Biologic agents for IBD: practical insights

Trends and Factors Associated with Hospitalization Costs for Inflammatory Bowel Disease in the United States

BACKGROUND

Few studies have addressed recent trends in hospitalization costs for inflammatory bowel disease (IBD).

OBJECTIVE

We explored trends and described patient and hospital factors associated with hospitalization costs for IBD.

METHODS

Using data from the 2003-2014 National Inpatient Sample for adults aged ≥ 18 years, we estimated costs using multivariable linear models and assessed linear trends by time periods using piecewise linear regressions.

RESULTS

In 2014, there were an estimated 56,290 hospitalizations for Crohn's disease (CD), with a mean cost of US$11,345 and median cost of US$7592; and 33,585 hospitalizations for ulcerative colitis (UC), with a mean cost of US$13,412 and median cost of US$8873. Higher costs were observed among Hispanic [adjusted cost ratio (ACR) = 1.07; 95% confidence interval (CI) = 1.00-1.14; p = 0.04] or other non-Hispanic (ACR = 1.09; 95% CI = 1.02-1.17; p = 0.01) CD patients than for non-Hispanic White CD patients. For UC patients, higher costs were observed among men (ACR = 1.09; 95% CI = 1.05-1.13; p < 0.001) compared with women and among patients aged 35-44 years, 45-54 years, and 55-64 years compared with those aged 18-24 years. Among all patients, factors associated with higher costs included higher household income, more comorbidities, and hospitals that were government nonfederal versus private, were large versus small, and were located in the West versus Northeast regions. From 2003 to 2008, total costs increased annually by 3% for CD (1.03; 95% CI = 1.02-1.05; p < 0.001) and 4% for UC (1.04; 95% CI = 1.02-1.06; p < 0.001), but remained unchanged from 2008 to 2014.

CONCLUSIONS

The findings are important to identify IBD patients with higher hospitalization costs and to inform policy plans on hospital resource allocation.

Patient and physician preferences for attributes of biologic medications for severe asthma

OBJECTIVE

Despite the increased availability of biologic treatments indicated for severe asthma, patient and physician preferences for these medications remains largely unknown. The purpose of this study was to understand perceptions of biologic therapies, barriers to care with biologic medications, and preferences for biologic therapy attributes.

METHODS

This mixed-methods study involved quantitative surveys and qualitative telephone interviews with patients and physicians from the United States. Participants described preferences for relevant attributes, and barriers to use of biologic medications. Participants rated, ranked, and indicated importance of preferences for different levels of key attributes including: mode of administration, administration setting, dosing frequency, number of injections, and time to onset of effect. Other attributes unique to each group were also included.

RESULTS

A total of 47 patients and 25 physicians participated. Patients ranked out-of-pocket costs, mode of administration, time to onset of efficacy, and administration setting as the most important attributes. Physicians ranked mode of administration, time to onset of efficacy, dosing frequency, and insurance reimbursement/access as most important. Both groups expressed preferences for less frequent administrations (Q8W over Q4W or Q2W) (all P<0.01) and subcutaneous (SC) over intravenous injection (both P<0.0001). Key patient barriers to biologic medications include location of treatment, administration time, scheduling, cost/insurance coverage, number of injections, and mode of administration. Physicians identified patient candidacy, convincing patients, administration setting, mode of administration, cost, and administrative burden as key barriers to initiating therapy; and efficacy, speed of onset, convenience of administration, cost, and patient compliance as barriers to staying on therapy.

CONCLUSIONS

Patients and physicians expressed strong preferences for less frequent dosing, SC administration, and faster onset. Cost/insurance coverage and convenience issues were key barriers to use. Increased awareness and understanding of preferences and barriers may be useful in facilitating physician-patient conversations with the goal of individualizing treatment.

Treatment with P28GST, a schistosome-derived enzyme, after acute colitis induction in mice: Decrease of intestinal inflammation associated with a down regulation of Th1/Th17 responses

Background

P28GST, a 28Kd glutathione S-transferase enzymatic protein derived from a schistosome helminth prevents experimental colitis when administered subcutaneously in the presence of adjuvant by decreasing pro-inflammatory Th1/Th17 response. Given the antioxidant properties of P28GST, we evaluated its anti-inflammatory potential when administered locally after colitis induction in the absence of adjuvant.

