[Old and New Biologics and Small Molecules in Inflammatory Bowel Disease: Anti Integrins].

Recently, novel biologics or small molecular drugs have been introduced for overcoming the unmet needs associated with anti-tumor necrosis factor α agents for inflammtory bowel disease (IBD) treatment. Among these novel drugs, anti integrin agents block leukocyte trafficking to the intestine by blocking the interaction between integrin and cell adhesion molecules. Vedolizumab (anti-α4ß7) is most widely used anti-integrin approved in both ulcerative colitis and Crohn's disease .It has been shown to be effective in both induction and maintenance therapy with a favorable safety profile due to gut selectivity. Several models incorporating clinical, genetic, immune and gut microbial markers to predict response to vedolizumab in IBD have been developed. Etrolizumab (anti-ß7) blocks leukocyte trafficking via α4ß7 and cell adhesion via αEß7 integrins. In addition, the introduction of subcutaneous vedolizumab showed similar efficacy and safety with improved patients' convenience. Other investigational anti-integrin therapies include abrilumab (anti-α4ß7 IgG2), PN-943 (orally administered and gut-restricted α4ß7 antagonist peptide), AJM300 (orally active small molecule inhibitor of α4), and ontamalimab (anti-MAdCAM-1 IgG).

Immunity in digestive diseases: new drugs for inflammatory bowel disease treatment-insights from Phase II and III trials.

BACKGROUND: Inflammatory bowel disease (IBD), encompassing Crohn's disease (CD) and ulcerative colitis (UC), continues to challenge treatment paradigms. Advancements in therapeutic options have been have been driven by Phase 2 and 3 clinical trials of new drug classes, particularly sphingosine-1-phosphate (S1P) modulators and interleukin-23 (IL-23) inhibitors. METHODS: This review synthesizes findings from Phase 2 and 3 clinical trials conducted up to early 2024, focusing on the impact of S1P modulators and IL-23 inhibitors on IBD management. Drugs such as ozanimod, etrasimod, risankizumab, mirikizumab, guselkumab, and brasikumab were evaluated for their efficacy and safety profiles. RESULTS: S1P modulators, such as ozanimod and etrasimod, effectively regulate immune cell trafficking to reduce inflammation and several trials highlight their clinical effectiveness in both inducing and maintaining remission in IBD, highlighting its long-term safety and sustained therapeutic effects. Additionally, IL-23 inhibitors including risankizumab, mirikizumab, and guselkumab, which disrupt key inflammatory cytokine pathways, have already shown significant effectiveness in inducing and maintaining remission in both CD and UC, with favorable safety profiles across multiple studies, suggesting their potential as critical components in managing IBD. CONCLUSIONS: The clinical trials indicate that both S1P modulators and IL-23 inhibitors offer promising therapeutic benefits and maintain strong safety profiles, positioning them as potential cornerstone treatments for IBD. Despite these advancements, further exploration into long-term safety and the development of personalized treatment strategies is essential for maximizing clinical outcomes.

Examining linaclotide for the treatment of chronic idiopathic constipation.

INTRODUCTION: Chronic idiopathic constipation (CIC) is characterized by infrequent bowel movements and hard stools lasting for at least three months or longer. This disease affects 8-12% of the US population and 10-17% of the world population. Treatment and management involve identifying the primary cause, changing dietary habits, and adequate physical activity. Linaclotide is a guanylate cyclase-agonist acting locally in the luminal surface of the intestinal enterocyte leading to a signal transduction cascade, activation of the cystic fibrosis transmembrane conductance regulator (CFTR), thus increasing secretion of chloride and bicarbonate into the intestinal lumen with eventual increased intestinal fluid and faster transit time. AREAS COVERED: We reviewed multiple studies and did a thorough literature review on CIC including its pathophysiology. Through this literature review, we were able to discuss and give the context and rationale for drug regimens indicated for CIC. EXPERT OPINION: The era we live in right now is akin to nutrient-rich and fertilized soil as knowledge and resources are abundant. The opportunities and potential are endless. Constipation being more extensively studied, our understanding of medications and diseases broadens, leading to novel medications being discovered. Linaclotide is a pioneer in this aspect and can pave the way for future generations.

