Ustekinumab for the treatment of Crohn's disease: can it find its niche?

Early fecal calprotectin levels at week 8 may guide therapeutic decisions on Ustekinumab therapy in patients with Crohn's disease

BACKGROUND

Response evaluation after induction therapy with ustekinumab (UST) in Crohn's disease (CD) is important for decisions on maintenance therapy. We aimed to assess the potential of fecal calprotectin (FC) levels to predict endoscopic response at week 16.

METHODS

CD patients with FC >100 µg/g and endoscopic active disease (SES-CD> 2, Rutgeerts' score ≥ i2) at initiation of UST therapy were enrolled. FC was determined at weeks 0, 2, 4, 8 and 16 and patients underwent a colonoscopy at week 16. The primary outcome was an endoscopic response at week 16 (SES-CD score ≥50% decrease or a decrease of ≥1 points in Rutgeerts' score). The optimal cut-off levels of FC and change in FC to predict endoscopic response were determined using ROC statistics.

RESULTS

59 CD patients were included. Endoscopic response was observed in 21/59 (36%) patients. The diagnostic accuracy for FC levels at week 8 to predict endoscopic response at week 16 showed a predictive value of 0.71. A decrease in FC levels ≥500 µg/g between baseline at week 8 indicates endoscopic response (PPV = 89%), whereas absence of any decrease indicates endoscopic non-response after induction (NPV = 81%).

CONCLUSIONS

Continuation of UST therapy without endoscopic response evaluation may be considered in patients with a decrease in FC levels of ≥500 µg/g at week 8. The decision on continuation of UST therapy or therapy optimization needs reconsideration in patients without a decrease of FC level. In all other patients, endoscopic response evaluation of induction therapy remains essential for therapeutic decisions.

Polyphenols and inflammatory bowel disease: Natural products with therapeutic effects?

Inflammatory bowel disease (IBD) is a long-life disease with periods of recurrence and relief. Oxidative stress plays an important role in the pathogenesis of this disease. Recent years' studies in the field of IBD treatment mostly have focused on targeting cytokines and immune cell trafficking using antibodies and inhibitors, altering the composition of intestinal bacteria in the line of attenuation of inflammation using probiotics and prebiotics, and attenuating oxidative stress through antioxidant supplementation. Studies in animal models of IBD have shown that some polyphenolic compounds including curcumin, quercetin, resveratrol, naringenin, and epigallocatechin-3-gallate can affect almost all of the above aspects and are useful compounds in the treatment of IBD. Clinical studies performed on IBD patients have also confirmed the findings of animal model studies and have shown that supplementation with some of the above-mentioned polyphenolic compounds has positive effects in reducing disease clinical and endoscopic activity, inducing and maintaining remission, and improving quality of life. In this review article, in addition to a detailed reviewing the effects of the above-mentioned polyphenolic compounds on the events involved in the pathogenesis of IBD, the results of these clinical studies will also be reviewed.

Safety and Efficacy of Ustekinumab in the Treatment of Crohn Disease: A Systematic Review and Meta-analysis

Background and Aims The present systematic review and meta-analysis was designed to estimate the safety and effectiveness of ustekinumab in the treatment of Crohn disease (CD) in clinical trials and observational studies.

Methods We retrieved all the related publications from the PubMed, Cochrane, EBSCO, Google Scholar and EMBASE databases using a systematic search strategy. We only included clinical trials and observational studies that were published in English.

Results Only 31 studies that met the eligibility criteria out of the 733 identified studies were included. The overall clinical response rate in the cohort studies was of 0.539 (95% confidence interval [95%CI]: 0.419–0.659), and in the clinical trials it was of 0.428 (95%CI: 0.356–0.501). The pooled clinical remission rate was of 0.399 (95%CI: 0.295–0.503) in randomized control trials (RCTs,) and of 0.440 (95%CI: 0.339–0.542) in cohort studies. The rate of adverse effects was of 0.158 (95%CI: 0.109–0.207) in cohort studies and of 0.690 (95%CI: 0.633–0.748) in RCTs.

Conclusion Ustekinumab is effective in the treatment of CD. However, more research is required on the safety profiles because there was considerable variation among the included studies.

