New biologics and small molecules in inflammatory bowel disease: an update

Biomarkers in inflammatory bowel disease: a practical guide

Inflammatory bowel disease (IBD), comprising ulcerative colitis (UC) and Crohn's disease (CD), is a costly condition in terms of morbidity and healthcare utilization, with an increasing prevalence now approaching 1% in the Western world. Endoscopic assessment of IBD remains the gold standard for diagnosis, evaluation of treatment response and determination of post-operative recurrence, but is expensive and invasive. Biomarkers can facilitate non-invasive disease assessment, with C-reactive protein and faecal calprotectin as the most widely available biomarkers in current clinical practice. This narrative review summarizes the evidence for their use in both UC and CD and offers practical guidance for healthcare providers taking into account the limitations of biomarker interpretation. We present evidence for the future use of novel biomarkers in IBD and discuss how biomarker discovery could deliver the goal of precision medicine in IBD.

Microbiota therapeutics for inflammatory bowel disease: the way forward

Microbiota therapeutics that transplant faecal material from healthy donors to people with mild-to-moderate ulcerative colitis have shown the potential to induce remission in about 30% of participants in small, phase 2 clinical trials. Despite this substantial achievement, the field needs to leverage the insights gained from these trials and progress towards phase 3 clinical trials and drug approval, while identifying the distinct clinical niche for this new therapeutic modality within inflammatory bowel disease (IBD) therapeutics. We describe the lessons that can be learned from past studies of microbiota therapeutics, from full spectrum donor stool to defined products manufactured in vitro. We explore the actionable insights these lessons provide on the design of near-term studies and future trajectories for the integration of microbiota therapeutics in the treatment of IBD. If successful, microbiota therapeutics will provide a powerful orthogonal approach (complementing or in combination with existing immunomodulatory drugs) to raise the therapeutic ceiling for the many non-responders and partial responders within the IBD patient population.

Safety, tolerability, and pharmacokinetics of single- and multiple-ascending doses of olamkicept: Results from randomized, placebo-controlled, first-in-human phase I trials

Olamkicept selectively inhibits the cytokine interleukin-6 (IL-6) trans-signaling pathway without blocking the classic pathway and is a promising immunoregulatory therapy for inflammatory bowel disease (IBD). These first-in-human, randomized, placebo-controlled, single- (SAD) and multiple-ascending dose (MAD) trials evaluated olamkicept safety, tolerability, pharmacokinetic, and pharmacodynamic characteristics. Doses tested in the SAD trial included seven single intravenous doses (0.75, 7.5, 75, 150, 300, 600, and 750 mg) and one subcutaneous (SC) dose (60 mg) given to healthy subjects (N = 64), and three intravenous doses (75 mg, 300 mg, and 750 mg) given to patients with Crohn's disease (CD; N = 24). Doses tested in the MAD trial included multiple intravenous doses (75, 300, and 600 mg once weekly for 4 weeks) given to healthy subjects (N = 24). No severe or serious treatment-emergent adverse events (TEAEs) were recorded. The most common TEAEs were headache, nasopharyngitis, and myalgia in the SAD trial, and diarrhea, headache, and cough in the MAD trial. Infusion-related reactions occurred in one and two subjects in the SAD and MAD trial, respectively, leading to treatment discontinuation in the MAD trial. Olamkicept showed dose-independent pharmacokinetics after single and multiple administrations, and there was no major difference in systemic exposure between healthy subjects and patients with CD. Complete target engagement (inhibition of phosphorylation of signal transducer and activator of transcription-3) was achieved in blood around or above olamkicept serum concentrations of 1-5 μg/mL. Overall, these results suggest that olamkicept is safe and well-tolerated in healthy subjects and patients with CD after single intravenous/SC and multiple intravenous administrations.

Bioinspired and biomimetic strategies for inflammatory bowel disease therapy

Inflammatory bowel disease (IBD) is an idiopathic chronic inflammatory bowel disease with high morbidity and an increased risk of cancer or death, resulting in a heavy societal medical burden. While current treatment modalities have been successful in achieving long-term remission and reducing the risk of complications, IBD remains incurable. Nanomedicine has the potential to address the high toxic side effects and low efficacy in IBD treatment. However, synthesized nanomedicines typically exhibit some degree of immune rejection, off-target effects, and a poor ability to cross biological barriers, limiting the development of clinical applications. The emergence of bionic materials and bionic technologies has reshaped the landscape in novel pharmaceutical fields. Biomimetic drug-delivery systems can effectively improve biocompatibility and reduce immunogenicity. Some bioinspired strategies can mimic specific components, targets or immune mechanisms in pathological processes to produce targeting effects for precise disease control. This article highlights recent research on bioinspired and biomimetic strategies for the treatment of IBD and discusses the challenges and future directions in the field to advance the treatment of IBD.

Antibiotics influence the risk of anti-drug antibody formation during anti-TNF therapy in Chinese inflammatory bowel disease patients

Aims: The formation of anti-drug antibodies (ADAs) during anti-tumor necrosis factor (anti-TNF) therapy is reported to lead to reducing serum drug levels, which may bring about a loss of response to treatment. Previous research has suggested an association between specific antibiotic classes and ADA formation during anti-TNF therapy. However, there are few studies specifically examining this association in Chinese inflammatory bowel disease (IBD) patients. Therefore, our study aimed to evaluate the possible effect of antibiotic use on ADA formation to anti-TNF therapy in Chinese patients with IBD. Methods: A total of 166 patients with IBD, including 149 with Crohn's disease (CD) and 17 with ulcerative colitis (UC), were included in this retrospective analysis. These patients were initially treated with anti-TNF therapy (infliximab or adalimumab) after January 2018 and reviewed with available ADA levels before October 2023. After univariable analysis of all the variables, a multivariate Cox proportional hazards model was used to assess the association between antibiotic use and ADA development. Results: Among 166 IBD patients treated with infliximab (108/166, 65.1%) or adalimumab (58/166, 34.9%), 31 patients (18.7%) were measured as positive ADA levels. Cox proportional hazard model demonstrated an increased risk of ADA formation in IBD patients who used β-lactam-β-lactamase inhibitor combinations (BL-BLIs) (HR = 5.143, 95%CI 1.136-23.270, p = 0.033), or nitroimidazoles (HR = 4.635, 95%CI 1.641-13.089, p = 0.004) during 12 months before the ADA test. On the contrary, a reduced risk was noted in patients treated with fluoroquinolones (HR = 0.258, 95% CI 0.072-0.924, p = 0.037). Moreover, the median serum infliximab or adalimumab concentration in patients with positive ADA levels was significantly lower than that in patients with negative ADA levels (infliximab: 0.30 vs. 1.85 μg/mL, p < 0.0001; adalimumab: 0.45 vs. 7.55 μg/mL, p = 0.0121). Conclusion: ADA development is associated with various antibiotic classes. BL-BLIs and nitroimidazoles might increase the risk of ADA formation during anti-TNF therapy in Chinese IBD patients, while the treatment with fluoroquinolones could probably reduce such risk. There were certain limitations in the retrospective analysis of the study, therefore, the results are just for reference, and other studies are needed to further confirm our findings.

Krill Oil and Its Bioactive Components as a Potential Therapy for Inflammatory Bowel Disease: Insights from In Vivo and In Vitro Studies

Krill oil is extracted from krill, a small crustacean in the Antarctic Ocean. It has received growing attention because of krill oil's unique properties and diverse health benefits. Recent experimental and clinical studies suggest that it has potential therapeutic benefits in preventing the development of a range of chronic conditions, including inflammatory bowel disease (IBD). Krill oil is enriched with long-chain n-3 polyunsaturated fatty acids, especially eicosapentaenoic and docosahexaenoic acids, and the potent antioxidant astaxanthin, contributing to its therapeutic properties. The possible underlying mechanisms of krill oil's health benefits include anti-inflammatory and antioxidant actions, maintaining intestinal barrier functions, and modulating gut microbiota. This review aims to provide an overview of the beneficial effects of krill oil and its bioactive components on intestinal inflammation and to discuss the findings on the molecular mechanisms associated with the role of krill oil in IBD prevention and treatment.