The effect of rifaximin and lactulose treatments to chronic hepatic encephalopathy rats: An [18F]PBR146 in-vivo neuroinflammation imaging study.

INTRODUCTION: Hepatic encephalopathy (HE) is a severe neuropsychiatric complication of liver diseases characterized by neuroinflammation. The efficacies of nonabsorbable rifaximin (RIF) and lactulose (LAC) have been well documented in the treatment of HE. [18F]PBR146 is a translocator protein (TSPO) radiotracer used for in vivo neuroinflammation imaging. This study investigated anti-neuroinflammation effect of RIF or/and LAC in chronic HE rats by [18F]PBR146 micro-PET/CT. METHODS: Bile duct ligation (BDL) operation induced chronic HE models, and this study included Sham+normal saline (NS), BDL+NS, BDL+RIF, BDL+LAC, and BDL+RIF+LAC groups. Behavioral assessment was performed to analyze the motor function, and fecal samples were collected after successfully established the chronic HE model (more than 28 days post-surgery). In addition, fecal samples collection and micro-PET/CT scans were performed sequentially. And we also collected the blood plasma, liver, intestinal, and brain samples after sacrificing the rats for further biochemical and pathological analyses. RESULTS: The RIF- and/or LAC-treated BDL rats showed similar behavioral results with Sham+NS group, while the treatment could not reverse the biliary obstruction resulting in sustained liver injury. The RIF or/and LAC treatments can inhibit IFN-γ and IL-10 productions. The global brain uptake values of [18F]PBR146 in BDL+NS group was significantly higher than other groups (p < .0001). The brain regions analysis showed that the basal ganglia, hippocampus, and cingulate cortex had radiotracer uptake differences among groups (all p < .05), which were consistent with the brain immunohistochemistry results. Sham+NS group was mainly enriched in Christensenella, Coprobacillus, and Pseudoflavonifractor. BDL+NS group was mainly enriched in Barnesiella, Alloprevotella, Enterococcus, and Enterorhabdus. BDL+RIF+LAC group was enriched in Parabacteroides, Bacteroides, Allobaculum, Bifidobacterium, and Parasutterella. CONCLUSIONS: RIF or/and LAC had anti-neuroinflammation in BDL-induced chronic HE rats with gut microbiota alterations. The [18F]PBR146 could be used for monitoring RIF or/and LAC treatment efficacy of chronic HE rats.

Efficacy and safety of infliximab and adalimumab in inflammatory bowel disease patients.

INTRODUCTION: Inflammatory bowel disease (IBD), consists of two primary types: Ulcerative Colitis (UC) and Crohn's Disease (CD). Infliximab (IFX) and Adalimumab (ADA) are frequently utilized in the management of moderate to severe cases of IBD. AIM: This study aimed to assess the efficacy and safety of IFX and ADA in individuals diagnosed with moderate to severe IBD. METHOD: This study is a prospective open-labeled randomized parallel study that included moderate to severe IBD patients treated with either IFX or ADA. A total of 56 patients participated, with 34 patients received IFX and 22 patients received ADA. Various measures, including Crohn's Disease Activity Index (CDAI), Mayo Score/ Disease Activity Index (DAI), and C-reactive protein (CRP) levels, were taken at baseline and week 14 to assess the efficacy of the treatments. In addition, the levels of drugs and sTREM-1 were measured at 14 weeks. Patient safety was monitored throughout the study period. RESULTS: In the group received IFX, there was a notable decrease in CDAI (P = 0.045), DAI (P = 0.026), and CRP (P = 0.023 for CD, and P = 0.021 for UC) levels. In addition, the group received ADA experienced a significant reduction in CDAI (P = 0.001), DAI (P = 0.032), and CRP (P < 0.018 for CD and P = 0.003 for UC) levels. Responders had higher drug concentrations than non-responders, notably IFX concentration was higher in responders with CD (P = 0.001) and UC (P < 0.001). ADA concentration was higher in UC (P <= 0.001) and all CD patients responded to the treatment. The same trend was observed for sTREM-1 levels in CD and UC patients (P = 0.042, and P = 0.015, respectively) in the IFX group. In UC patients treated with ADA, the level of sTREM-1 was significantly low (P = 0.002). CONCLUSION: Both IFX and ADA have a good safety profile and deliver a beneficial clinical and laboratory response in moderate-severe IBD patients. CLINICAL TRIAL REGISTRATION: This study is registered on ClinicalTrials.gov under the identifier NCT05291039. (You can access the study at https://clinicaltrials.gov/study/NCT05291039 (First Posted: March 22, 2022).

