Comprehensive review: antitumor necrosis factor agents in inflammatory bowel disease and factors implicated in treatment response

G Protein-Coupled Estrogen Receptor-Mediated Anti-Inflammatory and Mucosal Healing Activity of a Trimethylpyridinol Analogue in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is characterized by abnormal immune responses, including elevated proinflammatory cytokines, such as tumor necrosis factor-α (TNFα) and interleukin-6 (IL-6) in the gastrointestinal (GI) tract. This study presents the synthesis and anti-inflammatory evaluation of 2,4,5-trimethylpyridin-3-ol analogues, which exhibit dual inhibition of TNFα- and IL-6-induced inflammation. Analysis using in silico methods, including 3D shape-based target identification, modeling, and docking, identified G protein-coupled estrogen receptor 1 (GPER) as the molecular target for the most effective analogue, 6-26, which exhibits remarkable efficacy in ameliorating inflammation and restoring colonic mucosal integrity. This was further validated by surface plasmon resonance (SPR) assay results, which showed direct binding to GPER, and by the results showing that GPER knockdown abolished the inhibitory effects of 6-26 on TNFα and IL-6 actions. Notably, 6-26 displayed no cytotoxicity, unlike G1 and G15, a well-known GPER agonist and an antagonist, respectively, which induced necroptosis independently of GPER. These findings suggest that the GPER-selective compound 6-26 holds promise as a therapeutic candidate for IBD.

Baseline Expression of Immune Gene Modules in Blood is Associated With Primary Response to Anti-TNF Therapy in Crohn's Disease Patients

BACKGROUND AND AIMS

Anti-tumour necrosis factor [anti-TNF] therapy is widely used for the treatment of inflammatory bowel disease, yet many patients are primary non-responders, failing to respond to induction therapy. We aimed to identify blood gene expression differences between primary responders and primary non-responders to anti-TNF monoclonal antibodies [infliximab and adalimumab], and to predict response status from blood gene expression and clinical data.

METHODS

The Personalised Anti-TNF Therapy in Crohn's Disease [PANTS] study is a UK-wide prospective observational cohort study of anti-TNF therapy outcome in anti-TNF-naive Crohn's disease patients [ClinicalTrials.gov identifier: NCT03088449]. Blood gene expression in 324 unique patients was measured by RNA-sequencing at baseline [week 0], and at weeks 14, 30, and 54 after treatment initiation [total sample size = 814].

RESULTS

After adjusting for clinical covariates and estimated blood cell composition, baseline expression of major histocompatibility complex, antigen presentation, myeloid cell enriched receptor, and other innate immune gene modules was significantly higher in anti-TNF responders vs non-responders. Expression changes from baseline to week 14 were generally of consistent direction but greater magnitude [i.e. amplified] in responders, but interferon-related genes were upregulated uniquely in non-responders. Expression differences between responders and non-responders observed at week 14 were maintained at weeks 30 and 54. Prediction of response status from baseline clinical data, cell composition, and module expression was poor.

CONCLUSIONS

Baseline gene module expression was associated with primary response to anti-TNF therapy in PANTS patients. However, these baseline expression differences did not predict response with sufficient sensitivity for clinical use.

FTY720 attenuates acute colitis via colonic T cells reduction and inhibition of M1 macrophages polarization independent of CCR2-mediated monocytes input

Ulcerative colitis (UC) is a complex multifactorial disease, of which the exact etiology is not fully understood. The inappropriate aggressive inflammatory response is closely related to the disease progression of UC. FTY720 is a sphingosine-1-phosphate receptor agonist and acts as a key immunomodulator in inflammation. This study aims to investigate the protective influence of FTY720 on inflammation in the DSS-induced colitis model. In the present study, the C57BL/6 mice and the CCR2-/- mice were exposed to 5% Dextran Sodium Sulfate (DSS) drinking water for 6 days followed by an injection of FTY720 (1 mg/kg/d) or vehicle (PBS) 6 times starting on the next day. The body weight, stool consistency, and occult blood were assessed daily. The inflammatory cytokines level in colon tissues and serum were assessed. Leukocyte subsets of bone marrow (BM), spleen, and colon were analyzed by flow cytometry. Our results demonstrated that FTY720 ameliorated the aberrant immune responses by trapping T cells and inhibiting the polarization of M1 macrophages in colitis mice. The effect of FTY720 on the increased number of colonic macrophages did not dependent on CCR2-mediated monocyte influx, despite most monocytes being reduced after DSS administration in the inflamed colon of CCR2-/- mice. Rather, depletion of CCR2 did not impact the protective influence of FTY720 on colonic injury in acute colitis. All these findings unravel a beneficial function of FTY720 in the inflammatory response to DSS-induced acute colitis, provided further insights into monocyte migration and might provide potential opportunities for UC therapeutic intervention.

Differential Gene Expression of Checkpoint Markers and Cancer Markers in Mouse Models of Spontaneous Chronic Colitis

The presence of checkpoint markers in cancer cells aids in immune escape. The identification of checkpoint markers and early cancer markers is of utmost importance to gain clarity regarding the relationship between colitis and progressive inflammation leading to cancer. Herein, the gene expression levels of checkpoint makers, cancer-related pathways, and cancer genes in colon tissues of mouse models of chronic colitis (Winnie and Winnie-Prolapse mice) using next-generation sequencing are determined. Winnie mice are a result of a Muc2 missense mutation. The identification of such genes and their subsequent expression and role at the protein level would enable novel markers for the early diagnosis of cancer in IBD patients. The differentially expressed genes in the colonic transcriptome were analysed based on the Kyoto Encyclopedia of Genes and Genomes pathway. The expression of several oncogenes is associated with the severity of IBD, with Winnie-Prolapse mice expressing a large number of key genes associated with development of cancer. This research presents a number of new targets to evaluate for the development of biomarkers and therapeutics.

Serum oncostatin M predicts mucosal healing in patients with inflammatory bowel diseases treated with anti-TNF, but not vedolizumab

BACKGROUND

Oncostatin M was recently highlighted as a promising biomarker for therapeutic effectiveness in inflammatory bowel diseases (IBD), with particular regard for infliximab. The primary aim was to evaluate the ability of serum oncostatin M to predict endoscopic response to different drugs in IBD.

METHODS

We selected two different cohorts of patients with IBD, treated with anti-TNF (infliximab and adalimumab) or with vedolizumab. Therapeutic response was evaluated at week 54 in terms of mucosal healing. Serum oncostatin M and C-reactive protein were measured at baseline; fecal calprotectin was measured at baseline and after 14 weeks of treatment. We evaluated the association of these biomarkers with mucosal healing at week 54.

RESULTS

Among 66 patients treated with anti-TNFs and 68 treated with vedolizumab, 35 and 31 attained mucosal healing, respectively. Mucosal healing at 54 weeks was significantly associated with low oncostatin M levels at baseline in the anti-TNF cohort; the diagnostic accuracy of oncostatin M at baseline in predicting mucosal healing was 0.91 (95% CI 0.84 to 0.99) in the anti-TNF cohort and 0.56 (95% CI 0.43 to 0.70, P < 0.001) in the vedolizumab cohort. Mucosal healing was also associated with low fecal calprotectin levels at week 14 in both cohorts.

CONCLUSION

Our study suggests that serum oncostatin M is a drug-specific biomarker, since it could be used to predict therapeutic effectiveness to anti-TNFs but not to vedolizumab. Moreover, these results emphasize the utility of serum oncostatin M measurement in patients treated with anti-TNF.

Retrospective Database Analysis: Dose Escalation and Adherence in Patients Initiating Biologics for Ulcerative Colitis

BACKGROUND

Biologic therapies are often used in patients with ulcerative colitis (UC) who are nonresponsive to conventional treatments. However, nonresponse or loss of response to biologics often occurs, leading to dose escalation, combination therapy, and/or treatment switching. We investigated real-world treatment patterns of biologic therapies among patients with UC in the USA.

METHODS

This study analyzed data from the IBM® MarketScan® Commercial and Medicare Supplemental Databases (medical/pharmacy claims for >250 million patients in the USA) to identify patients with UC initiating a biologic therapy (adalimumab, infliximab, golimumab, or vedolizumab) with 12 months of follow-up post-initiation. Key measures were patient baseline characteristics, dose escalation (average maintenance dose >20% higher than label), adherence (proportion of days covered), and ulcerative colitis-related healthcare costs in the 12 months following biologic therapy initiation.

RESULTS

Of 2,331 patients included in the study (adalimumab [N = 1,291], infliximab [N = 810], golimumab [N = 127], and vedolizumab [N = 103]), 28.1% used concomitant immunosuppressant therapy within 12 months post-initiation. Overall, 23.6% (adalimumab), 34.8% (infliximab), 9.9% (golimumab), and 39.2% (vedolizumab) of patients dose escalated within 12 months. Patients who dose escalated incurred USD 20,106 higher total UC-related healthcare costs over 12 months than those who did not. Adherence (covariate-adjusted proportion of days covered) ranged from 0.63 to 0.73, and 39.3% of patients discontinued within 12 months (median treatment duration = 112 days).

