Review article: novel oral-targeted therapies in inflammatory bowel disease

Revisiting Structure-activity Relationships: Unleashing the potential of selective Janus kinase 1 inhibitors

Janus kinases (JAKs), a kind of non-receptor tyrosine kinases, the function has been implicated in the regulation of cell proliferation, differentiation and apoptosis, immune, inflammatory response and malignancies. Among them, JAK1 represents an essential target for modulating cytokines involved in inflammation and immune function. Rheumatoid arthritis, atopic dermatitis, ulcerative colitis and psoriatic arthritis are areas where approved JAK1 drugs have been applied for the treatment. In the review, we provided a brief introduction to JAK1 inhibitors in market and clinical trials. The structures of high active JAK1 compounds (IC50 ≤ 0.1 nM) were highlighted, with primary focus on structure-activity relationship and selectivity. Moreover, the druggability processes of approved drugs and high active compounds were analyzed. In addition, the issues involved in JAK1 compounds clinical application as well as strategies to surmount these challenges, were discussed.

Clinical use of biologics for Crohn's disease in adults: lessons learned from real-world studies

INTRODUCTION

The therapeutic armamentarium for managing Crohn's disease (CD) has expanded significantly in recent decades. Several biologics with three different mechanisms of action [anti-tumor necrosis factor (TNF)-α, anti-integrin α4β7, and anti-IL 12/23] are currently available to manage CD.

AREA COVERED

This narrative review aims to summarize the most significant efficacy and safety data on the use of infliximab (IFX), adalimumab (ADA), vedolizumab (VDZ) and ustekinumab (UST) for the treatment of CD obtained from studies conducted in the real world (RW), compared to the results of randomized clinical trials (RCTs).

EXPERT OPINION

RW studies reported that biologic agents included in this analysis have higher remission rates and lower adverse event rates than findings from RCTs for treating patients with CD. All biological agents have proven effective and safe in RW studies, even when using biosimilars or switching to subcutaneous administration of the molecules for which they are available. Finally, anti-TNF-α agents, particularly IFX, have a higher rate of adverse events (AEs) than VDZ and UST. Therefore, patients at higher risk of AEs may benefit from other biologics than anti-TNF-α. However, further long-term RW studies are needed to confirm these findings.

Selected Cytokines and Metalloproteinases in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a collective term for two diseases: ulcerative colitis (UC) and Crohn's disease (CD). There are many factors, e.g., genetic, environmental and immunological, that increase the likelihood of these diseases. Indicators of IBDs include extracellular matrix metalloproteinases (MMPs). The aim of this review is to present data on the role of selected cytokines and metalloproteinases in IBD. In recent years, more and more transcriptomic studies are emerging. These studies are improving the characterization of the cytokine microenvironment inside inflamed tissue. It is observed that the levels of several cytokines are consistently increased in inflamed tissue in IBD, both in UC and CD. This review shows that MMPs play a major role in the pathology of inflammatory processes, cancer, and IBD. IBD-associated inflammation is associated with increased expression of MMPs and reduced ability of tissue inhibitors of metalloproteinases (TIMPs) to inhibit their action. In IBD patients in tissues that are inflamed, MMPs are produced in excess and TIMP activity is not sufficient to block MMPs. This review is based on our personal selection of the literature that was retrieved by a selective search in PubMed using the terms "Inflammatory bowel disease" and "pathogenesis of Inflammatory bowel diseases" that includes systematic reviews, meta-analyses, and clinical trials. The involvement of the immune system in the pathophysiology of IBD is reviewed in terms of the role of the cytokines and metalloproteinases involved.

QSAR-driven screening uncovers and designs novel pyrimidine-4,6-diamine derivatives as potent JAK3 inhibitors

This study presents a robust and integrated methodology that harnesses a range of computational techniques to facilitate the design and prediction of new inhibitors targeting the JAK3/STAT pathway. This methodology encompasses several strategies, including QSAR analysis, pharmacophore modeling, ADMET prediction, covalent docking, molecular dynamics (MD) simulations, and the calculation of binding free energies (MM/GBSA). An efficacious QSAR model was meticulously crafted through the employment of multiple linear regression (MLR). The initial MLR model underwent further refinement employing an artificial neural network (ANN) methodology aimed at minimizing predictive errors. Notably, both MLR and ANN exhibited commendable performance, showcasing R2 values of 0.89 and 0.95, respectively. The model's precision was assessed via leave-one-out cross-validation (CV) yielding a Q2 value of 0.65, supplemented by rigorous Y-randomization. , The pharmacophore model effectively differentiated between active and inactive drugs, identifying potential JAK3 inhibitors, and demonstrated validity with an ROC value of 0.86. The newly discovered and designed inhibitors exhibited high inhibitory potency, ranging from 6 to 8, as accurately predicted by the QSAR models. Comparative analysis with FDA-approved Tofacitinib revealed that the new compounds exhibited promising ADMET properties and strong covalent docking (CovDock) interactions. The stability of the new discovered and designed inhibitors within the JAK3 binding site was confirmed through 500 ns MD simulations, while MM/GBSA calculations supported their binding affinity. Additionally, a retrosynthetic study was conducted to facilitate the synthesis of these potential JAK3/STAT inhibitors. The overall integrated approach demonstrates the feasibility of designing novel JAK3/STAT inhibitors with robust efficacy and excellent ADMET characteristics that surpass Tofacitinib by a significant margin.Communicated by Ramaswamy H. Sarma.

