CD. RESEARCH DESIGN AND METHODS: Asymptomatic patients (8-45 years) were screened for CD. Biopsy-confirmed CD participants were randomized to GFD or gluten-containing diet (GCD) to assess changes in HbA1c and continuous glucose monitoring over 12 months. RESULTS: Adults had higher CD-seropositivity rates than children (6.8% [95% CI 4.9-8.2%, N = 1,298] vs. 4.7% [95% CI 3.4-5.9%, N = 1,089], P = 0.035) with lower rates of prior CD screening (6.9% vs. 44.2%, P < 0.0001). Fifty-one participants were randomized to a GFD (N = 27) or GCD (N = 24). No HbA1c differences were seen between the groups (+0.14%, 1.5 mmol/mol; 95% CI -0.79 to 1.08; P = 0.76), although greater postprandial glucose increases (4-h +1.5 mmol/L; 95% CI 0.4-2.7; P = 0.014) emerged with a GFD. CONCLUSIONS: CD is frequently observed in asymptomatic patients with type 1 diabetes, and clinical vigilance is warranted with initiation of a GFD.

Safety of Combination Biologic and Antirejection Therapy Post-Liver Transplantation in Patients With Inflammatory Bowel Disease.

BACKGROUND: Patients with inflammatory bowel disease (IBD) post-liver transplant (LT) may have bowel inflammation requiring biologic therapy. We aimed to evaluate the safety of combination biologic and antirejection therapy in IBD patients after LT from a tertiary center case series and an updated literature review. METHODS: Inflammatory bowel disease patients undergoing LT between 1985 and 2018 and requiring combination biologic and antirejection therapy post-LT were identified from the London Health Sciences Transplant Registry (Ontario, Canada). Safety outcomes were extracted by medical chart review. For an updated literature review, EMBASE, Medline, and CENTRAL were searched to identify studies evaluating the safety of combination biologic and antirejection therapy in IBD patients. RESULTS: In the case series, 19 patients were identified. Most underwent LT for primary sclerosing cholangitis (PSC; 14/19, 74%) treated with anti-integrins (8/19, 42%) or tumor necrosis factor α (TNF) antagonists (6/19, 32%). Infections occurred in 11/19 (58%) patients, most commonly Clostridium difficile (4/19, 21%). Two patients required colectomy, and 1 patient required re-transplantation. In the literature review, 13 case series and 8 case reports reporting outcomes for 122 IBD patients treated with biologic and antirejection therapy post-LT were included. PSC was the indication for LT in 97/122 (80%) patients, and 91/122 (75%) patients were treated with TNF antagonists. Infections occurred in 32/122 (26%) patients, primarily Clostridium difficile (7/122, 6%). CONCLUSIONS: Inflammatory bowel disease patients receiving combination biologic and antirejection therapy post-LT appeared to be at increased risk of Clostridium difficile. Compared with the general liver transplant population in the published literature, there was no increased risk of serious infection.

Equity and Gender Issues Among Members of the Canadian Association of Gastroenterology.

BACKGROUND: Gender equity has historically been a challenge within gastroenterology. AIMS: The Canadian Association of Gastroenterology (CAG) developed a survey to identify issues pertaining to equity and gender faced by its membership and to determine areas of action. METHODS: In 2014, the survey was emailed to all 1155 CAG members, and the data were analyzed using statistical methods. RESULTS: One hundred eleven CAG members responded to the survey. Of those, 52% were male, 75% were between 26 and 45 years of age, and 55% were in their first decade of practice. More males held the status of full professor (21% versus 0%; P=0.022). Male CAG members reported working more hours per week than their female counterparts (58.3 ± 15.4 versus 52.3 ± 11.8, P=0.025). Regarding commitments outside the workplace, 81% of respondents had a spouse/partner, and 52% had children under 18 years of age, both of which did not significantly differ based on gender. Overall, 70% were satisfied or very satisfied with their career path. However, significantly more females felt their age/ethnicity/gender/marital status hindered career advancement (36% versus 14%; P=0.008). Furthermore, more females reported difficulties attaining work-life balance (45% versus 22%; P=0.015). CONCLUSIONS: This survey highlights that gender and equity challenges continue to exist within gastroenterology. The needs assessment highlights that work-life balance, physician well-being, negotiation skills and mentorship are areas of importance to many CAG members.

