Efficacy of biological therapies in inflammatory bowel disease: systematic review and meta-analysis

TNFα and IL-17 cooperatively stimulate glucose metabolism and growth factor production in human colorectal cancer cells

Background

Inflammation is a well-known etiological factor for colorectal cancer, but mechanisms underlying the linkage between inflammation and cancer are incompletely understood. We hypothesized that two pro-inflammatory cytokines, TNFα and IL-17, might play a role in promoting colorectal carcinogenesis. Aerobic glycolysis is a metabolic adaptation that promotes the survival/proliferation of cancer cells. Paracrine signaling between tumor cells and cancer-associated fibroblasts also plays a role in carcinogenesis.

Methods

The effect of TNFα and IL-17 on aerobic glycolysis and growth factor production in cultured human colorectal cancer cells was investigated. Glucose utilization and lactate production were quantified by measuring the disappearance of glucose and appearance of lactate in the culture medium. Glucose transporter and glycolytic enzyme expression levels were measured by immunoblotting.

Results

TNFα and IL-17 cooperatively stimulated glycolysis in HT-29, T84, Caco-2 and HCT116 colorectal cancer cells. Treatment of HT-29 cells with TNFα plus IL-17 also increased the expression of HIF-1α and c-myc, two factors know to induce the transcription of genes encoding components of the glycolytic pathway. To further investigate mechanisms for cytokine-stimulated glycolysis, the effects of TNFα and IL-17 on expression of six members and one regulator of the glycolytic pathway were investigated. TNFα and IL-17 cooperatively increased the expression of the glucose transporter SLC2A1 and hexokinase-2 but did not regulate expression of glucose transporter SLC2A3, enolase-1, pyruvate kinase M2, lactate dehydrogenase A, or 6-phoshofructo-2-kinase/fructose-2,6-bisphosphatase-3 (PFKFB3). Experiments with inhibitors indicated that HIF-1α played a role in induction of SLC2A1 and that the transcription factor NF-κB played a role in induction of hexokinase-2 by TNFα and IL-17. TNFα and IL-17 also synergistically stimulated production by HT-29 cells of a growth factor that simulated proliferation/survival of NIL8 fibroblastic cells. The activity of this factor was not specifically inhibited by the EGFR inhibitor AG1478, indicating that it is not an EGFR ligand.

Conclusions

Chronic inflammation is known to promote colorectal tumorigenesis. The pro-inflammatory cytokines TNFα and IL-17 may contribute to this effect by stimulating glycolysis and growth factor production in colorectal cancer cells.

A rapid assay for on-site monitoring of infliximab trough levels: a feasibility study

Monitoring levels of biologicals against tumor necrosis factor (TNF) has been suggested to improve therapeutic outcomes in inflammatory bowel diseases (IBDs). This pilot study describes a rapid lateral flow (LF)-based assay for on-site monitoring of serum trough levels of humanized monoclonal antibody infliximab (IFX). The applied chromatographic method utilizes sequential flows of diluted serum, wash buffer, and an immunoglobulin generic label on LF strips with a Test line comprised of TNF-α. The successive flows permitted enrichment of IFX at the Test line before the label was applied. The label, luminescent upconverting phosphor (UCP) particles coated with protein-A, emits a 550-nm visible light upon excitation with 980-nm infrared light. IFX concentrations were determined through measurement of UCP fluorescence at the Test line. The assay was optimized to detect IFX levels as low as 0.17 μg/mL in serum. For patients with IBD, this limit is appropriate to detect levels associated with loss of response (0.5 μg IFX/mL). The assay was evaluated with clinical samples from patients with Crohn's disease and correlated well within the physiologically relevant range from 0.17 to 10 μg/mL with an IFX-specific ELISA. Performance of the assay was further successfully validated with samples from blood donors, IFX negative IBD patients, and rheumatoid arthritis patients that had developed anti-IFX antibodies. Because of its generic nature, the assay is suited for detecting most therapeutic anti-TNF-α monoclonal antibodies.

Top-down or step-up treatment in Crohn's disease?

In recent years, a change in the treatment goals for patients with Crohn's disease (CD) has come under intense discussion. Whereas 10 years ago treatment was initiated mainly in reaction to acute flares of the disease aimed to improve clinical symptoms, the focus now has changed to the prevention of damage to the intestinal wall. The prevention of structural damage by achievement of 'mucosal healing', however, is associated with the more 'aggressive' treatment and an earlier use of immunosuppressants and biologicals. The use of immunosuppressants and biologicals especially in patients with CD has decreased the rates of surgery and hospitalizations, indicating that there is a group of patients definitely profiting from such an early use of immunosuppressive treatment. In this group of patients, the benefits outweigh the disadvantages of immunosuppression: the increased risk of severe infections. However, it remains questionable whether this improvement can only be achieved by completely reversing established treatment strategies. The dispute has been condensed to the questions whether 'top-down' (e.g. start with a combination of biological and immunosuppressant and 'de-escalate' if possible) or 'step-up' treatment (e.g. start with topical steroids, step up to systemic steroid, go to immunosuppression and biologicals if necessary) may be better. In general, in an upcoming era of individualized and personalized medicine, a 'one-size-fits-all' approach does not appear to be desirable. CD patients definitely should not be undertreated (which is still frequently the case) or remain on steroid treatment (which is inappropriate); however, overtreatment (putting patients at risk of side effects without benefit) is against a fundamental principle of medicine: nihil nocere (do no harm).