CONCLUSION

Dose escalation was common, and incurred higher costs, in patients with UC initiating biologic therapies. Suboptimal adherence and/or discontinuation within 12 months of initiation occurred frequently, highlighting the challenges in managing these patients.

The transcription factor Cdx2 regulates inflammasome activity through expression of the NLRP3 suppressor TRIM31 to maintain intestinal homeostasis

The intestine-specific transcription factor Cdx2 is essential for intestinal homeostasis and has been implicated in the pathogenesis of disorders including inflammatory bowel disease. However, the mechanism by which Cdx2 influences intestinal disease is not clear. Here, we present evidence supporting a novel Cdx2–TRIM31–NLRP3 (NLR family, pyrin domain containing 3) signaling pathway, which may represent a mechanistic means by which Cdx2 impacts intestinal inflammation. We found that conditional loss of Cdx function resulted in an increase in proinflammatory cytokines, including tumor necrosis factor alpha, interleukin (IL)-1β, and IL-6, in the mouse colon. We further show that TRIM31, which encodes a suppressor of NLRP3 (a central component of the NLRP3 inflammasome complex) is a novel Cdx2 target gene and is attenuated in the colon of Cdx conditional mutants. Consistent with this, we found that attenuation of TRIM31 in Cdx mutant intestine occurs concomitant with elevated levels of NLRP3 and an increase in inflammasome products. We demonstrate that specific inhibition of NLRP3 activity significantly reduced IL-1β and IL-6 levels and extended the life span of Cdx conditional mutants, reflecting the therapeutic potential of targeting NLRP3. Tumor necrosis factor-alpha levels were also induced independent of NLRP3, potentially via elevated activity of the proinflammatory NF-κB signaling pathway in Cdx mutants. Finally, in silico analysis of ulcerative colitis patients revealed attenuation of CDX2 and TRIM31 expression coincident with enhanced expression of proinflammatory cytokines. We conclude that the novel Cdx2–TRIM31–NLRP3 signaling pathway promotes proinflammatory cytokine expression, and its inhibition may have therapeutic potential in human intestinal diseases.

BMI is important in predicting the loss of response in inflammatory bowel disease patients on tumour necrosis factor-α inhibitors

INTRODUCTION

Obesity is an emerging phenomenon among patients with inflammatory bowel disease (IBD). This study aims to evaluate whether the response to tumour necrosis factor-α (TNF-α) inhibitors (infliximab and adalimumab) could be influenced by BMI in IBD.

METHODS

We identified a cohort of 181 IBD patients attending a single-tertiary centre, naive to biologic therapy and stratified them according to their BMI. The primary outcome is the first occurrence of loss of response (LOR).

RESULTS

The median BMI was 26 kg/m2 (15-63 kg/m2). Approximately 68% of patients had LOR on both adalimumab (ADA) (n = 52) and infliximab (IFX) (n = 71). However, 83% on ADA with BMI ≥30 kg/m2 had LOR compared to 61% on IFX with BMI ≥30 kg/m2. For patients on ADA, Cox regression analysis revealed that after accounting for age, sex, disease type, duration of disease, fistulising disease, smoking status, haemoglobin, C-reactive protein, albumin and platelet levels, there were statistically significant associations between BMI (≥30 kg/m2 vs. <30 kg/m2) and LOR [P = 0.010; hazard ratio (HR) 3.2; confidence interval (CI), 1.3-7.6]. However, for patients on IFX, after accounting for the same factors, the only significant factor was the association of lower rate of LOR with higher albumin levels (P = 0.024; HR 0.95; CI, 0.91-0.99). There was an increased accelerated time to LOR for patients on ADA with BMI ≥30 kg/m2 compared to BMI <30 kg/m2 (P = 0.026). However, there was no difference in time to LOR for patients on IFX (P = 0.177).

CONCLUSION

BMI is important in predicting the LOR among IBD patients on TNF-α inhibitors, especially among patients receiving ADA.

The cholinergic anti-inflammatory pathway in humans: State-of-the-art review and future directions

The parasympathetic nervous system modulates inflammation through efferent vagus nerve signaling. Tracey (2002) termed this process as the cholinergic anti-inflammatory pathway (CAP). Interest in the potential practical use of this immune-modulatory process is increasing alongside increasing appreciation for the role of systemic inflammation in the etiology of somatic and psychological disease. A diverse literature exists providing expansive correlational evidence and some preliminary experimental evidence of the CAP in humans. However, so far this literature has not been well integrated and critically evaluated. This review describes the current state-of-the-art of research into vagus nerve driven parasympathetic control of inflammation in humans. Substantial limitations and gaps in the literature are identified, and promising directions for future research are highlighted.

Diabetic Complications: An Update on Pathobiology and Therapeutic Strategies

Despite the advent of novel therapies which manage and control diabetes well, the increased risk of morbidity and mortality in diabetic subjects is associated with the devastating secondary complications it produces. Long-standing diabetes majorly drives cellular and molecular alterations, which eventually damage both small and large blood vessels. The complications are prevalent both in type I and type II diabetic subjects. The microvascular complications include diabetic neuropathy, diabetic nephropathy, diabetic retinopathy, while the macrovascular complications include diabetic heart disease and stroke. The current therapeutic strategy alleviates the complications to some extent but does not cure or prevent them. Also, the recent clinical trial outcomes in this field are disappointing. Success in the drug discovery of diabetic complications may be achieved by a better understanding of the underlying pathophysiology and by recognising the crucial factors contributing to the development and progression of the disease. In this review, we discuss the well-studied cellular mechanisms leading to the development and progression of diabetic complications. In addition, we also highlight the various therapeutic paradigms currently in clinical practice.

Factors associated with time to clinical remission in pediatric luminal Crohn's disease: A retrospective cohort study

Background and Aim

Data on factors influencing time to remission in pediatric Crohn's disease (CD) are very limited in the literature. The aim of this retrospective cohort study was to describe the trends of time to clinical remission over the past decade and to identify factors associated with time to clinical remission in children with luminal CD.

Methods

Patients under 18 years old diagnosed between 2009 and 2019 were included. All data were collected from the patients' medical records. Survival analyses and linear regression models were used to assess the impact of clinical, laboratory, endoscopic, histological, and therapeutic factors on time to clinical remission.

Results

A total of 654 patients were included in the study. There was no change in the time to clinical remission over the decade. Female sex in adolescents (adjusted bêta regression coefficient [aβ] = 31.8 days, P = 0.02), upper digestive tract involvement (aβ = 46.4 days, P = 0.04) perianal disease (aβ = 32.2 days, P = 0.04), presence of active inflammation on biopsies at diagnosis (aβ = 46.7 days, P = 0.01) and oral 5‐aminosalicylates (5‐ASA) exposure (aβ = 56.6 days, P = 0.002) were associated with longer time to clinical remission. Antibiotic exposure (aβ = −29.3 days, P = 0.04), increased eosinophils (aβ = −29.6 days, P = 0.008) and combination of exclusive enteral nutrition with tumor‐necrosis‐factor‐alpha (TNF‐alpha) inhibitors as induction therapy (aβ = −36.8 days, P = 0.04) were associated with shorter time to clinical remission.

Conclusion

In children with newly diagnosed Crohn's disease, time to clinical remission did not shorten during the decade. It was associated with baseline clinical and histological data and treatment strategies. Combination of enteral nutrition and TNF‐alpha inhibitors was associated with faster clinical remission.

Cytosolic Phospholipase A2 Is Required for Fexofenadine's Therapeutic Effects against Inflammatory Bowel Disease in Mice

Inflammatory Bowel Disease (IBD) is an autoimmune condition with complicated pathology and diverse clinical signs. TNFα is believed to play a crucial role in the pathogenesis of IBD. We recently identified fexofenadine, a well-known antagonist of histamine H1 receptor, as a novel inhibitor of TNFα signaling. Additionally, cytosolic phospholipase A2 (cPLA2) was isolated as a binding target of fexofenadine, and fexofenadine-mediated anti-TNF activity relied on cPLA2 in vitro. The objective of this study is to determine whether fexofenadine is therapeutic against chemically-induced murine IBD model and whether cPLA2 and/or histamine H1 receptor is important for fexofenadine's anti-inflammatory activity in vivo by leveraging various genetically modified mice and chemically induced murine IBD models. Both dextran sulfate sodium- and 2, 4, 6-trinitrobenzene sulfonic acid-induced murine IBD models revealed that orally delivered fexofenadine was therapeutic against IBD, evidenced by mitigated clinical symptoms, decreased secretions of the proinflammatory cytokine IL-6 and IL-1β, lowered intestinal inflammation, and reduced p-p65 and p-IĸBα. Intriguingly, Fexofenadine-mediated protective effects against IBD were lost in cPLA2 deficient mice but not in histamine H1 receptor-deficient mice. Collectively, these findings demonstrate the therapeutic effects of over-the-counter drug Fexofenadine in treating DSS-induced IBD murine and provide first in vivo evidence showing that cPLA2 is required for fexofenadine's therapeutic effects in murine IBD model and probably other inflammatory and autoimmune diseases as well.

