Breaking Through the Therapeutic Ceiling: What Will It Take?

An evaluation of mirikizumab for the treatment of ulcerative colitis

INTRODUCTION

Treatment of ulcerative colitis (UC) aims to reduce symptoms and complications by decreasing intestinal inflammation. A proportion of patients do not respond to, do not tolerate, or are inappropriate candidates for current therapies. Interleukin (IL)-23 is a therapeutic target and mirikizumabis the first p19-targeted IL-23 antibody approved for the treatment of moderately to severely active UC.

AREAS COVERED

This review summarizes the pro-inflammatory effects of IL-23 and outlines the pharmacokinetics of mirikizumab. It provides a synopsis of the available phase II and phase III evidence for the efficacy and safety of mirikizumab in UC.

EXPERT OPINION

The mirikizumab clinical development program demonstrated its superiority over placebo and its favorable safety profile in the treatment of UC. Its positioning in therapeutic algorithms remains to be fully understood but mirikizumab has proven efficacy in both advanced therapy (AT)-naïve and AT-experienced patients. The inclusion in the license of extended induction for non-responders as well as rescue intravenous dosing allows for flexibility in patient with limited primary response and secondary loss of response.

Comparison of ustekinumab, infliximab and combination therapy in moderately to severely active ulcerative colitis - a study protocol of a randomized, multicenter, head-to-head COMBO-UC trial

Background

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with a complex etiology that affects the large intestine. Characterized by chronic, bloody diarrhea, UC can lead to severe complications, including an increased risk of colorectal cancer. Despite advancements in conservative treatment, including biologics like anti-TNF agents and ustekinumab (UST), many patients do not achieve full remission. Dual targeted therapy (DTT) combining infliximab (IFX) and UST is a promising approach to improve treatment outcomes.

Methods

This prospective, randomized, multicenter, head-to-head controlled trial will evaluate the efficacy and safety of UST, IFX, and combination therapy (UST + IFX) in 172 patients with moderate to severe active UC across eight gastroenterology centers in Poland. The study includes a 14-16 week remission induction period followed by a 52-week maintenance phase. Patients will be randomly assigned to one of three treatment arms: IFX monotherapy, UST monotherapy, or IFX + UST combination therapy. Primary endpoint is clinical and endoscopic remission post-induction. Secondary endpoints include clinical response, biochemical remission, histological remission, and quality of life assessments using the Inflammatory Bowel Diseases Questionnaire and 36-Item Short Form Survey. Safety will be monitored through adverse event and serious adverse event reporting.

Discussion

This trial aims to determine whether combining IFX and UST can achieve higher remission rates and better long-term outcomes compared to monotherapy. The results could provide crucial insights into the optimal use of biologic agents in UC treatment, potentially establishing DTT as a standard therapy. The study's design, including extensive follow-up and robust endpoint measures, will contribute to understanding the therapeutic potential and safety profile of this combination therapy.

Integrating multi-omics to unravel host-microbiome interactions in inflammatory bowel disease

The gut microbiome is crucial for nutrient metabolism, immune regulation, and intestinal homeostasis with changes in its composition linked to complex diseases like inflammatory bowel disease (IBD). Although the precise host-microbial mechanisms in disease pathogenesis remain unclear, high-throughput sequencing have opened new ways to unravel the role of interspecies interactions in IBD. Systems biology-a holistic computational framework for modeling complex biological systems-is critical for leveraging multi-omics datasets to identify disease mechanisms. This review highlights the significance of multi-omics data in IBD research and provides an overview of state-of-the-art systems biology resources and computational tools for data integration. We explore gaps, challenges, and future directions in the research field aiming to uncover novel biomarkers and therapeutic targets, ultimately advancing personalized treatment strategies. While focusing on IBD, the proposed approaches are applicable for other complex diseases, like cancer, and neurodegenerative diseases, where the microbiome has also been implicated.

Blocking GPR15 Counteracts Integrin-dependent T Cell Gut Homing in Vivo

BACKGROUND AND AIMS

The G protein coupled receptor GPR15 is expressed on and functionally important for T cells homing to the large intestine. However, the precise mechanisms by which GPR15 controls gut homing have been unclear. Thus, we aimed to elucidate these mechanisms as well as to explore the potential of targeting GPR15 for interfering with T cell recruitment to the colon in inflammatory bowel disease [IBD].

METHODS

We used dynamic adhesion and transmigration assays, as well as a humanised in vivo model of intestinal cell trafficking, to study GPR15-dependent effects on gut homing. Moreover, we analysed GPR15 and integrin expression in patients with and without IBD, cross-sectionally and longitudinally.

RESULTS

GPR15 controlled T cell adhesion to MAdCAM-1 and VCAM-1 upstream of α4β7 and α4β1 integrin, respectively. Consistently, high co-expression of these integrins with GPR15 was found on T cells from patients with IBD, and GPR15 also promoted T cell recruitment to the colon in humanised mice. Anti-GPR15 antibodies effectively blocked T cell gut homing in vitro and in vivo. In vitro data, as well as observations in a cohort of patients treated with vedolizumab, suggest that this might be more effective than inhibiting α4β7.

CONCLUSIONS

GPR15 seems to have a broad, but organ-selective, impact on T cell trafficking and is therefore a promising target for future therapy of IBD. Further studies are needed.

Nationwide Real-World Exclusive Enteral Nutrition Practice Over Time: Persistence of Use as Induction for Pediatric Crohn's Disease and Emerging Combination Strategy With Biologics

BACKGROUND

Exclusive enteral nutrition (EEN) is the recommended first-line induction treatment in pediatric patients with active luminal Crohn's disease (CD). We aimed to provide a nationwide overview of evolving EEN practices during an era of increasing biologic use.

METHODS

We analyzed a prospectively identified nationwide cohort of newly diagnosed pediatric patients with CD in Scotland between January 1, 2015, and June 30, 2022. Patients who received EEN for any indication were divided into 6-monthly epochs and examined over time. Differences during the COVID-19 pandemic (March 16, 2020, to July 19, 2021) were examined. Data were retrospectively collected from electronic medical records: demographics, anthropometrics, concomitant treatments, aspects of EEN administration, and remission/response rates. Descriptive statistics and linear regression were used for analyses.

RESULTS

A total of 649 patients with CD were identified (63% male; median age 12.6 [interquartile range, 10.8-14.8] years); 497 (77%) of 649 received EEN as postdiagnosis induction therapy with a median course length of 7.7 (interquartile range, 5.9-8.0) weeks. Including repeat courses, 547 EEN courses were examined. An increasing incidence of CD was observed over time with no significant changes in EEN usage, remission or response rates, nasogastric tube usage, or course completion (all P > .05). Increasing use of EEN combined with biologics (combination induction) as first-line induction was observed over time (P < .001). Considering COVID-19, lower rates of EEN usage were observed (P = .008) with no differences in remission, oral administration, and course completion rates (all P > .05).

CONCLUSIONS

Over the past 7.5 years, except during the COVID-19 pandemic, EEN usage rates have not changed despite an increase in biologic use, although combination induction is an emerging trend.