Targets for new immunomodulation strategies in inflammatory bowel disease

Crohn's disease (CD) and ulcerative colitis (UC), the major forms of inflammatory bowel diseases (IBD) in human beings, are characterized by damage to the intestinal epithelium and deeper layers, which is caused by an excessive immune response directed against normal constituents of the gut microflora. In both IBD, the diseased tissue is heavily infiltrated with several subsets of leukocytes that produce huge amounts of inflammatory cytokines whose profiles varies not only between CD and UC but also during the evolution of the same disease. These recent discoveries together with the demonstration that the inhibition of some soluble cytokines is not beneficial in IBD have contributed to delineate new scenarios by which tissue damage is induced and perpetuated. We here review some of the major immunological defects documented in IBD and discuss why compounds inhibiting soluble cytokines were not beneficial in patients and how we can optimize therapeutic strategies with biologics.

Pre-existing IgG antibodies cross-reacting with the Fab region of infliximab predict efficacy and safety of infliximab therapy in inflammatory bowel disease

BACKGROUND

Infliximab (IFX) is a chimeric murine/human anti-TNF antibody (Ab) used for the treatment of Crohn's disease (CD) and ulcerative colitis (UC). Loss of response is common and associated with development of anti-IFX Abs during ongoing therapy. However, human anti-murine immunoglobulin Abs are common and may cross-react with the murine part of IFX.

AIM

To investigate if Abs binding to IFX's Fab region (IFX-Fab) are present in IBD patients before exposure to IFX, and whether they predict efficacy and safety of IFX therapy.

METHODS

Observational, retrospective cohort study of patients with CD (n = 29) and UC (n = 22).

RESULTS

Pre-treatment levels of IFX-Fab reactive IgG Abs were significantly lower in CD patients in remission after 1 year of maintenance IFX (median 91 mU/L, n = 8) than in the rest of the patients (639 mU/L, n = 21; P < 0.01), and lower than in patients with secondary loss of response in particular (692 mU/L, n = 7; P < 0.01). A cut-off concentration of <439 mU IFX-Fab reactive IgG Ab per litre comprised all patients who later obtained long-term sustained remission on IFX (sensitivity 100%, specificity 67%). Similar trends were observed in UC. The pre-treatment levels of IFX-Fab reactive IgG Abs were markedly higher in patients developing infusion reactions to IFX (1037 mU/L, n = 7) than in the remaining patients (349 mU/L, n = 44; P = 0.036).

CONCLUSIONS

IFX-Fab reactive IgG antibodies present in serum from IBD patients before infliximab therapy associate with lack of long-term efficacy and safety. Assessments of such antibodies may help clinicians to choose between treatment with infliximab and more humanised agents.

Recent developments in the treatment of inflammatory bowel disease

Crohn's disease and ulcerative colitis are chronic inflammatory bowel diseases that have been treated with corticosteroids, 5-aminosalicates and thiopurines, but therapeutic options have been broadened with the arrival of anti-tumor necrosis factor antibodies. In this article we reviewed the current evidence-based approach to inflammatory bowel disease, the modifications that have been made to existing therapies and discussed new drugs that have shown success in clinical trials. The new drugs discussed here are those that disturb lymphocyte homing to the gut (natalizumab, vedolizumab and anti-mucosal addressin cellular adhesion molecule); one that blocks interleukin (IL)-12 as well as the IL-23/T helper 17 (Th17) axis (ustekinumab) and one that blocks the signaling of multiple cytokines (tofacitinib).

New targeting strategies in drug therapy of inflammatory bowel disease: mechanistic approaches and opportunities

INTRODUCTION

Inflammatory bowel disease (IBD) is an exceptional scenario with regard to drug targeting, as oral administration has the potential to deliver the drug directly to the site(s) of action. Consequently, retention of the drug within the intestinal lumen and tissue, rather than systemic absorption, is frequently desirable.

AREAS COVERED

In this article, the traditional drug-delivery strategies used in IBD are briefly summarized. These include rectal dosage forms and oral systems that target the lower intestine/colon by pH-, time-, microflora-, and pressure-dependent mechanisms. Then, the article offers an updated overview of recently developed delivery systems aimed to achieve maximal drug concentrations in the inflamed intestinal tissues with minimal systemic side effects. These include antibodies, small molecules, Janus kinase inhibitors, particulate carrier systems, anti-inflammatory peptides, gene therapy, and transgenic bacteria. The various approaches are reviewed, and the challenges that still remain to be overcome are discussed.

EXPERT OPINION

The molecular revolution of the past decade profoundly influenced the treatment and management of IBD. In the coming years, this trend is expected to continue. Yet, many challenges are still ahead. A strong collaborative effort by experts from different fields is encouraged and necessary to maximize our success in IBD drug targeting.

Ulcerative colitis: prevention of relapse

The clinical management of ulcerative colitis (UC) involves first treating the acute symptoms to induce remission, and then successfully maintaining it. Oral 5-aminosalicylic acids are safe and useful for maintaining remission in patients with UC. In terms of adherence, a once-daily form of 5-aminosalicylic acid is superior in maintaining remission as compared with split dosing. Patients at high risk of relapse may be candidates for treatment with thiopurines and/or biologics in the early stages of UC. Calcineurin inhibitors, such as cyclosporine and tacrolimus, are effective for severe, steroid-refractory UC patients. It is suggested that these patients use thiopurines as their maintenance therapy once they achieve remission with calcineurin inhibitors. Recent studies have confirmed that biologics are effective for inducing clinical and endoscopic remission of UC, and thus they may improve long-term prognosis of UC.

Efficacy and safety of certolizumab pegol for Crohn's disease: a systematic review and meta-analysis

INTRODUCTION

The authors performed a systematic review and meta-analysis of data from randomized controlled trials (RCTs) to evaluate the efficacy and safety of certolizumab pegol.