Inflammatory bowel disease manifestations in spondyloarthritis: considerations for the clinician

INTRODUCTION

Spondyloarthropathies (SpA) are a group of inflammatory arthritis that can involve the spine and/or peripheral joints. Extra-articular manifestations, such as inflammatory bowel disease (IBD), are frequently observed within the clinical manifestations of SpA and are part of the SpA classification criteria. Evidence of IBD is observed in about 6-7% of SpA patients, and a silent, microscopic gut inflammation, could be present in up to 50% of patients. From a pathogenetic point of view, dysregulated microbiome and migration of T lymphocytes and other cells from gut to the joint ('gut-joint' axis) has been recognized, in the context of a common genetic background.

AREAS COVERED

The aim of this paper is to narratively review the recent evidences on the epidemiology, classification, clinical findings, pathogenesis, diagnosis, and treatment of IBD in patients with SpA and to provide advices for both rheumatologist and gastroenterologist in the management of IBD in SpA.

EXPERT OPINION

IBD manifestations in SpA frequently increase the burden of the disease and represent a clinical challenge, especially for the diagnosis, assessment, and treatment of patients affected by those conditions. New treatment strategies targeting both articular and intestinal manifestations are now available and may lead to a better outcome.

Urotensin II levels in patients with inflammatory bowel disease

BACKGROUND

Patients with inflammatory bowel disease (IBD) are associated with increased cardiovascular risk and have increased overall cardiovascular burden. On the other hand, urotensin II (UII) is one of the most potent vascular constrictors with immunomodulatory effect that is connected with a number of different cardiometabolic disorders as well. Furthermore, patients with ulcerative colitis have shown increased expression of urotensin II receptor in comparison to healthy controls. Since the features of IBD includes chronic inflammation and endothelial dysfunction as well, it is plausible to assume that there is connection between increased cardiac risk in IBD and UII.

AIM

To determine serum UII levels in patients with IBD and to compare them to control subjects, as well as investigate possible associations with relevant clinical and biochemical parameters.

METHODS

This cross sectional study consecutively enrolled 50 adult IBD patients (26 with Crohn’s disease and 24 with ulcerative colitis) and 50 age and gender matched controls. Clinical assessment was performed by the same experienced gastroenterologist according to the latest guidelines. Ulcerative Colitis Endoscopic Index of Severity and Simple Endoscopic Score for Crohn’s Disease were used for endoscopic evaluation. Serum levels of UII were determined using the enzyme immunoassay kit for human UII, according to the manufacturer’s instructions.

RESULTS

IBD patients have significantly higher concentrations of UII when compared to control subjects (7.57 ± 1.41 vs 1.98 ± 0.69 ng/mL, P < 0.001), while there were no significant differences between Crohn’s disease and ulcerative colitis patients (7.49 ± 1.42 vs 7.65 ± 1.41 ng/mL, P = 0.689). There was a significant positive correlation between serum UII levels and high sensitivity C reactive peptide levels (r = 0.491, P < 0.001) and a significant negative correlation between serum UII levels and total proteins (r = -0.306, P = 0.032). Additionally, there was a significant positive correlation between serum UII levels with both systolic (r = 0.387, P = 0.005) and diastolic (r = 0.352, P = 0.012) blood pressure. Moreover, serum UII levels had a significant positive correlation with Ulcerative Colitis Endoscopic Index of Severity (r = 0.425, P = 0.048) and Simple Endoscopic Score for Crohn’s Disease (r = 0.466, P = 0.028) scores. Multiple linear regression analysis showed that serum UII levels retained significant association with high sensitivity C reactive peptide (β ± standard error, 0.262 ± 0.076, P < 0.001) and systolic blood pressure (0.040 ± 0.017, P = 0.030).

CONCLUSION

It is possible that UII is involved in the complex pathophysiology of cardiovascular complications in IBD patients, and its purpose should be investigated in further studies.

A random forest model predicts responses to infliximab in Crohn's disease based on clinical and serological parameters

BACKGROUND

Infliximab (IFX) has revolutionised the treatment for Crohn's disease (CD) recently, while a part of patients show no response to it at the end of the induction period. We developed a random forest-based prediction tool to predict the response to IFX in CD patients.

METHODS

This observational study retrospectively enrolled the patients diagnosed with active CD and received IFX treatment at the Gastroenterology Department in Xiangya Hospital of Central South University between January 2017 and December 2019. The baseline data were recorded in the beginning and were used as predictor variables to construct models to forecast the outcome of the response to IFX.

RESULTS

Our cohort identified a total of 174 patients finally with a response rate of 29.3% (51/174). The area under the receiver operating characteristic curve (AUC) for the model, based on the random forest was 0.90 (95%CI: 0.82-0.98), compared to the logistic regression model with AUC of 0.68 (95%CI: 0.52-0.85). The optimal cut-off value of the random forest model was 0.34 with the specificity of 0.94, the sensitivity of 0.81 and the accuracy of 0.85. We demonstrated a strong association of IFX response with the levels of complement C3 (C3), high density lipoprotein, serum albumin, Controlling Nutritional Status (CONUT) score and visceral fat area/subcutaneous fat area ratio (VSR).

CONCLUSION

A novel random forest model using the clinical and serological parameters of baseline data was established to identify CD patients with baseline inflammation to achieve IFX response. This model could be valuable for physicians, patients and insurers, which allows individualised therapy.

Combination Therapy Does Not Improve Rate of Clinical or Endoscopic Remission in Patients with Inflammatory Bowel Diseases Treated With Vedolizumab or Ustekinumab

BACKGROUND & AIMS

Patients with Crohn's disease (CD) or ulcerative colitis (UC) often receive combination therapy with an immunomodulator and tumor necrosis factor antagonists, especially infliximab. However, the benefits of combination therapy with vedolizumab and ustekinumab are unclear.

METHODS

We performed a retrospective study of patients with CD or UC initiating vedolizumab or ustekinumab therapy at Massachusetts General Hospital (USA), Alberta Health Sciences (Canada), or Nancy University Hospital (France) with at least 1 year of follow up. The primary outcome was clinical remission or response at week 14, based on the Harvey Bradshaw index for CD or simple clinical colitis index or partial Mayo score for UC. We separately examined week 30 and week 54 clinical outcomes, endoscopic response, and durability of therapy using multivariable regression models and adjusting for relevant confounders.

RESULTS

Our study included 549 patients (263 with UC, 286 with CD) receiving maintenance therapy with vedolizumab and 363 patients (4 with UC, 359 with CD) receiving maintenance therapy with ustekinumab with 1 year of follow up. The mean disease duration was 13-15 years. One-hundred thirty-one patients receiving vedolizumab (23.9%; 78 receiving thiopurine, 53 receiving methotrexate) and 120 patients receiving ustekinumab (33.1%, 57 receiving thiopurine, 63 receiving methotrexate) were receiving combination therapy. For vedolizumab, there was no difference in clinical response or remission with combination therapy vs monotherapy at week 14 (68.2% vs 74.1%; P = .22), week 30 (74.3% vs 75.6%; P = .78) or week 54 (78.3% vs 72.9%, P = .33). For ustekinumab, there was no difference in clinical response or remission with combination therapy vs monotherapy at week 14 (54.6% vs 65.8%; P = .08), week 30 (71.6% vs 77.4%; P = .33) or week 54 (62.1% vs 67.0%; P = .52). There were similar proportions of patients remaining on treatment or with endoscopic response at 1 year among patients receiving combination or monotherapy with vedolizumab or ustekinumab.

CONCLUSIONS

In patients with CD or UC initiating ustekinumab or vedolizumab therapy, combination therapy with immunomodulators did not increase rates of clinical remission or response, endoscopic remission, or persistence of therapy at 1 year.

Screening for TB in Hospitalised Patients with Inflammatory Bowel Disease before Anti-TNF Therapy: Is QuantiFERON® Gold Testing Useful?