Discovery and Optimization of Novel hDHODH Inhibitors for the Treatment of Inflammatory Bowel Disease

As a key rate-limiting enzyme in the de novo synthesis of pyrimidine nucleotides, human dihydroorotate dehydrogenase (hDHODH) is considered a known target for the treatment of autoimmune diseases, including inflammatory bowel disease (IBD). Herein, BAY 41-2272 with a 1H-pyrazolo[3,4-b]pyridine scaffold was identified as an hDHODH inhibitor by screening an active compound library containing 5091 molecules. Further optimization led to 2-(1-(2-chloro-6-fluorobenzyl)-1H-pyrrolo[2,3-b]pyridin-3-yl)-5-cyclopropylpyrimidin-4-amine (w2), which was found to be the most promising and drug-like compound with potent inhibitory activity against hDHODH (IC50 = 173.4 nM). Compound w2 demonstrated acceptable pharmacokinetic characteristics and alleviated the severity of acute ulcerative colitis induced by dextran sulfate sodium in a dose-dependent manner. Notably, w2 exerted better therapeutic effects on ulcerative colitis than hDHODH inhibitor vidofludimus and Janus kinase (JAK) inhibitor tofacitinib. Taken together, w2 is a promising hDHODH inhibitor for the treatment of IBD and deserves to be developed as a preclinical candidate.

Role of Serum Interleukin-6, Interleukin-1β and Interleukin-10 in Assessment of Disease Activity and Nutritional Status in Patients with Inflammatory Bowel Disease

Inflammatory bowel diseases (IBD) are characterised by multifactorial and chronic inflammation. Much attention has been paid to immune dysfunction in inflammatory bowel diseases. The aim of this study was to assess the usefulness of serum IL-6, IL-1β and IL-10 in determining the activity and nutritional status in IBD patients. The case-control study was carried out on 82 patients with IBD; the control group consisted of 25 clinically healthy subjects. The serum concentrations of IL-6, IL-1 β and IL-10 were determined by the quantitative sandwich enzyme-linked immunosorbent assay. There were no significant differences in IL-6 and IL-1β levels in UC and CD patients according to disease activity as assessed by the Montreal classification, Partial Mayo Score and CDAI. Significantly higher IL-6 levels were found in patients with low body fat in comparison to patients with normal body fat. Furthermore, significantly higher mean IL-6 levels were observed in patients with excess body fat in comparison to patients with normal body fat, and also in comparison to patients with deficient body fat. IL-6 and IL-1β may provide extra information regarding the nutritional status of IBD patients. IL-10 can be considered a non-invasive biomarker of IBD activity.

Orally Administered Platinum Nanomarkers for Urinary Monitoring of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic relapsing autoimmune disease with rising incidence worldwide. There is an increasing desire for non-invasive diagnostic tools to enable simple and sensitive IBD monitoring. Here, we report an orally administered nanosensor which will dissociate into ultrasmall platinum nanoclusters (PtNCs) in IBD-related inflammatory microenvironments. By exploiting the enzyme-mimicking activity of PtNCs and the precise bandpass filterability of kidney, the released-PtNCs can be detected in a scalable urinary readout, such as fluorescence and volumetric bar-chart chip (V-Chip), for point-of-care (POC) analysis. Our results demonstrate that the nanosensors exhibit significant signal differences between IBD-model mice and healthy mice, which is more sensitive than clinical ELISA assay based on fecal calprotectin. Such a non-invasive diagnostic modality significantly assists in the personalized assessment of pharmacological and follow-up efficacy. We envision that this modular conception will promote the rapid diagnosis of diverse diseases by changing specific responsive components.

Blockade of PGK1 and ALDOA enhances bilirubin control of Th17 cells in Crohn's disease

Unconjugated bilirubin (UCB) confers Th17-cells immunosuppressive features by activating aryl-hydrocarbon-receptor, a modulator of toxin and adaptive immune responses. In Crohn's disease, Th17-cells fail to acquire regulatory properties in response to UCB, remaining at an inflammatory/pathogenic state. Here we show that UCB modulates Th17-cell metabolism by limiting glycolysis and through downregulation of glycolysis-related genes, namely phosphoglycerate-kinase-1 (PGK1) and aldolase-A (ALDOA). Th17-cells of Crohn's disease patients display heightened PGK1 and ALDOA and defective response to UCB. Silencing of PGK1 or ALDOA restores Th17-cell response to UCB, as reflected by increase in immunoregulatory markers like FOXP3, IL-10 and CD39. In vivo, PGK1 and ALDOA silencing enhances UCB salutary effects in trinitro-benzene-sulfonic-acid-induced colitis in NOD/scid/gamma humanized mice where control over disease activity and enhanced immunoregulatory phenotypes are achieved. PGK1 and/or ALDOA blockade might have therapeutic effects in Crohn's disease by favoring acquisition of regulatory properties by Th17-cells along with control over their pathogenic potential.