Dual Biologic Therapy in an Adolescent With Camurati-Engelmann Disease and Crohn Disease

Camurati-Engelmann disease (CED) is a rare disorder caused by activating mutations in the TGF-β1 gene and characterized by hyperostosis of long bones and bone dysplasia. We describe a case of an adolescent with CED and moderate-severe Crohn Disease (CD). Infliximab improved gastrointestinal symptoms but was associated with worsening CED-associated bone pain. Clinical remission was successfully achieved with dual biologic therapy that included vedolizumab and ustekinumab. Possible reasons for this patient's clinical response are advanced and include speculation about the complex role of TGF-β1 signaling in the etiology of both CED and CD.

From single-target to cellular niche targeting in Crohn's disease: intercepting bad communications

The mainstay of moderate to severe Crohn's disease (CD), anti-TNF treatment, shows no clinical benefit in ∼40% of patients, likely due to incomplete cellular targeting and delayed treatment institution. While single-target therapeutics have been highly effective for some CD patients, substantial limitations with respect to safety, efficacy, and long-term, complete remission remain. Deconvolution of the cellular and molecular circuitry of tissue lesions underscores the importance of combinatorial strategies targeting cellular niches. This review aims to evaluate current therapeutic approaches used to manage CD, and highlight recent advances to our cellular, genetic, and molecular understanding of mechanisms driving pathogenic niche activation in CD. We propose new frameworks outlining that combinatorial therapies, along with serial tissue sampling and studies guided by genetics and genomics, can advance on current treatment approaches and will inform newer strategies upon which we can move towards precision therapeutics in IBD.

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

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

Ustekinumab in Crohn's disease: Real-world outcomes from the Sicilian network for inflammatory bowel diseases

Background and Aim

Ustekinumab is approved in Europe for the treatment of moderate to severe Crohn's disease (CD). Italian real‐life data are scarce, so the aim of this study was to assess the effectiveness and safety of ustekinumab in an Italian cohort of CD patients.

Methods

Data of patients with CD who started using ustekinumab were extracted from the cohort of the Sicilian Network for Inflammatory Bowel Disease. Primary end‐points were steroid‐free clinical remission at 8, 24, and 52 weeks of therapy and reduction of C‐reactive protein. Secondary end‐points were treatment response, treatment persistence at 12 months, and safety.

Results

A total of 131 patients (males 56%; mean age 46 years ±15) were included. All patients were biologics experienced except for one. At 24 and 52 weeks, 40% and 43% of patients achieved steroid‐free clinical remission, and 64% and 62% had clinical response, respectively. At the end of follow‐up, there was a significant reduction of steroid use (P = 0.012) and of the Harvey‐Bradshaw Index (P = 0.001). The probability of persistence in therapy with ustekinumab after 12 months of treatment was 89%. The only factor associated with discontinuation was older age.

Conclusions

Data from our real‐life cohort of treatment‐refractory CD patients suggest the satisfactory effectiveness and safety profile of ustekinumab.

Short and Long-Term Effectiveness of Ustekinumab in Patients with Crohn's Disease: Real-World Data from a German IBD Cohort

Background and Aims: The IL-12/23 inhibitor ustekinumab (UST) opened up new treatment options for patients with Crohn’s disease (CD). Due to the recent approval, real-world German data on long-term efficacy and safety are lacking. This study aimed to assess the clinical course of CD patients under UST therapy and to identify potential predictive markers. Methods: Patients with CD receiving UST treatment in three hospitals and two outpatient centers were included and retrospectively analyzed. Rates for short- and long-term remission and response were analyzed with the help of clinical (Harvey–Bradshaw Index (HBI)) and biochemical (C-reactive protein (CRP), Fecal calprotectin (fCal)) parameters for disease activity. Results: Data from 180 patients were evaluated. One-hundred-and-six patients had a follow-up of at least eight weeks and were included. 96.2% of the patients were pre-exposed to anti- TNFα agents and 34.4% to both anti-TNFα and anti-integrin antibodies. The median follow-up was 49.1 weeks (95% CI 42.03-56.25). At week 8, 51 patients (54.8%) showed response to UST, and 24 (24.7%) were in remission. At week 48, 48 (51.6%) responded to UST, and 25 patients (26.9%) were in remission. Steroid-free response and remission at week eight was achieved by 30.1% and 19.3% of patients, respectively. At week 48, 37.6% showed steroid-free response to UST, and 20.4% of the initial patient population was in steroid-free remission. Conclusion: Our study confirms short- and long-term UST effectiveness and tolerability in a cohort of multi-treatment-exposed patients.