Colonic Epithelial Permeability to Ions Is Restored after Vedolizumab Treatment and May Predict Clinical Response in Inflammatory Bowel Disease Patients.

Vedolizumab (VDZ) is used for treating inflammatory bowel disease (IBD) patients. A study investigating colonic epithelial barrier function ex vivo following VDZ is lacking. This work aims to evaluate ex vivo the colonic epithelial barrier function in IBD patients at baseline and during VDZ treatment, and to investigate the relationships between barrier function and clinical parameters. Colonic specimens were obtained from 23 IBD patients before, and at 24 and 52 weeks after VDZ treatment, and from 26 healthy volunteers (HV). Transepithelial electrical resistance (TEER, permeability to ions) and paracellular permeability were measured in Ussing chambers. IBD patients showed increased epithelial permeability to ions (TEER, 13.80 ± 1.04 Ω × cm2 vs. HV 20.70 ± 1.52 Ω × cm2, p < 0.001) without changes in paracellular permeability of a 4 kDa probe. VDZ increased TEER (18.09 ± 1.44 Ω × cm2, p < 0.001) after 52 weeks. A clinical response was observed in 58% and 25% of patients at week 24, and in 62% and 50% at week 52, in ulcerative colitis and Crohn's disease, respectively. Clinical and endoscopic scores were strongly associated with TEER. TEER < 14.65 Ω × cm2 predicted response to VDZ (OR 11; CI 2-59). VDZ reduces the increased permeability to ions observed in the colonic epithelium of IBD patients before treatment, in parallel to a clinical, histological (inflammatory infiltrate), and endoscopic improvement. A low TEER predicts clinical response to VDZ therapy.

Infliximab modifies CD74-mediated lymphatic abnormalities and adipose tissue alterations in creeping fat of Crohn's disease.

BACKGROUND: Lymphatic abnormalities are essential for pathophysiologic changes of creeping fat (CrF) in Crohn's disease (CD). Anti-tumor necrosis factor (TNF) therapy has been proved to alleviate CrF lesions, however, whether it achieves these by remodeling lymphatics is unknown. METHODS: CD74 expression was detected in CrF and uninvolved mesentery of CD patients. Lymphatic functions in vitro were evaluated and lymphatic endothelium barrier were checked by transendothelial electrical resistance (TEER) and FITC-Dextran permeability. Protein level of tight junction and signaling pathways were detected by western blotting. RESULTS: CD74 was upregulated in LECs of CrF and positively correlated with TNF-α synthesis. This was suppressed by IFX administration. In vitro, TNF-α stimulated LECs to express CD74 through NF-κB signaling pathway, and this was rescued by IFX. CD74 downregulation suppressed the abilities of LECs in proliferation, migration and tube formation. Interaction of CD74-MIF impaired LECs' barrier via reducing tight junction proteins in an ERK1/2-dependent manner, which was reversed by CD74 downregulation. Consistently, the CD patients receiving IFX therapy displayed decreased lymphangiogenesis and improved mesenteric lymphatic endothelium barrier, companied with reduced adipocyte size and adipokine levels in CrF. CONCLUSIONS: Anti-TNF therapy could modify pathological changes in CrF by alleviating CD74-mediated lymphatic abnormalities.

Pharmacogenetics in IBS: update and impact of GWAS studies in drug targets and metabolism.