Methods

Colitis was induced in BALB/c mice by rectal administration of TNBS, followed by two intraperitoneal injections of P28GST at day 1 and day 2. Mice were sacrificed 48h after TNBS administration and evaluated for macroscopic and histological scores, myeloperoxidase (MPO) quantification and cytokine messenger RNA expression in the colonic tissues.

Results

Both clinical and histological scores significantly decreased in mice treated with P28GST at 5 or 50μg/kg when compared to vehicle- treated mice. A significant reduction of MPO was detected in colonic tissues from P28GST–treated mice, similarly to mice treated with methylprednisolone as the reference treatment. Pro-inflammatory cytokines TNF, IL-1β, and IL-6, mRNA as well as serum levels were down-regulated in mice colonic tissues treated with P28GST at 5 or 50μg/kg. In addition, a significant decrease of mRNA expression levels of T-bet, and ROR-γ, respective markers of Th1 and Th17 cells was observed. Whereas no significant effect was detected on Gata3 mRNA, a marker of Th2 cells, the Arg/iNOS mRNA levels significantly increased in P28GST-treated mice, suggesting the induction of M2 macrophages.

Conclusions

These findings provide evidence that P28GST injected locally after colitis induction induces a potent decrease of colitis inflammation in mice, associated to downregulation of Th1/Th17 response, and induction of anti-inflammatory alternatively activated macrophages.

A real-world, long-term experience on effectiveness and safety of vedolizumab in adult patients with inflammatory bowel disease: The Cross Pennine study

BACKGROUND

Real-life data on vedolizumab effectiveness in inflammatory bowel disease (IBD) are still emerging. Data on the comparative safety of the gut selective profile are of particular interest.

AIMS

To assess clinical outcome and safety in IBD patients treated with vedolizumab.

METHODS

We retrospectively collected data of patients treated with vedolizumab at eight UK hospitals (August 2014-January 2018). Clinical response and remission at 14 and 52 weeks evaluated through Physician Global Assessment (PGA) and adverse events were recorded. Possible predictors of clinical response were examined.

RESULTS

Two hundred and three IBD patients (mean treatment 16 ± 8 months) were included. Of these, 135 patients (mean age 40.6 ± 16.0 years; F:M 1.9:1) had CD and 68 (mean age 44.5 ± 18.1 years; F:M 1:1.2) had UC. According to PGA, 106/135 (78.5%) CD and 62/68 (91.2%) UC patients (p = 0.02) had a clinical response/remission at 14 weeks, whereas 76/119 (63.9%) CD and 52/63 (82.5%) UC patients (p < 0.01) showed a sustained response or remission at 52 weeks, with a high adherence rate (97%). No predictors of clinical response were found. The cumulative incidence of infectious diseases was 11.9 per 100 person-years.

CONCLUSION

Vedolizumab is an effective therapy for inducing and maintaining remission of IBD, with better results for UC, and with a good safety profile.

Anti-TNF-α Therapy Suppresses Proinflammatory Activities of Mucosal Neutrophils in Inflammatory Bowel Disease

Neutrophils have been found to play an important role in the pathogenesis of inflammatory bowel disease (IBD), and anti-TNF-α mAb (i.e., infliximab) therapy is demonstrated to be effective in the induction of clinical remission and mucosal healing in these patients. However, how anti-TNF-α mAb regulates the functions of neutrophils is still unknown. Herein, we found that anti-TNF-α therapy significantly downregulated infiltration of neutrophils in inflamed mucosa of IBD patients. Importantly, anti-TNF-α mAb could inhibit neutrophils to produce proinflammatory mediators, such as ROS, calprotectin, IL-8, IL-6, and TNF-α. These data indicate that TNF-α plays a critical role in the induction of mucosal inflammatory response, and that blockade of TNF-α modulates intestinal homeostasis through balancing immune responses of neutrophils.