METHODS

The authors searched PubMed, MEDLINE via Medscape, BioMed Central, Google Scholar, China National Knowledge Infrastructure (CNKI), the Cochrane library, and the Directory of Open Access Journals. The outcomes of interest were response and remission rates and the treatment-related toxicity rate.

RESULTS

A total of five RCTs, involving 1,891 participants, were included. The meta-analysis revealed that certolizumab significantly increased the overall (induction + maintenance therapy) response [odds ratio (OR) 1.565, 95% CI 1.056-2.321, P = 0.026] and remission rates (OR 1.626, 95% CI 1.297-2.038, P < 0.001) compared with placebo. Certolizumab significantly increased the response and remission rates when given as maintenance therapy (OR 2.171, 95% CI 1.644-2.866, P < 0.001 and OR 1.888, 95% CI 1.390-2.565, P < 0.001), but not as induction therapy (OR 1.234, 95% CI 0.912-1.671, P = 0.173 and OR 1.361, 95% CI 0.974-1.901, P = 0.071). Certolizumab (induction + maintenance therapy) did not significantly increase the treatment-related toxicity rate compared with placebo (OR 0.985, 95% CI 0.799-1.214, P = 0.887).

CONCLUSION

Certolizumab may be an efficacious treatment for Crohn's disease as maintenance therapy and appears to have a favorable safety profile.

Clinical use of anti-TNF therapy and increased risk of infections

Biologics such as antitumor necrosis factor (anti-TNF) drugs have emerged as important agents in the treatment of many chronic inflammatory diseases, especially in cases refractory to conventional treatment modalities. However, opportunistic infections have become a major safety concern in patients on anti-TNF therapy, and physicians who utilize these agents must understand the increased risks of infection. A literature review of the published data on the risk of bacterial, viral, fungal, and parasitic infections associated with anti-TNF therapy was performed and the clinical presentation, diagnostic tests, management, and prevention of opportunistic infections in patients receiving anti-TNF therapy were reviewed. Awareness of the therapeutic potential and associated adverse events is necessary for maximizing therapeutic benefits while minimizing adverse effects from anti-TNF treatments. Patients should be adequately vaccinated when possible and closely monitored for early signs of infection. When serious infections occur, withdrawal of anti-TNF therapy may be necessary until the infection has been identified and properly treated.

Promising effect of Magliasa, a traditional Iranian formula, on experimental colitis on the basis of biochemical and cellular findings

AIM: To investigate the efficacy of Magliasa, a traditional Iranian formula, on experimental colitis.

METHODS: After botanical authentication of herbal ingredients, formulation of Magliasa, quantitative determination of total glucosinolates and total phenolic content, and analysis of the thin layer chromatography profile were performed. Colitis was then induced in male rats by instillation of 2,4,6-trinitrobenzenesulfonic acid (TNBS) in all groups, aside from the Sham group. The experimental groups consisted of: the Sham group that received only normal saline; the Mag-50, Mag-100 and Mag-200 groups, which received 50, 100 and 200 mg/kg per day of Magliasa, respectively; the control group, which received vehicle water orally; the infliximab group, which received infliximab (5 mg/kg per day, subcutaneously); and the Dexa group, which received dexamethasone (1 mg/kg per day, orally). After completing the treatment period (2 wk), the rats were sacrificed, the colon was removed, its macroscopic and microscopic changes were recorded, and tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), total antioxidant capacity, myeloperoxidase (MPO), and lipid peroxidation (LPO) were assessed in colon homogenate.

RESULTS: The mean value of total glucosinolates in one gram of Magliasa was 19 ± 1 μmol. The mean value of the total phenolic content was 293.8 ± 17.6 mg gallic acid equivalents per 100 gram of Magliasa. Macroscopic scores were significantly decreased in Mag-100 (1.80 ± 0.58, P = 0.019) and Mag-200 (1.20 ± 0.20, P = 0.001) compared to the control group (3.40 ± 0.24), although some inflammation and hyperemia were evident. Treatment of rats by dexamethasone (0.33 ± 0.21, P < 0.001) and infliximab (0.83 ± 0.31, P < 0.001) remarkably attenuated scores where mild hyperemia was observed macroscopically. In comparison to the control group (4.00 ± 0.32), only Mag-200 (1.60 ± 0.40) showed a significant decrease in colonic histopathological scores (P = 0.005). Minimal mucosal inflammation was observed in the Dexa group (0.67 ± 0.21, P < 0.001). The levels of TNF-α, IL-1β and MPO were significantly lower in all groups compared to the controls (P < 0.05). A significant decrease in LPO was seen in the Mag-200 (3.27 ± 0.77, P = 0.01) and Dexa (3.44 ± 0.22, P = 0.011) groups in comparison to the control group (6.43 ± 0.61). Only dexamethasone caused a significant increase in antioxidant power in comparison to the control group (346.73 ± 9.9 vs 228.33 ± 2.75, P < 0.001). Infliximab and different doses of Magliasa did not show any remarkable increase in antioxidant capacity (P > 0.05). The effect of Magliasa in all of mentioned parameters, except antioxidant capacity, was dose dependent.

CONCLUSION: The effects of Magliasa in TNBS-induced colitis are encouraging and warrant clinical trials for further confirmation.

Anti-inflammatory intestinal activity of Arctium lappa L. (Asteraceae) in TNBS colitis model

ETHNOPHARMACOLOGICAL RELEVANCE

In Brazilian traditional medicine, Arctium lappa (Asteraceae), has been reported to relieve gastrointestinal symptoms.

AIM OF THE STUDY

In the present study, we investigated the effects of the lactone sesquiterpene onopordopicrin enriched fraction (ONP fraction) from Arctium lappa in an experimental colitis model induced by 2,4,6 trinitrobenzene sulfonic acid and performed experiments to elucidate the underlying action mechanisms involved in that effect.