INTRODUCTION: Medications are frequently prescribed for patients with irritable bowel syndrome (IBS) or disorders of gut brain interaction. The level of drug metabolism and modifications in drug targets determine medication efficacy to modify motor or sensory function as well as patient response outcomes. AREAS COVERED: The literature search included PubMed searches with the terms: pharmacokinetics, pharmacogenomics, epigenetics, clinical trials, irritable bowel syndrome, disorders of gut brain interaction, and genome-wide association studies. The main topics covered in relation to irritable bowel syndrome were precision medicine, pharmacogenomics related to drug metabolism, pharmacogenomics related to mechanistic targets, and epigenetics. EXPERT OPINION: Pharmacogenomics impacting drug metabolism [CYP 2D6 (cytochrome P450 2D6) or 2C19 (cytochrome P450 2C19)] is the most practical approach to precision medicine in the treatment of IBS. Although there are proof of concept studies that have documented the importance of genetic modification of transmitters or receptors in altering responses to medications in IBS, these principles have rarely been applied in patient response outcomes. Genome-wide association (GWAS) studies have now documented the association of symptoms with genetic variation but not the evaluation of treatment responses. Considerably more research, particularly focused on patient response outcomes and epigenetics, is essential to impact this field in clinical medicine.

Comprehensive overview of novel chemical drugs for ulcerative colitis: focusing on phase 3 and beyond.

INTRODUCTION: Despite the growing number of highly efficacious biologics and chemical drugs for ulcerative colitis (UC), steroid-free disease control is still difficult to achieve in subgroups of patients due to refractoriness, adverse events, primary or secondary failure. New treatments are therefore still required in order to optimize clinical management of patients with UC. AREAS COVERED: The efficacy and safety of both currently available and newly developed small molecules have been summarized. The PubMed database and clinicaltrials.gov were considered in order to search for phase 2b and 3 trials on new chemical drugs for UC. The study drugs reviewed included Janus kinases (JAK) and sphingosine-1-phosphate receptor (S1Pr) inhibitors, α4 integrin antagonist, and micro-RNA-124 upregulators. EXPERT OPINION: Rapidity of onset, low immunogenicity, and safety are the main characteristics of small molecules currently available or under evaluation for treatment patients with UC. Among the currently available chemical drugs, the selective JAK and the S1Pr inhibitors are characterized by a good safety profile combined with the ability to induce clinical remission in UC. A relatively low frequency of endoscopic improvement and healing currently appears associated with their use, being higher in UC patients treated with S1Pr inhibitor Etrasimod. Overall, additional new safe and effective drugs are still required in order to optimize disease control in a larger majority of UC patients.

Current and emerging pharmacotherapy for the treatment of gastroparesis.

INTRODUCTION: Gastroparesis is a chronic disorder characterized by decreased gastric emptying and presents with nausea, vomiting, and abdominal pain which impacts patients' quality of life greatly. The treatment modalities available for gastroparesis have been expanding over the past 2 decades. Currently, there are multiple options available for gastroparesis, albeit with only one FDA-approved medication until June 2021. AREAS COVERED: We review the different treatments available for gastroparesis and discuss the recently FDA-approved intranasal formulation of metoclopramide. This nasal spray guarantees metoclopramide absorption within 15 min of application bypassing first pass metabolism in the liver and overcoming the limitations of the oral formulation not passing into the small intestine for absorption because of a gastroparetic stomach or a patient unable to take the oral metoclopramide because of nausea and vomiting. EXPERT OPINION: We now find ourselves in an oasis after spending many years in a 'desert' regarding pharmacologic therapies available for gastroparesis. The expansion of the research involving dopamine receptor antagonists and delving into alternative mechanisms of alleviating gastroparesis symptoms has been crucial in the landscape of gastroparesis. This is especially true as our knowledge of gastroparesis has proven that simply improving gastric emptying does not necessarily translate to clinical improvement.

Teduglutide improves liver chemistries in short bowel syndrome-associated intestinal failure: Post hoc analysis.