Anti-Inflammatory Properties of the Citrus Flavonoid Diosmetin: An Updated Review of Experimental Models

Inflammation is an essential contributor to various human diseases. Diosmetin (3',5,7-trihydroxy-4'-methoxyflavone), a citrus flavonoid, can be used as an anti-inflammatory agent. All the information in this article was collected from various research papers from online scientific databases such as PubMed and Web of Science. These studies have demonstrated that diosmetin can slow down the progression of inflammation by inhibiting the production of inflammatory mediators through modulating related pathways, predominantly the nuclear factor-κB (NF-κB) signaling pathway. In this review, we discuss the anti-inflammatory properties of diosmetin in cellular and animal models of various inflammatory diseases for the first time. We have identified some deficiencies in current research and offer suggestions for further advancement. In conclusion, accumulating evidence so far suggests a very important role for diosmetin in the treatment of various inflammatory disorders and suggests it is a candidate worthy of in-depth investigation.

Risk factors for malignancy and serious infection in patients with inflammatory bowel disease: a retrospective analysis

BACKGROUND

Patients with inflammatory bowel disease (IBD) are at increased risk of malignancy and infection compared to the general population.

AIMS

We aim to identify risk factors for malignancy or serious infection in our IBD cohort.

METHODS

Patients with IBD from a single tertiary referral centre were included. Demographic and clinical details, including immunosuppressant exposure, were collected and medical records retrospectively screened for adverse events, including malignancy or infection requiring hospitalisation. Logistic regression was used to evaluate risk factors for adverse events.

RESULTS

Five hundred and forty-nine patients with IBD (340 Crohn disease (CD) and 209 ulcerative colitis (UC)) were studied. Forty-eight malignancies, including 39 (81.3%) non-melanoma skin cancers, 3 (6.3%) haematologic malignancies and 6 (15.4%) solid-organ malignancies, were identified, and 92 cases of serious infection were detected. IBD duration (odds ratio (OR) = 1.08; 95% confidence interval (CI) = 1.03-1.13) and ileocolonic CD (OR = 4.96; 95% CI = 1.13-21.71) were associated with increased odds of overall cancer. Compared with patients not previously exposed to the given class of immunosuppression assessed, the development of overall malignancy was not higher with thiopurine exposure (OR = 1.00; 95% CI = 0.50-2.24) or anti-tumour necrosis factor-alpha (TNF-α) exposure (OR = 0.78; 95% CI = 0.37-1.64). Similarly, compared with patients not exposed, infection risk was not affected by thiopurine (OR = 0.74; 95% CI = 0.46-1.20) or anti-TNF exposure (OR = 0.60; 95% CI = 0.38-0.95).

CONCLUSIONS

Factors including ileocolonic CD and increasing IBD duration were associated with higher malignancy risk in this cohort. Compared with non-exposure, patients exposed to thiopurines were not at increased risk of malignancy or serious infection. Similarly, patients exposed to anti-TNF treatment did not experience increased rates of malignancy or serious infection compared to patients not exposed to this treatment.

Novel and emerging drugs for the treatment of Crohn's disease: a review of phase II and III trials

INTRODUCTION

Crohn's disease (CD) is a chronic inflammatory bowel disease characterized by unpredictable flare-ups and periods of remission. While several therapeutic options, such as anti-tumor necrosis factor (TNF), anti-integrin, and interleukin (IL) 12/23 inhibitors, as well as IL-23 and Janus kinase (JAK) inhibitors, have been approved for CD treatment, a substantial number of patients fail to respond adequately or experience a loss of response over time. In recent years, the scientific community has been actively investigating novel agents to address these challenges and improve the management of CD.

AREAS COVERED

This comprehensive narrative review provides an overview of recent developments in CD treatment, summarizing phase 2 and phase 3 clinical trial data. We delve into the clinical efficacy and safety profiles of emerging therapies, encompassing JAK inhibitors, IL-23 inhibitors, anti-adhesion molecules, S1P1 receptor modulators, and combined targeted treatments.

EXPERT OPINION

The armamentarium of CD therapeutic agents is constantly expanding. We analyze pivotal findings from phase 2 and phase 3 CD treatment trials. We also underscore the existing gaps in therapy and the paramount role of ongoing research and innovation in CD management.

Aryl Hydrocarbon Receptor Regulates Muc2 Production Independently of IL-22 during Colitis

We previously reported that an aryl hydrocarbon receptor (AhR) ligand, indole-3-carbinol (I3C), was effective at reducing colitis severity through immune cell-mediated interleukin-22 (IL-22) production. Intestinal epithelial cells (IECs) are also involved in regulating colitis, so we investigated their AhR-mediated mechanisms in the current report. A transcriptome analysis of IECs in wildtype (WT) mice revealed that during colitis, I3C regulated select mucin proteins, which could be attributed to goblet cell development. To address this, experiments under in vivo colitis (mice) or in vitro colon organoid conditions were undertaken to determine how select mucin proteins were altered in the absence or presence of AhR in IECs during I3C treatment. Comparing WT to IEC-specific AhR knockout mice (AhRΔIEC), the results showed that AhR expression was essential in IECs for I3C-mediated protection during colitis. AhR-deficiency also impaired mucin protein expression, particularly mucin 2 (Muc2), independently of IL-22. Collectively, this report highlights the important role of AhR in direct regulation of Muc2. These results provide justification for future studies aimed at determining how AhR might regulate select mucins through mechanisms such as direct transcription binding to enhance production.

Histological Remission Placebo Rates in Ulcerative Colitis Trials: A Systematic Review and Meta-analysis

BACKGROUND

High histologic remission rates have been reported with placebos in randomized controlled trials (RCTs) evaluating ulcerative colitis (UC) therapies and have varied based on trial designs. We performed a systematic review and meta-analysis to quantify placebo histological remission rates and identify factors influencing those rates.

METHODS

MEDLINE, EMBASE, and the Cochrane library were searched from inception of the databases until December 2021. We included placebo-controlled RCTs of adult patients with UC treated with aminosalicylates, corticosteroids, immunosuppressives, biologics, and small molecules. We pooled estimates using a random-effects model and performed subgroup analysis and meta-regression to evaluate the effect of different covariates on placebo rates.

RESULTS

Thirty-three studies (30 induction and 3 maintenance) were included. The overall placebo histological remission rate was 15.7% (95% confidence interval, 12.9%-19%) across all 33 studies. High heterogeneity was observed among studies with I2 = 62.10%. The pooled estimate of histological remission was 15.8% in induction studies and 14.5% in maintenance studies. Subgroup analysis revealed statistically significant differences in placebo rates when accounting for background medications, the intervention drug class, and disease severity (P = .041, .025, and .025, respectively). There was no statistical difference between induction vs maintenance studies or between different histological scales (P = .771, and .075, respectively).

CONCLUSIONS

Placebo histological remission rates range from 13% to 19% in UC RCTs, but studies are highly heterogeneous. Factors found to influence placebo rates include presence of background medications, the drug used, and the disease severity. These observations inform future trial designs to minimize placebo rates and reduce heterogeneity.

Application of Drug Repurposing Approach for Therapeutic Intervention of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), represented by Crohn's disease (CD) and ulcerative colitis (UC), is a chronic inflammatory disorder of the gastrointestinal tract (GIT) characterized by chronic relapsing intestinal inflammation, abdominal pain, cramping, loss of appetite, fatigue, diarrhoea, and weight loss. Although the etiology of IBD remains unclear, it is believed to be an interaction between genes, and environmental factors, such as an imbalance of the intestinal microbiota, changing food habits, an ultra-hygiene environment, and an inappropriate immune system. The development of novel effective therapies is stymied by a lack of understanding of the aetiology of IBD. The current therapy involves the use of aminosalicylates, immunosuppressants, and corticosteroids that can effectively manage symptoms, induce and sustain remission, prevent complications, modify the course of the disease, provide diverse treatment options, showcase advancements in biologic therapies, and enhance the overall quality of life. However, the efficacy of current therapy is overshadowed by a plethora of adverse effects, such as loss of weight, mood swings, skin issues, loss of bone density, higher vulnerability to infections, and elevated blood pressure. Biologicals, like anti-tumour necrosis factor agents, can stimulate an autoimmune response in certain individuals that may diminish the effectiveness of the medication over time, necessitating a switch to alternative treatments. The response of IBD patients to current drug therapy is quite varied, which can lead to disease flares that underlines the urgent need to explore alternative treatment option to address the unmet need of developing new treatment strategies for IBD with high efficacy and fewer adverse effects. Drug repurposing is a novel strategy where existing drugs that have already been validated safe in patients for the management of certain diseases are redeployed to treat other, unindicated diseases. The present narrative review focuses on potential drug candidates that could be repurposed for the management of IBD using on-target and off-target strategies. It covers their preclinical, clinical assessment, mechanism of action, and safety profiles, and forecasts their appropriateness in the management of IBD. The review presents useful insights into the most promising candidates for repurposing, like anti-inflammatory and anti-apoptotic troxerutin, which has been found to improve the DSS-induced colitis in rats, an antiosteoarthritic drug diacetylrhein that has been found to have remarkable ameliorating effects on DSS-induced colitis via anti-oxidant and anti- inflammatory properties and by influencing both apoptosis and pyroptosis. Topiramate, an antiepileptic and anticonvulsant drug, has remarkably decreased overall pathophysiological and histopathological events in the experimental model of IBD in rodents by its cytokine inhibitory action.

