Is there a role for vedolizumab in the treatment of ulcerative colitis and Crohn's disease?

The role of integrins in the pathogenesis of inflammatory bowel disease: Approved and investigational anti-integrin therapies

Inflammatory bowel disease (IBD) is characterized by uncontrolled inflammation in the gastrointestinal tract. The underlying pathobiology of IBD includes an increase in infiltrating gut-homing lymphocytes. Although lymphocyte homing is typically a tightly regulated and stepwise process involving multiple integrins and adhesion molecules expressed on endothelial cells, the distinct roles of integrin-expressing immune cells is not fully understood in the pathology of IBD. In this review, we detail the involvement of integrins expressed on specific lymphocyte subsets in the pathogenesis of IBD and discuss the current status of approved and investigational integrin-targeted therapies.

Activating the pregnane X receptor by imperatorin attenuates dextran sulphate sodium-induced colitis in mice

BACKGROUND AND PURPOSE

Activation of the human pregnane X receptor (PXR; NR1I2) has potential therapeutic uses for inflammatory bowel disease (IBD). Imperatorin (IMP), a naturally occurring coumarin, is the main bioactive ingredient of Angelica dahurica Radix, which is regularly used to treat the common cold and intestinal disorders. However, there are no data on the protective effects of IMP against IBD.

EXPERIMENTAL APPROACH

The effects of IMP on PXR-modulated cytochrome P450 3A4 (CYP3A4) expression were assessed using a PXR transactivation assay, a mammalian two-hybrid assay, a competitive ligand-binding assay, analysis of CYP3A4 mRNA and protein expression levels and measurement of CYP3A4 activity using a cell-based reporter gene assay and in vitro model. The inhibitory effects of IMP on NF-κB activity were evaluated by a reporter assay and NF-κB p65 nuclear translocation. The anti-IBD effects of IMP were investigated in a dextran sulphate sodium (DSS)-induced colitis mouse model. Colon inflammatory cytokines were assessed by elisa.

KEY RESULTS

IMP activated CYP3A4 promoter activity, recruited steroid receptor coactivator 1 to the ligand-binding domain of PXR and increased the expression and activity of CYP3A4. PXR knockdown substantially reduced IMP-induced increase in CYP3A4 expression. Furthermore, IMP-mediated PXR activation suppressed the nuclear translocation of NF-κB and down-regulated LPS-induced expression of pro-inflammatory genes. Nevertheless, PXR knockdown partially reduced the IMP-mediated inhibition of NF-κB. IMP ameliorated DSS-induced colitis by PXR/NF-κB signalling.

CONCLUSIONS AND IMPLICATIONS

IMP acts as a PXR agonist to attenuate DSS-induced colitis by suppression of the NF-κB-mediated pro-inflammatory response in a PXR/NF-κB-dependent manner.

Intestinal inflammation and the diet: Is food friend or foe?

Inflammatory bowel disease (IBD) is a chronic intestinal illness of autoimmune origin affecting millions across the globe. The most common subtypes include ulcerative colitis (UC) and Crohn’s disease. While many medical treatments for IBD exist, none come without the risk of significant immunosuppression and in general do not have benign side effect profiles. Surgical intervention exists only as radical resection for medically refractory UC. There exists a dire need for novel treatments that target the inherent pathophysiologic disturbances of IBD, rather than global immune suppression. One avenue of investigation that could provide such an agent is the interaction between certain dietary elements and the aryl hydrocarbon receptor (AHR). The AHR is a cytosolic transcription factor with a rich history in environmental toxicant handling, however, recently a role has emerged for the AHR as a modulator of the gastrointestinal immune system. Studies have come to elucidate these effects to include the enhancement of T_h cell subset differentiation, interactions between enteric flora and the luminal wall, and modulation of inflammatory interleukin and cytokine signaling. This review highlights advancements in our understanding of AHR activity in the digestive tract and how this stimulation may be wrought by certain dietary “micronutriceuticals”, namely indole-3-carbinol (I3C) and its derivatives. Greater clarity surrounding these dynamics could lead to a novel diet-derived agonist of the AHR which is not only non-toxic, but also efficacious in the amelioration of clinical IBD.

Efficacy of Vedolizumab as Induction Therapy in Refractory IBD Patients: A Multicenter Cohort

BACKGROUND

Vedolizumab (VDZ) demonstrated efficacy in Crohn's disease (CD) and ulcerative colitis (UC) in the GEMINI trials. Our aim was to evaluate the efficacy of VDZ at week 14 in inflammatory bowel disease in a multicenter cohort of patients.

METHODS

Patients at Massachusetts General Hospital and Brigham and Women's Hospital were considered for inclusion. VDZ (300 mg) was administered at weeks 0, 2, 6, and 14. Efficacy was assessed using the Harvey-Bradshaw index for CD, the simple clinical colitis activity index for UC and physician assessment, along with C-reactive protein and decrease of corticosteroid therapy. Clinical response was defined as decrease in Harvey-Bradshaw index ≥3 and simple clinical colitis activity index ≥3 and remission as Harvey-Bradshaw index ≤4, simple clinical colitis activity index ≤2 and physician assessment of response and remission.