MATERIALS AND METHODS

ONP fraction (25 and 50 mg/kg/day) was orally administered 48, 24 and 1 h prior to the induction of colitis and 24 h after. The inflammatory response was assessed by gross appearance, myeloperoxidase (MPO) activity, tumor necrosis factor alpha (TNF-α) levels and a histological study of the lesions. We determined cyclooxygenase (COX)-1 and -2 protein expressions by western blotting and immunohistochemistry assays.

RESULTS

TNBS group was characterized by increased colonic wall thickness, edema, diffuse inflammatory cell infiltration, increased MPO activity and TNF-α levels. On the contrary, ONP fraction (25 and 50 mg/kg) treatment significantly reduced the macroscopic inflammation scores (p<0.05 and p<0.01, respectively) and morphological alterations associated with an increase in the mucus secretion. Similarly, the degree of neutrophil infiltration and the cytokine levels were significantly ameliorated. Moreover, COX-2 expression was up regulated in TNBS-treated rats. In contrast, ONP fraction (50 mg/kg) administration reduced COX-2 overexpression.

CONCLUSIONS

We have shown that the ONP fraction obtained from Arctium lappa exert marked protective effects in acute experimental colitis, confirming and justifying, at least in part, the popular use of this plant to treat gastrointestinal diseases.

Vedolizumab for the treatment of ulcerative colitis and Crohn's disease

Crohn's disease and ulcerative colitis are chronic, relapsing inflammatory disorders of the GI tract. In both Crohn's disease and ulcerative colitis, leukocytic infiltration of the mucosa is associated with epithelial damage. Recently, monoclonal antibodies directed against cell adhesion molecules (CAMs) involved in leukocyte extravasation have been developed. Natalizumab, the first drug brought to market targeting CAMs, is clinically effective but is associated with serious adverse effects including the uncommon, but often fatal, neurological disease progressive multifocal leukoencephalopathy. Vedolizumab targets a subset of the CAMs blocked by natalizumab and is currently in Phase III trials to study its efficacy and safety in patients with inflammatory bowel disease. Here, we discuss the current treatment options available for patients with Crohn's disease or ulcerative colitis, the history of CAM inhibitors, the current state of development of vedolizumab and its future role in inflammatory bowel disease, if approved by regulatory agencies.

Infliximab as a rescue treatment in difficult-to-treat autoimmune hepatitis

BACKGROUND & AIMS

Autoimmune hepatitis is a chronic inflammatory liver disease that leads to liver cirrhosis and corresponding complications, if left untreated. Current standard treatment with azathioprine and prednisolone induces remission in the vast majority of patients. However, for those patients not responding to standard treatment or not tolerating these drugs, few alternatives can be used and their effectiveness might be limited. We sought to analyze the safety and efficacy of off-label treatment with infliximab in a cohort of eleven patients with difficult-to-treat autoimmune hepatitis.

METHODS

Patients with difficult-to-treat autoimmune hepatitis who could not be brought into remission with standard treatment, either due to drug intolerance or to insufficient drug impact, were treated off-label with infliximab for a minimum of six months. Patient files were reviewed retrospectively.

RESULTS

Treatment with infliximab led to reduction of inflammation, evidenced by a decrease in transaminases (mean AST prior treatment 475 U/L ± 466, mean AST during treatment 43 U/L ± 32) as well as in immunoglobulins (pretreatment mean IgG 24.8 mg/dl ± 10.1, mean IgG during treatment 17.38 mg/dl ± 6). Infectious complications occurred in seven out of eleven patients and close monitoring was necessary.

CONCLUSIONS

Infliximab may be considered as rescue therapy in patients with difficult-to-treat autoimmune hepatitis, albeit treatment may be associated with infectious complications.

Efficacy of infliximab in acute severe ulcerative colitis: A single-centre experience

AIM: To suggest infliximab (IFX) is effective for acute severe ulcerative colitis, from real-life clinical practice.

METHODS: All patients receiving IFX for the treatment of acute severe ulcerative colitis in a single centre were included. Data were extracted from clinical records in order to assess response to IFX therapy. The primary endpoint was colectomy-free survival, and secondary outcomes included glucocorticosteroid-free remission and safety, which was evaluated by recording deaths and adverse events. Demographic and clinical characteristics of those who underwent colectomy and those who were colectomy-free, both at discharge from their index admission, and during follow-up after an initial response to IFX were compared.

RESULTS: Forty-four patients (16 females, mean age 36 years) received IFX between May 2006 and January 2012 for acute severe ulcerative colitis. The median duration of follow-up post-first infusion was 396 d (interquartile range = 173-828 d). There were 21 (47.7%) patients with < 1 year of follow-up, 10 (22.7%) with 1 years to 2 years of follow-up, and 13 (29.5%) with > 2 years of follow-up post-first infusion of IFX. Overall, 35 (79.5%) responded to IFX, avoiding colectomy during their index admission, 29 (65.9%) were colectomy-free at last point of follow-up (median follow-up 396 d), and 25 (56.8%) were in glucocorticosteroid-free remission at end of follow-up. There was one death from post-operative sepsis, 20 d after a single IFX infusion. Colectomy rates were generally lower among those “bridging” to thiopurine. Of 18 patients “bridged” to thiopurine therapy, 17 (94.4%) were colectomy-free, and 15 (83.3%) were in glucocorticosteroid-free remission at study end. No predictors of response were identified.

CONCLUSION: IFX is effective for acute severe ulcerative colitis in real-life clinical practice. Two-thirds of patients avoided colectomy, and more than 50% were in glucocorticosteroid-free remission.