Obefazimod: A First-in-class Drug for the Treatment of Ulcerative Colitis

Biologic agents and oral small molecules are the mainstays of inflammatory bowel disease [IBD] management. However, an unmet clinical need remains for additional agents with novel mechanism of action which are effective, safe, and disease-modifying; this is due to the substantial proportion of patients who do not respond, lose response, or develop intolerance to currently marketed products. microRNAs [miRNAs] that play a role in the modulation of signal transduction pathways implicated in the development of IBD hold the potential to be used as therapeutic targets. Recently, a novel first-in-class compound, obefazimod, originally conceived as a human immunodeficiency virus [HIV] infection drug, has shown great promise in phase II induction trials for ulcerative colitis [UC] patients. Findings from the maintenance phases of trials showed that long-term obefazimod treatment provides continued improvement in clinical symptoms of disease, with a substantial proportion of patients in clinical remission, and an overall good safety profile. With a novel mechanism of action, obefazimod is an orally available small molecule with anti-inflammatory properties through the specific and selective upregulation of miR-124 expression. The aim of this paper is to critically review the available evidence related to pharmacokinetics and pharmacodynamics, and to discuss the potential clinical implications of this first-in-class oral small molecule.

Screening Failure in a Large Clinical Trial Centre for Inflammatory Bowel Diseases: Rates, Causes, and Outcomes

BACKGROUND

Patients with inflammatory bowel diseases (IBD) sometimes require investigational medicinal therapy in a clinical trial. Before enrollment, patients must meet strict eligibility criteria, hampering recruitment rates. We investigated the rates, causes, and outcomes of screening failure (SF) in a tertiary IBD center.

METHODS

We reviewed all IBD patients screened for sponsored multicenter phase 1-3 induction studies with available global SF rates between January 2008 and March 2021. We compared our SF rates with the global SF rates. Causes of SF were categorized into disease activity, hematology, chemistry, microbiology, protocol violation, and withdrawal of consent. Patient outcomes were categorized into rescreening for the same trial, screening for another trial, (re)introduction of commercially available therapy, surgery, or watchful waiting.

RESULTS

During the study period, 642 local screenings were performed as part of 53 studies. We identified an overall SF rate of 17.1%, compared with 39.2% in the global study population (P < .00001). Causes of SF at our center included ineligible disease activity (36.4%), microbiology (25.5%), protocol violation (16.4%), withdrawal of consent (9.1%), chemistry (6.4%) and hematology (6.4%). Thirty SFs could have been avoided by prescreening that was more thorough. After SF, 34 patients were rescreened for the same trial, 17 screened for another trial, 38 initiated approved therapy, 9 were referred for surgery, and 12 did not receive further therapy.

CONCLUSIONS

A significant proportion of IBD patients consenting to clinical trials fail their screening. Main causes of SF are ineligible disease activity and abnormal finding on microbiology. Approximately one-fourth of SFs could have been avoided by prescreening that was more thorough.

IL-33's role in the gut immune system: A comprehensive review of its crosstalk and regulation

The intestinal tract is the largest immune organ in the human body, comprising a complex network of immune cells and epithelial cells that perform a variety of functions such as nutrient absorption, digestion, and waste excretion. Maintenance of homeostasis and effective responses to injury in the colonic epithelium are crucial for maintaining homeostasis between these two cell types. The onset and perpetuation of gut inflammation, characterizing inflammatory bowel diseases (IBD), are triggered by constitutive dysregulation of cytokine production. IL-33 is a newly characterized cytokine that has emerged as a critical modulator of inflammatory disorders. IL-33 is constitutively expressed in the nuclei of different cell types such as endothelial, epithelial, and fibroblast-like cells. Upon tissue damage or pathogen encounter, IL-33 is released as an alarmin and signals through a heterodimer receptor that consists of serum Stimulation-2 (ST2) and IL-1 receptor accessory protein (IL-1RAcP). IL-33 has the ability to induce Th2 cytokine production and enhance both Th1 and Th2, as well as Th17 immune responses. Exogenous administration of IL-33 in mice caused pathological changes in most mucosal tissues such as the lung and the gastrointestinal (GI) tract associated with increased production of type 2 cytokines and chemokines. In vivo and in vitro, primary studies have exhibited that IL-33 can activate Th2 cells, mast cells, or basophils to produce type 2 cytokines such as IL-4, IL-5, and IL-13. Moreover, several novel cell populations, collectively referred to as "type 2 innate lymphoid cells," were identified as being IL-33 responsive and are thought to be important for initiating type 2 immunity. Nevertheless, the underlying mechanisms by which IL-33 promotes type 2 immunity in the GI tract remain to be fully understood. Recently, it has been discovered that IL-33 plays important roles in regulatory immune responses. Highly suppressive ST2 + FoxP3+ Tregs subsets regulated by IL-33 were identified in several tissues, including lymphoid organs, gut, lung, and adipose tissues. This review aims to comprehensively summarize the current knowledge on IL-33's role in the gut immune system, its crosstalk, and regulation. The article will provide insights into the potential applications of IL-33-based therapies in the treatment of gut inflammatory disorders.

Evolving cognition of the JAK-STAT signaling pathway: autoimmune disorders and cancer

The Janus kinase (JAK) signal transducer and activator of transcription (JAK-STAT) pathway is an evolutionarily conserved mechanism of transmembrane signal transduction that enables cells to communicate with the exterior environment. Various cytokines, interferons, growth factors, and other specific molecules activate JAK-STAT signaling to drive a series of physiological and pathological processes, including proliferation, metabolism, immune response, inflammation, and malignancy. Dysregulated JAK-STAT signaling and related genetic mutations are strongly associated with immune activation and cancer progression. Insights into the structures and functions of the JAK-STAT pathway have led to the development and approval of diverse drugs for the clinical treatment of diseases. Currently, drugs have been developed to mainly target the JAK-STAT pathway and are commonly divided into three subtypes: cytokine or receptor antibodies, JAK inhibitors, and STAT inhibitors. And novel agents also continue to be developed and tested in preclinical and clinical studies. The effectiveness and safety of each kind of drug also warrant further scientific trials before put into being clinical applications. Here, we review the current understanding of the fundamental composition and function of the JAK-STAT signaling pathway. We also discuss advancements in the understanding of JAK-STAT-related pathogenic mechanisms; targeted JAK-STAT therapies for various diseases, especially immune disorders, and cancers; newly developed JAK inhibitors; and current challenges and directions in the field.

Assessing acute colitis induced by dextran sulfate sodium in rats and its impact on gastrointestinal fluids

Dextran sulfate sodium (DSS) is commonly used to induce colitis in rats. While the DSS-induced colitis rat model can be used to test new oral drug formulations for the treatment of inflammatory bowel disease, the effect of the DSS treatment on the gastrointestinal tract has not been thoroughly characterized. Additionally, the use of different markers to assess and confirm successful induction of colitis is somewhat inconsistent. This study aimed to investigate the DSS model to improve the preclinical evaluation of new oral drug formulations. The induction of colitis was evaluated based on the disease activity index (DAI) score, colon length, histological tissue evaluation, spleen weight, plasma C-reactive protein, and plasma lipocalin-2. Furthermore, the study investigated how the DSS-induced colitis affected the luminal pH, lipase activity, and concentrations of bile salts, polar lipids, and neutral lipids. For all evaluated parameters, healthy rats were used as a reference. The DAI score, colon length, and histological evaluation of the colon were effective disease indicators in DSS-induced colitis rats, while spleen weight, plasma C-reactive protein, and plasma lipocalin-2 were not. The luminal pH of the colon and bile salt- and neutral lipid concentrations in regions of the small intestine were lower in DSS-induced rats compared to healthy rats. Overall, the colitis model was deemed relevant for investigating ulcerative colitis-specific formulations.