Review of potential medical treatments for middle ear cholesteatoma

Middle ear cholesteatoma (MEC), is a destructive, and locally invasive lesion in the middle ear driven by inflammation with an annual incidence of 10 per 100,000. Surgical extraction/excision remains the only treatment strategy available and recurrence is high (up to 40%), therefore developing the first pharmaceutical treatments for MEC is desperately required. This review was targeted at connecting the dysregulated inflammatory network of MEC to pathogenesis and identification of pharmaceutical targets. We summarized the numerous basic research endeavors undertaken over the last 30+ years to identify the key targets in the dysregulated inflammatory pathways and judged the level of evidence for a given target if it was generated by in vitro, in vivo or clinical experiments. MEC pathogenesis was found to be connected to cytokines characteristic for Th1, Th17 and M1 cells. In addition, we found that the inflammation created damage associated molecular patterns (DAMPs), which further promoted inflammation. Similar positive feedback loops have already been described for other Th1/Th17 driven inflammatory diseases (arthritis, Crohn’s disease or multiple sclerosis). A wide-ranging search for molecular targeted therapies (MTT) led to the discovery of over a hundred clinically approved drugs already applied in precision medicine. Based on exclusion criteria designed to enable fast translation as well as efficacy, we condensed the numerous MTTs down to 13 top drugs. The review should serve as groundwork for the primary goal, which is to provide potential pharmaceutical therapies to MEC patients for the first time in history.

Identification of Gene Expression Profiles Associated with an Increased Risk of Post-Operative Recurrence in Crohn's Disease

BACKGROUND AND AIMS

Ileocolonic resection is frequently needed in the course of Crohn's disease [CD] treatment and post-operative recurrence is extremely common. Our main objective was to analyse gene expression in the mucosa of CD patients at the time of surgery and at post-operative endoscopy, in order to identify predictors and mechanisms of early endoscopic recurrence.

METHODS

We conducted transcriptome analyses on ileal mucosa samples collected from inflamed sections of the surgical specimens [n = 200], from ileal resection margins [n = 149] and in the neo-terminal ileum 6 months after surgery [n = 122]; these were compared with non-inflammatory bowel disease controls [n = 25]. The primary endpoint was post-operative endoscopic recurrence at 6 months. We applied regression models to identify gene signatures predicting endoscopic recurrence.

RESULTS

Chronic inflammation was associated with strong expression of inflammatory genes [IL-6, IL-8, IL-1B] and decreased expression of genes involved in metabolic processes, but with a high inter-individual heterogeneity. Gene signatures associated with early endoscopic recurrence were mainly characterized by upregulation of TNFα, IFNγ, IL23A and IL17A. Pathway analyses showed that upregulation of mitochondrial dysfunction within the inflamed sections and JAK/STAT at the ileal margin were predictive of post-operative recurrence. A combined model integrating these top pathway signatures improved the prediction of endoscopic recurrence [area under the curve of 0.79]. STAT3 phosphorylation at the surgical ileal margin was associated with severe recurrence at 6 months.

CONCLUSION

We identified several biological pathways in surgical ileal mucosa specimens associated with an increased risk of disease recurrence. Integration of the JAK/STAT and mitochondrial dysfunction pathways in the clinical model improved the prediction of post-operative recurrence.

The JAK/STAT signaling pathway: from bench to clinic

The Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway was discovered more than a quarter-century ago. As a fulcrum of many vital cellular processes, the JAK/STAT pathway constitutes a rapid membrane-to-nucleus signaling module and induces the expression of various critical mediators of cancer and inflammation. Growing evidence suggests that dysregulation of the JAK/STAT pathway is associated with various cancers and autoimmune diseases. In this review, we discuss the current knowledge about the composition, activation, and regulation of the JAK/STAT pathway. Moreover, we highlight the role of the JAK/STAT pathway and its inhibitors in various diseases.

Selective Tyrosine Kinase 2 Inhibition for Treatment of Inflammatory Bowel Disease: New Hope on the Rise

Conventional systemic and biologic agents are the mainstay of inflammatory bowel disease (IBD) management; however, many of these agents are associated with loss of clinical response, highlighting the need for effective, novel targeted therapies. Janus kinase (JAK) 1-3 and tyrosine kinase 2 (TYK2) mediate signal transduction events downstream of multiple cytokine receptors that regulate targeted gene transcription, including the interleukin-12, interleukin-23, and type I interferon receptors for TYK2. This review summarizes the role of TYK2 signaling in IBD pathogenesis, the differential selectivity of TYK2 inhibitors, and the potential clinical implications of TYK2 inhibition in IBD. A PubMed literature review was conducted to identify studies of JAK1-3 and TYK2 inhibitors in IBD and other immune-mediated inflammatory diseases. Key efficacy and safety information was extracted and summarized. Pan-JAK inhibitors provide inconsistent efficacy in patients with IBD and are associated with toxicities resulting from a lack of selectivity at therapeutic dosages. Selective inhibition of TYK2 signaling via an allosteric mechanism, with an agent that binds to the regulatory (pseudokinase) domain, may reduce potential toxicities typically associated with JAK1-3 inhibitors. Deucravacitinib, a novel, oral, selective TYK2 inhibitor, and brepocitinib and PF-06826647, TYK2 inhibitors that bind to the active site in the catalytic domain, are in development for IBD and other immune-mediated inflammatory diseases. Allosteric TYK2 inhibition is more selective than JAK1-3 inhibition and has the potential to limit toxicities typically associated with JAK1-3 inhibitors. Future studies will be important in establishing the role of selective, allosteric TYK2 inhibition in the management of IBD.

Macrophage-Biomimetic Nanoparticles Ameliorate Ulcerative Colitis through Reducing Inflammatory Factors Expression

Background and Aims

Inflammatory mediator S100A9 is dramatically elevated in ulcerative colitis and correlates with disease severity. S100A9 is a potential molecule to target for the treatment of colitis, but to date, there is no effective targeting method. The aim of this study was to develop a safe and effective nano-delivery system targeting S100A9 and to evaluate its therapeutic efficacy in ulcerative colitis mouse model.