Crohn's Disease Is Associated with Decreased CYP3A4 and P-Glycoprotein Protein Expression.

Cytochrome P450 (CYP) 3A4 and P-glycoprotein (P-gp) have broad substrate overlap and are involved in the metabolism and transport of nearly 50% of currently prescribed medications. In the intestine, CYP3A4 and P-gp are coexpressed in the enterocytes at the intestinal villous tip and act in a coordinated manner to limit drug and xenobiotic oral bioavailability prior to further metabolism and disposition in the liver. Crohn's disease (CD), a form of inflammatory bowel disease, introduces a transmural intestinal insult that disrupts the intestinal barrier function; it therefore has the potential to affect intestinal drug metabolism and transport. We hypothesized that individuals with CD have reduced intestinal expression of CYP3A4 and P-gp. We obtained intestinal biopsy samples from individuals with and without CD and quantified the expression of CYP3A4 and P-gp. When we carried out Western analysis for protein expression, we observed a significant reduction in ileal (45% decrease) and colonic (78% decrease) CYP3A4 protein expression in subjects with CD compared with those without. Similarly, an 85% reduction in colonic P-gp protein expression was seen in the CD patients. Our data highlight important and novel findings pertaining to CD-associated changes to the intestinal expression of CYP3A4 and P-gp that are of relevance to better predict substrate drug dosing for patients with CD.

Apixaban and Rosuvas--tatin Pharmacokinetics in Nonalcoholic Fatty Liver Disease.

There is little known about the impact of nonalcoholic fatty liver disease (NAFLD) on drug metabolism and transport. We examined the pharmacokinetics of oral apixaban (2.5 mg) and rosuvastatin (5 mg) when administered simultaneously in subjects with magnetic resonance imaging-confirmed NAFLD (N = 22) and healthy control subjects (N = 12). The area under the concentration-time curve to the last sampling time (AUC0-12) values for apixaban were not different between control and NAFLD subjects (671 and 545 ng/ml × hour, respectively; P = 0.15). Similarly, the AUC0-12 values for rosuvastatin did not differ between the control and NAFLD groups (25.4 and 20.1 ng/ml × hour, respectively; P = 0.28). Furthermore, hepatic fibrosis in NAFLD subjects was not associated with differences in apixaban or rosuvastatin pharmacokinetics. Decreased systemic exposures for both apixaban and rosuvastatin were associated with increased body weight (P < 0.001 and P < 0.05, respectively). In multivariable linear regression analyses, only participant weight but not NAFLD, age, or SLCO1B1/ABCG2/CYP3A5 genotypes, was associated with apixaban and rosuvastatin AUC0-12 (P < 0.001 and P = 0.06, respectively). NAFLD does not appear to affect the pharmacokinetics of apixaban or rosuvastatin.

Sitagliptin in patients with non-alcoholic steatohepatitis: A randomized, placebo-controlled trial.

AIM: To evaluate the effect of sitagliptin vs placebo on histologic and non-histologic parameters of non-alcoholic steatohepatitis (NASH). METHODS: Twelve patients with biopsy-proven NASH were randomized to sitagliptin (100 mg daily) (n = 6) or placebo (n = 6) for 24 wk. The primary outcome was improvement in liver fibrosis after 24 wk. Secondary outcomes included evaluation of changes in NAFLD activity score (NAS), individual components of NAS (hepatocyte ballooning, lobular inflammation, and steatosis), glycemic control and insulin resistance [including measurements of glycated hemoglobin (HbA1C) and adipocytokines], lipid profile including free fatty acids, adipose distribution measured using magnetic resonance imaging (MRI), and thrombosis markers (platelet aggregation and plasminogen activator inhibitor 1 levels). We also sought to determine the correlation between changes in hepatic fat fraction (%) [as measured using the Iterative Decomposition of water and fat with Echo Asymmetry and Least-squares estimation (IDEAL) MRI technique] and changes in hepatic steatosis on liver biopsy. RESULTS: Sitagliptin was not significantly better than placebo at reducing liver fibrosis score as measured on liver biopsy (mean difference between sitagliptin and placebo arms, 0.40, P = 0.82). There were no significant improvements evident with the use of sitagliptin vs placebo for the secondary histologic outcomes of NAS total score as well as for the individual components of NAS. Compared to baseline, those patients who received sitagliptin demonstrated improved HbA1C (6.7% ± 0.4% vs 7.9% ± 1.0%, P = 0.02), and trended towards improved adiponectin levels (4.7 ± 3.5 µg/mL vs 3.9 ± 2.7 µg/mL, P = 0.06) and triglyceride levels (1.26 ± 0.43 mmol/L vs 2.80 ± 1.64 mmol/L, P = 0.08). However, when compared with placebo, sitagliptin did not cause a statistically significant improvement in HbA1C (mean difference, -0.7%, P = 0.19) nor triglyceride levels (mean difference -1.10 mmol/L, P = 0.19) but did trend towards improved adiponectin levels only (mean difference, 0.60 µg/mL, P = 0.095). No significant changes in anthropometrics, liver enzymes, other adipocytokines, lipid profile, thrombosis parameters, or adipose distribution were demonstrated. The MRI IDEAL procedure correlated well with steatosis scores obtained on liver biopsy in both groups at baseline and post-treatment, and the Spearman correlation coefficients ranged from r = 0.819 (baseline) to r = 0.878 (post-treatment), P = 0.002. CONCLUSION: Sitagliptin does not improve fibrosis score or NAS after 24 wk of therapy. The MRI IDEAL technique may be useful for non-invasive measurement of hepatic steatosis.