Clinical remission in paired phase two and three studies in inflammatory bowel disease: a systematic review with meta-analysis

Discrepancies in phase two and three studies can result in significant patient and financial burden, as well as the nonapproval of potentially efficacious drugs. We aimed to determine whether this discrepancy exists for clinical trials in inflammatory bowel disease (IBD). Electronic databases (MEDLINE and Embase) and clinical trial repositories were searched from 1 January 1946 to 12 March 2021, for paired phase two and three studies of advanced therapies for Crohn's disease and ulcerative colitis. The primary outcome was to compare clinical remission rates between paired phase two and three studies for Crohn's disease and ulcerative colitis. Multivariable mixed-model meta-analysis was performed to calculate odds ratios (OR) with 95% confidence intervals (CI). The Cochrane risk-of-bias tool was used to grade the risk of bias. Of 2642 studies, 29 were included. Fifteen were phase three, 11 were phase two, one was phase one/two, and two were phase two/three. There were no differences in clinical remission rates between phase two and three studies for Crohn's disease (OR, 1.07; 95% CI, 0.86-1.34; P = 0.54) and ulcerative colitis (OR, 0.81; 95% CI, 0.48-1.36; P = 0.43). Furthermore, there was a lack of any appreciable differences in study characteristics, inclusion criteria and patient demographics among paired phase two and three studies. Most studies were considered low risk of bias. Overall, paired phase two and three studies demonstrate similar clinical remission rates for advanced therapies in IBD. Whether this applies to newer outcomes, such as endoscopic and mucosal healing remains to be determined.

Mise au point de l’utilisation de l’intelligence artificielle dans la prise en charge des maladies inflammatoires chroniques de l’intestin

Complexity of inflammatory bowel diseases (IBD) lies on their management and their biology. Clinics, blood and fecal samples tests, endoscopy and histology are the main tools guiding IBD treatment, but they generate a large amount of data, difficult to analyze by clinicians. Because of its capacity to analyze large number of data, artificial intelligence is currently generating enthusiasm in medicine, and this technology could be used to improve IBD management. In this review, after a short summary on IBD management and artificial intelligence, we will report pragmatic examples of artificial intelligence utilisation in IBD. Lastly, we will discuss the limitations of this technology.

Exploring the Pipeline of Novel Therapies for Inflammatory Bowel Disease; State of the Art Review

Crohn’s disease (CD) and ulcerative colitis (UC), known as inflammatory bowel diseases (IBD), are characterized by chronic inflammation of the gastrointestinal tract. Over the last two decades, numerous medications have been developed and repurposed to induce and maintain remission in IBD patients. Despite the approval of multiple drugs, the major recurring issues continue to be primary non-response and secondary loss of response, as well as short- and long-term adverse events. Most clinical trials show percentages of response under 60%, possibly as a consequence of strict inclusion criteria and definitions of response. That is why these percentages appear to be more optimistic in real-life studies. A therapeutic ceiling has been used as a term to define this invisible bar that has not been crossed by any drug yet. This review highlights novel therapeutic target agents in phases II and III of development, such as sphingosine-1-phosphate receptor modulators, selective Janus kinase inhibitors, anti-interleukins, and other small molecules that are currently under research until 1 January 2023. Emerging treatments for CD and UC that have just received approval or are undergoing phase III clinical trials are also discussed in this review.

Ozanimod-Associated Iatrogenic Kaposi Sarcoma in a Patient With Ulcerative Colitis

Ozanimod is an oral sphingosine-1-phosphate receptor modulator. Although it can be an effective drug for the induction and maintenance of remission in patients with moderately to severely active ulcerative colitis, there have been a few reported cases of various malignancies after exposure to this small molecule. We describe a unique case of biopsy-proven Kaposi sarcoma of the skin and colon in a patient with biologic-resistant ulcerative colitis after treatment with ozanimod for 2 months. Given the potential risk of malignancy associated with this agent, physicians should be aware of this rare adverse event.

The long-term effect of biologics in patients with ulcerative colitis emerging from a large Japanese cohort

To gain a better understanding of the effects of biologics, we evaluated clinical outcomes in patients with moderate to severe exacerbations of ulcerative colitis (UC). This retrospective, multicenter study retrieved the entire clinical courses of UC patients who began treatments between 2004 and 2018. All exacerbations and clinical parameters, including treatment details for exacerbations and both remission and re-exacerbation dates, were identified during the observation period. Two different endpoints, the cumulative incidence rates of surgical resection and re-exacerbation, were evaluated separately in moderate to severe exacerbation events. Among 1401 patients, 1626 exacerbation events were determined according to a partial Mayo score (remission: < 2, mild: 2-4, moderate: 5-7, and severe: > 7). During the observation period, as administration rates of biologics increased, both surgical resection and hospitalization rates decreased, for 959 moderate to severe exacerbation events. We confirmed that biologics significantly reduced the cumulative re-exacerbation rate in moderate to severe exacerbation events during the study period compared with suboptimal therapies (a 0.507-fold decreased risk according to COX regression analysis, P < 0.001). However, they had not enough impact in reducing the cumulative incidence rate of surgical resection in moderate to severe exacerbation events that were corticosteroid-refractory or dependent (a 0.878-fold decreased risk according to COX regression analysis, P = 0.606). Biologics may improve remission duration, but these agents had no significant impact in reducing the risk of surgical resection in moderate to severe active UC.

5'AMP-activated protein kinase: an emerging target of phytochemicals to treat chronic inflammatory diseases

Inflammation is a defensive response of the organism to traumatic, infectious, toxic, ischemic, and autoimmune injury. Inflammatory mediators are released to effectively eliminate the inflammatory trigger and restore homeostasis. However, failure of these processes can lead to chronic inflammatory conditions and diseases such as inflammatory bowel diseases, rheumatoid arthritis, inflammatory lung diseases, atherosclerosis, and neurodegenerative diseases. The cure of chronic inflammatory diseases remains challenging as current therapies have various limitations, such as pronounced side effects, progressive loss of efficacy, and high cost especially for biologics. In this context, phytochemicals (such as alkaloids, flavonoids, lignans, phenolic acids, saponins, terpenoids, and other classes) are considered as an interesting alternative approach. Among the numerous targets of phytochemicals, AMP-activated protein kinase (AMPK) can be considered as an interesting target in the context of inflammation. AMPK regulates inflammatory response by inhibiting inflammatory pathways (NF-κB, JAK/STAT, and MAPK) and regulating several other processes of the inflammatory response (oxidative stress, autophagy, and apoptosis). In this review, we summarize and discuss the studies focusing on phytochemicals that showed beneficial effects by blocking different inflammatory pathways implicating AMPK activation in chronic inflammatory disease models. We also highlight elements to consider when investigating AMPK in the context of phytochemicals.

ST2 and CSF-1 as potential druggable targets of inflammatory bowel diseases: Results from two-sample Mendelian randomization study

Novel druggable targets are warranted for inflammatory bowel disease (IBD) treatment. We aimed to identify novel circulating proteins with causal associations with the risk of IBDs and provide potential therapeutic targets for IBD treatment. We performed a two-sample Mendelian randomization (MR) study to explore the associations of 55 circulating biomarkers on the risk of IBD, Crohn's disease (CD), and ulcerative colitis (UC) by leveraging the summary statistics from large genomewide association studies and protein quantitative trait loci studies. The individual estimate was pooled together by meta-analyses to estimate the causal effects of each outcome. In univariable MR, we identified several circulating proteins showed potential correlation with IBD, UC, and CD. Of note, we observed that a genetically proxied increased level of suppression of tumorigenicity 2 (ST2) was associated with an elevated risk of IBD (odds ratios [ORs] 1.133, 95% confidence interval [CI] 1.091-1.176, p < 0.0001), CD (ORs 1.188, 95% CI 1.103-1.281, p < 0.0001), and UC cohorts (ORs 1.087, 95% CI 1.050-1.125, p < 0.0001). Additionally, we observed a consistent positive correlation between the level of CSF-1 and the increased risk of IBD in individual MR, with statistically significant causal associations in the meta-analyses with ORs equal to 1.217 (IBD, 95% CI 1.115-1.328, p < 0.0001), 1.223 (CD, 95% CI 1.082-1.382, p = 0.0013), and 1.179 (UC, 95% CI 1.055-1.317, p = 0.0037). This study provided evidence for potential casual associations between circulating ST2 and CSF-1 levels, and increased risks of IBD, UC, and CD, implicating potential treatment targets for IBD and subtypes.