Prevention of postoperative recurrence of Crohn's disease: Tripterygium wilfordii polyglycoside versus mesalazine

OBJECTIVES

To explore effectiveness and safety of polyglycosides of Tripterygium wilfordii (GTW) and mesalazine (5-aminosalicylic acid [5-ASA]) in preventing postoperative clinical and endoscopic recurrence of Crohn's disease.

METHODS

In this prospective, single-centre, single-blind study, postoperative Crohn's disease patients in remission were randomized to receive 1 mg/kg GTW daily, orally, or 4 g 5-ASA daily, orally, for 52 weeks. Patients underwent physical examinations, ileocolonoscopies and biochemical analyses at baseline and weeks 13, 26 and 52, or when clinical recurrence was suspected. Outcome measures were proportion of patients showing clinical or endoscopic recurrence at week 52, and changes in Rutgeerts' and Crohn's Disease Activity Index (CDAI) scores.

RESULTS

Twenty-one patients were assigned to receive GTW and 18 to 5-ASA; two patients on GTW and one on 5-ASA were withdrawn. Clinical and endoscopic recurrences were less common in the GTW group (n = 4) versus the 5-ASA group (n = 9). There were improvements in Rutgeerts' scores for those taking GTW. Mean between-group CDAI scores were similar. No serious adverse events were reported.

CONCLUSION

These findings indicate that GTW appears to be an effective, well-tolerated prophylactic regimen, superior to oral 5-ASA, for preventing clinical and endoscopic recurrence in postsurgical Crohn's disease.

Pediatric Ulcerative Colitis: The Therapeutic Road to Infliximab

Ulcerative colitis (UC) is a chronic inflammatory bowel disease that has significant morbidities in the pediatric population. Goals of medical therapy include induction and maintenance of remission while preserving the colon and it's function, while minimizing the risk of treatment related morbidities. For those children who do not respond to initial therapies and progress to develop moderately-to-severely active UC, there has been a dearth of available treatments to help induce remission, necessitating long-term corticosteroid usage, with associated comorbidities of chronic steroid treatment. Significant advances have been made in medical management, including the use of biologic therapies, specifically anti-tumor necrosis factor-α monoclonal antibodies. With the Food and Drug Administration's recent approval of the use of infliximab, a chimeric anti-tumor necrosis factor-α antibody, for children ≥6 years of age with moderately-to-severely active UC, care providers now have a new treatment regimen to offer this pediatric population.

Infected urachal cyst secondary to a Crohn's enterourachal fistula

Enterourachal fistulas are exceedingly rare in Crohn's patients. We report a case of a presumed enterourachal fistula that led to an infected urachal cyst. Preoperative medical treatment obliterated the fistula and avoided the need to resect bowel at the time of operation. We recommend consideration of this diagnosis in a Crohn's patient with a midline abdominal mass.

Natalizumab for moderate to severe Crohn's disease in clinical practice: the Mayo Clinic Rochester experience

BACKGROUND

Not all patients with Crohn's disease (CD) respond or maintain response to anti-tumor necrosis factor (TNF) agents and alternative treatment is necessary. Natalizumab, a monoclonal antibody to alpha-4 integrin approved for CD, has demonstrated efficacy in randomized clinical trials. We describe our experience with natalizumab in clinical practice at Mayo Clinic Rochester.

METHODS

Consecutive patients prescribed natalizumab for active CD were invited to participate and were followed prospectively. Incidence of infection, hospitalization, neoplasm, or other adverse events were recorded. Clinical activity was assessed using the Harvey-Bradshaw Index at each 30-day infusion visit.

RESULTS

Between April 2008 and September 2010, 36 patients were prescribed natalizumab and 30 (83.3%) agreed to participate. Median disease duration was 9 years (range, 3-43). Twenty-three patients had prior exposure to two anti-TNF agents, seven to one agent. All patients experienced at least one adverse event; none of the 13 patients in whom natalizumab was stopped (43%) discontinued due to adverse events. Five patients had infusions held for infection. No patient developed progressive multifocal leukoencephalopathy (PML). Fourteen patients (46%) had clinical response. The cumulative probability of achieving complete response within 1 year was 56% (28%-73%). Four of seven patients were weaned off corticosteroids.

CONCLUSIONS

In our experience with natalizumab in clinical practice, adverse events were manageable and did not result in treatment cessation. No PML cases were seen and clinical response was similar to that in clinical trials. Natalizumab results in clinical benefit in patients who have active disease and have failed anti-TNF therapy.

Anti-inflammatory procyanidins and triterpenes in 109 apple varieties

We evaluated the potential of apple to reduce inflammation. Phenolic compounds and triterpenes were analyzed in 109 apple cultivars. Total phenolics ranged from 29 to 7882 μg g(-1) of fresh weight (FW) in the flesh and from 733 to 4868 μg g(-1) FW in the skin, with flavanols including epicatechin and procyanidins as major components. Ursolic (44.7 to 3522 μg g(-1) FW) and oleanolic (47.2 to 838 μg g(-1) FW) acids dominated the skin triterpene profile. Five chemically contrasting cultivars were fractionated and their immune-modulating activity measured using two cell-based assays targeting key points in the inflammation process. Cultivars exhibiting high contents of procyanidins were the most potent at inhibiting NF-κB while triterpene-rich fractions reduced the promoter activity of the gene of TNFα. This study provides new insights into how apple genetic diversity could be used to alleviate inflammation.