Long-term Clinical Effectiveness of Ustekinumab in Patients with Crohn's Disease Who Failed Biologic Therapies: A National Cohort Study

BACKGROUND

Ustekinumab [UST] was recently approved in Europe for the treatment of moderate to severe Crohn's disease [CD]. Long-term real-world data are currently scarce for CD patients previously exposed to several biologics.

METHODS

This is an observational, national, retrospective multicentre study. Patients received intravenous UST ~6 mg/kg at baseline, with 90 mg subcutaneously thereafter every 8 weeks. Response and remission rates were assessed at Weeks 8, 16, and 52.

RESULTS

Data from 152 patients were analysed. All patients were exposed to at least one anti-TNFα agent, with 69.7% were exposed to even two anti-TNFα and vedolizumab. After 1 year, 42.1% and 25.7% of patients had experienced clinical response and clinical remission, respectively, and 38.8% and 24.3% had achieved steroid-free clinical response and remission, respectively; 38.8% of patients discontinued therapy during the 12 months of follow-up. Colonic location was predictive of clinical response at 1 year, and low body mass index [BMI] at baseline was a negative predictor of clinical remission. Resolution of arthralgia was associated with clinical response over time. De novo arthralgia was reported by 17.9% of patients at Week 8 and 13.5% of patients at Week 52. No impact of UST on arthralgia was observed in patients with concomitant ankylosing spondylitis [n = 17]. Others adverse events were reported in 7.2% of patients.

CONCLUSIONS

This real-world cohort study confirms the effectiveness of UST in CD patients previously exposed to several biologics. Ustekinumab was well tolerated with respect to adverse events.

PODCAST

This article has an associated podcast which can be accessed at https://academic.oup.com/ecco-jcc/pages/podcast.

Impact of Genes and the Environment on the Pathogenesis and Disease Course of Inflammatory Bowel Disease

Crohn's disease and ulcerative colitis constitute two major subgroups of inflammatory bowel diseases (IBD), a group of complex polygenic diseases characterized by chronic and progressive inflammation in the gastrointestinal tract. In recent years, methodological advances in genetic analysis have greatly expanded our understanding of the genetic background of IBD. So far, more than 240 genetic risk loci have been identified for IBD. However, these risk alleles explain less than 30% of the susceptibility to disease development, suggesting that environmental factors contribute considerably. The increasing occurrence of IBD in Eastern countries following their 'westernization', as well as the increased risk of disease among those who migrate to high-incidence regions, also suggest that the environment is key in the pathogenesis of IBD. In this review, we summarize the current evidence on the role of genetic and environmental factors in the susceptibility to, and disease course of, IBD, and we suggest how these findings might be applied to clinical practice.

Ustekinumab is effective in biological refractory Crohn's disease patients-regardless of approval study selection criteria

BACKGROUND/AIMS

Ustekinumab is effective in active Crohn's disease. In a retrospective study we assessed the clinical outcome in nonresponders to anti-tumor necrosis factor therapy, and/or conventional therapy and/or the α4β7-integrin inhibitor vedolizumab. As approval study populations do not always reflect the average "real world" patient cohort, we assessed weather patients who would not have qualified for approval studies show similar outcomes.

METHODS

Forty-one patients with mild to severe active Crohn's disease were treated with ustekinumab (intravenous 6 mg per kg/body weight) followed by subcutaneous ustekinumab (90 mg) at week 8. Depending on the clinical response maintenance therapy was chosen every 8 or 12 weeks. Clinical response was defined by Crohn's Disease Activity Index (CDAI) decline, decline of stool frequency or clinical improvement. Inclusion criteria for approval studies were assessed.