Efficacy and Safety of Infliximab Retreatment in Crohn's Disease: A Multicentre, Prospective, Observational Cohort (REGAIN) Study from the GETAID

INTRODUCTION

The objective of this study was to describe the efficacy and safety of infliximab (IFX) reintroduction in Crohn's disease (CD) after stopping for loss of response or intolerance.

METHODS

We conducted a prospective multicenter observational cohort study including adult patients with clinically (CD Activity Index &gt;150) and objectively active luminal CD in whom IFX was reintroduced after at least 6 months of discontinuation. The reasons for the initial discontinuation could be a secondary loss of response or IFX intolerance. The reintroduction schedule included 3 IFX infusions at weeks 0, 4, and 8, after a systematic premedication. The primary end point was the efficacy of IFX retreatment at week 26 defined by a CD Activity Index of &lt;150 in the absence of IFX discontinuation or use of corticosteroids, surgery, or other biologic.

RESULTS

At week 26, 24 patients (35%) among the 69 analyzed reached the primary end point. No significant difference was observed between rates of clinical remission at week 26 in patients with prior LOR (n = 48) and those with IFX intolerance (n = 21) (35% and 33%, P = 0.87, respectively). Thirty-two acute infusion reactions were recorded in 27 patients, leading to withdrawal of IFX in 20 patients. No pharmacokinetic characteristic at baseline but detection of positive anti-drug antibodies at week 4 was predictive of IFX failure or infusion reaction at week 26.

DISCUSSION

In this first prospective cohort study, IFX retreatment was safe and effective in one-third of the patients with CD, regardless the reason of prior discontinuation. Early detection of anti-drug antibodies can predict subsequent IFX reintroduction failure and infusion reactions.

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.

Discovery of novel PDE4 inhibitors targeting the M-pocket from natural mangostanin with improved safety for the treatment of Inflammatory Bowel Diseases

Inflammatory Bowel Diseases (IBDs) are chronic disorders with iterative intestinal mucosal inflammation which remain unmet medical needs. PDE4 inhibitors were reported to be novel anti-IBD agents, but their clinical use was hampered by side effects such as emesis and nausea. Herein, structure-based discovery of natural mangostanin (1) targeting the M-pocket resulted in the novel and potent PDE4 inhibitor 22d (IC₅₀ = 3.5 nM) and favorable physico-chemical properties. X-Ray study revealed that 22d interacted tightly with the M-pocket and maintained the key interactions between PDE4 and roflumilast. Worthy to note that compounds 22d and our previously reported 4e and 18a, originating from mangostanin, all caused no emesis on beagle dogs at the oral dose of 10 mg/kg, confirming the safety superiority of scaffold in mangostanin derivatives over that in positive roflumilast. Finally, administration of 22d (5.0 mg/kg, twice-daily) exhibited comparable anti-IBD effects to the positive control dipyridamole (25.0 mg/kg, twice-daily) in the dextran sulfate sodium (DSS)-induced IBD mice model, indicating its potential as a novel anti-IBD agent.

Introduction of Subcutaneous Infliximab CT-P13 and Vedolizumab in Clinical Practice: A Multi-Stakeholder Position Statement Highlighting the Need for Post-Marketing Studies

BACKGROUND AND AIMS

Although subcutaneous formulations of infliximab CT-P13 and vedolizumab are registered for treating moderate-to-severe inflammatory bowel disease [IBD], many questions on their use remain unanswered. We set up a multi-stakeholder initiative resulting in a position statement.

METHODS

Based on publicly available data, statements on subcutaneous infliximab and vedolizumab were developed and reviewed by 45 Belgian IBD physicians in a three-round modified Delphi process. During a consensus meeting, input from 16 IBD patients, nine IBD nurses and two clinical pharmacologists was provided and statements were further discussed, modified and scored. Statements achieving agreement by at least 70% of the IBD physicians were accepted.

RESULTS

The Delphi process resulted in 79 agreed statements. In patients initiating intravenous therapy, IBD physicians would only consider switching to subcutaneous formulations in patients achieving both clinical and biological response [for Crohn's disease] or both clinical and endoscopic response [for ulcerative colitis]. For patients under maintenance therapy, switching to subcutaneous formulations was only considered in those achieving both clinical and endoscopic response while receiving standard dosing of infliximab or vedolizumab. While awaiting more scientific data, IBD physicians should consider weekly subcutaneous injections or switching back to an intravenous formulation in case of loss of response. Finally, switching to a subcutaneous formulation should always be a shared decision.

CONCLUSIONS

All stakeholders welcomed subcutaneous infliximab and vedolizumab. However, more scientific data are needed to select the right patients and timing for switching to these newer formulations, and to explore the optimal strategy in case of loss of response.

The Role of Tissue-Resident Macrophages in the Development and Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), comprising Crohn’s disease and ulcerative colitis, is a refractory disease with many immune abnormalities and pathologies in the gastrointestinal tract. Because macrophages can distinguish innocuous antigens from potential pathogens to maintain mucosa barrier functions, they are essential cells in the intestinal immune system. With numerous numbers in the intestinal tract, tissue-resident macrophages have a significant effect on the constant regeneration of intestinal epithelial cells and maintaining the immune homeostasis of the intestinal mucosa. They also have a significant influence on IBD through regulating pro-(M1) or anti-inflammatory (M2) phenotype polarization according to different environmental cues. The disequilibrium of the phenotypes and functions of macrophages, disturbed by intracellular or extracellular stimuli, influences the progression of disease. Further investigation of macrophages’ role in the progression of IBD will facilitate deciphering the pathogenesis of disease and exploring novel targets to develop novel medications. In this review, we shed light on the origin and maintenance of intestinal macrophages, as well as the role of macrophages in the occurrence and development of IBD. In addition, we summarize the interaction between gut microbiota and intestinal macrophages, and the role of the macrophage-derived exosome. Furthermore, we discuss the molecular and cellular mechanisms participating in the polarization and functions of gut macrophages, the potential targeted strategies, and current clinical trials for IBD.

Management of Non-response and Loss of Response to Anti-tumor Necrosis Factor Therapy in Inflammatory Bowel Disease

Anti-tumor necrosis factor (anti-TNF) therapy has been successfully used as first-line biologic treatment for moderate-to-severe inflammatory bowel disease (IBD), in both “step-up” and “top-down” approaches, and has become a cornerstone of IBD management. However, in a proportion of patients the effectiveness of anti-TNF therapy is sub-optimal. Either patients do not achieve adequate initial response (primary non-response) or they lose response after initial success (loss of response). Therapeutic drug monitoring determines drug serum concentrations and the presence of anti-drug antibodies (ADAbs) and can help guide treatment optimization to improve patient outcomes. For patients with low drug concentrations who are ADAb-negative or display low levels of ADAbs, dose escalation is recommended. Should response remain unchanged following dose optimization the question whether to switch within class (anti-TNF) or out of class (different mechanism of action) arises. If ADAb levels are high and the patient has previously benefited from anti-TNF therapy, then switching within class is a viable option as ADAbs are molecule specific. Addition of an immunomodulator may lead to a decrease in ADAbs and a regaining of response in a proportion of patients. If a patient does not achieve a robust therapeutic response with an initial anti-TNF despite adequate drug levels, then switching out of class is appropriate. In conjunction with the guidance above, other factors including patient preference, age, comorbidities, disease phenotype, extra-intestinal manifestations, and treatment costs need to be factored into the treatment decision. In this review we discuss current evidence in this field and provide guidance on therapeutic decision-making in clinical situations.