Immuno-PET of Innate Immune Markers CD11b and IL-1β Detects Inflammation in Murine Colitis

Inflammatory bowel disease (IBD) is a chronic relapsing and remitting inflammatory disease of the gastrointestinal tract. The diagnosis and monitoring of IBD are reliant on endoscopy, which is invasive and does not provide information on specific mediators. Symptom flare in IBD is associated with increased activation of innate immune pathways. Immuno-PET approaches have previously demonstrated the ability to detect colitis; however, a direct comparison of antibodies targeted to innate immune mediators and cells has not been done. We aimed to compare immuno-PET of antibodies to IL-1β and CD11b against standard ¹⁸F-FDG and MRI approaches to detect colonic inflammation. Methods: Colonic concentrations of IL-1β and myeloperoxidase were determined by ELISA, and colonic infiltration by CD11b-positive CD3-negative innate immune cells was determined by flow cytometry and compared between healthy and dextran sodium sulphate-treated colitic mice. PET of ⁸⁹Zr-lα-IL-1β, ⁸⁹Zr-α-CD11b, and ¹⁸F-FDG was compared by volume-of-interest analysis and with MRI by region-of-interest analysis. Imaging results were confirmed by ex vivo biodistribution analysis. Results: Colonic inflammation was associated with impaired colonic epithelial barrier permeability, increased colonic IL-1β and myeloperoxidase concentrations, and increased CD11b-positive CD3-negative innate immune cell infiltration into the colon. ⁸⁹Zr-α-IL-1β and ⁸⁹Zr-α-CD11b immuno-PET detected colonic inflammation, as did ¹⁸F-FDG, and all PET tracers were more sensitive than MRI. Although ¹⁸F-FDG volumes of interest correlated with colitis severity and a strong trend was observed with ⁸⁹Zr-α-IL-1β, no correlation was observed for ⁸⁹Zr-α-CD11b or MRI. ⁸⁹Zr-α-IL-1β was distributed mainly to the gastrointestinal tract, whereas ⁸⁹Zr-α-CD11b was distributed to more tissue types. Conclusion: Immuno-PET using antibodies directed to innate immune markers detected colonic inflammation, with ⁸⁹Zr-α-IL-1β providing a more tissue-specific signal than ⁸⁹Zr-α-CD11b. Development of these technologies for human subjects will potentially provide a less invasive approach than endoscopy for diagnosing and monitoring IBD.

Etrolizumab versus infliximab in the treatment of induction phase of ulcerative colitis: A systematic review and indirect comparison

OBJECTIVES

There is still a need to develop new effective medications for the treatment of ulcerative colitis, particularly for patients who are intolerant or resistant to first line therapies. This article compared the efficacy and safety of etrolizumab and infliximab in moderate to severe ulcerative colitis.

METHODS

This meta-analysis was performed according to the PRISMA statement protocol. A systematic literature search of three major bibliographic databases (Scopus, PubMed, and Cochran) was performed until June 30, 2018. This review included studies that evaluated the efficacy of etrolizumab or infliximab in ulcerative colitis and were placebo controlled randomized trials. Pooled data from each treatment were indirectly compared using Bucher's method.

RESULTS

Seven trials were sufficiently homogeneous to be used for indirect comparison of the induction phase of the treatment. There were no significant differences in clinical remission and serious adverse events between etrolizumab and infliximab. Moreover, adverse events of etrolizumab were significantly less than those of infliximab. However, further trials are required to compare other parameters of efficacy such as the clinical response and mucosal healing of etrolizumab with infliximab in anti-TNF alpha naïve patients.

Trends of Medication Usage and Associated Outcomes for Taiwanese Patients with Inflammatory Bowel Disease from 2001 to 2015

BACKGROUND

No nationwide, long-term follow-up study has assessed medication-associated outcomes for Asian patients with inflammatory bowel disease (IBD). This study examined medication-associated outcomes for Taiwanese patients with IBD.

METHODS

In this nationwide cohort study, 3806 patients who had received catastrophic illness registration for IBD from 2001 to 2015 were enrolled.

RESULTS

A higher accumulated dosage of 5-aminosalicylic acid (5-ASA) was associated with decreased risks of hospitalization (hazard ratio (HR) = 0.6) and operation (HR = 0.5). Thiopurine was associated with increased risks of hospitalization (HR = 2.1 in the high-dosage group) and tuberculosis (TB; HR = 3.6) reactivation but not with operation risk. A higher accumulated dosage of anti-TNF-α agents was associated with increased risks of hospitalization (HR = 3.3), operation (HR = 2.9), hepatitis B (HR = 4.3), and TB (HR = 5.1) reactivation. Corticosteroids were associated with increased risks of hospitalization (HR = 3.5 in the high-dosage group), risk of operation, hepatitis B (HR = 2.8) and TB (HR = 2.8) reactivation.

CONCLUSIONS

5-ASA usage is associated with decreased risks of hospitalization and operation for patients with IBD, whereas thiopurine, corticosteroids, and anti-TNF-α agents are associated with increased risks of hospitalization and hepatitis B and TB reactivation.