Mitochondrial function and gastrointestinal diseases

Mitochondria are dynamic organelles that function in cellular energy metabolism, intracellular and extracellular signalling, cellular fate and stress responses. Mitochondria of the intestinal epithelium, the cellular interface between self and enteric microbiota, have emerged as crucial in intestinal health. Mitochondrial dysfunction occurs in gastrointestinal diseases, including inflammatory bowel diseases and colorectal cancer. In this Review, we provide an overview of the current understanding of intestinal epithelial cell mitochondrial metabolism, function and signalling to affect tissue homeostasis, including gut microbiota composition. We also discuss mitochondrial-targeted therapeutics for inflammatory bowel diseases and colorectal cancer and the evolving concept of mitochondrial impairment as a consequence versus initiator of the disease.

Artificial intelligence and endo-histo-omics: new dimensions of precision endoscopy and histology in inflammatory bowel disease

Integrating artificial intelligence into inflammatory bowel disease (IBD) has the potential to revolutionise clinical practice and research. Artificial intelligence harnesses advanced algorithms to deliver accurate assessments of IBD endoscopy and histology, offering precise evaluations of disease activity, standardised scoring, and outcome prediction. Furthermore, artificial intelligence offers the potential for a holistic endo-histo-omics approach by interlacing and harmonising endoscopy, histology, and omics data towards precision medicine. The emerging applications of artificial intelligence could pave the way for personalised medicine in IBD, offering patient stratification for the most beneficial therapy with minimal risk. Although artificial intelligence holds promise, challenges remain, including data quality, standardisation, reproducibility, scarcity of randomised controlled trials, clinical implementation, ethical concerns, legal liability, and regulatory issues. The development of standardised guidelines and interdisciplinary collaboration, including policy makers and regulatory agencies, is crucial for addressing these challenges and advancing artificial intelligence in IBD clinical practice and trials.

Intercellular interaction between FAP+ fibroblasts and CD150+ inflammatory monocytes mediates fibrostenosis in Crohn's disease

Crohn's disease (CD) is marked by recurring intestinal inflammation and tissue injury, often resulting in fibrostenosis and bowel obstruction, necessitating surgical intervention with high recurrence rates. To elucidate the mechanisms underlying fibrostenosis in CD, we analyzed the transcriptome of cells isolated from the transmural ileum of patients with CD, including a trio of lesions from each patient: non-affected, inflamed, and stenotic ileum samples, and compared them with samples from patients without CD. Our computational analysis revealed that profibrotic signals from a subset of monocyte-derived cells expressing CD150 induced a disease-specific fibroblast population, resulting in chronic inflammation and tissue fibrosis. The transcription factor TWIST1 was identified as a key modulator of fibroblast activation and extracellular matrix (ECM) deposition. Genetic and pharmacological inhibition of TWIST1 prevents fibroblast activation, reducing ECM production and collagen deposition. Our findings suggest that the myeloid-stromal axis may offer a promising therapeutic target to prevent fibrostenosis in CD.

Cellular immunotherapies and immune cell depleting therapies in inflammatory bowel diseases: the next magic bullet?

Despite significant advances in biologic and small molecule treatments and the emergence of combination therapies to treat inflammatory bowel diseases (IBD) a large unmet need remains to control intestinal inflammation. New approaches targeting several pathways simultaneously with a favorable safety profile and agents that trigger anti-inflammatory pathways to drive durable resolution of inflammation are needed. This article discusses novel cellular immunotherapies and immune cell depleting therapies in IBD, including CAR-T cell approaches, Tr1 and T regulatory (Treg) cells and cell depleting antibodies such as rosnilimab. These novel approaches have the potential to overcome current therapeutic limitations in the treatment of IBD.

The Future of Clinical Trials in Inflammatory Bowel Disease

The medical management of inflammatory bowel disease (IBD) has been transformed over the past few decades by the approval of multiple classes of advanced therapies and the integration of more targeted treatment strategies for Crohn's disease and ulcerative colitis. These changes have been driven by an increasing number of pivotal randomized controlled trials, which have grown in size and complexity over time. Several landmark studies that are anticipated to change current IBD management paradigms have recently been completed or are on-going, including the first head-to-head biologic trials, advanced combination treatment trials, therapeutic strategy and treatment target trials, and multiple phase 3 registrational programs of novel compounds. Despite these advances, the future of IBD trials also faces major challenges with respect to cost, feasibility, and recruitment. Accordingly, innovative methods for early and late phase randomized controlled trials must be adopted. In this review, we provide a comprehensive overview of the evolution of modern IBD trials, discuss methods for improving trial efficiency in early and late phase development, and provide insights into the interpretation and implications of these data for clinical care.

Proportion of inflammatory bowel diseases patients with suboptimal disease control in daily clinical practice-Real-world evidence from the inflammatory bowel diseases-podcast study

BACKGROUND

Crohn's disease and ulcerative colitis (UC) are inflammatory bowel diseases (IBD) characterized by a progressive nature of the disease resulting in subsequent intestinal damage, limited efficacy of current treatments and suboptimal disease management and a significant burden for patients.

OBJECTIVES

The IBD-PODCAST study aims to estimate the proportion of Crohn's disease and UC patients with suboptimal disease control (SDC) in a real-world setting.

METHODS

A non-interventional and cross-sectional study was conducted across 103 sites in 10 countries (Austria, Belgium, Canada, Germany, Greece, Italy, Portugal, Spain, Turkey, and UK). Criteria for SDC were based on STRIDE-II criteria and adapted by an expert panel.

RESULTS

2185 patients (Crohn's disease: n = 1,108, UC: n = 1077) with a mean (SD) age of 44.0 (14.8) years and mean (SD) disease duration of 12.4 (9.2) years were included (52.2% male). Ileal involvement was present in 39.1% of Crohn's disease patients, 35.3% of UC patients had extensive colitis. 77.3% of Crohn's disease and 65.3% of UC patients were on targeted immunomodulators and, according to STRIDE-II-based treatment phases, 85.6% of Crohn's disease and 85.4% of UC patients were assigned to the long-term treatment phase. SDC was detected in 52.2% of Crohn's disease and 44.3% of UC patients predominantly due to impaired quality of life (QoL), clinically significant extraintestinal manifestations, steroid overuse, signs of active inflammation in UC and Crohn's disease, and active fistulas in Crohn's disease. More than one criterion was seen in 37% of patients with SDC. Opportunities for on-label treatment optimization were observed in 49% of Crohn's disease and 61% of UC patients on advanced therapy.

CONCLUSION

The high percentage of SDC in this global, real-world cohort suggests a large disease burden and high unmet medical need in IBD patients. Future analysis should focus on monitoring and responding to SDC in this cohort and on patients' QoL.

A practical guide to combination advanced therapy in inflammatory bowel disease

PURPOSE OF REVIEW

To provide an overview of the current literature regarding the use of advanced combination therapy (ACT) in patients with inflammatory bowel disease (IBD). Although the treatment of IBD has come a long way, many patients do not respond or will lose response to currently available treatments over time. ACT has been proposed as a model to create sustained remission in difficult-to-treat IBD patient populations. This review discusses the available literature supporting the use of ACT, followed by practical tips for applying this model of treatment to clinical practice.