Deep Learning Analysis of Histologic Images from Intestinal Specimen Reveals Adipocyte Shrinkage and Mast Cell Infiltration to Predict Postoperative Crohn Disease

Most patients with Crohn disease (CD), a chronic inflammatory gastrointestinal disease, experience recurrence despite treatment, including surgical resection. However, methods for predicting recurrence remain unclear. This study aimed to predict postoperative recurrence of CD by computational analysis of histopathologic images and to extract histologic characteristics associated with recurrence. A total of 68 patients who underwent surgical resection of the intestine were included in this study and were categorized into two groups according to the presence or absence of postoperative disease recurrence within 2 years after surgery. Recurrence was defined using the CD Activity Index and the Rutgeerts score. Whole-slide images of surgical specimens were analyzed using deep learning model EfficientNet-b5, which achieved a highly accurate prediction of recurrence (area under the curve, 0.995). Moreover, subserosal tissue images with adipose cells enabled highly accurate prediction. Adipose cell morphology showed significant between-group differences in adipose cell size, cell-to-cell distance, and cell flattening values. These findings suggest that adipocyte shrinkage is an important histologic characteristic associated with recurrence. Moreover, there was a significant between-group difference in the degree of mast cell infiltration in the subserosa. These findings show the importance of mesenteric adipose tissue in patient prognosis and CD pathophysiology. These findings also suggest that deep learning-based artificial intelligence enables the extraction of meaningful histologic features.

Biologics in Pediatric Inflammatory Bowel Disease

Inflammatory bowel diseases (IBD) consist of Crohn's disease and ulcerative colitis. These are conditions that, although managed by pediatric gastroenterologists, are encountered frequently by the general pediatrician. The purpose of this article is to review the use of targeted antibody treatments, also known as biologics, in the treatment of pediatric IBD as well as complications and adverse effects for the pediatrician to consider when caring for a patient with IBD who is taking biologics. [Pediatr Ann. 2022;51(2):e77-e81.].

Anti-HBV drug entecavir ameliorates DSS-induced colitis through PD-L1 induction

PD-L1-mediated signaling is one of the major processes that regulate local inflammatory responses in the gut. To date, protective effects against colitis through direct Fc-fused PD-L1 administration or indirect PD-L1 induction by probiotics have been reported. We have previously shown that the anti-HBV drug entecavir (ETV) induces PD-L1 expression in human hepatocytes. In the present study, we investigated whether ETV induces PD-L1 expression in intestinal cells and provides a protective effect against DSS-induced colitis. ETV induced PD-L1 expression in epithelial cells, rather than T and B cells, improving the symptoms of colitis. In the mechanistic analysis, Th17 cell differentiation was inhibited and B cell infiltration into the lamina propria was reduced. In addition, PD-L1 expression was positively correlated with Foxp3 or CSF1-R. In conclusion, ETV upregulated PD-L1 expression in epithelial cells and ameliorated inflammation in DSS-induced colitis. These results suggest that ETV may be a potential therapeutic agent as a PD-L1 enhancer for the treatment of human IBD.

Diosmetin attenuate experimental ulcerative colitis in rats via suppression of NF-κB, TNF-α and IL-6 signalling pathways correlated with down-regulation of apoptotic events

Introduction

Ulcerative colitis (UC) is a chronic inflammation of colon in which the innermost tissue of colon and rectum develops deep-rooted inflammation. Diosmetin is the aglycone of the flavonoid glycoside diosmin, commonly found in citrus fruits. Therapeutically diosmetin is indicated to demonstrate anticancer, antimicrobial, antioxidant, oestrogenic and anti-inflammatory activity.

Methods

In this research, we studied the action of diosmetin on TNBS (2,4,6-trinitrobenzene sulfonic acid)-induced UC in rats. Male Wister rats were anesthetised with pentobarbital and TNBS introduced by performing an enema. Diosmetin treatment was provided through oral gavage for the next 28 days. Animals were sacrificed on the 29th day and colon tissues were collected for further examinations.

Results

Diosmetin treatment decreased colonic ulceration dramatically and decreased the percentage of inflammation in the colonic mucosa. Depletion of the TNBS assisted of superoxide dismutase and catalase was substantially restricted, while lipid peroxidation was recorded in the colonic tissue as malondialdehyde content was also decreased. After treatment with diosmetin, the occurrence of TNF-α, IL-6and NF-κB was considerably lowered and the number of apoptotic cells observed was significantly reduced.

Conclusion

Taken together, these observations demonstrated the potential of diosmetin against ulcer formation and development.

A network pharmacology approach to reveal the pharmacological targets and biological mechanism of compound kushen injection for treating pancreatic cancer based on WGCNA and in vitro experiment validation

BACKGROUND

Compound kushen injection (CKI), a Chinese patent drug, is widely used in the treatment of various cancers, especially neoplasms of the digestive system. However, the underlying mechanism of CKI in pancreatic cancer (PC) treatment has not been totally elucidated.

METHODS

Here, to overcome the limitation of conventional network pharmacology methods with a weak combination with clinical information, this study proposes a network pharmacology approach of integrated bioinformatics that applies a weighted gene co-expression network analysis (WGCNA) to conventional network pharmacology, and then integrates molecular docking technology and biological experiments to verify the results of this network pharmacology analysis.

RESULTS

The WGCNA analysis revealed 2 gene modules closely associated with classification, staging and survival status of PC. Further CytoHubba analysis revealed 10 hub genes (NCAPG, BUB1, CDK1, TPX2, DLGAP5, INAVA, MST1R, TMPRSS4, TMEM92 and SFN) associated with the development of PC, and survival analysis found 5 genes (TSPOAP1, ADGRG6, GPR87, FAM111B and MMP28) associated with the prognosis and survival of PC. By integrating these results into the conventional network pharmacology study of CKI treating PC, we found that the mechanism of CKI for PC treatment was related to cell cycle, JAK-STAT, ErbB, PI3K-Akt and mTOR signalling pathways. Finally, we found that CDK1, JAK1, EGFR, MAPK1 and MAPK3 served as core genes regulated by CKI in PC treatment, and were further verified by molecular docking, cell proliferation assay, RT-qPCR and western blot analysis.

CONCLUSIONS

Overall, this study suggests that the optimized network pharmacology approach is suitable to explore the molecular mechanism of CKI in the treatment of PC, which provides a reference for further investigating biomarkers for diagnosis and prognosis of PC and even the clinical rational application of CKI.

Target-Based Small Molecule Drug Discovery Towards Novel Therapeutics for Inflammatory Bowel Diseases

Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), is a class of severe and chronic diseases of the gastrointestinal (GI) tract with recurrent symptoms and significant morbidity. Long-term persistence of chronic inflammation in IBD is a major contributing factor to neoplastic transformation and the development of colitis-associated colorectal cancer. Conversely, persistence of transmural inflammation in CD is associated with formation of fibrosing strictures, resulting in substantial morbidity. The recent introduction of biological response modifiers as IBD therapies, such as antibodies neutralizing tumor necrosis factor (TNF)-α, have replaced nonselective anti-inflammatory corticosteroids in disease management. However, a large proportion (~40%) of patients with the treatment of anti-TNF-α antibodies are discontinued or withdrawn from therapy because of (1) primary nonresponse, (2) secondary loss of response, (3) opportunistic infection, or (4) onset of cancer. Therefore, the development of novel and effective therapeutics targeting specific signaling pathways in the pathogenesis of IBD is urgently needed. In this comprehensive review, we summarize the recent advances in drug discovery of new small molecules in preclinical or clinical development for treating IBD that target biologically relevant pathways in mucosal inflammation. These include intracellular enzymes (Janus kinases, receptor interacting protein, phosphodiesterase 4, IκB kinase), integrins, G protein-coupled receptors (S1P, CCR9, CXCR4, CB2) and inflammasome mediators (NLRP3), etc. We will also discuss emerging evidence of a distinct mechanism of action, bromodomain-containing protein 4, an epigenetic regulator of pathways involved in the activation, communication, and trafficking of immune cells. We highlight their chemotypes, mode of actions, structure-activity relationships, characterizations, and their in vitro/in vivo activities and therapeutic potential. The perspectives on the relevant challenges, new opportunities, and future directions in this field are also discussed.