Localization of TNF alpha in ileocolonic biopsies of patients with inflammatory bowel disease

BACKGROUND

Although antitumor necrosis factor alfa (TNFα) agents are widely used to treat patients with inflammatory bowel diseases (IBD) - both Crohn's disease (CD) and ulcerative colitis (UC) - there is still some uncertainty in the cell type expressing TNFα in human ileo-colonic segments.

AIMS

We investigated the immunohistochemical (IHC) expression of TNFα in the ileo-colonic segments of patients with both active CD and UC, to establish its anatomic and cellular localization in the inflamed sites. Our aim was to identify patients potentially resistant to anti TNFα agents.

PATIENTS AND METHODS

Ileo-colonic slides of complete histological mapping of patients with CD and UC before any treatment was started were obtained, and serial sections assessed for TNFα expression, together with IHC markers for lymphocytes, macrophages, and plasma cells.

RESULTS

TNFα was expressed in almost all inflamed segments of IBD patients, albeit with different strength, and was present, in addition to lymphocytes and, to a lesser extent, to macrophages, in plasma cells, where it had a strong positivity, as also demonstrated by colocalization of specific IHC staining. The expression of TNFα was mostly focal in CD patients and more diffuse in UC patients, likely due to the different patterns of inflammation (transmural and mucosal) of the two entities.

CONCLUSIONS

In IBD, TNFα is strongly expressed also in plasma cells, and it is easily evidenced by conventional IHC techniques. It remains to be established whether this observation might be useful in future to establish in routine biopsy samples whether patients may be responsive to treatments toward this cytokine.

The state of the art on treatment of Crohn's disease

Crohn's disease (CD) is a chronic, progressive, and destructive disease of the gastrointestinal tract. Although its incidence appears to be stable or decreasing in most countries in the North America and Europe, the incidence is rising rapidly in Asian countries. Immunomodulators and biologics are increasingly used to avoid long-term bowel damage and subsequent disability. Therapeutic drug monitoring facilitates optimizing thiopurines and anti-TNFs use. New biologic agents targeting various pathological pathways of CD are blooming in recent years, and the high cost of biologics and expiration of patents for several biologic agents have driven the utility of biosimilars for CD treatment. Here, the literature regarding the efficacy, safety, and withdrawal of the drugs, as well as the evolution of therapeutic targets will be reviewed.

Preoperative Ustekinumab Treatment Is Not Associated With Increased Postoperative Complications in Crohn's Disease: A Canadian Multi-Centre Observational Cohort Study

BACKGROUND

Ustekinumab (UST), an anti-IL12/23 inhibitor is indicated for moderate-to-severe Crohn's disease (CD). However, it is unclear if patients treated with UST are at increased risk for postoperative complications.

AIM

To evaluate the postoperative safety outcomes in UST-treated CD patients.

METHODS

A multicentre cohort study of UST-treated CD patients at two tertiary care centres (University of Calgary, University of Alberta, Canada) undergoing abdominal surgery between 2009 and 2016 was performed. Postoperative outcomes were compared against a control cohort of anti-TNF-treated patients over the same time-period. The primary outcome was occurrence of postoperative complications up to six months postoperatively, stratified by timing (early <30 days vs. late complications ≥30 days).

RESULTS

Twenty UST-treated patients and 40 anti-TNF-treated patients were included with a median preoperative treatment exposure of 6.5 months and 18 months, respectively (p=0.01). Bowel obstruction was the most common surgical indication in both cohorts. UST-treated patients were more likely to require an ostomy (70.0% vs. 12.5%, p<0.001) and be on combination therapy with either systemic corticosteroids or concurrent immunomodulators (azathioprine or methotrexate) (25.0% vs. 2.5%, p=0.01). Despite the increased concomitant use of immunosuppression in the UST-treated cohort, there were no significant differences in early or late postoperative wound infections (1/20 in UST-cohort, 2/40 in anti-TNF cohort, p=1.00), anastomotic leak (0/20 in UST-cohort, 3/40 in anti-TNF cohort, p=0.54), or postoperative ileus/obstruction (3/20 in UST-cohort, 4/40 in anti-TNF cohort, p=0.67).

CONCLUSIONS

CD patients receiving preoperative UST did not experience an increase in postoperative complications, despite increased use of concurrent immunosuppression.