BACKGROUND: Chronic hepatic complications are common in patients with short bowel syndrome-associated intestinal failure (SBS-IF). Teduglutide, a glucagon-like peptide-2 analogue, demonstrated efficacy in reducing parenteral nutrition and/or intravenous fluid dependence among patients with SBS-IF in phase 3 clinical studies. METHODS: This was a post hoc analysis of pooled data from two separate randomized, double-blind, placebo-controlled, multinational phase 3 clinical studies. Adult patients with SBS-IF with parenteral nutrition and/or intravenous fluid dependence without liver disease at baseline were randomized to treatment with the glucagon-like peptide-2 analogue teduglutide (0.05 or 0.10 mg/kg/day) or placebo subcutaneously once daily for 24 weeks. Mixed-effects models assessed the baseline predictors of change in liver chemistries. RESULTS: Between baseline and week 24, teduglutide treatment (n = 109) was associated with least squares mean reductions in aspartate aminotransferase (-7.51 IU/L; P = 0.014), alanine aminotransferase (-12.15 IU/L; P = 0.002), and bilirubin (-5.03 µmol/L [-0.057 mg/dl]; P < 0.001) compared with that of the placebo (n = 59). These values were independent of reductions in parenteral nutrition and/or intravenous fluid dependence. CONCLUSION: Teduglutide treatment was associated with reductions in liver chemistries by week 24, which is beneficial for patients with SBS-IF beyond improvements in parenteral nutrition and/or intravenous fluid dependence. Future studies should examine how long-term teduglutide might mitigate the risk of liver disease in patients with SBS-IF.

Prokinetics-safety and efficacy: The European Society of Neurogastroenterology and Motility/The American Neurogastroenterology and Motility Society expert review.

BACKGROUND: Prokinetics are a class of pharmacological drugs designed to improve gastrointestinal (GI) motility, either regionally or across the whole gut. Each drug has its merits and drawbacks, and based on current evidence as high-quality studies are limited, we have no clear recommendation on one class or other. However, there remains a large unmet need for both regionally selective and/or globally acting prokinetic drugs that work primarily intraluminally and are safe and without systemic side effects. PURPOSE: Here, we describe the strengths and weaknesses of six classes of prokinetic drugs, including their pharmacokinetic properties, efficacy, safety and tolerability and potential indications.

Drugs of the future for diarrhea-predominant irritable bowel syndrome: an overview of current investigational drugs.

INTRODUCTION: Irritable bowel syndrome (IBS) has a significant impact on society and quality of life. Current treatments are ineffective, and new investigational drugs are necessary. AREAS COVERED: Numerous potential therapies are developing, targeting different areas such as cannabinoid signaling, opioid receptors, tachykinin (NK2) receptors, ß3-adrenergic receptors, intestinal microbiota, inflammation, and 5HT receptors. Clinical trial evidence has shown that loperamide, eluxadoline, alosetron, ramosetron, bile acid sequestrants, and rifaximin can modulate GI alterations and benefit patients with IBS-D. Among the potential therapies, ibodutant, ibudilast, blautix, BOS-589, solabegron, vibegron, olorinab, ebastine, and ORP-101 have demonstrated possible effects but remain confirmed. EXPERT OPINION: Individuals with IBS-D require cost-effective treatment options that do not impede their productivity or that of their caregivers. This is necessary for consistent healthcare and improved quality of life. Therefore, we should focus on developing new, efficient, and affordable medications for IBS-D. The government, insurers, and society must recognize this need and collaborate to ensure its fulfillment.

Association of CD4-positive cell infiltration with response to vedolizumab in patients with ulcerative colitis.

Not all patients with ulcerative colitis (UC) respond initially to treatment with biologic agents, and predicting their efficacy prior to treatment is difficult. Vedolizumab, a humanized monoclonal antibody against alpha 4 beta 7 (α4ß7) integrin, suppresses immune cell migration by blocking the interaction between α4ß7 integrin and mucosal addressin cell adhesion molecule 1. Reports about histological features that predict vedolizumab efficacy are scarce. So, we examined the association between histological features and vedolizumab efficacy. This was a multicenter, retrospective study of patients with UC treated with vedolizumab. Biopsy specimens taken from the colonic mucosa prior to vedolizumab induction were used, and the areas positively stained for CD4, CD68, and CD45 were calculated. Clinical and histological features were compared between those with and without remission at week 22, and the factors associated with clinical outcomes were identified. We enrolled 42 patients. Patients with a high CD4+ infiltration showed a better response to vedolizumab [odds ratio (OR) = 1.44, P = 0.014]. The concomitant use of corticosteroids and high Mayo scores had a negative association with the vedolizumab response (OR = 0.11, P = 0.008 and OR = 0.50, P = 0.009, respectively). Histological evaluation for CD4+ cell infiltration may be helpful in selecting patients who can benefit from vedolizumab.