Research-Based Product Innovation to Address Critical Unmet Needs of Patients with Inflammatory Bowel Diseases

Despite progress in recent decades, patients with inflammatory bowel diseases face many critical unmet needs, demonstrating the limitations of available treatment options. Addressing these unmet needs will require interventions targeting multiple aspects of inflammatory bowel disease pathology, including disease drivers that are not targeted by available therapies. The vast majority of late-stage investigational therapies also focus primarily on a narrow range of fundamental mechanisms. Thus, there is a pressing need to advance to clinical stage differentiated investigational therapies directly targeting a broader range of key mechanistic drivers of inflammatory bowel diseases. In addition, innovations are critically needed to enable treatments to be tailored to the specific underlying abnormal biological pathways of patients; interventions with improved safety profiles; biomarkers to develop prognostic, predictive, and monitoring tests; novel devices for nonpharmacological approaches such as minimally invasive monitoring; and digital health technologies. To address these needs, the Crohn's & Colitis Foundation launched IBD Ventures, a venture philanthropy-funding mechanism, and IBD Innovate®, an innovative, product-focused scientific conference. This special IBD Innovate® supplement is a collection of articles reflecting the diverse and exciting research and development that is currently ongoing in the inflammatory bowel disease field to deliver innovative and differentiated products addressing critical unmet needs of patients. Here, we highlight the pipeline of new product opportunities currently advancing at the preclinical and early clinical development stages. We categorize and describe novel and differentiated potential product opportunities based on their potential to address the following critical unmet patient needs: (1) biomarkers for prognosis of disease course and prediction/monitoring of treatment response; (2) restoration of eubiosis; (3) restoration of barrier function and mucosal healing; (4) more effective and safer anti-inflammatories; (5) neuromodulatory and behavioral therapies; (6) management of disease complications; and (7) targeted drug delivery.

A Novel OGR1 (GPR68) Inhibitor Attenuates Inflammation in Murine Models of Colitis

Background and Aims

Local extracellular acidification is associated with several conditions, such as ischemia, cancer, metabolic disease, respiratory diseases, and inflammatory bowel disease (IBD). Several recent studies reported a link between IBD and a family of pH-sensing G protein-coupled receptors. Our previous studies point to an essential role for OGR1 (GPR68) in the modulation of intestinal inflammation and fibrosis. In the current study, we evaluated the effects of a novel OGR1 inhibitor in murine models of colitis.

Methods

The effects of a novel small-molecule OGR1 inhibitor were assessed in the acute and chronic dextran sulfate sodium (DSS) murine models of colitis. Macroscopic disease indicators of intestinal inflammation were evaluated, and epithelial damage and immune cell infiltration and proliferation were assessed by immunohistochemistry.

Results

The OGR1 inhibitor ameliorated clinical parameters in acute and chronic DSS-induced colitis. In mice treated with the OGR1 inhibitor, endoscopy showed no thickening and normal vascularity, while fibrin was not detected. Histopathological findings revealed a decrease in severity of colonic inflammation in the OGR1 inhibitor group when compared to vehicle-DSS controls. In OGR1 inhibitor-treated mice, staining for the macrophage marker F4/80 and cellular proliferation marker Ki-67 revealed a reduction of infiltrating macrophages and slightly enhanced cell proliferation, respectively. This was accompanied by a reduction in pro-inflammatory cytokines, TNF and IL-6, and the fibrosis marker TGF-β1.

Conclusion

This is the first report providing evidence that a pharmacological inhibition of OGR1 has a therapeutic effect in murine colitis models. Our data suggest that targeting proton-sensing OGR1 using specific small-molecule inhibitors may be a novel therapeutic approach for the treatment of IBD.

Serum Interleukin (IL)-23 and IL-17 Profile in Inflammatory Bowel Disease (IBD) Patients Could Differentiate between Severe and Non-Severe Disease

Interleukin (IL)-17 and IL-23 are crucial for mediating gut mucosal inflammation in inflammatory bowel disease (IBD), which has led to new therapeutic strategies. We assessed the relevancy of IL-17 and IL-23 serum levels as potential biomarkers towards severe IBD discrimination and disease-related complications. Sixty-two patients diagnosed with Crohn's disease (CD) and ulcerative colitis (UC) were included. Serum IL-17 and IL-23 were measured by sandwich enzyme-linked immunosorbent assays (ELISA). IL-23 and fecal calprotectin (FCal) were significantly higher in severe CD (p < 0.001) and UC (p < 0.001 and p = 0.001, respectively), compared to mild or moderate. Elevated C-reactive protein (CRP) was correlated with severe disease only in CD (p = 0.008), whereas for UC, disease severity was associated with increased IL-17 values (p < 0.001). Diagnostic role of IL-23 was superior to FCal in discriminating between severe and mild to moderate CD (p < 0.001). IL-23 levels were also significantly higher in CD patients with intestinal complications (p = 0.04). Both IL-17 and IL-23 correlate with IBD severity, and IL-23 might be a promising novel biomarker for severe CD. Identifying the dominant IL pathway involved in IBD severity could serve as guidance for clinical decision-making on biologic therapy.

Safety and efficacy of combining biologics or small molecules for inflammatory bowel disease or immune-mediated inflammatory diseases: A European retrospective observational study

BACKGROUND AND AIMS

Few data are available regarding the combination of biologics or small molecules in inflammatory bowel disease (IBD) patients. We report safety and efficacy of such combinations through a retrospective multicentre series.

METHODS

Combination therapy was defined as the concomitant use of two biologics or one biologic with a small molecule. Patient demographics, disease characteristics and types of combinations were recorded. Safety was evaluated according to the occurrence of serious infection, opportunistic infection, hospitalisation, life-threatening event, worsening of IBD or immune-mediated inflammatory diseases (IMID), cancer and death. Efficacy was evaluated as the physician global assessment of the combination and comparison of clinical/endoscopic scores of IBD/IMID activity prior and during combination.

RESULTS

A total of 104 combinations were collected in 98 patients. Concomitant IMID were present in 41 patients. Reasons for starting combination therapy were active IBD (67%), active IMID or extra-intestinal manifestations (EIM) (22%), both (10%) and unclassified in 1. Median duration of combination was 8 months (interquartile range 5-16). During 122 patient-years of follow-up, 42 significant adverse events were observed, mostly related to uncontrolled IBD. There were 10 significant infections, 1 skin cancer and no death. IBD disease activity was clinically improved in 70% and IMID/EIM activity in 81% of the patients. Overall, combination was continued in 55% of the patients.

CONCLUSIONS

Combination of biologics and small molecules in patients with IBD and IMID/EIM seems to be a promising therapeutic strategy but is also associated with a risk of opportunistic infections or infections leading to hospitalisation in 10%.

Oncostatin M Is a Biomarker of Diagnosis, Worse Disease Prognosis, and Therapeutic Nonresponse in Inflammatory Bowel Disease

BACKGROUND

Oncostatin M (OSM) has been implicated in the pathogenesis of inflammatory bowel disease (IBD) and as a marker for nonresponsiveness to anti-tumor necrosis factor (TNF) therapy. We further unraveled the potential of OSM and related receptors as markers of diagnosis, prognosis, and therapy response in IBD.

METHODS

We collected inflamed mucosal biopsies and serum from patients with Crohn disease (CD) and with ulcerative colitis: (1) newly diagnosed patients who were treatment-naïve, (2) patients initiating anti-TNF or (3) vedolizumab therapy, (4) postoperative patients with CD, and (5) multiple-affected families with IBD including unaffected first-degree relatives (FDRs). We measured the gene expression of mucosal OSM and its receptors OSMR/LIFR and co-receptor IL6ST, and the protein expression of serum OSM. Statistical significance was defined as P < 0.05.

RESULTS

Newly diagnosed patients showed significantly increased mucosal OSM/OSMR compared with control patients, with the highest enrichment for OSM (fold change [FC] >17.9). Likewise, ileal OSM/OSMR were significantly upregulated in postoperative recurrent CD. Serum OSM was increased in newly diagnosed patients and postoperative patients with recurrent CD (FC ≥ 2.6). In families with IBD, higher serum levels were observed in FDRs than in control families (FC = 2.2). Furthermore, elevated colonic OSM/OSMR (but not serum OSM) were associated with the early need for biologic therapy (FC ≥ 1.9), and higher OSM was also predictive of primary nonresponse to both anti-TNF and vedolizumab therapy (FC ≥ 2.4). Immunohistochemistry highlighted mucosal OSM expression in macrophages.