Angioedema associated with Crohn's disease: Response to biologics

A 46-year-old female patient with terminal ileum Crohn’s disease and ankylosing spondylitis presented with recurrent angioedema and urticaria. Investigations ruled out hereditary angioedema, and environmental or food allergen triggers. She was diagnosed with chronic idiopathic urticaria with angioedema, and was treated with a trial of intravenous immunoglobulin immunotherapy, danazol, prednisone and hydroxyzine. Due to ongoing bowel and arthritic complaints, she was started on infliximab infusions and within 2 treatments, she had complete resolution of the angioedema and urticaria, as well as of the bowel and arthritic symptoms. Unfortunately she developed allergic reactions to the infliximab and was switched to another anti-tumor necrosis factor (TNF)-α agent, adalimumab. Since then, she has had no further angioedema or urticaria, and her Crohn’s disease has been quiescent. This is the first known case report of chronic idiopathic urticaria with angioedema coexistent with Crohn’s disease that was successfully treated with anti-TNF-α agents.

Patients enrolled in randomized controlled trials do not represent the inflammatory bowel disease patient population

BACKGROUND & AIMS

Multiple randomized controlled trials (RCTs) have been conducted to determine therapeutic efficacy of the biological agents for the inflammatory bowel diseases (IBD). However, the external validity of findings from RCTs might be compromised by their stringent selection criteria. We investigated the proportion of patients encountered during routine clinical practice who would qualify for enrollment into a pivotal RCT of biological agents for IBD.

METHODS

We performed a retrospective cohort study of adult patients with moderate-severe IBD who presented to a tertiary referral center. Inclusion and exclusion criteria were extracted from published RCTs of biologics approved by the Food and Drug Administration and applied to the study population.

RESULTS

Only 31.1% of 206 patients with IBD (34% with Crohn's disease [CD], 26% with ulcerative colitis) would have been eligible to participate in any of the selected RCTs. Patients would have been excluded because they had stricturing or penetrating CD, took high doses of steroids, had comorbidities or prior exposure to biologics, or received topical therapies. Of the trial-ineligible patients with ulcerative colitis, 23.3% had colectomies, and 31.7% received infliximab, with a 63.2% response rate. Approximately half (49.4%) of the 82 trial-ineligible patients with CD received biological therapies, with lower response rates (60%) than trial-eligible patients (89%; P = .03).

CONCLUSIONS

Most patients with moderate-severe IBD evaluated in an outpatient practice would not qualify for enrollment in a pivotal RCT of biological reagents; this finding raises important questions about their therapeutic efficacy beyond the clinical trial populations. Additional evaluation of the transparency of RCT design and selection criteria is needed to determine whether trial results can be generalized to the population.

Recent advances in the development of new treatments for celiac disease

INTRODUCTION

Celiac disease is a common autoimmune condition induced by dietary gluten in genetically susceptible individuals. So far, the only available treatment for the disorder is a lifelong strict gluten-free diet, because of which small intestinal histological changes recover and symptoms disappear. However, gluten-free dieting is restrictive, and nutritionally less than optimal, and gluten is difficult to avoid.

AREAS COVERED

With improving insight into the pathogenesis of celiac disease, several possible drug targets have been suggested. The new strategies include degradation of gluten intraluminally, reduction of mucosal permeability, inhibition of the transglutaminase 2 enzyme, blocking antigen presentation by HLA-DQ2 or HLA-DQ8, modulation of the immune responses of many cytokines, and vaccination.

EXPERT OPINION

Non-dietary treatment options are warranted either as adjunctive therapy together with dieting or to replace the gluten-free diet. The key question is whether the envisaged novel drug is able to prevent gluten-induced small intestinal mucosal injury as efficiently as a strict gluten-free diet, alleviating symptoms and signs of the disease. Furthermore, the gluten dose that can be detoxified, if at all, must be established. The new drug should also be as safe as dietary treatment. Several novel treatment options are under development.

[Guidelines for the management of ulcerative colitis]

Ulcerative colitis (UC) is a chronic inflammatory bowel disorder characterized by a relapsing and remitting course. The quality of life can decreases significantly during exacerbations of the disease. The incidence and prevalence of UC in Korea are still lower than those of Western countries, but have been rapidly increasing during the past decades. Various medical and surgical therapies are currently used for the management of UC. However, many challenging issues exist and sometimes these lead to differences in practice between clinicians. Therefore, Inflammatory Bowel Diseases (IBD) Study Group of Korean Association for the Study of Intestinal Diseases (KASID) set out the Korean guidelines for the management of UC. These guidelines are made by the adaptation using several foreign guidelines and encompass treatment of active colitis, maintenance of remission and indication for surgery in UC. The specific recommendations are presented with the quality of evidence. These are the first Korean treatment guidelines for UC and will be revised with new evidences on treatment of UC.

Surgical treatment of ulcerative colitis in the biologic therapy era

Recently introduced in the treatment algorithms and guidelines for the treatment of ulcerative colitis, biological therapy is an effective treatment option for patients with an acute severe flare not responsive to conventional treatments and for patients with steroid dependent disease. The reduction in hospitalization and surgical intervention for patients affected by ulcerative colitis after the introduction of biologic treatment remains to be proven. Furthermore, these agents seem to be associated with increase in cost of treatment and risk for serious postoperative complications. Restorative proctocolectomy with ileal pouch-anal anastomosis is the surgical treatment of choice in ulcerative colitis patients. Surgery is traditionally recommended as salvage therapy when medical management fails, and, despite advances in medical therapy, colectomy rates remain unchanged between 20% and 30%. To overcome the reported increase in postoperative complications in patients on biologic therapies, several surgical strategies have been developed to maintain long-term pouch failure rate around 10%, as previously reported. Surgical staging along with the development of minimally invasive surgery are among the most promising advances in this field.

MR enterography to evaluate sub-clinical intestinal inflammation in children with spondyloarthritis

BACKGROUND

Magnetic resonance enterography (MRE) is an established tool to evaluate for changes associated with inflammatory bowel disease (IBD), but has not been studied in sub-clinical IBD. We sought to evaluate the use of MRE in children with spondyloarthritis (SpA), who are at risk of having sub-clinical gut inflammation.