RESULTS

Our study included 172 patients (107 CD, 59 UC, 6 inflammatory bowel disease-unclassified, men 48.3%, mean age 40 years and disease duration 14 years). Fourteen patients had ostomy and 9 ileoanal pouch, and only 35.5% fulfilled eligibility for the GEMINI trials. Previous treatment failures with ≥ 2 anti-TNFs occurred in 70.9%, one-third were on an immunomodulator and 46% systemic steroids at baseline. In CD, 48.9% and 23.9% and in UC, 53.9% and 29.3% had clinical response and clinical remission at week 14, respectively. Adverse events occurred in 10.5%.

CONCLUSIONS

VDZ is safe and well tolerated in refractory inflammatory bowel disease patients in a clinical practice with efficacy in UC and CD with responses similar to what was seen in clinical trials.

Patient considerations in the management of ulcerative colitis - role of vedolizumab

Ulcerative colitis (UC) is a subtype of inflammatory bowel disease which causes inflammation of the large intestine and affects approximately 7.6–24.6 per 100,000 persons. The therapeutic goal for UC patients is inducing remission, maintaining remission, and ideally, obtaining mucosal healing. Vedolizumab, approved by the US Food and Drug Administration in May 2014 for the treatment of moderate-to-severe UC and Crohn’s disease, is a newly developed anti-integrin therapy. This review focuses on the preclinical development of vedolizumab and data from early trials, and details the results of the landmark trails that led to its approval in the USA with a specific focus on the management of UC. Additionally, data on safety and the current UC management protocols are also discussed.

New pharmaceuticals in inflammatory bowel disease

This paper complements the previously published Guidelines of the Working Group of the Polish Society of Gastroenterology and former National Consultant in Gastroenterology regarding the management of patients with Crohn's disease and ulcerative colitis. Attention was focused on the new pharmaceutical recently registered for inflammatory bowel disease treatment.

Infliximab is superior to other biological agents for treatment of active ulcerative colitis: A meta-analysis

AIM: To compare the efficacy and safety of biological agents for the treatment of active ulcerative colitis (UC).

METHODS: PubMed, MEDLINE, EMBASE and the Cochrane library were searched to screen relevant articles from January 1996 to August 2014. The mixed treatment comparison meta-analysis within a Bayesian framework was performed using WinBUGS14 software. The proportions of patients reaching clinical response, clinical remission and mucosal healing in induction and maintenance phases were analyzed as efficacy indicators. Serious adverse events in maintenance phase were analyzed as safety indicators.

RESULTS: The meta-analysis results showed that biological agents achieved better clinical response, clinical remission and mucosal healing than placebo. Indirect comparison indicated that in induction phase, infliximab was more effective than adalimumab in inducing clinical response (OR = 0.41, 95%CI: 0.29-0.57), clinical remission (OR = 0.33, 95%CI: 0.19-0.56) and mucosal healing (OR = 0.33, 95%CI: 0.19-0.56), and golimumab in inducing clinical response (OR = 0.66, 95%CI: 0.39-2.33) and mucosal healing (OR = 2.15, 95%CI: 1.18-4.22). No significant difference was found between placebo and biological agents regarding their safety.

CONCLUSION: All biological agents were superior to placebo for UC treatment in both induction and maintenance phases with a similar safety profile, and infliximab had a better clinical effect than the other biological agents.

New Trends in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic idiopathic inflammatory disease of the gastrointestinal (GI) tract. In the past decade a shift in the treatment paradigm of IBD has ensued. The availability of drugs capable of inducing mucosal healing, combined with the recognition that IBD is not an intermittent disease, but rather a progressive one causing bowel damage and disability, led us to a more stringent strategy. Tailored therapy with more aggressive treatment in high-risk patients, treating beyond symptoms, intervening early before damage occurs, optimizing therapeutic regimens, and actively pursuing sustained remission and sustained control of inflammation are strategies that are slowly being incorporated in our clinical practice. Furthermore, new drugs targeting different immunological pathways, such as vedolizumab, have recently been approved and therefore more therapeutic resources for patients failing anti-tumour necrosis factor alpha (anti-TNFα) agents will be available. The future years look promising for IBD. Hopefully the new trends in IBD management, combined with new drugs, will make possible to change the course of disease and provide better therapy and quality of life for patients suffering from this disabling disease.

Integrin antagonists are effective and safe for Crohn’s disease: A meta-analysis

AIM: To evaluate the efficacy and safety of integrin antagonists, including natalizumab and vedolizumab, in Crohn’s disease (CD).

METHODS: We carried out a literature search in PubMed, MEDLINE, EMBASE and the Cochrane Library to screen for citations from January 1990 to August 2014. Data analysis was performed using Review Manager version 5.2.