Positioning of old and new biologicals and small molecules in the treatment of inflammatory bowel diseases

The past decade has brought substantial advances in the management of inflammatory bowel diseases (IBD). The introduction of tumor necrosis factor (TNF) antagonists, evidence for the value of combination therapy, the recognition of targeting lymphocyte trafficking and activation as a viable treatment, and the need for early treatment of high-risk patients are all fundamental concepts for current modern IBD treatment algorithms. In this article, authors review the existing data on approved biologicals and small molecules as well as provide insight on the current positioning of approved therapies. Patient stratification for the selection of specific therapies, therapeutic targets and patient monitoring will be discussed as well. The therapeutic armamentarium for IBD is expanding as novel and more targeted therapies become available. In the absence of comparative trials, positioning these agents is becoming difficult. Emerging concepts for the future will include an emphasis on the development of algorithms which will facilitate a greater understanding of the positioning of novel biological drugs and small molecules in order to best tailor therapy to the patient. In the interim, anti-TNF therapy remains an important component of IBD therapy with the most real-life evidence and should be considered as first-line therapy in patients with complicated Crohn’s disease and in acute-severe ulcerative colitis. The safety and efficacy of these ‘older’ anti-TNF therapies can be optimized by adhering to therapeutic algorithms which combine clinical and objective markers of disease severity and response to therapy.

Advances in Imaging Specific Mediators of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is characterized by chronic remitting and relapsing inflammation of the lower gastrointestinal tract. The etiology underlying IBD remains unknown, but it is thought to involve a hypersensitive immune response to environmental antigens, including the microbiota. Diagnosis and monitoring of IBD is heavily reliant on endoscopy, which is invasive and does not provide information regarding specific mediators. This review describes recent developments in imaging of IBD with a focus on positron emission tomography (PET) and single-photon emission computed tomography (SPECT) of inflammatory mediators, and how these developments may be applied to the microbiota.

Herb-partitioned moxibustion alleviates colon injuries in ulcerative colitis rats

AIM

To observe the effect of herb-partitioned moxibustion (HPM) on expression of colonic cytokines in ulcerative colitis (UC) rats.

METHODS

A UC rat model was established by protein immunization in combination with topical chemical stimulation. Rats in the HPM group (n = 8) received HPM at bilateral Tianshu (ST25) points. The gross injury and pathological scores of the colon were recorded. The expression profile of colonic cytokines was assayed using the protein microarray technique. Specific differential cytokines were selected and verified by ELISA. The corresponding UniProt Accessions of the differentially expressed cytokines were retrieved in the UniProt database. The pathways involved were analyzed with the help of the KEGG PATHWAY database. The DAVID database was used for functional cluster and pathway analysis.

RESULTS

HPM improved colon injuries in UC rats, manifested by accelerated repair of ulcers and alleviation of inflammation, and the gross injury and pathological scores both significantly decreased (P < 0.01). Fold change > 1.3 or < 0.77 was taken as the screening standard. There were 77 down-regulated and 9 up-regulated differentially expressed colonic cytokines in the HPM group compared with the model group, and expression of 20 differed significantly (P < 0.05). Twelve of the 20 significantly differentially expressed cytokines [β-catenin, interleukin-1 receptor 6 (IL-1R6), IL-1β, B7-1, nerve growth factor receptor, AMP-activated protein kinase-α1, neuropilin-2, orexin A, adipocyte differentiation-related protein, IL-2, Fas and FasL] were up-regulated in the model group (n = 3, compared with the normal group) but down-regulated in the HPM group (n = 3, compared with the model group). Functional cluster analysis showed that the differentially expressed colonic cytokines in the HPM group regulated apoptosis and protein phosphorylation. KEGG pathway analysis showed that 52 down-regulated and 7 up-regulated differentially expressed colonic cytokines in the HPM group had pathways. The pathways that interacted between the cytokines and their receptors accounted for the largest proportion (28 of the down-regulated and 5 of the up-regulated cytokines).

CONCLUSION

HPM promotes the repair of colon injuries in UC rats, which is related to the regulation of several abnormally expressed cytokines.

Cost-effectiveness of ustekinumab in moderate to severe Crohn's disease in Sweden

BACKGROUND

Human monoclonal antibody ustekinumab is a novel Crohn's disease (CD) treatment blocking pro-inflammatory cytokines interleukin-12 and 23. The study's objective was to assess cost-effectiveness of ustekinumab in moderate to severely active CD in Sweden.