RECENT FINDINGS

Both observational and controlled evidence have demonstrated that there may be an increased benefit of ACT in specific IBD patient populations compared to advanced targeted immunomodulator (TIM) monotherapy. Additional data is required to understand how to best use combination TIMs and the long-term risks associated with this strategy.

SUMMARY

While the literature has demonstrated the potential for benefit in both Crohn's disease and ulcerative colitis, the use of ACT is currently off-label and long-term controlled data is needed. The successful application of ACT requires careful consideration of both patient and disease profiles as well as close monitoring of treatment response and adverse events.

Real-world effectiveness of upadacitinib in Crohn's disease: a UK multicentre retrospective cohort study

Background

Upadacitinib is a Janus kinase inhibitor, which has recently been approved for treating Crohn's disease. There are limited real-world studies on the outcomes of upadacitinib in Crohn's disease.

Objective

Our aim was to evaluate the outcomes of upadacitinib in a real-world Crohn's disease cohort.

Methods

We conducted a retrospective, multicentre, cohort study over a 2-year period across National Health Service (NHS) Lothian and Royal Devon University Healthcare NHS Foundation Trust. The primary outcome was treatment persistence at week 24. Secondary endpoints were corticosteroid-free clinical remission (Harvey-Bradshaw Index (HBI)<5) and biomarker remission (C-reactive protein (CRP)≤5 mg/L and faecal calprotectin (FCAL)<250 µg/g) at 12, 24 and 52 weeks. We recorded adverse events.

Results

135 patients commenced upadacitinib as of the 1 January 2024, of which 93 patients with active Crohn's disease were included with a minimum of 12 weeks follow-up. The median follow-up time was 25 weeks (IQR 15-42 weeks). 82% of the cohort had exposure to at least two classes of advanced therapies, and 52% had exposure to at least three classes of advanced therapies. Treatment persistence was 87.1% at week 12, 81.7% at week 24 and 62.8% at week 52. Rates of clinical remission were 64% (42/66), 48% (22/46) and 38% (8/21) at weeks 12, 24 and 52, respectively. Significant reductions in HBI, CRP and FCAL were observed during follow-up. 14% (13/91) had a hospitalisation due to Crohn's disease. Adverse events occurred in 40% (37/93) of the cohort, of which 12% (11/93) were serious.

Conclusion

Upadacitinib was effective in a real-world, highly refractory, Crohn's disease cohort with good persistence.

Real-world evidence of combined treatment of biologics and exclusive enteral nutrition in patients with ileum-dominant Crohn's disease: A multicenter study

BACKGROUND & AIMS

Although biologics were prescribed to achieve and maintain clinical remission of active Crohn's disease (CD), almost half of patients experienced a loss of response or intolerance. Here, we investigated the efficacy of combined treatment of biologics and 16-weeks exclusive enteral nutrition (EEN) in moderate-to-severe CD patients with small intestine lesions.

METHODS

This was a real-world, multicenter retrospective study, from October 2016 to March 2023, medical records of patients registered at three IBD centers were reviewed for patients with ileal or ileocolonic CD in moderate-to-severe activity. All patients received treatment of biologics with concomitant 16-week EEN (BioEEN) or biologics alone (Bio). The clinical outcomes and endoscopic outcomes were assessed at week 16 and 52.

RESULTS

There was no statistically significant difference between Bio (97 patients) and BioEEN group (100 patients) at baseline for demographic and clinical characteristics. Compared to treatment with biologics alone, patients with BioEEN treatment achieved higher rates of clinical response (95.0% vs. 66.0%), clinical remission (87.0% vs. 52.6%), endoscopic response (91.4% vs. 47.4%) including mucosal healing (85.7% vs. 23.7%) at week 16. The superiority of BioEEN sustained in maintenance, with 84.7% (vs. 49.1%) clinical response, 77.8% (vs. 38.6%) clinical remission, 69.2% (vs. 32.6%) endoscopic response and 51.9% (vs. 18.6%) mucosal healing at week 52.

CONCLUSIONS

Combined treatment of biologics and 16-week EEN was an efficient therapeutic strategy with affirmative effectiveness for small intestine diseases of active CD.

Managing Risks with Newer Oral Small Molecules in Patients with Inflammatory Bowel Diseases

PURPOSE OF REVIEW

Treatment of Inflammatory Bowel Diseases (IBD) is challenging; thus, the need for newer therapeutic options with an oral route of administration has led to the development of novel small molecules drugs (SMDs). We aim to highlight the most common Adverse events (AEs) associated with SMDs and recommendations on monitoring for AEs before and during treatment.

RECENT FINDINGS

SMDs, such as Tofacitinib, a JAK inhibitor, have been associated with laboratory abnormalities, infections, and risk of thromboembolic events. Therefore, oral agents with greater selectivity in JAK inhibition, such as tofacitinib and upadacitinib, were later developed. Ozanimod and etrasimod, S1PR agonists, require closer safety profile monitoring by clinicians. Multiple therapies have been recently developed with variable efficacy. However, they have been associated with AEs, and some require close monitoring prior to and during therapy. Clinicians should highlight these adverse events to patients while reassuring the safety profile of these novel SMDs for IBD is favorable.

Optimal Management of Refractory Crohn's Disease: Current Landscape and Future Direction

Refractory Crohn's disease, defined as ongoing inflammation despite the trial of multiple advanced therapies, impacts a number of individuals with Crohn's disease, and leads to significant burden in quality of life and cost. Interventions such as early implementation of advanced therapies, optimization of current therapies prior to switching to an alternative, as well as understanding the overlapping pathophysiology between immune-mediated disorders, however, can help shift the current landscape and reduce the number of patients with refractory disease. As such, in this review we summarize the key takeaways of the latest research in the management of moderate-to-severe Crohn's disease, focusing on maximization of our currently available medications, while also exploring topics such as combination advanced therapies. We also describe evidence for emerging and alternative therapeutic modalities, including fecal microbiota transplant, exclusive enteral feeding, hyperbaric oxygen, stem cell therapy, bone marrow transplant, and posaconazole, with a focus on both the potential impact and specific indications for each.

Novel bispecific nanobody mitigates experimental intestinal inflammation in mice by targeting TNF-α and IL-23p19 bioactivities

BACKGROUND

Inflammatory bowel diseases (IBDs) pose significant challenges in terms of treatment non-response, necessitating the development of novel therapeutic approaches. Although biological medicines that target TNF-α (tumour necrosis factor-α) have shown clinical success in some IBD patients, a substantial proportion still fails to respond.

METHODS

We designed bispecific nanobodies (BsNbs) with the ability to simultaneously target human macrophage-expressed membrane TNF-α (hmTNF-α) and IL-23. Additionally, we fused the constant region of human IgG1 Fc (hIgG1 Fc) to BsNb to create BsNb-Fc.  Our study encompassed in vitro and in vivo characterization of BsNb and BsNb-Fc.