Methods

We designed an oral nano-delivery system using poly (lactic acid-glycolic acid) (PLGA)-loaded S100A9 inhibitor tasquinimod to synthesize PLGA-TAS nanoparticles. TLR4-overexpressing macrophage membranes (MMs) were used to wrap the nanoparticles to make MM-PLGA-TAS, which allowed the nanoparticles to acquire the ability to specifically enrich the colitis region.

Results

MM-PLGA-TAS was endocytosed by inflammatory phenotype RAW264.7 cells in vitro and can efficiently enrich in inflamed mouse colitis tissue in vivo. A chemically induced ulcerative colitis mouse model was used to evaluate the therapeutic effect of oral MM-PLGA-TAS. MM-PLGA-TAS significantly alleviated the symptoms of ulcerative colitis, and mechanically, MM-PLGA-TAS achieved immunomodulatory and suppressive effects by reducing S100a9 and other cytokines in the colitis region.

Conclusion

We describe a convenient, orally targeted colitis drug delivery system that cures the disease in ulcerative colitis mice. This system substantially increases drug accumulation in inflamed colonic tissue, reduces the risk of systemic exposure, and is a promising therapeutic approach against ulcerative colitis.

Betulinic acid hydroxamate prevents colonic inflammation and fibrosis in murine models of inflammatory bowel disease

Intestinal fibrosis is a common complication of inflammatory bowel disease (IBD) and is defined as an excessive accumulation of scar tissue in the intestinal wall. Intestinal fibrosis occurs in both forms of IBD: ulcerative colitis and Crohn's disease. Small-molecule inhibitors targeting hypoxia-inducing factor (HIF) prolyl-hydroxylases are promising for the development of novel antifibrotic therapies in IBD. Herein, we evaluated the therapeutic efficacy of hydroxamate of betulinic acid (BHA), a hypoxia mimetic derivative of betulinic acid, against IBD in vitro and in vivo. We showed that BAH (5-20 μM) dose-dependently enhanced collagen gel contraction and activated the HIF pathway in NIH-3T3 fibroblasts; BAH treatment also prevented the loss of trans-epithelial electrical resistance induced by proinflammatory cytokines in Caco-2 cells. In two different murine models (TNBS- and DSS-induced IBD) that cause colon fibrosis, oral administration of BAH (20, 50 mg/kg·d, for 17 days) prevented colon inflammation and fibrosis, as detected using immunohistochemistry and qPCR assays. BAH-treated animals showed a significant reduction of fibrotic markers (Tnc, Col1a2, Col3a1, Timp-1, α-SMA) and inflammatory markers (F4/80⁺, CD3⁺, Il-1β, Ccl3) in colon tissue, as well as an improvement in epithelial barrier integrity and wound healing. BHA displayed promising oral bioavailability, no significant activity against a panel of 68 potential pharmacological targets and was devoid of genotoxicity and cardiotoxicity. Taken together, our results provide evidence that oral administration of BAH can alleviate colon inflammation and colitis-associated fibrosis, identifying the enhancement of colon barrier integrity as a possible mechanism of action, and providing a solid rationale for additional clinical studies.

Inflammatory bowel disease in primary immunodeficiency disorders is a heterogeneous clinical entity requiring an individualized treatment strategy: A systematic review

OBJECTIVE

To describe the prevalence, clinical presentation and current treatment regimens of inflammatory bowel disease (IBD) in patients with primary immunodeficiency disorders (PIDs).

METHODS

A systematic review was conducted. The following databases were searched: MEDLINE, Embase, Web of Science, the Cochrane Library and Google Scholar.

RESULTS

A total of 838 articles were identified, of which 36 were included in this review. The prevalence of IBD in PIDs ranges between 3.4% and 61.2%, depending on the underlying PID. Diarrhea and abdominal pain were reported in 64.3% and 52.4% of the patients, respectively. Colon ulceration was the most frequent finding on endoscopic evaluation, while cryptitis, granulomas, ulcerations and neutrophilic/lymphocytic infiltrates were the most frequently reported histopathological abnormalities. Described treatment regimens included oral corticosteroids and other oral immunosuppressive agents, including mesalazine, azathioprine and cyclosporin, leading to clinical improvement in the majority of patients. In case of treatment failure, biological therapies including TNF- α blocking agents, are considered.

CONCLUSIONS

The overall prevalence of IBD in patients with PID is high, but varies between different PIDs. Physicians should be aware of these complications and focus on characteristic symptoms to reduce diagnostic delay and delay in initiation of treatment. Treatment of IBD in PIDs depends on severity of symptoms and may differ between various PIDs based on distinct underlying pathogenesis. An individualized diagnostic and therapeutic approach is therefore warranted.

Expression and function of Smad7 in autoimmune and inflammatory diseases

Transforming growth factor-β (TGF-β) plays a critical role in the pathological processes of various diseases. However, the signaling mechanism of TGF-β in the pathological response remains largely unclear. In this review, we discuss advances in research of Smad7, a member of the I-Smads family and a negative regulator of TGF-β signaling, and mainly review the expression and its function in diseases. Smad7 inhibits the activation of the NF-κB and TGF-β signaling pathways and plays a pivotal role in the prevention and treatment of various diseases. Specifically, Smad7 can not only attenuate growth inhibition, fibrosis, apoptosis, inflammation, and inflammatory T cell differentiation, but also promotes epithelial cells migration or disease development. In this review, we aim to summarize the various biological functions of Smad7 in autoimmune diseases, inflammatory diseases, cancers, and kidney diseases, focusing on the molecular mechanisms of the transcriptional and posttranscriptional regulation of Smad7.