RESULTS

The 58.5% (24/41) showed clinical response to ustekinumab. The 58.3% of this group (14/24) achieved clinical remission. Clinical response correlated significantly with drop of stool frequency and improvement of CDAI score. The 39 out of 41 patients had no side effects and we observed no serious infections. About a third of our patients would not have met ustekinumab approval study criteria. However, patients who did not meet study criteria showed clinical improvement numerically in the same range compared to patients who would have qualified for approval studies.

CONCLUSIONS

Ustekinumab is effective, safe and well tolerated in a highly therapy refractory patient cohort. Even though a reasonable number of patients did not meet ustekinumab approval study criteria, approval study results seem to be representative to the overall patient cohort.

The Expanding Role of Anti-IL-12 and/or Anti-IL-23 Antibodies in the Treatment of Inflammatory Bowel Disease

The interleukin (IL)-12/IL-23 pathway is one of many proposed mechanistic pathways of intestinal inflammation. Earlier studies introduced IL-12 as a major cytokine in the pathogenesis of inflammatory bowel disease. However, the discovery of IL-23 drew attention toward this new cytokine. Overwhelming data indicated that antibodies against IL-12p40 rendered their anti-inflammatory effect primarily via inhibition of IL-23. This is because IL-12 and IL-23 have the subunit p40 in common. These cytokines have become an attractive target of treatment in patients with inflammatory bowel disease. Targeting IL-12 selectively was not found to be an efficacious treatment. Coblockade of IL-12 and IL-23 via targeting of p40, however, was found to be effective. More recently, selective IL-23 blockade has been extensively studied with promising preliminary results. To date, there are several ongoing randomized clinical trials investigating the safety and efficacy profiles of selective IL-23 inhibitors. Overall, the classes of anti-IL-12/IL-23 inhibitors and selective IL-23 inhibitors seem to be effective alternatives in patients who are nonresponders to anti-tumor necrosis factor-α agents, especially in a subgroup of secondary nonresponders. In addition, the immunogenicity and adverse event rates associated with antibodies against IL-12 and/or IL-23 seem to be very low. Considering all of this, these agents will be an important part of the treatment algorithm for patients with inflammatory bowel disease going forward.

ILC3 function as a double-edged sword in inflammatory bowel diseases

Inflammatory bowel diseases (IBD), composed mainly of Crohn's disease (CD) and ulcerative colitis (UC), are strongly implicated in the development of intestinal inflammation lesions. Its exact etiology and pathogenesis are still undetermined. Recently accumulating evidence supports that group 3 innate lymphoid cells (ILC3) are responsible for gastrointestinal mucosal homeostasis through moderate generation of IL-22, IL-17, and GM-CSF in the physiological state. ILC3 contribute to the progression and aggravation of IBD while both IL-22 and IL-17, along with IFN-γ, are overexpressed by the dysregulation of NCR- ILC3 or NCR+ ILC3 function and the bias of NCR+ ILC3 towards ILC1 as well as regulatory ILC dysfunction in the pathological state. Herein, we feature the group 3 innate lymphoid cells' development, biological function, maintenance of gut homeostasis, mediation of IBD occurrence, and potential application to IBD therapy.

Traditional Chinese medicine for management of recurrent and refractory Crohn disease: A case report

INTRODUCTION

Crohn disease (CD) is a chronic relapsing systemic inflammatory disease afflicting the gastrointestinal system with a high morbidity. There has been increasing clinical interest in traditional Chinese medicine (TCM) treatment for CD. This report aims to present patient outcome of therapeutic management using TCM in combination with pharmacologic therapy.

PATIENT CONCERNS

A 53-year-old woman with a more than 23-year history of chronic indigestion, reflux, abdominal pain, and excessive diarrhea, and a more than 21-year history of recurrent refractory CD. The condition had been managed for 21 years with ongoing pharmacologic therapy, and surgical intervention; however, with poor therapeutic effect.

DIAGNOSIS

In this study, the diagnosis of CD was based on integrating patient symptoms and radiologic findings and biopsy results. The patient had no differential diagnosis.

INTERVENTIONS

The patient received acupuncture treatment at an approximate frequency of once per week for a total of 21 sessions until November 5, 2018. The patient also received Chinese herbal medicine (CHM) on an as-needed basis to manage her symptoms.