RESULTS

BsNb-Fc exhibited an improved serum half-life, targeting capability and effector function than BsNb. It's demonstrated that BsNb-Fc exhibited superior anti-inflammatory effects compared to the anti-TNF-α mAb (infliximab, IFX) combined with anti-IL-12/IL-23p40 mAb (ustekinumab, UST) by Transwell co-culture assays. Notably, in murine models of acute colitis brought on by 2,4,6-trinitrobenzene sulfonic acid（TNBS) and dextran sulphate sodium (DSS), BsNb-Fc effectively alleviated colitis severity. Additionally, BsNb-Fc outperformed the IFX&UST combination in TNBS-induced colitis, significantly reducing colon inflammation in mice with colitis produced by TNBS and DSS.

CONCLUSION

These findings highlight an enhanced efficacy and improved biostability of BsNb-Fc, suggesting its potential as a promising therapeutic option for IBD patients with insufficient response to TNF-α inhibition.

KEY POINTS

A bispecific nanobody (BsNb) was created to target TNF-α and IL-23p19, exhibiting high affinity and remarkable stability. BsNb-Fc inhibited the release of cytokines in CD4+T cells during co-culture experiments. BsNb-Fc effectively alleviated colitis severity in mouse model with acute colitis induced by DSS or TNBS, outperforming the IFX&UST combination.

Upadacitinib in Crohn's disease

INTRODUCTION

The small molecule and oral selective and reversible Janus kinase (JAK) inhibitor upadacitinib has been approved for the treatment of moderate to severe active Crohn's disease (CD) in adult patients since April 2023 by EMA/FDA.

AREAS COVERED

The approval is based on the two induction studies a maintenance study showing that upadacitinib induction and maintenance therapy was superior to placebo. The approval of upadacitinib in CD expands the therapeutic armamentarium for the management of inflammatory bowel diseases (IBD). Upadacitinib is the first and only JAK inhibitor approved in patients with CD and provides a novel mechanism of action and the first advanced oral treatment option for patients with CD. Upadacitinib is approved for the treatment of other immunologically mediated disorders, including ulcerative colitis, rheumatoid arthritis, psoriasis arthritis, axial spondylarthritis, ankylosing spondylitis, and atopic dermatitis. Treatment of atopic dermatitis has been approved from the age of 12 years.

EXPERT OPINION

Upadacitinib may cause relevant changes of our current treatment algorithms for Crohn's disease. Further real-world studies and head-to-head comparisons are needed to position upadacitinib in our current treatment algorithms for CD.

Attitudes, perceptions and barriers in implementing therapeutic drug monitoring for anti-TNFs in inflammatory bowel disease: a survey from the Middle East

Background

A growing body of evidence underscores the beneficial impact of therapeutic drug monitoring (TDM) on the efficacy and cost-effectiveness of anti-tumour necrosis factor (TNF) therapy in patients with inflammatory bowel disease (IBD).

Objectives

We surveyed clinician attitudes, perceptions and barriers related to TDM in IBD in the Middle East.

Design

A 15-question survey was distributed through national gastroenterological societies in five Middle Eastern countries (UAE, Saudi Arabia, Kuwait, Lebanon and Egypt).

Methods

Data on clinician characteristics, demographics, utilization patterns and obstacles related to the adoption of TDM with anti-TNFs were gathered. Logistic regression analysis was used to predict factors influencing the utilization of TDM.

Results

Among 211 respondents (82% male), 82% were consultants, 8% were physicians with an interest in gastroenterology (GI), and 6% were GI trainees. Of these, 152 met inclusion criteria, treating >5 IBD patients per month and ⩾1 with an anti-TNF per month. TDM was used in clinical practice by 78% (95% CI: 71-85) of respondents. TDM was utilized following the loss of response (LOR) in 93%, for primary non-response (PNR) in 40% and before restarting anti-TNF therapy after a drug holiday in 33% of respondents, while 34% used TDM proactively. No specific factors were associated with the use of TDM. Barriers to TDM use included cost (85%), time lag to results (71%) and lack of insurance reimbursement (65%). Overall knowledge of TDM (70%), interpretation and actioning of results (76%) or awareness of clinical guidelines (57%) were not perceived as barriers. If barriers were removed, 95% would use TDM more frequently; 93% for LOR, 60% for PNR, 50% when restarting after a drug holiday, and 54% would use TDM proactively.

Conclusion

Most gastroenterologists use TDM for LOR, with cost, time lag and insurance reimbursement being significant barriers. Addressing these barriers would increase the judicious use of reactive and proactive TDM to optimize anti-TNF therapy in IBD.

Efficacy and safety of 48 weeks of guselkumab for patients with Crohn's disease: maintenance results from the phase 2, randomised, double-blind GALAXI-1 trial

BACKGROUND

Many patients with moderately to severely active Crohn's disease do not respond to available therapies or lose response over time. The GALAXI-1 study previously found that three intravenous guselkumab dosages showed superior clinical and endoscopic outcomes over placebo at week 12 in patients with moderately to severely active Crohn's disease. We report the safety and efficacy of subcutaneous guselkumab maintenance regimens to week 48 in the GALAXI-1 study.

METHODS

We did a phase 2, randomised, multicentre, double-blind trial. Adult patients with moderately to severely active Crohn's disease were randomly allocated with a computer-generated randomisation schedule to receive one of five treatment groups, with regimens consisting of an intravenous induction phase transitioning to a subcutaneous maintenance phase starting at week 12 in a treat-through design: (1) guselkumab 200→100 mg group (200 mg intravenous at weeks 0, 4, and 8, then 100 mg subcutaneous every 8 weeks; (2) guselkumab 600→200 mg group (600 mg intravenous at weeks 0, 4, and 8, then 200 mg subcutaneous every 4 weeks); (3) guselkumab 1200→200 mg group (1200 mg intravenous at weeks 0, 4, and 8, then 200 mg subcutaneous every 4 weeks); (4) ustekinumab group (approximately 6 mg/kg intravenous at week 0, then 90 mg subcutaneous every 8 weeks); or (5) placebo group (placebo induction followed by either placebo maintenance [for those with CDAI clinical response at week 12] or crossover to ustekinumab [for those without CDAI clinical response at week 12]). Endpoints assessed at week 48 included CDAI remission (CDAI score <150), endoscopic response (≥50% improvement from baseline in SES-CD or SES-CD score ≤2), and endoscopic remission (SES-CD score ≤2) in the primary efficacy analysis population of all randomised patients who received at least one dose of study drug, excluding those discontinued during a temporary study pause. Safety analyses included all randomised patients who received at least one study drug dose. This trial is registered at Clinical Trials.gov (NCT03466411) and is active but not recruiting.