Discovery of 3-(4-(2-((1H-Indol-5-yl)amino)-5-fluoropyrimidin-4-yl)-1H-pyrazol-1-yl)propanenitrile Derivatives as Selective TYK2 Inhibitors for the Treatment of Inflammatory Bowel Disease

TYK2 mediates signaling of IL-23, IL-12, and Type I IFN-driven responses that are critical in immune-mediated diseases. Herein, we report the design, synthesis, and structure-activity relationships (SARs) of 3-(4-(2-((1H-indol-5-yl)amino)-5-fluoropyrimidin-4-yl)-1H-pyrazol-1-yl)propanenitrile derivatives as selective TYK2 inhibitors. Among them, compound 14l exhibited acceptable TYK2 inhibition with an IC50 value of 9 nM, showed satisfactory selectivity characteristics over the other three homologous JAK kinases, and performed good functional potency in the JAK/STAT signaling pathway on lymphocyte lines and human whole blood. In liver microsomal assay studies, the clearance rate and half-life of 14l were 11.4 mL/min/g and 121.6 min, respectively. Furthermore, in a dextran sulfate sodium colitis model, 14l reduced the production of pro-inflammatory cytokines IL-6 and TNF-α and improved the inflammation symptoms of mucosal infiltration, thickening, and edema. Taken together, 14l was a selective TYK2 inhibitor and could be used to treat immune diseases deserving further investigation.

Lymphocyte Activation Gene (LAG)-3 Is Associated With Mucosal Inflammation and Disease Activity in Ulcerative Colitis

BACKGROUND AND AIMS

Lymphocyte activation gene [LAG]-3 is an immune checkpoint and its expression identifies recently activated lymphocytes that may contribute to inflammation. We investigated the role of LAG-3 by analysing its expression and function in immune cells from blood and tissue of patients with ulcerative colitis [UC].

METHODS

The phenotypic properties of LAG-3+ T cells were determined by flow cytometry, qRT-PCR and single-cell RNA-sequencing. LAG-3+ cells were quantified and correlated with disease activity. The functional effects of LAG-3+ cells were tested using a depleting anti-LAG-3 monoclonal antibody [mAb] in a mixed lymphocyte reaction [MLR].

RESULTS

LAG-3+ cells in the blood were negligible. LAG-3+ lymphocytes were markedly increased in inflamed mucosal tissue and both frequencies of LAG-3+ T cells and transcript levels of LAG3 correlated with endoscopic severity. LAG-3 expression was predominantly on effector memory T cells, and single-cell RNA-sequencing revealed LAG3 expression in activated and cytokine-producing T cell subsets. Foxp3+CD25hi Tregs also expressed LAG-3, although most mucosal Tregs were LAG-3-. Mucosal LAG-3+ cells produced mainly interferon γ [IFNγ] and interleukin-17A. LAG-3+ cell numbers decreased in patients who responded to biologics, and remained elevated in non-responders. Treatment with a depleting anti-LAG-3 mAb led to a reduction in proliferation and IFNγ production in an MLR.

CONCLUSIONS

LAG-3+ cells are increased in the inflamed mucosa, predominantly on effector memory T cells with an activated phenotype and their cell numbers positively correlate with disease activity. Depleting LAG-3 eliminates activated proliferating T cells, and hence LAG-3 could be a therapeutic target in UC.

Small molecule oral targeted therapies in ulcerative colitis

The incidence and prevalence of ulcerative colitis are increasing globally. Although the exact cause and pathogenesis of this disease is unclear, research has led to a better understanding of the condition and to identification of new targets for therapy, which in turn has encouraged the development of new therapies. As well as biologic therapies, which have changed the way inflammatory bowel disease is managed, small molecules have been developed for the treatment of ulcerative colitis. These small molecule treatments are orally administered and are likely to bring a substantial shift in the way this chronic disease is treated. Oral therapies offer many advantages over infusion therapies, such as ease of use, increased acceptability by patients, and reduction of cost. This Review focuses not only on oral therapies that have been approved for use in ulcerative colitis, but also on those that are in development, providing a comprehensive overview for clinicians of available oral therapies and drugs that are likely to become available. We have also reviewed drugs that have shown promise in preclinical studies and could be effective future therapies.

Predictors of response and disease course in patients with inflammatory bowel disease treated with biological therapy-the Danish IBD Biobank Project: protocol for a multicentre prospective cohort study

INTRODUCTION

Inflammatory bowel diseases (IBDs) are chronic diseases of unknown cause characterised by a progressive and unpredictable disease course. In the last decade, biological treatment has become a cornerstone in the treatment of IBD. However, one-in-three-to-four patients do not respond to first-line biological agents and another third of patients see their response diminish over time. This highlights an unmet need for optimising the use of biologicals and the prediction of treatment response. Considering the multifaceted nature of IBD, we hypothesise that multiomics profiling of sequential samples from single patients could facilitate the discovery of predictive biomarkers of response to biological therapy and disease course.