METHODS

A cost-effectiveness model with an induction phase decision-tree structure and a maintenance phase Markov cohort structure was constructed. CD was represented by five health-states: remission, mild, moderate-severe, surgery and death. Ustekinumab was compared to adalimumab in patients who had failed conventional care, some of which had tried TNF-alpha-inhibitor(s) without experiencing treatment failure or side effects ("conventional care failure population") and to vedolizumab in patients previously failing TNF-alpha-inhibitor treatment. Discontinuation probabilities, utilities and ustekinumab induction efficacy were sourced from phase-III trials. Maintenance and comparator efficacy came from network-meta and treatment-sequence analyses. Resource use and unit costs were derived from literature and validated by clinical experts. The analysis had a societal perspective, a life-time time-horizon, and 2-year treatment duration. The results robustness was tested in univariate and probabilistic sensitivity analyses. Cost-effectiveness was estimated using quality-adjusted life-years (QALYs).

RESULTS

Ustekinumab dominated adalimumab in conventional care failure population (costs: - €6984, QALYs: + 0.232). In TNF-alpha-inhibitor failure population ustekinumab accrued 0.133 more QALYs than vedolizumab, yielding a €30,282 incremental cost-effectiveness ratio. Results were sensitive to decreasing the time horizon and increased treatment duration. At Swedish reference willingness-to-pay of €63,000 (SEK 600,000), ustekinumab had 94% probability of being cost-effective versus adalimumab, and 72% versus vedolizumab.

CONCLUSIONS

Results indicate ustekinumab dominates adalimumab in conventional care failure population, and is cost-effective versus vedolizumab in TNF-alpha-inhibitor failure population.

Systematic Review with Network Meta-Analysis: Efficacy of Induction Therapy with a Second Biological Agent in Anti-TNF-Experienced Crohn's Disease Patients

Background and Aim

Crohn's disease (CD) is a chronic inflammatory condition of the gastrointestinal tract with the potential to progress to a severe debilitating state. Treatment with biological agents is highly efficient, improving both short-term outcomes and long-term prognosis. Nonetheless, up to 60% of patients receiving biological therapy will exhibit nonresponse at some point. The optimal management of such patients is not clearly defined. Besides traditional anti-TNF agents (infliximab, adalimumab, and certolizumab), alternative biological therapies (natalizumab, vedolizumab, and ustekinumab) are currently available for the treatment of CD. Our aim was to analyze all available evidence regarding efficacy of a second biological in "biological-treatment-experienced" patients.

Methods

A systematic review of the literature was conducted using specific criteria for selecting relevant randomized clinical trials evaluating response to administration of secondary biological therapy in "anti-TNF-experienced" CD patients. Data from these studies was used to perform (a) traditional meta-analysis to ascertain the effect of secondary treatment versus placebo and (b) network meta-analysis to compare indirectly the efficacy of available biological agents.

Results

Out of initially 977 studies, only eight were included for analysis, providing a total of 1281 treated and 733 placebo-receiving CD patients. Treatment with a second biological was found to be superior to placebo for both induction of remission (OR 2.2, 95% CI 1.7 to 3) and response (OR 1.9, 95% CI 1.5 to 2.5), with global rates of 24% and 42%, respectively (placebo rate: 11% and 27%, p < 0.0001 for both). Indirect comparisons performed with network meta-analysis suggest no specific agent is clearly superior to others, with relatively better results observed for adalimumab in inducing disease remission.

Conclusion

In anti-TNF-experienced CD patients, secondary biological administration may be efficient, while no specific agent seems to outperform the others. Further research is needed to identify optimal management strategies for this challenging subset of patients.

TNFα inhibitors exacerbate Mycobacterium paratuberculosis infection in tissue culture: a rationale for poor response of patients with Crohn's disease to current approved therapy

Background The role of Mycobacteriumavium subspecies paratuberculosis (MAP) in Crohn’s disease (CD) is increasingly accepted as evident by detection of the bacteria in the blood and intestinal tissue from patients with CD, and by supporting data from several open-label anti-MAP treatment studies. Tumour necrosis factor alpha (TNFα) monoclonal antibodies (anti-TNFα) have been widely used for CD treatment. Despite the short-term benefit of anti-TNFα in controlling CD symptoms, most patients suffer from detrimental adverse effects, including higher susceptibility to mycobacterial infections. Methods We investigated the effect of recombinant cytokines and anti-TNFα therapeutics on macrophages infected with clinical MAP strain isolated from CD patient blood. MAP viability was measured in macrophages pulsed with PEGylated and non-PEGylated anti-TNFα monoclonal antibodies at concentrations 0 to 50 µg/mL and with rTNFα, rIL-6, rIL-12, rIL-23 and IFNγ at a final concentration of 1000 U/mL. Expression of proinflammatory cytokines was measured by RT-PCR following MAP infection.