FINDINGS

Among 700 patients screened, 309 (112 biologic-naive; 197 biologic-experienced) were included in the primary efficacy analysis population: 61 in the guselkumab 200→100 mg group, 63 in the guselkumab 600→200 mg group, 61 in the guselkumab 1200→200 mg group, 63 in the ustekinumab group, and 61 in the placebo group. 126 (41%) women and 183 (59%) men were included, with median age 36·0 years (IQR 28·0-49·0). At week 48, the numbers of patients with CDAI clinical remission were 39 (64%) in the guselkumab 200→100 mg group, 46 (73%) in the guselkumab 600→200 mg group, 35 (57%) in the guselkumab 1200→200 mg group, and 37 (59%) in the ustekinumab group. The corresponding numbers of patients with endoscopic response were 27 (44%), 29 (46%), 27 (44%), and 19 (30%), respectively, and endoscopic remission was seen in 11 (18%), 11 (17%), 20 (33%), and four (6%) patients, respectively. In the placebo group, 15 patients were in CDAI clinical response at week 12 and continued placebo; of these, nine (60%) were in clinical remission at week 48. 44 patients in the placebo group were not in CDAI clinical response at week 12 and crossed over to ustekinumab; of these, 26 (59%) were in clinical remission at week 48. Up to week 48, adverse events frequencies in the safety population (n=360) were 46 (66%) of 70 patients (464·9 events per 100 patient-years of follow-up) in the placebo group, 163 (74%) of 220 patients (353·1 per 100 patient-years) in the three guselkumab groups combined, and 60 (85%) of 71 patients (350·7 per 100 patient-years) in the ustekinumab group. Among patients treated with guselkumab or ustekinumab, the most frequently reported infections up to week 48 were nasopharyngitis (25 [11%] of 220 guselkumab recipients, 12 [11%] of 114 ustekinumab recipients) and upper respiratory infections (13 [6%] guselkumab recipients, eight [7%] ustekinumab recipients). After week 12, one patient who responded to placebo induction and two guselkumab-treated patients had serious infections. No active tuberculosis, opportunistic infections, or deaths occurred.

INTERPRETATION

Patients receiving guselkumab intravenous induction and subcutaneous maintenance treatment achieved high rates of clinical and endoscopic efficacy up to week 48. No new safety concerns were identified.

FUNDING

Janssen Research & Development.

Effectiveness of Partial Enteral Nutrition as Add-On to Biologics in Patients With Refractory and Difficult-to-Treat Crohn's Disease: A Pilot Study

Background

Partial enteral nutrition (PEN) is a well-established treatment for children with Crohn's disease (CD). However, its efficacy in adults with CD remains uncertain. We aimed to assess the effectiveness of PEN as an add-on to escalated biological therapy in adults with CD who have lost response to biologics.

Methods

We conducted a retrospective observational study including patients who had lost response to biologics and received PEN in combination with escalated treatment, compared to those treated only with escalated therapy. The primary endpoint was steroid-free clinical remission (CR) at 24 weeks. Secondary endpoints included transmural healing (TH) and response (TR) rates along with selected clinical outcomes.

Results

Forty-two patients were screened; 12 (28.6%) were excluded for complicated disease and 30 (71.4%) were included in the final analysis. Fourteen (46.7%) patients completed PEN treatment at 8 weeks, while 16 patients (53.3%) discontinued treatment due to intolerance and continued with escalation of biologic (BT group). At 24 weeks, 9 patients (64.3%) in the PEN group achieved CR, compared to 4 patients (25%) in the BT group (P = .03). The TR rate was 64.9% in the PEN group and 25% in the BT group (P = .03). Patients receiving PEN exhibited an increase in albumin levels compared to those in the BT group (Δ = 0.5; P = .02). A higher rate of therapy changes (68.7%) was observed in the BT group compared to 14.2% in the PEN group (P = .004). Prior failure to 2 lines of biological therapy was associated with adherence to PEN (OR = 1.583; CI = 1.06-2.36; P = .01).

Conclusions

In patients who had lost response to biologics, PEN in combination with escalated biologics was associated with CR and TR and improved nutritional status. Hence, the addition of PEN should be considered for patients with difficult-to-treat CD.

Guselkumab in Patients With Moderately to Severely Active Ulcerative Colitis: QUASAR Phase 2b Induction Study

BACKGROUND & AIMS

The QUASAR Phase 2b Induction Study evaluated the efficacy and safety of guselkumab, an interleukin-23p19 subunit antagonist, in patients with moderately to severely active ulcerative colitis (UC) with prior inadequate response and/or intolerance to corticosteroids, immunosuppressants, and/or advanced therapy.

METHODS

In this double-blind, placebo-controlled, dose-ranging, induction study, patients were randomized (1:1:1) to receive intravenous guselkumab 200 or 400 mg or placebo at weeks 0/4/8. The primary endpoint was clinical response (compared with baseline, modified Mayo score decrease ≥30% and ≥2 points, rectal bleeding subscore ≥1-point decrease or subscore of 0/1) at week 12. Guselkumab and placebo week-12 clinical nonresponders received subcutaneous or intravenous guselkumab 200 mg, respectively, at weeks 12/16/20 (uncontrolled study period).

RESULTS

The primary analysis population included patients with baseline modified Mayo scores ≥5 and ≤9 (intravenous guselkumab 200 mg, n = 101; 400 mg, n = 107; placebo, n = 105). Week-12 clinical response percentage was greater with guselkumab 200 mg (61.4%) and 400 mg (60.7%) vs placebo (27.6%; both P < .001). Greater proportions of guselkumab-treated vs placebo-treated patients achieved all major secondary endpoints (clinical remission, symptomatic remission, endoscopic improvement, histo-endoscopic mucosal improvement, and endoscopic normalization) at week 12. Among guselkumab week-12 clinical nonresponders, 54.3% and 50.0% of patients in the 200- and 400-mg groups, respectively, achieved clinical response at week 24. Safety was similar among guselkumab and placebo groups.

CONCLUSIONS

Guselkumab intravenous induction was effective vs placebo in patients with moderately to severely active UC. Guselkumab was safe, and efficacy and safety were similar between guselkumab dose groups.

CLINICALTRIALS

gov number: NCT04033445.

Mirikizumab for the treatment of moderate to severe ulcerative colitis

Despite a growing number of available therapeutic options for ulcerative colitis (UC), up to 50% of patients do not respond to initial treatment or lose response over time, highlighting the need for novel therapies. The IL-23 pathway has emerged as an important therapeutic target for UC. Mirikizumab is a humanized IgG4 monoclonal antibody against the p19 subunit of IL-23, dosed intravenously during induction and subcutaneously during maintenance. It is effective for the induction and maintenance of remission in moderately to severely active UC, including patients with prior failure of biological or tofacitinib therapy. Like other IL-23 antagonists, mirikizumab has a favorable safety profile. It is the first agent of its class to receive regulatory approval for moderately to severely active UC in Europe.

Ulcerative Colitis in Adults: A Review

Importance

Ulcerative colitis (UC) is a chronic inflammatory condition of the colon, with a prevalence exceeding 400 per 100 000 in North America. Individuals with UC have a lower life expectancy and are at increased risk for colectomy and colorectal cancer.