OUTCOMES

Patient reported symptoms of chronic indigestion, reflux, abdominal pain, and excessive diarrhea were substantially improved by combined TCM and pharmacologic therapy intervention, while the dosage of her medication was reduced.

CONCLUSION

Following acupuncture treatment, improvements of subjective symptoms: chronic indigestion, reflux, abdominal pain, and excessive diarrhea, were observed. CHM provided immediate relief of indigestion, reflux, and abdominal pain. TCM may be a potential therapeutic strategy to manage clinical symptoms of CD, if this is proven useful in future RCT studies.

Autophagy: A new concept in autoimmunity regulation and a novel therapeutic option

Nowadays, pharmacologic treatments of autoinflammatory diseases are largely palliative rather than curative. Most of them result in non-specific immunosuppression, which can be associated with broad disruption of natural and induced immunity with significant and sometimes serious unwanted injuries. Among the novel strategies that are under development, tools that modulate the immune system to restore normal tolerance mechanisms are central. In these approaches, peptide therapeutics constitute a class of agents that display many physicochemical advantages. Within this class of potent drugs, the phosphopeptide P140 is very promising for treating patients with lupus, and likely also patients with other chronic inflammatory diseases. We discovered that P140 targets autophagy, a finely orchestrated catabolic process, involved in the regulation of inflammation and in the biology of immune cells. In vitro, P140 acts directly on a particular form of autophagy called chaperone-mediated autophagy, which seems to be hyperactivated in certain subsets of lymphocytes in lupus and in other autoinflammatory settings. In lupus, the "correcting" effect of P140 on autophagy results in a weaker signaling of autoreactive T cells, leading to a significant improvement of pathophysiological status of treated mice. These findings also demonstrated ex vivo in human cells, open novel avenues of therapeutic intervention in pathological conditions, in which specific and not general targeting is highly pursued in the context of the new action plans for personalized medicines.

Ustekinumab in the management of Crohn's disease: Expert opinion

This expert-opinion paper reviews available evidence for the use of ustekinumab, a human interleukin 12/23 monoclonal antibody, in the treatment of Crohn's disease and discusses its potential role in the current treatment scenario for the condition. Ustekinumab appears to be associated with rapid and sustained clinical effect, as reported from the clinical research program, with additional support for potential mucosal healing. These characteristics are paralleled by a favorable safety profile, lack of immunogenicity and the presence of systemic anti-inflammatory activity. Importantly, ustekinumab requires only one single intravenous administration, while subsequent dosing is administered subcutaneously, with potential advantages for home-based therapy. Lastly, the dosage of ustekinumab is flexible. On the basis of the evidence, ustekinumab has a role in patients with primary failure or secondary loss of response to anti-tumor necrosis factor agents, as well as in those who have adverse events on front-line biologics or are reinitiating therapy after a treatment holiday. Current evidence suggests that ustekinumab may be particularly suitable in patients who present extra-intestinal manifestations of the disease or are at risk of infections. Ustekinumab may also be considered in the first-line setting, especially in frail patients, in young subjects or in those who have concomitant immune-mediated diseases.

Emerging Mechanisms of Innate Immunity and Their Translational Potential in Inflammatory Bowel Disease

Activation of the innate immune system through pattern-recognition receptor (PRR) signaling plays a pivotal role in the early induction of host defense following exposure to pathogens. Loss of intestinal innate immune regulation leading aberrant immune responses has been implicated in the pathogenesis of inflammatory bowel disease (IBD). The precise role of PRRs in gut inflammation is not well understood, but considering their role as bacterial sensors and their genetic association with IBD, they likely contribute to dysregulated immune responses to the commensal microbiota. The purpose of this review is to evaluate the emerging functions of PRRs including their functional cross-talk, how they respond to mitochondrial damage, induce mitophagy or autophagy, and influence adaptive immune responses by interacting with the antigen presentation machinery. The review also summarizes some of the recent attempts to harness these pathways for therapeutic approaches in intestinal inflammation.

Future Prospects of Biologic Therapies for Immunologic Diseases

This article presents an overview of future uses for biologic therapies in the treatment of immunologic and allergic conditions. Discussion is centered on the use of existing therapies outside of their current indication or on new therapies that are close to approval. This information may help familiarize practicing allergists and immunologists with therapies they may soon encounter in their practice as well as help identify conditions and treatments that will require further study in the near future.