CONCLUSIONS

We found that OSM is a diagnostic biomarker in the tissue and serum not only of newly diagnosed patients with IBD and postoperative patients with recurrent CD but also of their FDRs. Higher colonic OSM levels are furthermore associated with poor prognosis and with primary nonresponse to biologic therapies. Therefore, OSM could guide clinical decision-making.

Centipeda minima Extract Attenuates Dextran Sodium Sulfate-Induced Acute Colitis in Mice by Inhibiting Macrophage Activation and Monocyte Chemotaxis

Inflammatory bowel disease (IBD) is an idiopathic inflammatory disease affecting the gastrointestinal tract. IBD is characterized by courses of relapse and remission, and remains incurable. Although multiple factors are related to the pathogenesis of IBD, disruption of intestinal mucosa homeostasis has been proposed to be a major contributor to IBD, and abnormal activation of immune cells is key for initiation of the inflammatory response. Macrophages are the most abundant immune cells in the intestine. Once activated, they are responsible for secretion of pro-inflammatory cytokines and chemokines to attract circulating monocytes to inflammatory sites, exacerbating the inflammatory response, and leading to tissue damage. Therefore, the suppression of activated macrophages, cytokine/chemokine production, and subsequent monocyte chemotaxis possesses great potential for the treatment of IBD. In our study, we have demonstrated the inhibitory effect of Centipeda minima total extract (CME) on the activation of NF-κB, STAT3, and MAPK signaling in LPS-stimulated RAW264.7 macrophages. In addition, we identified the significant suppressive effect of CME on CCL8 expression in activated macrophages, which potentially contributed to inhibition of monocyte chemotaxis. In the DSS-induced acute colitis mouse model, we have demonstrated the suppressive effect of CME on intestinal macrophage infiltration and its ameliorative effect in IBD. Altogether, we have provided evidence of the therapeutic effect of CME in IBD and the potential of CME for the treatment of IBD.

Real-life burden of adverse reactions to biological therapy in inflammatory bowel disease: a single-centre prospective case series

Background/aim

Biologics represent a key therapeutic option in inflammatory bowel disease (IBD), but are associated with several side effects. Post-marketing surveillance, through a spontaneous adverse drug reactions (ADRs) monitoring system, is essential to assess the safety profile of biologics. The aim of the study was to prospectively evaluate the occurrence of ADRs in IBD patients treated with biologics from a single centre in Southern Italy.

Methods

Data from patients with Crohn's Disease (CD) and Ulcerative Colitis (UC) who underwent biological therapy were prospectively collected. ADRs were classified according to the Medical Dictionary for Regulatory Activities (MedDRA®).

Results

Overall, 68 (54% male, 68% with UC and 32% with CD) biologic-naïve IBD patients underwent biological therapy. Mean follow-up was 11.7 ± 6.2 months. As a results of switches, for 68 patients we obtained 96 biologic prescriptions. Overall, 45 ADRs occurred in 36 (53%) patients, distributed as follows (ADRs/prescriptions): 19/37 with IFX-Remicade, 5/12 with IFX-Remsima, 8/9 with GOL, 11/26 with ADA, and 2/12 with VDZ. Mild ADRs were 29 (64%), moderate 15 (34%) and 1 (2%) severe. General disorders and administration related reactions were the most frequent ADRs (35%), followed by skin and subcutaneous tissue disorders (20%), infections (15%), musculoskeletal (11%), respiratory (6%) blood (4%), gastrointestinal (4%), and vascular disorders (2%). In 9 cases (20%) the ADRs resulted in definitive discontinuation of biologic therapy.

Conclusion

In a prospective cohort of IBD patients, more than half experienced ADRs during biologic therapy. General disorders and administration related reactions were the most common ADRs, while infections were less common and rarely led to discontinuation of therapy. Findings underline the importance of surveillance in management of IBD patients during biologic therapy and implementing safety protocols with data from real-life settings.

Biological Treatments in Inflammatory Bowel Disease: A Complex Mix of Mechanisms and Actions

Inflammatory bowel disease (IBD) is a chronic disease that requires lifelong medication and whose incidence is increasing over the world. There is currently no cure for IBD, and the current therapeutic objective is to control the inflammatory process. Approximately one third of treated patients do not respond to treatment and refractoriness to treatment is common. Therefore, pharmacological treatments, such as monoclonal antibodies, are urgently needed, and new treatment guidelines are regularly published. Due to the extremely important current role of biologics in the therapy of IBD, herein we have briefly reviewed the main biological treatments currently available. In addition, we have focused on the mechanisms of action of the most relevant groups of biological agents in IBD therapy, which are not completely clear but are undoubtfully important for understanding both their therapeutic efficacy and the adverse side effects they may have. Further studies are necessary to better understand the action mechanism of these drugs, which will in turn help us to understand how to improve their efficacy and safety. These studies will hopefully pave the path for a personalized medicine.

Phase 1 study on the safety and efficacy of E6011, antifractalkine antibody, in patients with Crohn's disease

BACKGROUND AND AIM

E6011 is a humanized monoclonal antibody targeting fractalkine (FKN), a CX3C chemokine, which regulates leukocyte trafficking during inflammation. We evaluated the safety and pharmacokinetic profile of E6011 in patients with Crohn's disease (CD) and also performed preliminary pharmacodynamic (PD) and efficacy assessments.

METHODS

This study included a 12-week multiple ascending dose (MAD) phase (2, 5, 10, and 15 mg/kg intravenously every 2 weeks, n = 6, 8, 7, and 7, respectively) and a 40-week Extension phase (n = 12) at the same dose as the MAD phase. Serum E6011, serum total FKN (free soluble FKN and E6011-FKN complex) as a PD marker and CD activity index were evaluated. The primary outcome was safety assessment in the MAD phase.

RESULTS

Twenty-seven (96%) of 28 patients had previously been treated with anti-tumor necrosis factor α agents. During the MAD phase, adverse events (AEs) occurred in 18 (64%). The most common AE was nasopharyngitis (five patients, 18%). No severe AEs occurred. Serious AEs occurred in three patients, progression of CD in two, and anemia in one. Serum E6011 concentrations increased dose-dependently after infusion and reached a plateau around 4-6 weeks. Serum total FKN rose simultaneously. Five (18%) patients developed anti-E6011 antibodies during the study. Overall, clinical response and clinical remission were observed at Week 12 in 40% (10/25) and 16% (4/25) of active CD patients, respectively.

CONCLUSION

E6011 was well-tolerated and might be effective in CD patients. These findings need to be clarified in a randomized controlled study.

Breaking the therapeutic ceiling in drug development in ulcerative colitis

Increased knowledge of the intricate pathogenesis of ulcerative colitis has triggered an advance in drug development during the past two decades, resulting in the advent of several biological agents and small-molecule therapies. Although the increase in therapeutic options is positive, remission rates of patients with ulcerative colitis given new therapeutic agents in induction trials remain at a modest 20-30%, seemingly facing a so-called therapeutic ceiling. This therapeutic ceiling requires a critical appraisal and highlights the need for alternative strategies for drug development. In this Review, we objectively itemise the boundaries of therapeutic efficacy in ulcerative colitis, provide possible explanations for the shortcomings of current strategies, and propose solutions to achieve better therapeutic outcomes in ulcerative colitis.

TL1A: A New Potential Target in the Treatment of Inflammatory Bowel Disease

Inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), are chronic inflammatory diseases of the gastrointestinal tract. In the last few years, the development of biological agents targeting cytokines and receptors involved in IBD pathogenesis has led to better outcomes and has improved the course of the disease. Despite their effectiveness, drugs such as tumor necrosis factor (TNF) inhibitors, anti-Interleukin-12/23 and anti-integrins, do not induce a response in about one-third of patients, and 40% of patients lose response over time. Therefore, more efficient therapies are required. Recent studies showed that TL1A (Tumor necrosis factor-like cytokine 1A) acts as a regulator of mucosal immunity and participates in immunological pathways involved in the IBD pathogenesis. In this review article, we analyze the role of TL1A as a new potential target therapy in IBD patients.