Background—Tumour necrosis factor alpha (TNFα) plays an important role in the pathogenesis of inflammatory bowel disease (IBD) and in immunity to Mycobacterium tuberculosis. Patients should be tested for latent tuberculosis infection using interferon-gamma release assays (IGRA/QF) prior to anti-TNFα therapy. Indeterminate QF results can delay anti-TNFα therapy. We sought to investigate factors associated with indeterminate QF results. Method—Retrospective study of all IGRA tests requested for gastroenterology patients in 2017. We compared inpatients and outpatients and investigated factors potentially associated with QF usefulness (steroid exposure, C-reactive protein (CRP), hypoalbuminaemia, thrombophilia). Results—We included 286 outpatients and 74 inpatients with IBD. Significantly more inpatients had an indeterminate IGRA (52.7% vs. 3.14% in outpatients; p < 0.0001). Laboratory parameters reflecting inflammation (high CRP, low albumin, low haemoglobin and high platelets) were also associated with an indeterminate QF (p < 0.0001). Exposure to steroids was more common in patients with an indeterminate QF (p < 0.0001). A binary logistic regression analysis revealed inpatient status and steroid exposure to be independently predictive of an indeterminate QF (p < 0.0001). Conclusion—There is a high chance of indeterminate QF results in inpatients. QF testing should ideally be performed in the outpatient setting at diagnosis.

Nutritional Interventions Using Functional Foods and Nutraceuticals to Improve Inflammatory Bowel Disease

The gastrointestinal tract, the second largest organ in the body, plays an important role in nutrient and mineral intake through the intestinal barrier. Dysfunction of intestinal permeability and related disorders commonly occur in patients with inflammatory bowel disease (IBD), one of the health problems in the Western societies that are considered to be mainly due to the Western diet. Although the exact etiology of IBD has not been elucidated, environmental and genetic factors may be involved in its pathogenesis. Many synthetic or biological drugs, such as 5-aminosalicylic acid corticosteroids as anti-inflammatory drugs, have been used clinically to treat IBD. However, their long-term use exhibits some adverse health consequences. Therefore, many researchers have devised alternative therapies to overcome this problem. Many studies have revealed that some functional nutrients in nature can relieve gastrointestinal inflammation by controlling proinflammatory cytokines. In this study, we review the ability of functional nutraceuticals such as phytochemicals, fatty acids, and bioactive peptides in improving IBD by regulating its underlying pathogenic mechanisms.

Early serum infliximab trough level and mucosal healing could be predictors for one-year outcome after initiating therapy in Crohn's disease

BACKGROUND AND AIMS

Serum infliximab trough level(S-IFX) and antibody were documented to correlate with clinical response. The aim of this study was to identify the relationship between early S-IFX, early mucosal healing (MH) and one-year outcome in a cohort on maintenance IFX therapy in Crohn's disease (CD).

METHODS

The study group comprised of retrospectively enrolled patients diagnosed for Crohn's disease (n = 108). Patients received scheduled maintenance therapy after response to IFX induction, and had undergone the early S-IFX test and endoscopic examination at week 14. Clinical outcomes were evaluated during maintenance therapy until week 52.

RESULTS

Early S-IFX was 4.78 ± 6.16 ug/ml in all the patients and 19% (21/108) of them developed antibodies, and 52 patients reached early MH. During 52 weeks' follow-up. Twenty-eight percent (30/108) of patients showed loss of response to IFX. Patients who lost response had lower early S-IFX than those who had sustained response (3.01 ± 3.66 vs. 5.47 ± 6.79 ug/ml, p = .02; 48 vs. 23%, p =  .02). At week 52, 73 patients had repeated endoscopy and 42% of them reached MH. Early S-IFX had a predictive value on MH at week 52. When early S-IFX > 2.5 ug/ml, the sensitivity for predicting MH at week 52 was 87%, and the specificity were 61% (AUC = 0.73, p < .01). The combined predictive value of early S-IFX and early MH became stronger. Only 6% (1/18) of those patients who had low early S-IFX and had not reached early MH could reach MH at week 52.

CONCLUSIONS

Early S-IFX and early MH could predict one-year response after initiating IFX therapy in Crohn's disease.

Biological therapy in pediatric age

Biological therapies, especially blocking tumor necrosis factor-α (TNFα) agents have radically changed the therapeutic approach and disease course of pediatric inflammatory bowel disease (IBD). In particular, drugs such as infliximab (IFX) and adalimumab (ADA) have been demonstrated to be effective in inducing and maintaining corticosteroid-free remission in both adult and pediatric patients with Crohns Disease (CD) and Ulcerative colitis (UC). Biosimilar biological (BioS) therapy is increasingly being used in pediatric age even though most knowledge on the safety and efficacy of these agents is based on IFX in adult IBD data. Studies show high rates of clinical response and remission in both IFX naïve patients and in patients switched from originator to BioS with similar risks of adverse events (AEs) as those reported with IFX originator. In the present review indications, efficacy and AEs of biological therapy in pediatric IBD will be discussed, as well as the role of other biological agents such as Golimumab, Vedolizumab and Ustekinumab, the role of BioS biological therapy and utility of therapeutic drug monitoring in clinical practice.

Pharmacokinetics, Pharmacodynamics, and Immunogenicity of Infliximab in Pediatric Inflammatory Bowel Disease: A Systematic Review and Revised Dosing Considerations

OBJECTIVES

Infliximab (IFX), a monoclonal antibody directed against tumor necrosis factor alpha is a potent treatment option for inflammatory bowel disease (IBD). Dosing regimens in children are extrapolated from adult data using a fixed, weight-based dose, which is often not adequate. While clinical trials have focused on safety and efficacy, there is limited data on pharmacokinetic characteristics and immunogenicity of IFX in children. The objective was to provide a systematic overview of current literature on pharmacokinetic and immunogenicity of IFX in children with IBD, to assess the validity of current adult to pediatric dosing extrapolation.

METHODS

A literature search identified publications up to October 2018. Eligibility criteria were study population consisting of children and/or adolescents with IBD, report of IFX trough levels and/or antibodies-to IFX, full text article or abstract, article in English, and original data.

RESULTS

Initial electronic search yielded 2360 potentially relevant articles, with 1831 remaining after removal of duplicates. An additional search yielded another 202 potentially relevant articles. Of the 2033 retrieved articles, 2000 articles were excluded based on title, abstract, or eligibility criteria. Clearance of IFX was increased in young children and children with extensive disease, leading to lower trough levels after extrapolated dosing of 5 mg/kg, antibodies-to IFX emergence, and subsequent reduced efficacy.

CONCLUSIONS

Adult to pediatric weight-based dosing extrapolation is often inadequate. We provide several considerations for optimal dosing of IFX in children and adolescents with IBD.

Potent Inhibitory Effect of BJ-3105, a 6-Alkoxypyridin-3-ol Derivative, on Murine Colitis Is Mediated by Activating AMPK and Inhibiting NOX

Inflammatory bowel disease (IBD) is a chronic relapsing inflammation in the gastrointestinal tract. Biological therapeutics and orally available small molecules like tofacitinib (a JAK inhibitor) have been developed to treat IBD, but half of the patients treated with these drugs fail to achieve sustained remission. In the present study, we compared the therapeutic effects of BJ-3105 (a 6-alkoxypyridin-3-ol derivative) and tofacitinib in IBD. BJ-3105 induced activation of AMP-activated protein kinase (AMPK) in the kinase activity measurement and recovery from cytokine-induced AMPK deactivation in HT-29 human colonic epithelial cells. Similar to tofacitinib and D942 (an AMPK activator), BJ-3105 inhibited IL-6-induced JAK2/STAT3 phosphorylation and TNF-α-stimulated activation of IKK/NF-κB, and consequently, stimulus-induced upregulations of inflammatory cytokines and inflammasome components. In addition, unlike tofacitinib or D942, BJ-3105 inhibited NADPH oxidase (NOX) activation and consequent superoxide production induced by activators (mevalonate and geranylgeranyl pyrophosphate) of the NOX cytosolic component Rac. In mice, oral administration with BJ-3105 ameliorated dextran sulfate sodium (DSS)-induced colitis and azoxymethane/DSS-induced colitis-associated tumor formation (CAT) much more potently than that with tofacitinib. Moreover, BJ-3105 suppressed the more severe form of colitis and CAT formation in mice with AMPK knocked-out in macrophages (AMPKα^fl/fl-Lyz2-Cre mice) with much greater efficacy than tofacitinib. Taken together, our findings suggest BJ-3105, which exerted a much better anti-colitis effect than tofacitinib through AMPK activation and NOX inhibition, is a promising candidate for the treatment of IBD.

Integrating omics for a better understanding of Inflammatory Bowel Disease: a step towards personalized medicine

Background

Inflammatory Bowel Disease (IBD) is a multifactorial chronic disease. Understanding only one aspect of IBD pathogenesis does not reflect the complex nature of IBD nor will it improve its clinical management. Therefore, it is vital to dissect the interactions between the different players in IBD pathogenesis in order to understand the biology of the disease and enhance its clinical outcomes.

Aims

To provide an overview of the available omics data used to assess the potential mechanisms through which various players are contributing to IBD pathogenesis and propose a precision medicine model to fill the current knowledge gap in IBD.

Results

Several studies have reported microbial dysbiosis, immune and metabolic dysregulation in IBD patients, however, this data is not sufficient to create signatures that can differentiate between the disease subtypes or between disease relapse and remission.