METHODS

Children with juvenile idiopathic arthritis (JIA) with evidence of intestinal inflammation as evidence by an abnormal fecal calprotectin assay were offered MRE of their intestines. Flavored sports drink containing polyethylene glycol 3350 was used as oral contrast. Glucagon was used to arrest peristalsis. Patients were imaged in the prone position on a 1.5 T scanner. Heavily T2-weighted fat-suppressed coronal and axial images using breath-hold technique were obtained, followed by post-gadolinium fat-suppressed T1-weighted gradient echo images.

RESULTS

We recruited five children with juvenile idiopathic arthritis (JIA); four had SpA, and one had poly-articular JIA. All five had evidence of intestinal inflammation based upon a positive fecal calprotectin assay and successfully completed the MRE. Three of the studies showed findings suggestive of IBD, including thickening and contrast uptake at the terminal ileum (TI) in one child, contrast uptake of the distal ileum in another, and prominent vasa recta and mesenteric lymph nodes in the third. The child with evidence of inflammatory changes at the TI underwent colonoscopy, which revealed inflammatory bowel disease limited to the TI.

CONCLUSIONS

MRE can be used to evaluate for subclinical IBD in children with JIA. This protocol was safe and well-tolerated, and identified mild changes in three of the subjects.

Medical management of Crohn's disease

INTRODUCTION

The medical approach to Crohn's disease has been modified in recent years thanks to the introduction of new therapies, like biologics. Also, well-designed studies and systematic reviews have allowed better evaluation of the role of old drugs like steroids and immunosuppressors. This review aims to evaluate the recent evidence on the medical approach to Crohn's disease in the different settings of the disease.

AREAS COVERED

Randomized controlled trials and meta-analyses were included in the review. The research on all the studies discussed was based on the Cochrane Library, Medline and Embase, using the following medical subject headings: Crohn's disease, clinical trial, therapy, 5-aminosalicylic acid, steroid, budesonide, immunosuppressant, anti-meta-analysis TNF and biologics.

EXPERT OPINION

In a mild active inflammatory ileocecal disease, budesonide is considered the best approach. The efficacy of aminosalicylates is limited, but a trial that has recently compared aminosalicylates and budesonide has shown that the two drugs are comparable. In a mild colonic disease, sulfasalazine, antibiotics and steroids are effective but the evidence for antibiotics is less clear. The maintenance of remission in this setting is debatable, but sulfasalazine seems the better choice. In a moderate severe ileal and colonic disease, steroids are the best therapy to induce remission. Once remission is reached, immunosuppressors remain today the better choice to maintain the remission. Anti-TNF therapy is indicated in patients intolerant or not responding to steroids and immunosuppressors and in fistulizing Crohn's disease. Early therapy with biologics may be considered in patients with severe disease.

Treatment of hospitalized adult patients with severe ulcerative colitis: Toronto consensus statements

OBJECTIVES

The objective of this study was to provide updated explicit and relevant consensus statements for clinicians to refer to when managing hospitalized adult patients with acute severe ulcerative colitis (UC).

METHODS

The Canadian Association of Gastroenterology consensus group of 23 voting participants developed a series of recommendation statements that addressed pertinent clinical questions. An iterative voting and feedback process was used to do this in conjunction with systematic literature reviews. These statements were brought to a formal consensus meeting held in Toronto, Ontario (March 2010), when each statement was discussed, reformulated, voted upon, and subsequently revised until group consensus (at least 80% agreement) was obtained. The modified GRADE (Grading of Recommendations Assessment, Development, and Evaluation) criteria were used to rate the strength of recommendations and the quality of evidence.

RESULTS

As a result of the iterative process, consensus was reached on 21 statements addressing four themes (General considerations and nutritional issues, Steroid use and predictors of steroid failure, Cyclosporine and infliximab, and Surgical issues).

CONCLUSIONS

Key recommendations for the treatment of hospitalized patients with severe UC include early escalation to second-line medical therapy with either infliximab or cyclosporine in individuals in whom parenteral steroids have failed after 72 h. These agents should be used in experienced centers where appropriate support is available. Sequential therapy with cyclosporine and infliximab is not recommended. Surgery is an option when first-line steroid therapy fails, and is indicated when second-line medical therapy fails and/or when complications arise during the hospitalization.

Enterocutaneous fistula as early presentation of Crohn's disease in an adult woman

Crohn's disease is a chronic transmural inflammatory process that primarily affects the gastrointestinal tract, with several extra-intestinal manifestations. Though patients usually present with vague abdominal pain, initial presentation can be at an advanced stage or with extra-intestinal pathology. The authors report the case of a 59-year-old woman, who presented with a tubo-ovarian abscess that resulted in a protracted non-healing enterocutaneous fistula, which was eventually diagnosed as Crohn's disease approximately 2 years after initial presentation. Relevant literature is reviewed, as well as time-points where an earlier diagnosis could have been made thereby underscoring the importance of considering Crohn's Disease in a non-healing enterocutaneous fistula in an otherwise asymptomatic patient.

Efficacy and tolerability of methotrexate therapy for refractory Crohn's disease: a large single-centre experience

BACKGROUND

Randomised controlled trials demonstrate that methotrexate is effective in inducing remission and preventing relapse of Crohn's disease (CD) as a first-line immunosuppressant, but efficacy data after failure with, or intolerance to, thiopurines are limited.

AIMS

To report efficacy of methotrexate in a cohort of refractory CD patients, most of whom had not responded to, or were intolerant of, thiopurines.