A Fibroblast Growth Factor 21-Pregnane X Receptor Pathway Downregulates Hepatic CYP3A4 in Nonalcoholic Fatty Liver Disease.

Nonalcoholic fatty liver disease (NAFLD) alters drug response. We previously reported that NAFLD is associated with reduced in vivo CYP3A drug-metabolism activity and hepatic CYP3A4 expression in humans as well as mouse and human hepatoma models of the disease. Here, we investigated the role of the lipid- and glucose-modulating hormone fibroblast growth factor 21 (FGF21) in the molecular mechanism regulating CYP3A4 expression in NAFLD. In human subjects, mouse and cellular NAFLD models with lower CYP3A4 expression, circulating FGF21, or hepatic FGF21 mRNA levels were elevated. Administration of recombinant FGF21 or transient hepatic overexpression of FGF21 resulted in reduced liver CYP3A4 luciferase reporter activity in mice and decreased CYP3A4 mRNA expression and activity in cultured Huh7 hepatoma cells. Blocking canonical FGF21 signaling by pharmacological inhibition of MEK1 kinase in Huh7 cells caused de-repression of CYP3A4 mRNA expression with FGF21 treatment. Mice with high-fat diet-induced simple hepatic steatosis and lipid-loaded Huh7 cells had reduced nuclear localization of the pregnane X receptor (PXR), a key transcriptional regulator of CYP3A4 Furthermore, decreased nuclear PXR was observed in mouse liver and Huh7 cells after FGF21 treatment or FGF21 overexpression. Decreased PXR binding to the CYP3A4 proximal promoter was found in FGF21-treated Huh7 cells. An FGF21-PXR signaling pathway may be involved in decreased hepatic CYP3A4 metabolic activity in NAFLD.

Computed Tomography Measurement of Hepatic Steatosis: Prevalence of Hepatic Steatosis in a Canadian Population.

Background/Aims. Nonalcoholic fatty liver disease (NAFLD) is a chronic liver disease that can progress to cirrhosis and hepatocellular carcinoma. This retrospective chart review investigated the incidence of hepatic steatosis in London, Ontario, Canada. Methods. A retrospective chart review was performed on emergency room (ER) patients undergoing nonscheduled computed tomography (CT) imaging over a six-month period in London, Ontario. CT images and reports were examined to determine presence of steatosis. Analyses of the electronic chart for a period of six months following the CT and communication with the patients' family doctors were used to determine if there was follow-up. Waist circumference, subcutaneous fat depth, and abdominal fat volumes were calculated. Results. 48/450 patients meeting inclusion criteria were identified by radiology as having steatosis, with 34/40 (85%) family physicians unaware of the finding. 24.7% (100/405) of patients met standard CT criteria for steatosis, 40 of which were reported by the radiologist. Waist circumference, subcutaneous adipose tissue depth, subcutaneous adipose tissue volume, and visceral adipose tissue volume were significantly associated with steatosis. Conclusions. The hepatic steatosis prevalence we report is the first reported in a Canadian population. Early identification of steatosis will become more important as new pharmacologic therapies arise.