RESULTS: A total of 1340 patients from five studies were involved in this meta-analysis. During 6-12 wk treatment, integrin antagonists increased the rate of clinical response and remission with OR = 1.69, 95%CI: 1.37-2.09 and 1.84, 95%CI: 1.44-2.34, respectively. No significant difference was found between integrin antagonists and placebo treatments regarding their adverse reactions (OR = 1.07, 95%CI: 0.83-1.38) and serious adverse reactions (OR = 0.81, 95%CI: 0.57-1.15).

CONCLUSION: The results prove the efficacy and safety of integrin antagonists for CD treatment, although the treatment strategies varied.

Efficacy and safety of antiintegrin antibody for inflammatory bowel disease: a systematic review and meta-analysis

We sought to evaluate the safety and efficacy of available biologics that inhibit T-cell migration by blocking α4β7 integrins in inflammatory bowel diseases. The aim of this study is to evaluate whether Crohn disease (CD) patients receiving either vedolizumab or natalizumab have any different effect in CD Activity Index (CDAI). Using Medline, Excerpta Medica dataBASE, Cochrane Central Register of Controlled Trials (CENTRAL), and Google Scholar until October 31, 2013, we identified 10 studies examining the safety and efficacy of specific integrin inhibitors—vedolizumab, which targets an epitope comprising the α4β7 heterodimer; natalizumab, which recognizes the α4 integrin subunit; etrolizumab, which is specific for the β7 subunit—in the treatment of CD and ulcerative colitis (UC). CD patients receiving either vedolizumab or natalizumab demonstrated a modest increase in remission rate, when compared with that of the placebo group. Further, although both treatments reduced the CDAI slightly, the observed clinical response was less robust than that of the remission rate. UC patients treated with vedolizumab and natalizumab were found to show more prominent increases in both remission and clinical response, compared with placebo, than patients with CD. Etrolizumab, however, was not found to significantly affect either response or remission rates in UC patients. Biologics targeting integrins show promise as therapeutics in the treatment of inflammatory bowel disease in patients who are either nonresponsive or intolerant to traditional approaches, though further research is necessary to optimize treatment efficacies.

The th17/treg immune balance in ulcerative colitis patients with two different chinese syndromes: dampness-heat in large intestine and spleen and kidney yang deficiency syndrome

Objective. To investigate the Th17/Treg immune balance in the ulcerative colitis (UC) patients with two Chinese syndrome: dampness-heat in large intestine (DHLI) and spleen and kidney Yang deficiency (SKYD). Methods. Ninety UC patients (45 were diagnosed with DHLI and 45 with SKYD syndrome) and 23 healthy people were recruited. The serumIL-17 and TGF-β1 levels of these participants were measured with ELISA; the expression of IL-17 and TGF-β 1 in colonic mucosa tissue was determined with immunohistochemistry and the percentage of Th17 and Treg in peripheral blood with flow cytometry. Results. The levels of IL-17 and Th17 were significantly higher in both DHLI and SKYD groups than in healthy control group and higher in DHLI than in SKYD group (P < 0.05). The levels of TGF-β1 and Treg were significantly lower in the two UC patients groups than in healthy control group; and lower in SKYD group than in DHLI group (P < 0.05). Conclusions. UC with DHLI syndrome could be characterized by the elevation of Th17 and IL-17 levels, which indicated an accentuation of inflammatory reaction; UC with SKYD syndrome could be characterized by the reduction of serum Treg and TGF-β1 levels, which represented a depression of immune tolerance.

Notoginsenoside R1 attenuates experimental inflammatory bowel disease via pregnane X receptor activation

Notoginsenoside R1 (R1) is the main bioactive component in Panax notoginseng, an old herb medicine widely used in Asian countries in the treatment of microcirculatory diseases. However, little is known about the effect of R1 on inflammatory bowel disease (IBD). The present study demonstrated that R1 alleviated the severity of dextran sulfate sodium-induced colitis in mice by decreasing the activity of myeloperoxidase, the production of cytokines, the expression of proinflammatory genes, and the phosphorylation of IκB kinase, IκBα, and p65 in the colon. Further studies indicated that R1 dose-dependently activated human/mouse pregnane X receptor (PXR), a known target for decreasing inflammation in IBD, and upregulated the expression of genes involved in xenobiotic metabolism in colorectal cells and the colon. Ligand pocket-filling mutant (S247W/C284W or S247W/C284W/S208W) of the human PXR abrogated the effect of R1 on PXR activation. Time-resolved fluorescence resonance energy transfer PXR competitive binding assay confirmed R1 (ligand) binding affinity. In addition, PXR overexpression inhibited nuclear factor-κB (NF-κB)-luciferase activity, which was potentiated by R1 treatment. PXR knockdown by small interfering RNA demonstrated the necessity of PXR in R1-induced upregulation of the expression of xenobiotic-metabolizing enzymes and downregulation of NF-κB activity. Finally, the anti-inflammatory effect of R1 was confirmed in trinitrobenzene sulfonic acid-induced colitis in mice. These findings suggest that R1 attenuates experimental IBD possibly via the activation of intestinal PXR signaling.