Results Both PEGylated and non-PEGylated forms of anti-TNFα increased MAP viability by nearly 1.5 logs. rIL-6 and rIL-12 induced MAP viability at 5.42±0.25 and 4.79±0.14 log CFU/mL, respectively. In contrast, rTNFα reduced MAP survival in infected macrophages by 2.63 logs. Expression of TNFα, IL-6 and IL-12 was upregulated threefold following MAP or M. tuberculosis infection compared with other bacterial strains (p<0.05), while expression of IL-23 and IFNγ was not significant after MAP infection.

Conclusion The data indicate MAP-positive patients with CD receiving anti-TNFα treatment could result in favourable conditions for MAP infection, which explains the poor response of many patients with CD to anti-TNFα therapy.

Role of biologics and biosimilars in inflammatory bowel disease: current trends and future perspectives

Inflammatory bowel disease (IBD) is an idiopathic chronic inflammatory disease of the gastrointestinal system. The spectrum is of predominantly two types, namely, ulcerative colitis and Crohn’s disease. The incidence of IBD has been increasing steadily since 1990, and so the number of agents used in their treatment. Biologics that are derived partly or completely from living biological sources such as animals and humans have become widely available, which provide therapeutic benefits to the IBD patients. Currently, monoclonal antibodies against tumor necrosis factor-alpha (infliximab, adalimumab, certolizumab, and golimumab), integrins (vedolizumab and natalizumab), and interleukin (IL)-12 and IL-23 antagonists (ustekinumab) are approved for use in IBD. Biosimilars of infliximab and adalimumab are also available for the treatment of IBD. This review summarizes the clinical pharmacology, studies leading to their approval, overall indications and their use in IBD, usage in pregnancy and lactation, and the adverse effects of these agents. This review also summarizes the recent advances and future perspectives specific to biologics and biosimilars in IBD.

Should we use anti-tumor necrosis factor agents or vedolizumab as first-line biological therapy in ulcerative colitis?

Randomized controlled trials with direct comparisons between the different available biological agents in ulcerative colitis are lacking. The comparative efficacy, safety and tolerability, patient profile, patient preference and costs should be taken into account when choosing an appropriate first-line biological. Tumor necrosis factor antagonists have a systemic mode of action, while vedolizumab is mainly gut-selective, and this influences the clinical profile of both treatment options. Tofacitinib will further expand the therapeutic armamentarium in ulcerative colitis. Results of ongoing head-to-head trials between biological agents are likely to change clinical practice in the near future. Biomarkers that predict response to different treatment options in an individual patient are warranted.

Neutrophils and neutrophil extracellular traps in the liver and gastrointestinal system

Neutrophil extracellular traps (NETs) have an important role during infection by helping neutrophils to capture and kill pathogens. However, evidence is accumulating that uncontrolled or excessive production of NETs is related to the exacerbation of inflammation and the development of autoimmunity, cancer metastasis and inappropriate thrombosis. In this Review, we focus on the role of NETs in the liver and gastrointestinal system, outlining their protective and pathological effects. The latest mechanistic insights in NET formation, interactions between microorganisms and NETs and the relationship between neutrophil subtypes and their functions are also discussed. Additionally, we describe the potential importance of NET-related molecules, including cell-free DNA and hypercitrullinated histones, as biomarkers and targets for therapeutic intervention in gastrointestinal diseases.

Immunopathogenesis of inflammatory bowel disease and mechanisms of biological therapies

Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract with a multifactorial pathophysiology. Full comprehension of IBD pathology is still out of reach and, therefore, treatment is far from ideal. Nevertheless, components involved in IBD pathogenesis including environmental, genetic, microbial, and immunological factors are continuously being investigated and the improved knowledge contributes to the development of new therapies. In this article we review the aspects of the immunopathogenesis of IBD, with focus on mucosal immunity, and discuss mechanisms of action for current and emerging biological therapies.