Ustekinumab to treat Crohn's disease

Ustekinumab is a monoclonal antibody directed against the p40 subunit, which is part of interleukins IL-12 and IL-23. The efficacy of ustekinumab versus placebo in terms of clinical response and remission of induction has been shown in phase3 clinical trials. When used as subcutaneous maintenance therapy, the therapeutic benefit of ustekinumab over placebo has been confirmed in both clinical response and remission in patients who have responded clinically to induction therapy. In addition, ustekinumab has demonstrated an improvement in mucosal healing parameters. The safety profile of the drug has been good, with low infection rates (without reactivation of tuberculosis) and absence of tumour reporting. The development of drug immunogenicity appears to be rare. In summary, ustekinumab is a promising treatment option in patients with Crohn's disease, as an alternative to anti-TNFα drugs.

Host-Microbiota Interactions Shape Local and Systemic Inflammatory Diseases

Recent advances in understanding how the mammalian immune system and intestinal microbiota functionally interact have yielded novel insights for human health and disease. Modern technologies to quantitatively measure specific members and functional characteristics of the microbiota in the gastrointestinal tract, along with fundamental and emerging concepts in the field of immunology, have revealed numerous ways in which host-microbiota interactions proceed beneficially, neutrally, or detrimentally for mammalian hosts. It is clear that the gut microbiota has a strong influence on the shape and quality of the immune system; correspondingly, the immune system guides the composition and localization of the microbiota. In the following review, we examine the evidence that these interactions encompass homeostasis and inflammation in the intestine and, in certain cases, extraintestinal tissues. Lastly, we discuss translational therapies stemming from research on host-microbiota interactions that could be used for the treatment of chronic inflammatory diseases.

Ustekinumab: A Review in Moderate to Severe Crohn's Disease

Ustekinumab (Stelara^®) has been recently approved in the EU and the USA as intravenous induction and subcutaneous maintenance therapy for adult patients with moderately to severely active Crohn's disease who have failed or were intolerant to treatment with immunomodulators, corticosteroids or at least one tumour necrosis factor (TNF) antagonist. Ustekinumab, a monoclonal antibody to the shared p40 subunit of the proinflammatory interleukin (IL)-12 and IL-23 cytokines, has a unique mechanism of action distinct from that of TNF antagonists. In pivotal phase III trials, compared with placebo, ustekinumab induction therapy improved clinical response and remission rates in patients who had previously failed or were intolerant to conventional therapies or at least one TNF antagonist. When administered as subcutaneous maintenance therapy, ustekinumab continued to offer benefits over placebo for clinical response and remission in patients who had clinically responded to the induction therapy. Ustekinumab was generally well tolerated as both induction and maintenance therapy; serious infections and malignancies were rare. Thus, ustekinumab presents a promising alternative treatment option in patients with moderately to severely active Crohn's disease who have failed or are intolerant to treatment with conventional therapies or TNF antagonists.

Clinical, endoscopic and radiographic outcomes with ustekinumab in medically-refractory Crohn's disease: real world experience from a multicentre cohort

BACKGROUND

Ustekinumab is a monoclonal antibody targeting interleukins-12 and -23, with efficacy in Crohn's disease (CD) demonstrated in clinical trials.

AIM

To assess the real-world clinical, endoscopic and radiographic response and remission outcomes achieved with ustekinumab in medically-refractory CD.

METHODS

A retrospective multicentre cohort study was performed on CD patients receiving ustekinumab between 2011 and 2016. The primary outcome was achievement of clinical and objective steroid-free response and remission at 3, 6 and 12 months. Clinical response and remission were defined by reduction in Harvey Bradshaw Index (HBI) of ≥3 points and an HBI ≤4 points respectively. Objective response was defined by improvement in endoscopic or radiographic CD, as assessed by ileocolonoscopy, contrast-enhanced ultrasound or CT/MR enterography. Objective remission was defined by endoscopic mucosal healing or complete resolution of inflammatory parameters on radiographic assessment.