Oral colon-targeted responsive alginate/hyaluronic acid-based hydrogel propels the application of infliximab in colitis.

Currently, commercialized infliximab (IFX) has rapidly propelled the clinical treatment of IBD, however, its inherent attributes, such as off-target effects and rapid metabolism, severely limit practical applications. Moreover, high doses injection of IFX can result in IBD treatment failure, which may induce other side effects. In this study, an colon microenvironment-responsive hydrogel (AL/HA hydrogel), consisting of acid-resistant sodium alginate and colon-degraded and targeted hyaluronic acid, was constructed by simple Ca2+/Zn2+ cross-linking. The ion-mediated hydrogel exhibited the protective effect of gastrointestinal tract to avoid early drug leakage, while the inflammation environments showed well-controlled drug release and significant biodegradable behaviors. Additionally, oral hydrogel exhibited long-standing enteritis areas compared with normal mice. Therefore, hydrogel-assisted enteritis treatment has great potential in IBD as an oral agent. After that, IFX was packaged in hydrogel to fabricate a facile oral antibody delivery system to treat IBD. IFX-embedded hydrogel showed remarkable therapeutic effect on IBD compared with free IFX. Surprisingly, oral hydrogel below 7 times IFX achieve the same amount of IFX-infused treatment that will further help alleviate the drawbacks of IFX. Our work elaborated on the efficacy of oral AL/HA@IFX in IBD, providing a guarantee for the future of promoted clinical transformation.

Ethnopharmacological basis and pharmacodynamics prospectives for folkloric claims of Rosa webbiana wall. Ex. Royle in diarrhea and asthma via In vitro, In vivo and In silico techniques.

ETHNOPHARMACOLOGICAL RELEVANCE: Rosa webbiana (Family: Rosaceae) is used by South Asian herbalists to treat gastrointestinal and respiratory disorders. AIM OF THE STUDY: This research aimed at multiple targets to verify R. webbiana for treating diarrhea and asthma. In vitro, in vivo, and in silico experiments were planned to demonstrate the antispasmodic and bronchodilator potential of R. webbiana. MATERIALS AND METHODS: The bioactive compounds of R. webbiana were identified and quantified through LC ESI-MS/MS and HPLC. These compounds were predicted for muti-mechanisms of bronchodilator and antispasmodic potential in network pharmacology and molecular docking. In vitro methods (isolated rabbit trachea, bladder, and jejunum tissues) confirmed these multi-mechanisms for antispasmodic and bronchodilator effects. Antiperistalsis, antidiarrheal, and antisecretory experiments were conducted in in-vivo experiments. RESULTS: The phytochemical analysis indicates the presence of rutin (742.91 µg/g), kaempferol (726.32 µg/g), and quercitrin (688.20 µg/g) in Rw. EtOH. These bioactive compounds in network pharmacology interfere with the pathogenic genes of diarrhea and asthma, which are the members of calcium-mediated signaling pathways and showed the stronger binding affinity towards voltage-gated L-type calcium channels, myosin light chain-kinase, Calcium calmodulin-dependent-kinase, Phosphodiesterase-4, and phosphoinositide phospholipase-C in molecular docking. Rw. EtOH elicited a spasmolytic response in isolated jejunum, trachea, and urine preparations by relaxing K+ (80 mM) and CCh (1 µM) spastic contractions. Additionally, it suppressed calcium concentration-response curves to the right, like verapamil. Like dicyclomine, it caused a rightward parallel shift of the CCh curves, followed by a non-parallel shift at higher concentrations with suppression of the maximal response. Like papaverine, it also caused isoprenaline-induced inhibitory CRCs to shift to the left. Verapamil did not potentiate isoprenaline-induced inhibitory CRCs, although it was more efficacious against K+ (80 mM) than CCh (1 µM)-induced contractions. R. webbiana EtOH extract exhibited complete antiperistalsis (21.55%), antidiarrheal (80.33%), and antisecretory (82.59±0.60) activities in vivo experiments at the dose of 300 mg/kg. CONCLUSION: Thus, Rw. EtOH modulated multiple pathways, produced calcium antagonistic, anticholinergic, and phosphodiesterase inhibitory actions, and had antidiarrheal and bronchodilator effects.