Observations

UC impairs quality of life secondary to inflammation of the colon causing chronic diarrhea and rectal bleeding. Extraintestinal manifestations, such as primary sclerosing cholangitis, occur in approximately 27% of patients with UC. People with UC require monitoring of symptoms and biomarkers of inflammation (eg, fecal calprotectin), and require colonoscopy at 8 years from diagnosis for surveillance of dysplasia. Risk stratification by disease location (eg, Montreal Classification) and disease activity (eg, Mayo Score) can guide management of UC. First-line therapy for induction and maintenance of remission of mild to moderate UC is 5-aminosalicylic acid. Moderate to severe UC may require oral corticosteroids for induction of remission as a bridge to medications that sustain remission (biologic monoclonal antibodies against tumor necrosis factor [eg, infliximab], α4β7 integrins [vedolizumab], and interleukin [IL] 12 and IL-23 [ustekinumab]) and oral small molecules that inhibit janus kinase (eg, tofacitinib) or modulate sphingosine-1-phosphate (ozanimod). Despite advances in medical therapies, the highest response to these treatments ranges from 30% to 60% in clinical trials. Within 5 years of diagnosis, approximately 20% of patients with UC are hospitalized and approximately 7% undergo colectomy. The risk of colorectal cancer after 20 years of disease duration is 4.5%, and people with UC have a 1.7-fold higher risk for colorectal cancer compared with the general population. Life expectancy in people with UC is approximately 80.5 years for females and 76.7 years for males, which is approximately 5 years shorter than people without UC.

Conclusions and Relevance

UC affects approximately 400 of every 100 000 people in North America. An effective treatment for mild to moderate UC is 5-aminosalicylic acid, whereas moderate to severe UC can be treated with advanced therapies that target specific inflammation pathways, including monoclonal antibodies to tumor necrosis factor, α4β7 integrins, and IL-12 and IL-23 cytokines, as well as oral small molecule therapies targeting janus kinase or sphingosine-1-phosphate.

Pharmacological Therapy in Inflammatory Bowel Diseases: A Narrative Review of the Past 90 Years

Inflammatory Bowel Diseases had their first peak in incidence in countries in North America, Europe, and Oceania and are currently experiencing a new acceleration in incidence, especially in Latin America and Asia. Despite technological advances, 90 years after the development of the first molecule for the treatment of IBD, we still do not have drugs that promote disease remission in a generalized way. We carried out a narrative review on therapeutic advances in the treatment of IBD, the mechanisms of action, and the challenges facing the therapeutic goals in the treatment of IBD. Salicylates are still used in the treatment of Ulcerative Colitis. Corticosteroids have an indication restricted to the period of therapeutic induction due to frequent adverse events, while technologies with less systemic action have been developed. Most immunomodulators showed a late onset of action, requiring a differentiated initial strategy to control the disease. New therapeutic perspectives emerged with biological therapy, initially with anti-TNF, followed by anti-integrins and anti-interleukins. Despite the different mechanisms of action, there are similarities between the general rates of effectiveness. These similar results were also evidenced in JAK inhibitors and S1p modulators, the last therapeutic classes approved for the treatment of IBD.

Editorial: If STRIDE-II is the hammer, then Crohn's disease and ulcerative colitis are not the same nails-Authors' reply

This article is linked to Dignass et al papers. To view these articles, visit https://doi.org/10.1111/apt.17622 and https://doi.org/10.1111/apt.17640

Ulcerative colitis

Ulcerative colitis is a lifelong inflammatory disease affecting the rectum and colon to a variable extent. In 2023, the prevalence of ulcerative colitis was estimated to be 5 million cases around the world, and the incidence is increasing worldwide. Ulcerative colitis is thought to occur in people with a genetic predisposition following environmental exposures; gut epithelial barrier defects, the microbiota, and a dysregulated immune response are strongly implicated. Patients usually present with bloody diarrhoea, and the diagnosis is based on a combination of clinical, biological, endoscopic, and histological findings. The aim of medical management is, first, to induce a rapid clinical response and normalise biomarkers and, second, to maintain clinical remission and reach endoscopic normalisation to prevent long-term disability. Treatments for inducing remission include 5-aminosalicylic acid drugs and corticosteroids. Maintenance treatments include 5-aminosalicylic acid drugs, thiopurines, biologics (eg, anti-cytokines and anti-integrins), and small molecules (Janus kinase inhibitors and sphingosine-1-phosphate receptor modulators). Although the therapeutic options are expanding, 10-20% of patients still require proctocolectomy for medically refractory disease. The keys to breaking through this therapeutic ceiling might be the combination of therapeutics with precision and personalised medicine.

Fecal Fungal Microbiota (Mycobiome) Study as a Potential Tool for Precision Medicine in Inflammatory Bowel Disease

There is growing evidence of the role of fungal microbiota in the pathogenesis of inflammatory bowel disease (IBD). Fungi can exert direct pro-inflammatory effects or modify the bacterial composition via interkingdom interactions. Although several studies have demonstrated alterations in the fecal fungal microbiota composition in IBD, there is a wide variation in the mycobiome in different populations, with no definite pattern that can define the mycobiome in IBD having yet been identified. Recent work has suggested that characterizing the fecal fungal composition may influence therapeutic decisions and help to predict outcomes in a subset of IBD patients. In this study, we review the current literature on the emerging role of the fecal mycobiome as a potential tool for precision medicine in IBD.

An update on the safety of long-term vedolizumab use in inflammatory bowel disease

INTRODUCTION

Vedolizumab (Entyvio) is a humanized monoclonal antibody that disrupts the interaction between α4β7 integrin on circulating T-lymphocytes and MAdCAM-1 on the vascular endothelium to prevent their egress to sites of gut inflammation. It has proven therapeutic efficacy for the treatment of moderate-to-severe Crohn's disease, ulcerative colitis, and pouchitis.

AREAS COVERED

This narrative review assesses the safety profile of vedolizumab from the registration trial programs, open-label extension studies, observational real-world data, and pooled safety analyses. This includes an evaluation of the long-term overall safety in special populations typically underrepresented in clinical trials.

EXPERT OPINION

Vedolizumab is an effective therapy for inflammatory bowel disease with a well-established safety profile. No unexpected long-term safety signals have been identified. Safety data in pregnancy, in pediatric and elderly populations, in patients undergoing surgery, and in patients with a prior history of cancer are reassuring. Due to its safety merits, we propose that vedolizumab is an excellent candidate for advanced combination treatment with an anti-cytokine approach using another biologic or novel small molecule inhibitor. This is important in patients with medically refractory IBD, in patients at high risk of developing disease-related complications, or in patients with concomitant uncontrolled immune-mediated inflammatory diseases.

In-hospital management of inflammatory bowel disease

PURPOSE OF REVIEW

The management of hospitalized patients with inflammatory bowel disease (IBD) is complex. Despite considerable therapeutic advancements in outpatient ulcerative colitis and Crohn's disease management, the in-hospital management continues to lag with suboptimal outcomes. The purpose of this review is to provide a brief overview of our approach to managing patients hospitalized with acute severe ulcerative colitis (ASUC) and Crohn's disease-related complications, followed by a summary of emerging evidence for new management approaches.

RECENT FINDINGS

ASUC has seen the emergence of well validated prognostic models for colectomy as well as the development of novel treatment strategies such as accelerated infliximab dosing, Janus kinase inhibitor therapy, and sequential therapy, yet the rate of colectomy for steroid-refractory ASUC has not meaningfully improved. Crohn's disease has seen the development of better diagnostic tools, early Crohn's disease-related complication stratification and identification, as well as better surgical techniques, yet the rates of hospitalization and development of Crohn's disease-related complications remain high.