RESULTS

A total of 167 CD patients were treated with ustekinumab. 95.2% (159/167) previously failed anti-TNF therapy. Median follow-up was 45.6 weeks (IQR: 24.4-88.9). At 3 months, clinical response was achieved in 38.9% (65/167) and remission in 15.0% (25/167) of patients. At 6 months, clinical response was achieved in 60.3% (91/151) and remission in 25.2% (38/151) of patients. At 12 months, clinical response was achieved in 59.5% (66/111) and remission in 27.9% (31/111) of patients. Endoscopic or radiographic response was demonstrated in 54.5% (67/123) at 6 months and 55.8% (48/86) of patients at 12 months.

CONCLUSIONS

Ustekinumab is an effective therapeutic option for inducing and maintaining clinical, endoscopic and radiographic response in patients with Crohn's disease failing anti-TNF therapy.

Cells of the innate and adaptive immunity and their interactions in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a group of chronic inflammatory conditions of the gastrointestinal tract that includes two major phenotypes, Crohn's disease and ulcerative colitis that are characterized by different clinical features and different course of the immune response. The exact aetiology of IBD still remains unknown, although it is thought that the diseases result from an excessive immune response directed against microbial or environmentally derived antigens which can be triggered by the disruption of the intestinal epithelial barrier integrity. In this review we present immune mechanisms and interactions between cells of the immune system and tissue environment that contribute to the development and progression of IBD in humans. Since dysregulation of the intestinal immune response is a hallmark of chronic inflammatory conditions, we characterize cells of the innate and adaptive immunity involved in the pathogenesis of IBD and their cross-talks. We describe various subclasses of recently discovered innate lymphoid cells, as well as dendritic cells, macrophages and T cells, including Th17, Th22 and T regulatory cells, present in the intestinal lamina propria and cytokine-mediated regulation of the immune response in IBD, highlighting the role of IL-22 and IL-17A/IL-23 axis. Insights into novel therapeutic modalities targeting certain elements of the immune pathways important for the pathogenesis of IBD have been also shortly presented.

Top-down approach to biological therapy of Crohn's disease

INTRODUCTION

Crohn's disease (CD) is a chronic, immune-mediated condition with a potentially disabling and destructive course. Despite growing data on when to use a therapeutic 'top-down' strategy, clinical management of this complex disorder is still challenging. Currently, the discussion of 'top-down' strategy in CD mostly includes biological therapy alone or in combination. Areas covered: This article is based on a review of existing literature regarding the use of biological therapy in a 'top-down' approach for the treatment of Crohn's disease. The authors reviewed all the major databases including MEDLINE as well as DDW and ECCO abstracts, respectively. Expert opinion: A 'top-down' therapeutic approach in Crohn's disease is strongly supported by existing data in patients with several risk factors for a severe course of disease. Moreover, there is an increasing amount of published data recommending a more individualised therapeutic strategy to identify candidates for 'top-down' treatment, based on enhanced diagnostics using biomarkers. Emerging therapeutic approaches besides existing therapy concepts using biologicals may possibly redefine the 'top-down' therapeutic strategy for Crohn's disease in the future.

Chronic systemic inflammation originating from epithelial tissues

Chronic systemic inflammation (CSI) has recently been identified as a major contributor to common diseases ranging from cancer to metabolic disorders and neurologic alterations. In the last decade, we and others have generated genetically engineered mouse models for inflammatory diseases, which enable studying the molecular mechanisms of CSI. Recently, organ cross-talk induced by CSI under homeostatic and pathological conditions has begun to be appreciated. In this review, we will revisit whole organism physiology in relation to CSI originating from epithelial tissues, such as the skin and gut. Furthermore, we will discuss the current knowledge regarding the mechanisms, the specific immune cells and molecules responsible for inducing the most common comorbidities, such as cardiovascular, metabolic, and neurological complications, as well as bone loss, in heterogeneous diseases like psoriasis, atopic dermatitis, and inflammatory bowel disease. As it would be impossible to discuss all comorbidities of these diseases as well as all epithelial tissues, we present an overview with a special emphasis on our recent findings linking skin inflammation to bone loss.