METHODS

This is a multicentre prospective cohort study which will enrol 840 biological-naïve patients with IBD who initiate biological therapy in a 3-year period. Primary outcomes are the occurrence of primary non-response (evaluated at weeks 14-16) and loss of response (evaluated during entire follow-up in patients who obtain partial or full response after induction period). Each patient will be followed up for their clinical data for at least 1 year or till the end of study period (up to 4 years). Blood and stool samples will be collected sequentially during the first year of biological treatment. Intestinal tissue will be sampled after 1 year of treatment and whenever an endoscopy is performed. Samples will undergo transcriptomic, proteomic and microbial DNA analyses. Omics data will be integrated with clinical data to identify a panel of predictive biomarkers of response to biological therapy and disease behaviour in patients with IBD.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Danish Ethics Committee (H-18064178). Inclusion is ongoing at three study centres and will be initiated in two additional centres. Both positive and negative study results will be disseminated through peer-reviewed journals according to Strengthening the Reporting of Observational Studies in Epidemiology guidelines, as well as presented at international conferences.

Inflammatory bowel disease: between genetics and microbiota

Inflammatory bowel disease (IBD) is a chronic relapsing inflammatory disease that can involve any part of the gastrointestinal tract. It includes two main disorders: Crohn's disease (CD) and Ulcerative colitis (UC). CD and UC often share a similar clinical presentation; however, they affect distinct parts of the GI Tract with a different gut wall inflammatory extent. Ultimately, IBD seems to emanate from an uncontrollably continuous inflammatory process arising against the intestinal microbiome in a genetically susceptible individual. It is a multifactorial disease stemming from the impact of both environmental and genetic components on the intestinal microbiome. Furthermore, IBD genetics has gained a lot of attention. Around 200 loci were identified as imparting an increased risk for IBD. Few of them were heavily investigated and determined as highly linked to IBD. These genes, as discussed below, include NOD2, ATG16L1, IRGM, LRRK2, PTPN2, IL23R, Il10, Il10RA, Il10RB, CDH1 and HNF4α among others. Consequently, the incorporation of a genetic panel covering these key genes would markedly enhance the diagnosis and evaluation of IBD.

Emerging targets of disease-modifying therapy for systemic sclerosis

Systemic sclerosis (SSc) has the highest cause-specific mortality of all the connective tissue diseases, and the aetiology of this complex and heterogeneous condition remains an enigma. Current disease-modifying therapies for SSc predominantly target inflammatory and vascular pathways but have variable and unpredictable clinical efficacy, and none is curative. Moreover, many of these therapies possess undesirable safety profiles and have no appreciable effect on long-term mortality. This Review describes the most promising of the existing therapeutic targets for SSc and places them in the context of our evolving understanding of the pathophysiology of this disease. As well as taking an in-depth look at the immune, inflammatory, vascular and fibrotic pathways implicated in the pathogenesis of SSc, this Review discusses emerging treatment targets and therapeutic strategies. The article concludes with an overview of important unanswered questions in SSc research that might inform the design of future studies of treatments aimed at modifying the course of this disease.

5-Aminosalicylic acid intolerance is associated with a risk of adverse clinical outcomes and dysbiosis in patients with ulcerative colitis

Background/Aims

5-Aminosalicylic acid (ASA) causes intolerance reactions in some patients. This study was performed to examine the prognosis of patients with ulcerative colitis (UC) and 5-ASA intolerance, and to evaluate the potential interaction between 5-ASA intolerance and the intestinal microbiota.

Methods

We performed a retrospective cohort study of patients with UC who visited participating hospitals. The primary endpoint was to compare the incidence of hospitalization within 12 months between the 5-ASA intolerance group and the 5-ASA tolerance group. The secondary endpoint was to compare the risk of adverse clinical outcomes after the start of biologics between the 2 groups. We also assessed the correlation between 5-ASA intolerance and microbial change in an independently recruited cohort of patients with UC.

Results

Of 793 patients, 59 (7.4%) were assigned to the 5-ASA intolerance group and 734 (92.5%) were assigned to the 5-ASA tolerance group. The admission rate and incidence of corticosteroid use were significantly higher in the intolerance than tolerance group (P< 0.001). In 108 patients undergoing treatment with anti-tumor necrosis factor biologics, 5-ASA intolerance increased the incidence of additional induction therapy after starting biologics (P< 0.001). The 5-ASA intolerance group had a greater abundance of bacteria in the genera Faecalibacterium, Streptococcus, and Clostridium than the 5-ASA tolerance group (P< 0.05).

Conclusions

In patients with UC, 5-ASA intolerance is associated with a risk of adverse clinical outcomes and dysbiosis. Bacterial therapeutic optimization of 5-ASA administration may be important for improving the prognosis of patients with UC.

The JAK inhibitor tofacitinib ameliorates immune‑mediated liver injury in mice

The prevalence of immune-mediated liver diseases such as autoimmune liver disease or viral hepatitis has increased in recent years, and the side effects of pre-existing treatments are a worldwide problem. Regulatory T cells (Tregs) and T helper 17 (Th17) cells play important roles in the development of immune-mediated hepatitis and may serve as potential therapeutic targets. Tofacitinib, a new Janus kinase (JAK) inhibitor, is under investigation for the treatment of rheumatoid arthritis; it is also helpful in treating ulcerative colitis and psoriasis. The roles of tofacitinib were investigated in conferring protection against immune-mediated liver injury in mice. T cell-mediated hepatitis was induced by concanavalin A (ConA). The mice in the treatment groups were administered with tofacitinib intragastrically before the ConA injection. Histopathological examination was performed by hematoxylin and eosin (H&E) staining, and the serum transaminase and inflammatory cytokine levels were determined using an automatic biochemistry analysis apparatus or cytometric bead array (CBA) kits. Flow cytometric analysis was used to detect Tregs and Th17 cells. Tofacitinib significantly decreased the hepatic injury induced by ConA and prominently decreased the liver transaminase level. The secretion of several anti-inflammatory cytokines such as interleukin (IL)-10 was upregulated in mice from the treatment group, compared to that in mice treated with ConA alone, while the expression of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) decreased. Tofacitinib treatment increased the number of Tregs and reduced the number of Th17 cells. Furthermore, tofacitinib could relieve liver fibrosis under conditions of autoimmune hepatitis (AIH). The present results indicated that tofacitinib improved immune-mediated hepatitis and restored the impaired Treg/Th17 cell ratio, which suggests that it may serve as a novel treatment approach for immune-mediated liver diseases.