Conclusions

We summarized the current knowledge in the application of omics in IBD patients, and we showed that the current knowledge gap in IBD hinders the improvements of clinical decision for treatment as well as the prediction of disease relapse. We propose one way to fill this gap by implementing integrative analysis of various omics datasets generated from one patient at a single time point.

Subsets of mononuclear phagocytes are enriched in the inflamed colons of patients with IBD

BACKGROUND

Myeloid cells, especially mononuclear phagocytes, which include monocytes, macrophages and dendritic cells (DC), play vital roles in innate immunity, and in the initiation and maintenance of adaptive immunity. While T cell-associated activation pathways and cytokines have been identified and evaluated in inflammatory bowel disease (IBD) patients (Neurath, Nat Rev Gastroenterol Hepatol 14:269-78, 1989), the role of mononuclear phagocytes are less understood. Recent reports support the crucial role of DC subsets in the development of acute colitis models (Arimura et al., Mucosal Immunol 10:957-70, 2017), and suggest they may contribute to the pathogenesis of ulcerative colitis (UC) by inducing Th1/Th2/Th17 responses (Matsuno et al., Inflamm Bowel Dis 23:1524-34, 2017).

RESULTS

We performed in silico analysis and evaluated the enrichment of immune cells, with a focus on mononuclear phagocytes in IBD patient colonic biopsies. Samples were from different gut locations, with different levels of disease severity, and with treatment response to current therapies. We observe enrichment of monocytes, M1 macrophages, activated DCs (aDCs) and plasmacytoid dendritic cells (pDCs) in inflamed tissues from various gut locations. This enrichment correlates with disease severity. Additionally, the same mononuclear phagocytes subsets are among the top enriched cell types in both infliximab and vedolizumab treatment non-responder samples. We further investigated the enrichment of selected DC and monocyte subsets based on gene signatures derived from a DC- and monocyte-focused single cell RNA-seq (scRNA-seq) study (Villani et al., Science 356:eaah4573, 2017), and verified enrichment in both inflamed tissues and those with treatment resistance. Moreover, we validated an increased mononuclear phagocyte subset abundance in a Dextran Sulphate Sodium (DSS) induced colitis model in C57Bl/6 mice representative of chronic inflammation.

CONCLUSIONS

We conducted an extensive analysis of immune cell populations in IBD patient colonic samples and identified enriched subsets of monocytes, macrophages and dendritic cells in inflamed tissues. Understanding how they interact with other immune cells and other cells in the colonic microenvironment such as epithelial and stromal cells will help us to delineate disease pathogenesis.

Evaluation of cytokine levels as putative biomarkers to predict the pharmacological response to biologic therapy in inflammatory bowel diseases

Cytokines play a central role in the pathogenesis of inflammatory bowel diseases. For this reason, the vast majority of biological therapies are aimed to block pro-inflammatory cytokines or their receptors. Although these drugs have modified the course of the disease due to their efficacy, a high rate of non-response or loss of response over time is still an important issue for clinicians. In this perspective, many studies have been conducted in recent years to individuate a reliable biomarker of therapeutic response. In this review, we discuss the role of cytokines involved in the pathogenesis and in the therapy of inflammatory bowel diseases, and their putative use as pharmacological biomarkers of therapy responsiveness.

A hydroxyethyl derivative of chrysin exhibits anti-inflammatory activity in dendritic cells and protective effects against dextran sodium salt-induced colitis in mice

Inflammatory bowel disease (IBD) is a chronic disease that occurs in the intestinal tract. Phyto-ingredients have been evaluated for their ability to protect against IBD because of their anti-inflammatory activities. In our previous study, we identified a novel derivative of chrysin (HE-chrysin) using irradiation technology, which exhibited stronger anti-cancer activity in human colorectal cancer cells than the original chrysin. Here, to determine whether HE-chrysin is a new therapeutic candidate for IBD, we investigated the anti-inflammatory effects of HE-chrysin on bone marrow-derived dendritic cells (BMDCs) and dextran sodium salt (DSS)-induced colitis in mice. HE-chrysin more effectively inhibited BMDC maturation compared to chrysin, as demonstrated by the decreased levels of pro-inflammatory cytokines, surface molecules, antigen-presenting ability, and T cell proliferation/activation in lipopolysaccharide-stimulated BMDCs. These anti-inflammatory effects of HE-chrysin were regulated by mitogen-activated protein kinases and nuclear factor-κB. Furthermore, oral administration of HE-chrysin attenuated DSS-induced colitis symptoms and clinical signs in the mouse model. The protective effects of HE-chrysin treatment against colitis were mediated by decreasing Th1- and Th17-type cytokine levels. These results indicate that HE-chrysin is attractive candidate for IBD therapy.

Phosphatidylinositol 3-kinase p110δ drives intestinal fibrosis in SHIP deficiency

Crohn's disease is an immune-mediated disease characterized by inflammation along the gastrointestinal tract. Fibrosis requiring surgery occurs in one-third of people with Crohn's disease but there are no treatments for intestinal fibrosis. Mice deficient in the SH2 domain-containing inositolpolyphosphate 5'-phosphatase (SHIP), a negative regulator of phosphatidylinositol 3-kinase (PI3K) develop spontaneous Crohn's disease-like intestinal inflammation and arginase I (argI)-dependent fibrosis. ArgI is up-regulated in SHIP deficiency by PI3Kp110δ activity. Thus, we hypothesized that SHIP-deficient mice develop fibrosis due to increased PI3Kp110δ activity. In SHIP-deficient mice, genetic ablation or pharmacological inhibition of PI3Kp110δ activity reduced intestinal fibrosis, including muscle thickening, accumulation of vimentin⁺ mesenchymal cells, and collagen deposition. PI3Kp110δ deficiency or inhibition also reduced ileal inflammation in SHIP-deficient mice suggesting that PI3Kp110δ may contribute to inflammation. Targeting PI3Kp110δ activity may be an effective strategy to reduce intestinal fibrosis, and may be particularly effective in the subset of people with Crohn's disease, who have low SHIP activity.

Fasting-Mimicking Diet Modulates Microbiota and Promotes Intestinal Regeneration to Reduce Inflammatory Bowel Disease Pathology

Dietary interventions are potentially effective therapies for inflammatory bowel diseases (IBDs). We tested the effect of 4-day fasting-mimicking diet (FMD) cycles on a chronic dextran sodium sulfate (DSS)-induced murine model resulting in symptoms and pathology associated with IBD. These FMD cycles reduced intestinal inflammation, increased stem cell number, stimulated protective gut microbiota, and reversed intestinal pathology caused by DSS, whereas water-only fasting increased regenerative and reduced inflammatory markers without reversing pathology. Transplants of Lactobacillus or fecal microbiota from DSS- and FMD-treated mice reversed DSS-induced colon shortening, reduced inflammation, and increased colonic stem cells. In a clinical trial, three FMD cycles reduced markers associated with systemic inflammation. The effect of FMD cycles on microbiota composition, immune cell profile, intestinal stem cell levels and the reversal of pathology associated with IBD in mice, and the anti-inflammatory effects demonstrated in a clinical trial show promise for FMD cycles to ameliorate IBD-associated inflammation in humans.

Cellular and Molecular Therapeutic Targets in Inflammatory Bowel Disease-Focusing on Intestinal Barrier Function

The human gut relies on several cellular and molecular mechanisms to allow for an intact and dynamical intestinal barrier. Normally, only small amounts of luminal content pass the mucosa, however, if the control is broken it can lead to enhanced passage, which might damage the mucosa, leading to pathological conditions, such as inflammatory bowel disease (IBD). It is well established that genetic, environmental, and immunological factors all contribute in the pathogenesis of IBD, and a disturbed intestinal barrier function has become a hallmark of the disease. Genetical studies support the involvement of intestinal barrier as several susceptibility genes for IBD encode proteins with key functions in gut barrier and homeostasis. IBD patients are associated with loss in bacterial diversity and shifts in the microbiota, with a possible link to local inflammation. Furthermore, alterations of immune cells and several neuro-immune signaling pathways in the lamina propria have been demonstrated. An inappropriate immune activation might lead to mucosal inflammation, with elevated secretion of pro-inflammatory cytokines that can affect the epithelium and promote a leakier barrier. This review will focus on the main cells and molecular mechanisms in IBD and how these can be targeted in order to improve intestinal barrier function and reduce inflammation.