Biological therapy targeting the IL-23/IL-17 axis in inflammatory bowel disease

INTRODUCTION

As many inflammatory bowel disease (IBD) patients do not benefit from long-term anti-tumour necrosis factor treatment, new anti-inflammatories are urgently needed. After the discovery of the interleukin (IL) 23/17 axis being pivotal in IBD pathogenesis, many different compounds were developed, targeting different components within this pathway. Areas covered: A literature search to March 2016 was performed to identify the most relevant reports on the role of the IL-23/IL-17 axis in IBD and on the different molecules targeting this pathway. First, the authors briefly summarize the immunology of the IL-23/IL-17 pathway to elucidate the mode of action of all different agents. Second, they describe all different molecules targeting this pathway. Besides discussing efficacy and safety data, they also explore immunogenicity, exposure during pregnancy and pharmacokinetics. Expert opinion: A new era in IBD treatment has recently been initiated: besides immunomodulators and TNF-antagonists, anti-adhesion molecules and monoclonal antibodies targeting the IL-23/IL-17 pathway have been developed. Biomarkers for personalized medicine are urgently needed. This therapeutic (r)evolution will further improve disease-related and patient-reported outcome, though a lot of questions should still be addressed in future years.

Management of complex perianal Crohn's disease

Patients with Crohn's disease often develop perianal disease, successfully managed in most cases. However, its most aggressive form, complex perianal disease, is associated with high morbidity and a significant impairment in patients' quality of life. The aim of this review is to provide an updated approach to this condition, reviewing aspects of its epidemiology, diagnosis and therapeutic alternatives. Emerging treatment options are also discussed. A multidisciplinary assessment of these patients with a coordinated medical and surgical approach is crucial.

Psoriasis and inflammatory bowel disease: links and risks

Psoriasis and the spectrum of inflammatory bowel diseases (IBD) are chronic, inflammatory, organotropic conditions. The epidemiologic coexistence of these diseases is corroborated by findings at the level of disease, biogeography, and intrafamilial and intrapatient coincidence. The identification of shared susceptibility loci and DNA polymorphisms has confirmed this correlation at a genetic level. The pathogenesis of both diseases implicates the innate and adaptive segments of the immune system. Increased permeability of the epidermal barrier in skin and intestine underlies the augmented interaction of allergens and pathogens with inflammatory receptors of immune cells. The immune response between psoriasis and IBD is similar and comprises phagocytic, dendritic, and natural killer cell, along with a milieu of cytokines and antimicrobial peptides that stimulate T-cells. The interplay between dendritic cells and Th17 cells appears to be the core dysregulated immune pathway in all these conditions. The distinct similarities in the pathogenesis are also reflected in the wide overlapping of their therapeutic approaches. Small-molecule pharmacologic immunomodulators have been applied, and more recently, biologic treatments that target proinflammatory interleukins have been introduced or are currently being evaluated. However, the fact that some treatments are quite selective for either skin or gut conditions also highlights their crucial pathophysiologic differences. In the present review, a comprehensive comparison of risk factors, pathogenesis links, and therapeutic strategies for psoriasis and IBD is presented. Specific emphasis is placed on the role of the immune cell species and inflammatory mediators participating in the pathogenesis of these diseases.

Animal models of inflammatory bowel disease: how useful are they really?

PURPOSE OF REVIEW

Inflammatory bowel diseases (IBDs) are idiopathic chronic relapsing disorders of the gastrointestinal tract of unknown origin, characterized by heterogeneity and a multifactorial nature of their pathogenesis. Despite the recent improved options for treatment, patients with IBD still have an impaired quality of life, and require hospitalization and surgery. This review examines the contribution of animal models to the understanding and treatment of IBD.

RECENT FINDINGS

During the last decades, a large number of experimental models of intestinal inflammation have been developed. These models have proved to be helpful tools for obtaining new insights in the pathogenesis of the disease and for the preclinical evaluation of new therapies. However, even with the development of many new animal models in recent years, there are still limitations in the study of IBD because of lack of suitable animal models to cover all the requirements of basic research and preclinical studies.

SUMMARY

There is a need for a better interpretation of the data we obtain from the study of IBD animal models, in order to better understand the underlying pathogenetic mechanisms and improve the quality of the preclinical studies, and to develop more appropriate models to cover the research requirements.