Responsiveness to Vedolizumab Therapy in Ulcerative Colitis is Associated With Alterations in Immune Cell-Cell Communications.

BACKGROUND: Ulcerative colitis (UC) and Crohn's disease are 2 types of inflammatory bowel disease (IBD), a group of chronic digestive disorders caused by aberrant immune responses to intestinal microbes. Although changes in the composition of immune cell subsets in the context of IBD have been previously described, the interactions and communication among cells are less well understood. Moreover, the precise mechanisms of action underlying many biologic therapies, including the anti-α4ß7 integrin antagonist vedolizumab, remain incompletely understood. Our study aimed to explore possible additional mechanisms through which vedolizumab acts. METHODS: We performed cellular indexing of transcriptomes and epitopes by sequencing (CITE-seq) on peripheral blood and colon immune cells derived from patients with ulcerative colitis treated with the anti-α4ß7 integrin antagonist vedolizumab. We applied a previously published computational approach, NicheNet, to predict immune cell-cell interactions, revealing putative ligand-receptor pairs and key transcriptional changes downstream of these cell-cell communications (CCC). RESULTS: We observed decreased proportions of T helper 17 (TH17) cells in UC patients who responded to vedolizumab and therefore focused the study on identifying cell-cell communications and signals of TH17 cells with other immune cells. For example, we observed that colon TH17 cells from vedolizumab nonresponders were predicted to have a greater degree of interactions with classical monocytes compared with responders, whereas colon TH17 cells from vedolizumab responders exhibited more interactions with myeloid dendritic cells compared with nonresponders. CONCLUSIONS: Overall, our results indicate that efforts to elucidate cell-cell communications among immune and nonimmune cell types may increase the mechanistic understanding of current and investigational therapies for IBD.

Compared to ulcerative patients unresponsive to vedolizumab, immune cell networks of ulcerative colitis patients responsive to vedolizumab have decreased proportion of TH17 and less pro-inflammatory signaling in the gut. Decreased pro-TH17 and interleukin (IL)-1 signaling from classical monocytes and innate immunocytes may mediate this phenotype.

Differential Effects of Ontamalimab Versus Vedolizumab on Immune Cell Trafficking in Intestinal Inflammation and Inflammatory Bowel Disease.

BACKGROUND AND AIMS: The anti-MAdCAM-1 antibody ontamalimab demonstrated efficacy in a phase II trial in ulcerative colitis and results of early terminated phase III trials are pending, but its precise mechanisms of action are still unclear. Thus, we explored the mechanisms of action of ontamalimab and compared it to the anti-α4ß7 antibody vedolizumab. METHODS: We studied MAdCAM-1 expression with RNA sequencing and immunohistochemistry. The mechanisms of action of ontamalimab were assessed with fluorescence microscopy, dynamic adhesion and rolling assays. We performed in vivo cell trafficking studies in mice and compared ontamalimab and vedolizumab surrogate [-s] antibodies in experimental models of colitis and wound healing. We analysed immune cell infiltration under anti-MAdCAM-1 and anti-α4ß7 treatment by single-cell transcriptomics and studied compensatory trafficking pathways. RESULTS: MAdCAM-1 expression was increased in active inflammatory bowel disease. Binding of ontamalimab to MAdCAM-1 induced the internalization of the complex. Functionally, ontamalimab blocked T cell adhesion similar to vedolizumab, but also inhibited L-selectin-dependent rolling of innate and adaptive immune cells. Despite conserved mechanisms in mice, the impact of ontamalimab-s and vedolizumab-s on experimental colitis and wound healing was similar. Single-cell RNA sequencing demonstrated enrichment of ontamalimab-s-treated lamina propria cells in specific clusters, and in vitro experiments indicated that redundant adhesion pathways are active in these cells. CONCLUSIONS: Ontamalimab has unique and broader mechanisms of action compared to vedolizumab. However, this seems to be compensated for by redundant cell trafficking circuits and leads to similar preclinical efficacy of anti-α4ß7 and anti-MAdCAM-1 treatment. These results will be important for the interpretation of pending phase III data.