METHODS

Data were collected for patients receiving methotrexate for active CD. Response to methotrexate induction therapy at 4 months, and sustained clinical benefit at last point of follow-up with maintenance therapy, were assessed via physician's global assessment. Demographic and disease factors predicting response, or sustained clinical benefit, were examined by univariate and multivariate analysis.

RESULTS

Sixty-six [38 (54%) female patients, mean age at diagnosis 29.4 years] patients received methotrexate between 2001 and 2010, 61 (92%) of whom received the drug parenterally. Sixty patients had failed, or were intolerant of, thiopurines. Response to therapy at 4 months occurred in 54 (82%) patients. However, sustained clinical benefit occurred in only 19 (29%) patients at last point of follow-up, including six patients who discontinued the drug for family planning reasons. No predictors of response or sustained clinical benefit were identified. Adverse events occurred in 20 (30%) patients.

CONCLUSIONS

These data suggest that methotrexate is effective in terms of initial response in Crohn's disease patients who have failed, or are intolerant of, thiopurines. However, efficacy is not sustained in the long term.

Impact of smoking on disease phenotype and postoperative outcomes for Crohn's disease patients undergoing surgery

AIM

Whether smoking affects disease distribution, phenotype, and perioperative outcomes for Crohn's disease (CD) patients undergoing surgery is not well characterized. The aim of this study is to evaluate the impact of smoking on disease phenotype and postoperative outcomes for CD patients undergoing surgery

METHODS

Prospectively collected data of CD patients undergoing colorectal resection were evaluated. CD patients who were current smokers (CS) were compared to nonsmokers (NS) and ex-smokers (ES) for disease phenotype, anatomic site involved, procedures performed, postoperative outcomes, and quality of life using the Cleveland Global Quality of Life instrument (CGQL).

RESULTS

Of 691 patients with a diagnosis of CD requiring surgery 314 were classified as CS, 330 as NS, and 47 as ES. CS and ES in comparison to NS were significantly older at diagnosis of Crohn's disease (mean, 29.3 vs. 29.2 vs. 26.3 years) (P = 0.001) and older at the time of primary surgery (mean, 42.9 vs. 48.4 vs. 39 years) (P = 0.001) with a greater frequency of diabetes. In all groups requiring surgery, there was a significant change in disease phenotype from the time of diagnosis to surgical intervention. The predominant phenotype at diagnosis was inflammatory which changed to stricturing and penetrating as the dominant phenotypes at time of surgery. All groups had a significant improvement in CGQL scores post-surgery with the greatest benefit observed in NS. Postoperative complications and 30-day readmission rates were similar between all groups.

CONCLUSIONS

The findings of this study show that in patients with CD, disease phenotype changes over time. This occurs independent of smoking. Smoking does not appear to predispose to complications for CD patients undergoing surgery. CS and ES have a persistently reduced quality of life in comparison to NS post-surgery.

Emerging immunological targets in inflammatory bowel disease

Crohn's disease (CD) and ulcerative colitis (UC) are the major forms of inflammatory bowel diseases (IBD) in man. They are caused by damage to the lining of the intestine and deeper layers, due to an excessive immune response directed against components of the gut microflora and poorly controlled by counter-regulatory mechanisms. CD and UC are however immunologically distinct. CD-related inflammation is characterized by a marked mucosal infiltration of T lymphocytes secreting T helper type (Th) 1 and Th17 cytokines. In UC, the local immune response is less polarized but may show enhanced production of IL-5, IL-13 and Th17 cytokines. Downstream however CD and UC share important end-stage effector pathways of intestinal injury, mediated by an active cross-talk between immune and non-immune cells. The clarification of the complex networks of immune-inflammatory mediators operating in the gut of IBD patients has led to the identification of new targets that should facilitate the development of novel biological therapies.

Optimal use and cost-effectiveness of biologic therapies in inflammatory bowel disease

Inflammatory bowel diseases (IBD), namely Crohn's disease and ulcerative colitis, are burdened by high medical costs which are mostly dependent on hospital inpatient treatment. New biologic therapies, which target specific cytokines in the inflammatory cascade leading to the intestinal lesions, including tumor necrosis factor (TNF)-α, have revolutionized the management of IBD by offering a therapeutic chance to patients in whom conventional therapies failed. However, the relatively high costs of biologic drugs, together with their potential toxicity due to infections and malignancies, have led to debate regarding their indiscriminate use in IBD patients. The purpose of this review is to deal with the optimal use and cost-effectiveness of the two main monoclonal anti-TNF-α agents currently used in the management of IBD patients, i.e. the chimeric human/murine antibody infliximab and the fully human antibody adalimumab.

Infliximab to treat Crohn's disease: an update

Crohn’s disease (CD) is a chronic inflammatory disease of the gastrointestinal tract characterized by recurring flares followed by periods of inactive disease and remission. The etiology is unknown, although the common opinion is that the disease arises from a disordered immune response to the gut contents in genetically predisposed individuals. Infliximab (IFX), a chimeric immunoglobulin G1 monoclonal antibody to tumor necrosis factor, has dramatically changed the approach to managing patients with CD and improving their treatment, by achieving treatment goals, such as mucosal healing, and decreasing the need for hospitalizations and surgeries. This review provides an update on existing evidence for the use of IFX in CD, taking into account the safety profile in clinical practice and special situations such as pregnancy. Antitumor necrosis factor therapy has been evaluated as an induction and maintenance therapy in CD in several randomized controlled trials and meta-analyses, showing efficacy in both clinical settings. Early use of biologics may improve patient outcomes in active CD. However, a widespread use of a “top-down” approach in all CD patients cannot be recommended. Clinical factors at diagnosis may predict poor outcome in CD, and should be taken into account when determining the initial therapeutic approach.