SUMMARY

Significant progress has been made in the in-hospital IBD management; however, both the management of ASUC and hospitalized Crohn's disease remain a challenge with suboptimal outcomes. Critical knowledge gaps still exist, and dedicated studies in hospitalized patients with IBD are needed to address them.

Risk-Benefit of IBD Drugs: A Physicians and Patients Survey

BACKGROUND

Treatment choices for patients with inflammatory bowel disease (IBD) are based on the balance between risks and benefits. Our AI was to compare the perspectives of patients and physicians in evaluating the risks and benefits before initiating therapy for IBD.

METHODS

An anonymous survey was conducted between March and August 2022. All patients with confirmed IBD and all physicians who attended an IBDscope webinar were invited to participate.

RESULTS

In total, 367 patients and 146 physicians participated. For most patients (71.4%) and physicians (89.0%), efficacy and safety were equally important. Clinical improvement and clinical remission were the most relevant outcomes for patients (90.9 and 88.4), while clinical remission and endoscopic remission were for physicians (90.0 and 87.6). The main factors in the benefit-risk assessment were quality of life (95.1%), disease activity (87.5%), and presence of comorbidities (84.5%) for patients, and presence of comorbidities (99.3%), disease activity (97.9%), and prior failure to biologics/small molecules (96.6%) for physicians. Based on patients' and physicians' opinions, the risk of serious infections, malignancies, cardiovascular events, death, relapse, all infections, surgery, and hospitalization should be included in the benefit-risk assessment.

CONCLUSION

Physicians and patients have different priorities in evaluating the benefit-risk balance of a new therapy.

Personalize, participate, predict, and prevent: 4Ps in inflammatory bowel disease

Inflammatory bowel disease (IBD), which includes Crohn's disease (CD) and ulcerative colitis (UC), is a complex, immune-mediated, disorder which leads to several gastrointestinal and systemic manifestations determining a poor quality of life, disability, and other negative health outcomes. Our knowledge of this condition has greatly improved over the last few decades, and a comprehensive management should take into account both biological (i.e., disease-related, patient-related) and non-biological (i.e., socioeconomic, cultural, environmental, behavioral) factors which contribute to the disease phenotype. From this point of view, the so called 4P medicine framework, including personalization, prediction, prevention, and participation could be useful for tailoring ad hoc interventions in IBD patients. In this review, we discuss the cutting-edge issues regarding personalization in special settings (i.e., pregnancy, oncology, infectious diseases), patient participation (i.e., how to communicate, disability, tackling stigma and resilience, quality of care), disease prediction (i.e., faecal markers, response to treatments), and prevention (i.e., dysplasia through endoscopy, infections through vaccinations, and post-surgical recurrence). Finally, we provide an outlook discussing the unmet needs for implementing this conceptual framework in clinical practice.

Insights into Mesalazine Use in Clinical Practice of Young Gastroenterologists

BACKGROUND

Mesalazine is among the medications most prescribed by gastroenterologists, with variable and controversial use in different settings. We aimed to explore the use of mesalazine in the clinical practice of young gastroenterologists.

METHODS

A web-based electronic survey was distributed to all participants of the National Meeting of the Italian Young Gastroenterologist and Endoscopist Association.

RESULTS

A total of 101 participants took part in the survey, with a majority (54.4%) being aged >30 years, 63.4% of whom were trainees in academic hospitals, and 69.3% of whom were involved in the clinical management of inflammatory bowel disease (IBD). While both non-dedicated and IBD physicians generally agreed on the appropriate dose of mesalazine for mild ulcerative colitis (UC), significant differences were observed between the two groups for moderate-severe ulcerative colitis (UC). Additionally, in IBD patients who were starting immuno-modulators and/or biologics, 80% of IBD-dedicated physicians continued to prescribe mesalazine, compared to 45.2% of non-dedicated physicians (p = 0.002). Indeed, 48.4% of non-dedicated IBD physicians did not acknowledge mesalazine for colorectal cancer chemoprevention. With regards to Crohn's disease, it is mainly used by 30.1% of IBD physicians for preventing postoperative recurrence of Crohn's disease. Finally, 57.4% used mesalazine for symptomatic uncomplicated diverticular disease, and 84.2% did not recommend its use for irritable bowel syndrome.

CONCLUSIONS

This survey showed heterogeneous behaviors in the daily use of mesalazine, mainly in the management of IBD. Educational programs and novel studies are needed to clarify its use.

Therapeutic targets for inflammatory bowel disease: proteome-wide Mendelian randomization and colocalization analyses

BACKGROUND

Identifying new drug targets for inflammatory bowel disease (IBD) is urgently needed. The proteome is a major source of therapeutic targets. We conducted a proteome-wide Mendelian randomization (MR) and colocalization analyses to identify possible targets for IBD.

METHODS

Summary-level data of 4907 circulating protein levels were extracted from a large-scale protein quantitative trait loci study including 35,559 individuals. Genetic associations with IBD and its subtypes were obtained from the Inflammatory Bowel Disease Genetics Consortium (25,024 cases and 34,915 controls), the FinnGen study (7206 cases and 253,199 controls), and the UK Biobank study (7045 cases and 449,282 controls). MR analysis was conducted to estimate the associations between protein and IBD risk. The colocalization analysis was used to examine whether the identified proteins and IBD shared casual variants.

FINDINGS

Genetically predicted levels of 3, and 5 circulating proteins were associated with IBD and ulcerative colitis (UC), respectively. With high supporting evidence of colocalization, genetically predicted MST1 (macrophage stimulating 1) and HGFAC (hepatocyte growth factor activator) levels were inversely associated with IBD risks. The associations of STAT3 (signal transducer and activator of transcription 3), MST1, CXCL5 (C-X-C motif chemokine ligand 5), and ITPKA (inositol-trisphosphate 3-kinase A) with the risk of UC were supported by colocalization analysis.

INTERPRETATION

The proteome-wide MR investigation identified many proteins associated with the risk of IBD. MST1, HGFAC, STAT3, ITPKA, and CXCL5 deserve further investigation as potential therapeutic targets for IBD.

FUNDING

SCL is supported by research grants from the Swedish Research Council for Health, Working Life and Welfare (Forte; grant no. 2018-00123) and the Swedish Research Council (Vetenskapsrådet; grant no. 2019-00977). XYW is supported by research grants from the National Natural Science Foundation of China (81970494) and Key Project of Research and Development Plan of Hunan Province (2019SK2041). XL is supported by research grants from the Natural Science Fund for Distinguished Young Scholars of Zhejiang Province (LR22H260001).