Inhibitors of the Janus Kinases: A New Oral Treatment Option for Ulcerative Colitis

BACKGROUND

The treatment of ulcerative colitis (UC) is based on conventional therapies (aminosalicylates, corticosteroids, and immunosuppressants) and when these are ineffective, biologic drugs. However, in a substantial portion of patients undergoing treatment with biologic agents there is primary or secondary loss of response. Thus, new therapeutic options are been actively explored; among these, there is interest in the Janus kinase (JAK) inhibitors, small molecules that can be administered orally.

METHODS

We carried out an extensive literature search concerning the effects of JAK inhibitors for the treatment of patients with UC.

RESULTS

Tofacitinib is the drug more extensively studied in this setting, and it was recently approved in Europe for the treatment of moderate to severe UC. The available data suggest that this drug can be effective in obtaining clinical and endoscopic remission in UC patients unresponsive to other treatments, even in those previously treated with biologic drugs. In addition, the drug was able to improve significantly the quality of life of these patients. There are still few data available for the treatment of UC with other JAK inhibitors.

CONCLUSIONS

The JAK inhibitors, in particular tofacitinib, are a new class of orally administered drugs effective for the treatment of UC. However, more studies are needed to ascertain the safety of tofacitinib in the long term and whether other compounds of this class may be equally effective.

Oligonucleotides-A Novel Promising Therapeutic Option for IBD

Inflammatory Bowel Diseases (IBD), whose denomination comprehends Crohn's Disease (CD) and Ulcerative Colitis (UC), are intestinal chronic diseases that often require lifelong medical therapy. In the last two decades monoclonal antibodies against the cytokine TNF have become integral parts in the treatment of IBD patients, however there are unwanted side-effects and one third of patients show primary non-response while another subgroup loses response over time. Finding novel drugs which could act as therapies against precise pro-inflammatory molecular targets to avoid unwanted systemic side effects and additionally the process of immunization, represents an important aim for subsequent therapeutic approaches. Oligonucleotide based therapies represent a promising novel concept for the treatment of IBD. The molecular action of oligonucleotides ranges from inhibition of the translational process of mRNA transcripts of pro-inflammatory molecules, to mimicking bacterial DNA which can activate cellular targets for immunomodulation. Alicaforsen, selectively targets ICAM-1 mRNA. ICAM-1 is an adhesion molecule which is upregulated on endothelial cells during IBD, thereby mediating the adhesion and migration of leucocytes from blood to sites of active inflammation. In CD parenteral application of alicaforsen did not show therapeutic efficacy in phase II trials, but it demonstrated an improved efficacy as a topical enema in distal UC. Topical application of alicaforsen might represent a therapeutic perspective for refractory pouchitis as well. SMAD7 is a protein that inhibits the signaling of TGFβ, which is the mainstay of a regulatory counterpart in cellular immune responses. An antisense oligonucleotide against SMAD7 mRNA (mongersen) demonstrated pre-clinical and phase II efficacy in CD, but a phase III clinical trial was stopped due to lack of efficacy. Cobitolimod is a single strand oligonucleotide, which mimics bacterial DNA as its CpG dinucleotide sequences can be recognized by the Toll-like receptor 9 on different immune cells thereby causing induction of different cytokines, for example IL10 and IFNα. Topical application of cobitolimod was studied in UC patients. We will also discuss two other novel oligonucleotides which act on the GATA3 transcription factor (SB012) and on carbohydrate sulfotransferase 15 (STNM01), which could both represent novel promising therapeutic options for the treatment of UC.

Novel Non-biologic Targets for Inflammatory Bowel Disease

PURPOSE OF REVIEW

The biologic era revolutionized the medical management of inflammatory bowel disease (IBD) and allowed for a paradigm shift away from a therapeutic strategy that traditionally relied on corticosteroids and immunomodulators. IBD treatment has now further evolved to encompass novel non-biologic agents.

RECENT FINDINGS

An electronic database search, spanning up to September 2018, was conducted using PubMed, Web of Science, Google Scholar, and Scopus. Abstracts were also reviewed from Digestive Diseases Week, European Crohn's and Colitis Organization congress, Canadian Digestive Diseases Week, and United European Gastroenterology Week. The JAK1/3 inhibitor, tofacitinib, was shown to both induce and maintain clinical remission and mucosal healing in ulcerative colitis (UC). Also, the sphingosine-1-phosphate (SIP) S1P1/S1P5 receptor agonist ozanimod showed benefit with clinical remission and mucosal healing in UC. Anti-trafficking non-biologic therapies such as AJM300 and a phosphodiesterase (PDE) PDE4 inhibitor, apremilast, have shown benefit in terms of clinical response, clinical remission, and mucosal healing in UC. Upadacitinib and filgotinib have shown initial favorable outcomes in CD patients, with further ongoing trials. Non-biologic agents comprise a growing number of mechanisms of action with the promise of safe and effective oral therapy for patients with IBD.