Anti-ß7 integrin treatment impedes the recruitment on non-classical monocytes to the gut and delays macrophage-mediated intestinal wound healing.

BACKGROUND: Closing mucosal defects to reach mucosal healing is an important goal of therapy in inflammatory bowel disease (IBD). Among other cells, monocyte-derived macrophages are centrally involved in such intestinal wound healing. We had previously demonstrated that the anti-α4ß7 integrin antibody vedolizumab blocks the recruitment of non-classical monocytes as biased progenitors of wound healing macrophages to the gut and delays wound healing. However, although important for the interpretation of disappointing results in recent phase III trials in IBD, the effects of the anti-ß7 antibody etrolizumab on wound healing are unclear so far. METHODS: We analyzed the expression of etrolizumab targets on human and mouse monocyte subsets by flow cytometry and assessed their function in adhesion and homing assays. We explored wound-associated monocyte recruitment dynamics with multi-photon microscopy and compared the effects of etrolizumab and vedolizumab surrogate (-s) antibodies on experimental wound healing and wound-associated macrophage abundance. Finally, we investigated wound healing macrophage signatures in the large intestinal transcriptome of patients with Crohn's disease treated with etrolizumab. RESULTS: Human and mouse non-classical monocytes expressed more αEß7 integrin than classical monocytes and were a target of etrolizumab-s, which blocked non-classical monocyte adhesion to MAdCAM-1 and E-Cadherin as well as gut homing in vivo. Intestinal wound healing was delayed on treatment with etrolizumab-s along with a reduction of peri-lesional wound healing macrophages. Wound healing macrophage signatures in the colon of patients with Crohn's disease were substantially down-regulated on treatment with etrolizumab, but not with placebo. CONCLUSIONS: Combined blockade of αEß7 and α4ß7 with etrolizumab seems to exceed the effect of anti-α4ß7 treatment on intestinal wound healing, which might help to inform further investigations to understand the recent observations in the etrolizumab phase III trial program.

Infliximab response associates with radiologic findings in bio-naïve Crohn's disease.

OBJECTIVES: Since a reliable model for predicting infliximab (IFX) benefits in bio-naïve Crohn's disease (CD) is still lacking, we constructed a magnetic resonance enterography (MRE)-based model to predict the risk of loss of response to IFX in bio-naïve patients with CD. METHODS: This retrospective multicenter study enrolled 188 bio-naïve patients with CD who underwent MRE before IFX therapy. Therapeutic outcomes were determined based on clinical symptoms and endoscopic findings within 52 weeks. The areas of bowel wall segmentation were decided by two experienced radiologists in consensus. Texture features were extracted using the least absolute shrinkage and selection operator, and a radiomic model was built using multivariate logistic regression. The model performance was validated by receiver operating characteristic, calibration curve, and decision curve analysis. RESULTS: The area under the curve of radiomic model was 0.88 (95% confidence interval: 0.82-0.95), and the model provided clinical net benefit in identifying the loss of response to IFX and exhibited remarkable robustness among centers, scanners, and disease characteristics. The high-risk patients defined by the radiomic model were more likely to develop IFX nonresponse than low-risk patients (all p < 0.05). CONCLUSIONS: This novel pretreatment MRE-based model could act as an effective tool for the early estimation of loss of response to IFX in bio-naïve patients with CD. KEY POINTS: • Magnetic resonance enterography model guides infliximab therapy in Crohn's disease. • The model presented significant discrimination and provided net clinical benefit. • Model divided patients into low- and high-risk groups for infliximab failure.