Alginate/chitosan microcapsules for in-situ delivery of the protein, interleukin-1 receptor antagonist (IL-1Ra), for the treatment of dextran sulfate sodium (DSS)-induced colitis in a mouse model

Targeted delivery of bioactive compounds such as proteins to the colon has numerous advantages for the therapeutic treatment of inflammatory bowel disease. The present study sought to fabricate alginate/chitosan microcapsules containing IL-1Ra (Alg/Chi/IL-1Ra MC) via a single-step electrospraying method. Two important factors of efficacy were measured-the pH-responsiveness of the microcapsule and the in-vitro drug release profile. The DSS-induced colitis mouse model was used to evaluate the therapeutic effect of the Alg/Chi/IL-1Ra microcapsules, with results showing the protective effect of the Alg/Chi microcapsules for the passage of IL-1Ra through the harsh environment of the upper gastrointestinal tract. This effect was owing to the pH-sensitive response of the microcapsule, which allowed the targeted release of IL-1Ra in the colon. DAI evaluation, colon length, colon tissue morphology, histologic damage scores and relative protein concentrations (MPO, TNF-α and IL-1β) demonstrated that the Alg/Chi/IL-1Ra microcapsules alleviated DSS-induced colitis in mice. The present study thus demonstrates a practical means of oral delivery of proteins, in-situ colon release, and a promising application of IL-1Ra in the treatment of autoimmune and inflammatory diseases.

Loss of RHBDF2 results in an early-onset spontaneous murine colitis

Inflammatory bowel disease (IBD) is a heterogeneous group of inflammation-mediated pathologies that include Crohn's disease and ulcerative colitis and primarily affects the colon and small intestine. Previous studies have shown that a disintegrin and metalloprotease (ADAM) 17, a membrane-bound sheddase, capable of cleaving the proinflammatory cytokine TNF and epidermal growth factor receptor ligands, plays a critical role in maintaining gut homeostasis and modulating intestinal inflammation during IBD. Rhomboid 5 homolog 2 (RHBDF2), a catalytically inactive member of the rhomboid family of intramembrane serine proteases, was recently identified as a crucial regulator of ADAM17. Here, we assessed the role of RHBDF2 in the development of colitis in the context of IL10 deficiency. Il10^-/- /Rhbdf2^-/- mice developed spontaneous colitis and experienced severe weight loss starting at 8 wk of age, without the need for exogenous triggers. Severity of disease pathology in Il10^-/- /Rhbdf2^-/- mice correlated with a dysbiotic gut microbiota and elevated Th1-associated immune responses with increased interferon gamma and IL2 production. In addition, Il10^-/- /Rhbdf2^-/- mice failed to maintain their epithelial cell homeostasis, although the intestinal epithelial barrier of Rhbdf2^-/- mice is intact and loss of Rhbdf2 did not significantly exacerbate sensitivity to dextran sulfate sodium-induced colitis, suggesting differences in the underlying disease pathway of intestinal inflammation in this model. Taken together, our results demonstrate a critical regulatory role for RHBDF2 in the maintenance of the unique homeostasis between intestinal microbiota and host immune responses in the gut that is dysregulated during the pathogenesis of IBD.

Use of Biosimilars in Pediatric Inflammatory Bowel Disease: An Updated Position Statement of the Pediatric IBD Porto Group of ESPGHAN

Biologic therapies have changed the outcome of both adult and pediatric patients with Inflammatory Bowel Disease (IBD). In September 2013, the first biosimilar of infliximab was introduced into the pharmaceutical market. In 2015, a first position paper on the use of biosimilars in pediatric IBD was published by the ESPGHAN IBD Porto group. Since then, more data have accumulated for both adults and children demonstrating biosimilars are an effective and safe alternative to the originator. In this updated position statement, we summarize current evidence and provide joint consensus statements regarding the recommended practice of biosimilar use in children with IBD.

Should we use vedolizumab as mono or combo therapy in ulcerative colitis?

Randomized controlled trials comparing the efficacy of vedolizumab monotherapy with combination therapy of vedolizumab and an immunomodulator in patients with ulcerative colitis (UC) are lacking. Emerging pharmacokinetic data indicate that vedolizumab concentrations correlate with clinical outcomes, although the correlation may be less strong for vedolizumab compared with an anti-TNF agents. Associations between concomitant use of immunomodulators and decreased immunogenicity of vedolizumab have been reported, but this does not appear to translate into enhanced therapeutic effect of combination therapy, at least not based on present data. However, data are sparse and often based on post-hoc analyses. Future comparative effectiveness studies of patients with UC, naïve to vedolizumab as well as immunomodulators, are needed. This might be of specific relevance for subgroups of UC patients, such as young men and the elderly, in whom combination versus monotherapy therapy may have a different risk-benefit ratio, given the risk of malignancy associated with immunomodulators.

Clinical effectiveness and cost-effectiveness of use of therapeutic monitoring of tumour necrosis factor alpha (TNF-α) inhibitors [LISA-TRACKER® enzyme-linked immunosorbent assay (ELISA) kits, TNF-α-Blocker ELISA kits and Promonitor® ELISA kits] versus standard care in patients with Crohn's disease: systematic reviews and economic modelling

BACKGROUND AND OBJECTIVES

Systematic reviews and economic modelling of clinical effectiveness and cost-effectiveness of therapeutic monitoring of tumour necrosis factor alpha (TNF-α) inhibitors [using LISA-TRACKER^® enzyme-linked immunosorbent assay (ELISA) kits (Theradiag, Marne La Vallee, France, or Alpha Laboratories, Heriot, UK), TNF-α-Blocker ELISA kits (Immundiagnostik AG, Bensheim, Germany) and Promonitor^® ELISA kits (Proteomika, Progenika Biopharma, Bizkaia, Spain)] versus standard care for Crohn's disease (CD).

METHODS

Multiple electronic databases were searched from inception to December 2014 in order to identify primary studies and meta-analyses.

POPULATION

Patients with moderate to severe active CD treated with infliximab (IFX) (Remicade^®, Merck Sharp & Dohme Ltd, Kenilworth, NJ, USA) or adalimumab (ADA) (Humira^®, AbbVie Inc., North Chicago, IL, USA).

INTERVENTION

Monitoring of serum anti-TNF-α (IFX or ADA) and/or of anti-drug antibody levels using test assays with a test-treatment algorithm.

COMPARATOR

Standard care.

OUTCOMES

Any patient-related outcome, test agreement and cost-effectiveness estimates. The quality assessments used recognised checklists (Quality Assessment of Diagnostic Accuracy Studies-2, Cochrane, Philips and Consolidated Health Economic Evaluation Reporting Standards). Evidence was synthesised using narrative review and meta-analysis. A Markov model was built in TreeAge Pro 2013 (TreeAge Software, Inc., Williamstown, MA, USA). The model had a 4-week cycle and a 10-year time horizon, adopted a NHS and Personal Social Services perspective and used a linked evidence approach. Costs were adjusted to 2013/14 prices and discounted at 3.5%.

RESULTS

We included 68 out of 2434 and 4 out of 2466 studies for the clinical effectiveness and cost-effectiveness reviews, respectively. Twenty-three studies comparing test methods were identified. Evidence on test concordance was sparse and contradictory, offering scant data for a linked evidence approach. Three studies [two randomised controlled trials (RCTs) and one retrospective observational study] investigated outcomes following implementation of a test algorithm. None used the specified commercial ELISA immunoassay test kits. Neither of the two RCTs demonstrated clinical benefit of a test-treatment regimen. A meta-analysis of 31 studies to estimate test accuracy for predicting clinical status indicated that 20-30% of test results are likely to be inaccurate. The four cost-effectiveness studies suggested that testing results in small cost reductions. In the economic analysis the base-case analysis showed that standard practice (no testing/therapeutic monitoring with the intervention tests) was more costly and more effective than testing for IFX. Sensitivity and scenario analyses gave similar results. The probabilistic sensitivity analysis indicated a 92% likelihood that the 'no-testing' strategy was cost-effective at a willingness to pay of £20,000 per quality-adjusted life-year.

STRENGTHS AND LIMITATIONS

Rigorous systematic reviews were undertaken; however, the underlying evidence base was poor or lacking. There was uncertainty about a linked evidence approach and a lack of gold standard for assay comparison. The only comparative evidence available for economic evaluation was for assays other than the intervention assays.

CONCLUSIONS

Our finding that testing is not cost-effective for IFX should be viewed cautiously in view of the limited evidence. Clinicians should be mindful of variation in performance of different assays and of the absence of standardised approaches to patient assessment and treatment algorithms.

FUTURE WORK RECOMMENDATIONS

There is substantial variation in the underlying treatment pathways and uncertainty in the relative effectiveness of assay- and test-based treatment algorithms, which requires further investigation. There is very little research evidence on ADA or on drug monitoring in children with CD, and conclusions on cost-effectiveness could not be reached for these.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42014015278.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Anti-TNFα Treatment in Children and Adolescents With Combined Inflammatory Bowel Disease and Autoimmune Liver Disease

OBJECTIVES

Inflammatory bowel disease (IBD) and autoimmune liver disease (AILD) are closely associated, the former often dictating progression of the latter. Antibodies to tumor necrosis factor alpha (anti-TNFα) are effective in the management of IBD, but may cause liver injury.

METHODS

Retrospective review of medical records of patients with juvenile AILD who received anti-TNFα for IBD to evaluate the safety and efficacy of anti-TNFα.