Maneuvering Clinical Pathways for Crohn's Disease

PURPOSE OF REVIEW

Crohn's disease management has changed significantly with increasing use of biologics. We review the recent literature on the clinical management of Crohn's disease and new approaches in selecting and optimizing therapy.

RECENT FINDINGS

Recent studies have addressed the efficacy of proactive anti-TNFα trough level monitoring, the efficacy of biosimilars, and the efficacy and immunogenicity of newer biologics including anti-integrin therapy and anti-IL12/23 therapy. Optimizing anti-TNFα therapy according to trough concentrations correlates with improved remission rates. Patients can be switched from the reference drug to a biosimilar, or vice versa, without a measurable change in efficacy, safety, or immunogenicity. Immunomodulators are effective in decreasing immunogenicity and boosting anti-TNFα drug level. The anti-integrin and anti-IL12/23 therapies are effective as induction and maintenance therapy with low immunogenicity and excellent safety profiles. Patients at high risk for post-operative recurrence should be started on a biologic therapy within 4 weeks post-op. Multiple biologic therapies are currently available for treatment of Crohn's disease including anti-TNFα therapy, anti-integrin therapy, and anti-IL12/23 therapy. The choice of first-line therapy should be based on individual risk-benefit analysis, route of administration, and patient preference. Patient with inadequate response should have their trough level checked and therapy optimized. Therapeutic prophylaxis for post-operative recurrence should be based on patient's risk factors for recurrence.

Targeting Cytokine Signaling and Lymphocyte Traffic via Small Molecules in Inflammatory Bowel Disease: JAK Inhibitors and S1PR Agonists

The inflammatory Bowel diseases (IBDs) are a chronic, relapsing inflammatory diseases of the gastrointestinal tract with heterogeneous behavior and prognosis. The introduction of biological therapies including anti-TNF, anti-IL-12/23, and anti-integrins, has revolutionized the treatment of IBD, but these drugs are not universally effective. Due to the complex molecular structures of biologics, they are uniformly immunogenic. New discoveries concerning the underlying mechanisms involved in the pathogenesis of IBD have allowed for progress in the development of new treatment options. The advantage of small molecules (SMs) over biological therapies includes their lack of immunogenicity, short half-life, oral administration, and low manufacturing cost. Among these, the Janus Kinases (JAKs) inhibition has emerged as a novel strategy to modulate downstream cytokine signaling during immune-mediated diseases. These drugs target various cytokine signaling pathways that participate in the pathogenesis of IBD. Tofacitinib, a JAK inhibitor targeting predominantly JAK1 and JAK3, has been approved for the treatment of ulcerative colitis (UC), and there are other specific JAK inhibitors under development that may be effective in Crohn's. Similarly, the traffic of lymphocytes can now be targeted by another SM. Sphingosine-1-phosphate receptor (S1PR) agonism is a novel strategy that acts, in part, by interfering with lymphocyte recirculation, through blockade of lymphocyte egress from lymph nodes. S1PR agonists are being studied in IBD and other immune-mediated disorders. This review will focus on SM drugs approved and under development, including JAK inhibitors (tofacitinib, filgotinib, upadacitinib, peficitinib) and S1PR agonists (KRP-203, fingolimod, ozanimod, etrasimod, amiselimod), and their mechanism of action.

Selective Tyk2 inhibitors as potential therapeutic agents: a patent review (2015-2018)

INTRODUCTION

Tyrosine kinase 2 (Tyk2) is a non-receptor tyrosine-protein kinase, an enzyme that in humans is encoded by the TYK2 gene. Tyk2, together with three other family subtypes, namely, Jak1, Jak2, and Jak3, belong to the JAK family. Before 2014, far more publications and patents appeared in public domain attributing to the development of selective Jak2 and Jak3 inhibitors than those for selective Tyk2 and Jak1 inhibitors.

AREAS COVERED

This review sought to give an overview of patents related to small molecule selective Tyk2 inhibitors published from 2015 to 2018. The article also covers clinical activities of small molecule selective Tyk2 inhibitors in recent years.

EXPERT OPINION

As a key component of the JAK-STAT signaling pathway, Tyk2 regulates INFα, IL12, and IL23. Selective inhibition of Tyk2 can provide pharmacological benefits in the treatment of many diseases such as psoriasis, systemic lupus erythematosus (SLE), inflammatory bowel disease (IBD), rheumatoid arthritis (RA), cancer, and diabetes. The selectivity against other Jak family subtypes (such as Jak2) is crucial in order to minimize the potential side effects and to maximize the desired pharmacological effects. In this context, this review of recent selective Tyk2 inhibitor patents may prove valid, interesting, and promising within the therapeutic paradigm.

Novel oral-targeted therapies for mucosal healing in ulcerative colitis

Ulcerative colitis (UC), a chronic, relapsing, remitting disease of the colon and rectum, is characterized by inflammatory ulceration of the mucosa. Current UC therapy relies on controlling acute episodes and preventing relapse. To predict modifications in the natural course of UC, mucosal healing (MH) has emerged as a major treatment goal. Endoscopic evaluation is considered the gold standard for assessing MH, which can be achieved by conventional drugs and biologics in many, but not all, patients. Consequently, interest is focusing on the development of new substances for UC therapy, and new oral agents are in the pipeline. This review will focus on the ability of newly developed oral drugs to induce and maintain MH in UC patients.