Breaking through the therapeutic ceiling of inflammatory bowel disease: Dual-targeted therapies

Emerging biologics and small-molecule drugs have changed the clinical status quo of inflammatory bowel disease (IBD). However, current treatments remain at a standstill in terms of response and remission in many cases. Accumulating evidence indicates that dual-targeted therapy (DTT) could be promising in overcoming the existing ceiling of IBD treatment. However, data on the efficacy and safety of DTT on Crohn's disease and ulcerative colitis are still limited or insufficient. Moreover, there is a lack of studies delineating the mechanisms of DTT. Given that various targeted drugs have different targets among the extensive redundant inflammatory networks, DTT could result in various outcomes. In this review, we have summarized the current data on the safety, effectiveness, and clinical development status of novel targeted drugs related to refractory IBD, and have explored the mechanism of action of therapy. We have categorized therapeutic agents into "Therapeutic Agents Targeting Cellular Signaling Pathways" and "Therapeutic Agents Targeting Leukocyte Trafficking" based on the different therapeutic targets, and also by classifying therapeutic agents targeting the cellular signaling pathways into "JAK-dependent" and "JAK-independent," and placed the existing drug combinations into 3 categories based on their mechanisms, namely, overlapping, synergistic, and complementary effects. Lastly, we have proposed the possible mechanisms of DTT to conceive a theoretical framework for clinical decision-making and further drug development and research from an IBD standpoint.

Single-cell RNA-sequencing combined with bulk RNA-sequencing analysis of peripheral blood reveals the characteristics and key immune cell genes of ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is a complicated disease caused by the interaction between genetic and environmental factors that affects mucosal homeostasis and triggers an inappropriate immune response. Single-cell RNA sequencing (scRNA-seq) can be used to rapidly obtain the precise gene expression patterns of thousands of cells in the intestine, analyze the characteristics of cells with the same phenotype, and provide new insights into the growth and development of intestinal organs, the clonal evolution of cells, and immune cell changes. These findings can provide new ideas for the diagnosis and treatment of intestinal diseases.

AIM

To identify clinical phenotypes and biomarkers that can predict the response of UC patients to specific therapeutic drugs and thus aid the diagnosis and treatment of UC.

METHODS

Using the Gene Expression Omnibus (GEO) database, we analyzed peripheral blood cell subtypes of patients with UC by scRNA-seq combined with bulk RNA sequencing (RNA-seq) to reveal the core genes of UC. We then combined weighted gene correlation network analysis (WGCNA) and least absolute shrinkage and selection operator (LASSO) analysis to reveal diagnostic markers of UC.

RESULTS

After processing the scRNA-seq data, we obtained data from approximately 24340 cells and identified 17 cell types. Through intercellular communication analysis, we selected monocyte marker genes as the candidate gene set for the prediction model. Construction of a WGCNA coexpression network identified RhoB, cathepsin D (CTSD) and zyxin (ZYX) as core genes. Immune infiltration analysis showed that these three core genes were strongly correlated with immune cells. Functional enrichment analysis showed that the differentially expressed genes were closely related to immune and inflammatory responses, which are associated with many challenges in the diagnosis and treatment of UC.

CONCLUSION

Through scRNA-seq analysis, LASSO diagnostic model building and WGCNA, we identified RhoB, CTSD and ZYX as core genes of UC that are closely related to monocyte infiltration that may serve as diagnostic markers and molecular targets for UC therapeutic intervention.

Integrated systematic pharmacology analysis and experimental validation to reveal the mechanism of action of Semen aesculi on inflammatory bowel diseases

BACKGROUND AND ETHNOPHARMACOLOGICAL RELEVANCE

Semen aesculi (SA), a traditional Chinese herb, has been used in the treatment of gastrointestinal disease for thousands of years. The escin was the main components of SA. A growing number of research showed that escin has a wide range of pharmacological activities in intestinal barrier dysfunction.

AIM OF THE STUDY

Inflammatory bowel diseases (IBD) are an idiopathic disease of the intestinal tract with the hallmark features of mucosal inflammation and loss of barrier function. The theory of traditional Chinese medicine (TCM) suggests that SA plays a potential role in protecting the gastrointestinal diseases. The present study aimed to explore the effects of SA on the intestinal barrier under existing inflammatory conditions and elucidate underlying mechanisms.

MATERIALS AND METHODS

The bioactive components of SA and their predicted biological targets were combined to develop a compound target pathway network. It is used to predict the bioactive components, molecular targets, and molecular pathways of SA in improving IBD. The ingredients of SA were extracted by decoction either in water and ethanol and separated into four fractions (AE, EE, PEE and PCE). The effects of extractions were evaluated in the lipopolysaccharide (LPS)-induced RAW264.7 macrophages cell model, LPS-induced intestinal barrier injury model and imodium-induced constipation model. The high-performance liquid chromatography (HPLC) analysis was performed to identify the bioactive components.

RESULTS

The compound-target pathway network was identified with 10 bioactive compounds, 166 IBD-related targets, and 52 IBD-related pathways. In LPS-induced RAW264.7 cells, PEE and PCE significantly decreased nitric oxide (NO) production and TNF-α level. In mice, PEE and PCE administration improved intestinal barrier damage, increased intestinal motility, reduced levels of TNF-α and diamine oxidase (DAO). Furthermore, PEE and PCE administration not only decreased expression of p-Akt, p-IκBα, nuclear p-p65, and TNF-α level, but also increased expression of the zonula occludin-1 (ZO-1) in LPS-induced intestinal barrier injury model. The escin content of AE, EE, PEE and PCE gradually increased with an increase of the bioactivity.

CONCLUSIONS

Escin was the main bioactive components of SA. The effects of SA on IBD were mediated by repairing the intestinal barrier and promoting intestinal motility. The mechanism of action of SA is related to inhibiting the Akt/NF-κB signaling pathway in intestinal tissue, at least, in part. Our results provide a scientific basis for further exploring the mechanisms involved in the beneficial effects of SA in IBD.

The Lactobacillus gasseri G098 Strain Mitigates Symptoms of DSS-Induced Inflammatory Bowel Disease in Mice

Inflammatory bowel disease (IBD) is a recurring inflammatory disease of the gastrointestinal tract with unclear etiology, but it is thought to be related to factors like immune abnormalities and gut microbial dysbiosis. Probiotics can regulate host immunity and gut microbiota; thus, we investigated the alleviation effect and mechanism of the strain Lactobacillus gasseri G098 (G098) on dextran sodium sulfate (DSS)-induced colitis in mice. Three groups of mice (n = 8 per group) were included: normal control (NC), DSS-induced colitis mice (DSS), and colitis mice given strain (G098). Our results showed that administering G098 effectively reversed DSS-induced colitis-associated symptoms (mitigating weight loss, reducing disease activity index and pathology scores; p < 0.05 in all cases) and prevented DSS-induced mortality (62.5% in DSS group; 100% in G098 group). The mortality rate and symptom improvement by G098 administration was accompanied by a healthier serum cytokine balance (significant decreases in serum pro-inflammatory factors, interleukin (IL)-6 [p < 0.05], IL-1β [p < 0.01], and tumor necrosis factor (TNF)-α [p < 0.001], and significant increase in the serum anti-inflammatory factor IL-13 [p < 0.01], compared with DSS group) and gut microbiome modulation (characterized by a higher gut microbiota diversity [p < 0.05], significantly more Firmicutes and Lachnoclostridium [p < 0.05], significantly fewer Bacteroidetes [p < 0.05], and significant higher gene abundances of sugar degradation-related pathways [p < 0.05], compared with DSS-treated group). Taken altogether, our results suggested that G098 intake could mitigate DSS-induced colitis through modulating host immunity and gut microbiome, and strain treatment is a promising strategy for managing IBD.