RESULTS

Eleven patients (6 boys), ages 9 to 15 years (median 13 years) were identified. Ten had ulcerative colitis and 1 Crohn disease; 2 had autoimmune hepatitis type 1 and 9 autoimmune hepatitis-sclerosing cholangitis variant. All patients were started on infliximab (IFX, 5 mg/kg) and 2 required dose increase (10 mg/kg); 3 of 11 switched to adalimumab due to allergic reaction or nonresponse. Three received adalimumab after losing response or developing antibodies to IFX. Liver function tests (LFTs) improved in 5, 1 continued to have stably abnormal LFTs and 2 maintained normal LFTs. Patients on adalimumab showed stable or improved liver function compared to pretreatment status. Six of 8 treated with a full course of IFX maintained clinical remission of IBD for 6 months to 2.5 years; of the 6 patients treated with adalimumab, 1 sustained IBD clinical remission for 24 months, 2 achieved remission only after tacrolimus addition and 3 did not respond.

CONCLUSIONS

IBD in patients with AILD can be aggressive, requiring escalation to anti-TNFα or switching to other biologics. In this series, anti-TNFα did not impair liver function and improved gut disease in most of the patients, indicating that it can be beneficial and safe.

Indicators of suboptimal tumor necrosis factor antagonist therapy in inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is refractory to treatment in one-half of patients.

AIMS

To evaluate the occurrence of suboptimal therapy among patients with IBD treated with tumor necrosis factor antagonists (anti-TNFs).

METHODS

A multinational chart review in Europe and Canada was conducted among IBD patients diagnosed with ulcerative colitis (UC) or Crohn's disease (CD) who initiated anti-TNF therapy between 2009 and 2013. The primary endpoint was the cumulative incidence of suboptimal therapy during a two-year follow-up period, defined by the presence of the following indicators: dose escalation, discontinuation, switching, non-biologic therapy escalation, or surgery.

RESULTS

The study included 1195 anti-TNF initiators (538 UC and 657 CD). The majority of patients (64% of UC and 58% of CD) had at least one indicator of suboptimal therapy. The median time to suboptimal therapy indicator was 12.5 and 17.5 months for UC and CD patients, respectively. Among the 111 UC and 174 CD anti-TNF switchers, 51% and 56% had an indicator of suboptimal therapy, respectively. The median time to suboptimal therapy indicator with the second anti-TNF was 14.3 and 13.0 months for UC and CD patients, respectively.

CONCLUSION

The majority of IBD patients showed suboptimal therapy with current anti-TNFs.

The Innate and Adaptive Immune System as Targets for Biologic Therapies in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is an immune-mediated inflammatory condition causing inflammation of gastrointestinal and systemic cells, with an increasing prevalence worldwide. Many factors are known to trigger and maintain inflammation in IBD including the innate and adaptive immune systems, genetics, the gastrointestinal microbiome and several environmental factors. Our knowledge of the involvement of the immune system in the pathophysiology of IBD has advanced rapidly over the last two decades, leading to the development of several immune-targeted treatments with a biological source, known as biologic agents. The initial focus of these agents was directed against the pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) leading to dramatic changes in the disease course for a proportion of patients with IBD. However, more recently, it has been shown that a significant proportion of patients do not respond to anti-TNF-α directed therapies, leading a shift to other inflammatory pathways and targets, including those of both the innate and adaptive immune systems, and targets linking both systems including anti-leukocyte trafficking agents-integrins and adhesion molecules. This review briefly describes the molecular basis of immune based gastrointestinal inflammation in IBD, and then describes how several current and future biologic agents work to manipulate these pathways, and their clinical success to date.

IMPORTANCE OF MEASURING LEVELS OF INFLIXIMAB IN PATIENTS TREATING INFLAMMATORY BOWEL DISEASE IN A BRAZILIAN COHORT

BACKGROUND

Crohn's disease and ulcerative colitis are chronic inflammatory bowel diseases. In such pathologies, there is an increased production of alpha tumor necrosis factor (TNF-α). Patients, in whom the conventional immunosuppressant treatment fails, require the use of immunobiological therapy, such as anti-TNF-α, a monoclonal antibody. Infliximab is an anti-TNF-α drug, a chimerical immunoglobulin, with a murine component, which is responsible for the generation of immunogenicity against the drug and formation of anti-TNF-α antibodies. The presence of anti-drug antibodies may be responsible for adverse events and reduction of the drug's effectiveness. Patients with inflammatory bowel diseases undergoing therapy with biological medication, such as infliximab, can relapse overtime and this may not be translated into clinical symptoms. Thus, there is a need for a method to evaluate the efficacy of the drug, through the measurement of serum infliximab levels, as well as antibodies research.

OBJECTIVE

This study aimed to measure serum infliximab levels and anti-infliximab antibodies in patients with inflammatory bowel diseases post-induction phase and during maintenance therapy, and describe the therapeutic modifications that took place based on the serum levels results.

METHODS

It was a retrospective study, that included forty-five patients, with a total of 63 samples of infliximab measurement.

RESULTS

Twenty-one patients had an adequate infliximab serum level, 31 had subtherapeutic levels and 11 had supratherapeutic levels. Seven patients had their medication suspended due to therapeutic failure or high levels of antibodies to infliximab.

CONCLUSION

In conclusion, only a third of the patients had adequate infliximab levels and 36% presented with subtherapeutic levels at the end of the induction phase. Therapy optimization occurred based in about 46% of the samples results, demonstrating the importance of having this tool to help the clinical handling of patients with inflammatory bowel diseases ongoing biologic therapy.

Incidence, Prevention and Management of Anti-Drug Antibodies Against Therapeutic Antibodies in Inflammatory Bowel Disease: A Practical Overview

The introduction of biologic therapy has revolutionized the treatment of inflammatory bowel disease (IBD). However, like all therapeutic proteins, monoclonal antibodies have immunogenic potential which is influenced by multiple drug- and patient-related factors. The reported incidence of anti-drug antibodies (ADAs) towards biologic drugs in IBD varies greatly in the literature and depends not only on differences in sensitization but also on the assay methodology and the timepoint of measurement. Sensitization with formation of ADAs is associated with an increased risk of infusion reactions, accelerated drug clearance, and a loss of response (LOR) to drug. Recently, a greater understanding of the pharmacokinetics of therapeutic antibodies has led to the development of new strategies to reduce immunogenicity and more efficient use of these drugs. These preventive strategies include regular scheduled dosing with maintenance of stable therapeutic trough drug concentrations, and co-administration of an immunosuppressive. Sub-therapeutic drug concentrations with low levels of ADAs can generally be overcome with dose escalation, whereas the presence of high concentrations of ADAs requires a switch to another therapeutic agent.

An Overview of the Mechanism of Action of the Monoclonal Antibody Vedolizumab

Vedolizumab is a novel therapeutic monoclonal antibody recently approved for the treatment of moderately to severely active ulcerative colitis and Crohn's disease in adults who have failed at least one conventional therapy. An integrin antagonist, vedolizumab binds to the α₄β₇ integrin which is expressed specifically by a subset of gastrointestinal-homing T lymphocytes. The binding of α₄β₇ integrin to mucosal addressin cell adhesion molecule-1 expressed on the surface of mucosal endothelial cells is a crucial component of the gut-selective homing mechanism for lymphocytes.In contrast, other monoclonal antibodies approved for the treatment of inflammatory bowel diseases, such as tumour necrosis factor α antagonists and the integrin antagonist natalizumab, act systemically or on multiple targets to reduce inflammation.The unique gut selectivity of vedolizumab may contribute to the favourable benefit-risk profile observed in vedolizumab clinical trials. In this review, we summarise data from the preclinical development of vedolizumab and describe the current understanding of the mechanism of action as it relates to other biological therapies for inflammatory bowel disease.

The immunogenicity of biosimilar infliximab: can we extrapolate the data across indications?

Biopharmaceuticals or 'biologics' have revolutionized the treatment of many diseases. However, some patients generate an immune response to such drugs, potentially limiting clinical efficacy and safety. Infliximab (Remicade(®)) is a monoclonal antibody used to treat several immune-mediated inflammatory disorders. A biosimilar of infliximab, CT-P13 (Remsima(®), Inflectra(®)), has recently been approved in Europe for all indications in which infliximab is approved. Approval of CT-P13 was based in part on extrapolation of clinical trial data from two indications (rheumatoid arthritis and ankylosing spondylitis) to all other indications, including inflammatory bowel disease. This review discusses the validity of extrapolating immunogenicity data across indications - a process adopted by the EMA as part of their biosimilar approval process - with a focus on CT-P13.

Integrin CD11b attenuates colitis by strengthening Src-Akt pathway to polarize anti-inflammatory IL-10 expression

Interleukin-10 (IL-10) plays a central role in regulation of intestinal mucosal homeostasis and prevention of inflammatory bowel disease (IBD). We previously reported that CD11b(hi) regulatory dendritic cells (DCs) can produce more IL-10, and CD11b can negatively regulate Toll-like receptors (TLRs)-induced inflammatory responses in macrophages. However whether CD11b and its signaling can control autoimmunity via IL-10 production remains unclear. Here we found that CD11b deficient (Itgam(-/-)) mice were more susceptible to dextran sulfate sodium (DSS)-induced colitis, with more tumor necrosis factor α (TNF-α) while less IL-10 production. CD11b inhibited nuclear factor-kappa B (NF-κB) while promoted activator protein 1 (AP-1) activation through activating sarcoma oncogene (Src), leading to decreased TNF-α while increased IL-10 production. Src interacted with and promoted c-casitas B lineage lymphoma proto-oncogene (c-Cbl)-mediated degradation of the inhibitory subunit p85 of phosphatidylinositol 3-kinase (PI3K). Importantly, Src inhibitor dasatinib aggravated DSS-induced colitis by decreasing IL-10 while increasing TNF-α in vivo. Therefore, CD11b promotes IL-10 production by activating Src-Akt signal pathway. An axis of CD11b-Src pathway is important in balancing homeostasis of TLR-induced pro-inflammatory and anti-inflammatory responses.

Adalimumab and Infliximab in Crohn's disease - real life data from a national retrospective cohort study

AIM

to compare the efficacy and safety of Adalimumab(ADA) and Infliximab(IFX), in a large Romanian population and to identify predictors of response. Methods We performed a national retrospective cohort study including 265 patients (136 ADA, 129 IFX) between 2008-2014. Binary logistic regression was performed with the statistical program Minitab.

RESULTS

Patients were half women, with a median age of 36, a median disease duration of 2.5 years, 80% received Azathioprine. Mean therapy duration was 20 months in ADA group and 36 months in IFX group. Complete response to Adalimumab respectively Infliximab was recorded in 77%vs.65%, secondary loss of response in 18%vs.28%, statistically comparable. We failed to identify predictors of response. In 79.2%of patients with secondary loss of response to ADA, the dose was escalated, 12.5% were switched to Infliximab. In 70%of patients that lost response to IFX, the dose was increased, 30% were switched to Adalimumab.

CONCLUSIONS

Adalimumab and Infliximab have similar efficacy, with a complete response rate of~70%. In case of secondary loss of response to IFX, the best solution is to switch to ADA, with 83% response rate, while in case of secondary loss of response to ADA, increasing the dose leads to 84 % response rate.

Advances in Therapeutic Drug Monitoring of Biologic Therapies in Inflammatory Bowel Disease: 2015 in Review

OPINION STATEMENT

Monoclonal antibody therapy directed against tumor necrosis factor-alpha (anti-TNFs) has revolutionized the care of patients with Crohn's disease and ulcerative colitis. These large proteins are potentially immunogenic. Early clinical trials demonstrated an association with both serum concentrations of these agents as well as the presence of antidrug antibodies generated by the host with loss of response. More recent research has provided further evidence to confirm the impact of low drug trough concentrations and antidrug antibodies on subsequent clinical course in CD and UC. Given these clinical implications, treatment algorithms have been developed to aid clinicians in interpreting trough drug levels and antibody concentrations in those with confirmed active disease. Several studies have demonstrated the utility of these approaches. Furthermore, there are growing data supporting the use of therapeutic drug monitoring in a prospective fashion in those patients who are clinically stable on anti-TNF therapies to ensure they are receiving appropriate dosing and have not yet developed antibodies. In addition, for those who have developed low-level antibodies, increasing the dose of an anti-TNF or adding an immunomodulator may help to overcome this immunologic response. Further research is required to assess these proposed strategies, as well as to determine the role of trough drug level assessment and antibody testing for new anti-TNFs and biologic medication with alternative mechanisms of action.

The Intersection of TNF, IBD and the Microbiome

Inflammatory bowel disease (IBD), comprised of Crohn's disease and ulcerative colitis, is a chronic inflammatory condition of multifactorial etiology and risk factors. Currently, one of the most effective treatments for IBD is the use of Tumor Necrosis Factor (TNF) functional inhibitor drugs, however, this treatment can cause adverse reactions and has a relatively large percentage of incomplete or non-responders. This lack of response may be related to differences in patients' gut microbiomes prior to and after disease initiation or treatment. Recent observations in our lab using a rodent model of IBD support the theory that TNF drives acute colitis, but also that the microbiome differs in association with TNF production and colitis severity. Studies such as this and others provide new insights into host-microbiome interactions associated with colitis that can lead to new therapies to prevent or treat the disease.

Activity of SHIP, Which Prevents Expression of Interleukin 1β, Is Reduced in Patients With Crohn's Disease

BACKGROUND & AIMS

Crohn's disease (CD) is associated with a dysregulated immune response to commensal micro-organisms in the intestine. Mice deficient in inositol polyphosphate 5'-phosphatase D (INPP5D, also known as SHIP) develop intestinal inflammation resembling that of patients with CD. SHIP is a negative regulator of PI3Kp110α activity. We investigated mechanisms of intestinal inflammation in Inpp5d(-/-) mice (SHIP-null mice), and SHIP levels and activity in intestinal tissues of subjects with CD.

METHODS

We collected intestines from SHIP-null mice, as well as Inpp5d(+/+) mice (controls), and measured levels of cytokines of the interleukin 1 (IL1) family (IL1α, IL1β, IL1ra, and IL6) by enzyme-linked immunosorbent assay. Macrophages were isolated from lamina propria cells of mice, IL1β production was measured, and mechanisms of increased IL1β production were investigated. Macrophages were incubated with pan-phosphatidylinositol 3-kinase inhibitors or PI3Kp110α-specific inhibitors. Some mice were given an antagonist of the IL1 receptor; macrophages were depleted from ilea of mice using clodronate-containing liposomes. We obtained ileal biopsies from sites of inflammation and peripheral blood mononuclear cells (PBMCs) from treatment-naïve subjects with CD or without CD (controls), and measured SHIP levels and activity. PBMCs were incubated with lipopolysaccharide and adenosine triphosphate, and levels of IL1β production were measured.

RESULTS

Inflamed intestinal tissues and intestinal macrophages from SHIP-null mice produced higher levels of IL1B and IL18 than intestinal tissues from control mice. We found PI3Kp110α to be required for macrophage transcription of Il1b. Macrophage depletion or injection of an IL1 receptor antagonist reduced ileal inflammation in SHIP-null mice. Inflamed ileal tissues and PBMCs from patients with CD had lower levels of SHIP protein than controls (P < .0001 and P < .0002, respectively). There was an inverse correlation between levels of SHIP activity in PBMCs and induction of IL1β production by lipopolysaccharide and adenosine triphosphate (R(2) = .88).

CONCLUSIONS

Macrophages from SHIP-deficient mice have increased PI3Kp110α-mediated transcription of Il1b, which contributes to spontaneous ileal inflammation. SHIP levels and activity are lower in intestinal tissues and peripheral blood samples from patients with CD than controls. There is an inverse correlation between SHIP activity and induction of IL1β production by lipopolysaccharide and adenosine triphosphate in PBMCs. Strategies to reduce IL1B might be developed to treat patients with CD found to have low SHIP activity.

The Role of Therapeutic Drug Monitoring of Anti-Tumor Necrosis Factor Alpha Agents in Children and Adolescents with Inflammatory Bowel Disease

BACKGROUND

Anti-tumor necrosis factor alpha (TNFα) therapy is effective in pediatric patients with inflammatory bowel disease (IBD) but associated with a risk of developing anti-drug antibodies (ADA) which lower the efficacy. Incorporating measurement of trough levels and ADA (therapeutic drug monitoring) may prevent the development of neutralizing ADA or could contribute to more optimal treatment strategies if ADA are already formed. The aim of this review was to investigate the role of therapeutic drug monitoring in children and adolescents with IBD exposed to anti-TNFα agents.

METHODS

A literature search identified publications that measured anti-TNFα drug trough levels and/or ADA in children or adolescents with IBD. Studies were eligible when (1) article was written in English, (2) original data were available, (3) full text article or abstract was available, (4) measurement of antibodies against anti-TNFα drugs or trough level of anti-TNFα drugs were reported, and (5) levels were measured in pediatric patients with IBD.

RESULTS

The search yielded 811 articles, of which 795 articles were excluded based on title or abstract. A total of 14 studies were included in the review.

CONCLUSIONS

Therapeutic drug monitoring within the pediatric IBD population certainly has a potential benefit. As occurrence of immune reactions to anti-TNFα agents varies widely, incorporating measurement of IFX trough levels at week 8 or week 14 predicts therapy response and allows for dose adjustments to reach therapeutic drug concentrations. However, a clinically relevant cutoff level for ADA has not been defined yet, and the optimal intervention strategy still has to be determined.