Risk of Malignancy in a Nationwide Cohort of Elderly Inflammatory Bowel Disease Patients

BACKGROUND

Management of elderly inflammatory bowel disease (IBD) patients (≥ 65 years of age) is complicated due to many factors, including a higher risk of cancer, which may impact therapeutic decisions.

OBJECTIVE

The aim of this study was to determine the risk of cancer among elderly IBD patients compared with younger IBD patients. Additionally, the absolute risk of malignancy and factors contributing to it were evaluated, and therapeutic patterns among the elderly were assessed.

METHODS

This retrospective cohort study extracted data from the Truven Health Analytics MarketScan^® database. Among adult IBD patients who were free of cancer before starting on corticosteroids, immunomodulators, or biologics, a Cox model for time to cancer was fitted that adjusted for several covariates, including time-dependent treatment. Baseline results were evaluated by age group, as were the incidence of cancer and the distribution of cancer subtypes.

RESULTS

The elderly IBD cohort (n = 8788) had a higher prevalence of cancer and several other ailments before starting treatment, relative to the younger IBD cohort aged 18-64 years (n = 54,971). During follow-up, the elderly IBD cohort experienced a higher incidence of malignancy, confirmed by a hazard ratio (HR) of 3.04 (95% confidence interval [CI] 2.71-3.41) from the Cox model fit. The risk of cancer was also significantly associated with male sex (HR 0.82 female), duration of disease (HR 1.08), several comorbidities and corticosteroid use (HR 1.35), but not with the use of immunomodulators or biologics. Non-Hodgkin's lymphoma, urinary tract malignancy, and prostate, lung, and female breast cancers were observed more commonly in this elderly IBD cohort when compared with the same age group in the Surveillance, Epidemiology, and End Results (SEER) database.

CONCLUSIONS

The elderly with IBD have a higher risk of malignancy when compared with younger IBD patients and the general age-matched population, with certain cancers being more common among these patients.

Can a Conversation Between Mesenchymal Stromal Cells and Macrophages Solve the Crisis in the Inflamed Intestine?

Inflammatory bowel disease (IBD) is a group of chronic inflammatory conditions of the gastrointestinal tract characterized by an exacerbated mucosal immune response. Macrophages play pivotal roles in the maintenance of gut homeostasis but they are also implicated in the pathogenesis of IBD. They are highly plastic cells and their activation state depends on the local environment. In the healthy intestine, resident macrophages display an M2 phenotype characterized by inflammatory energy, while inflammatory M1 macrophages dominate in the inflamed intestinal mucosa. In this regard, modifying the balance of macrophage populations into an M2 phenotype has emerged as a new therapeutic approach in IBD. Multipotent mesenchymal stromal cells (MSCs) have been proposed as a promising cell-therapy for the treatment of IBD, considering their immunomodulatory and tissue regenerative potential. Numerous preclinical studies have shown that MSCs can induce immunomodulatory macrophages and have demonstrated that their therapeutic efficacy in experimental colitis is mediated by macrophages with an M2-like phenotype. However, some issues have not been clarified yet, including the importance of MSC homing to the inflamed colon and/or lymphoid organs, their optimal route of administration or whether they are effective as living or dead cells. In contrast, the mechanisms behind the effect of MSCs in human IBD are not known and more data are needed regarding the effect of MSCs on macrophage polarization that would support the observation reported in the experimental models. Nevertheless, MSCs have emerged as a novel method to treat IBD that has already been proven safe and with clinical benefits that could be administered in combination with the currently used pharmacological treatments.

Epithelial-mesenchymal transition in Crohn's disease

Crohn's disease (CD) is often accompanied by the complications of intestinal strictures and fistulas. These complications remain obstacles in CD treatment. In recent years, the importance of epithelial-mesenchymal transition in the pathogenesis of CD-associated fistulas and intestinal fibrosis has become apparent. Epithelial-mesenchymal transition refers to a dynamic change, wherein epithelial cells lose their polarity and adherence and acquire migratory function and fibroblast features. During formation of CD-associated fistulas, intestinal epithelial cells dislocate from the basement membrane and migrate to the lining of the fistula tracts, where they convert into transitional cells as a compensatory response under the insufficient wound healing condition. In CD-associated intestinal fibrosis, epithelial-mesenchymal transition may serve as a source of new fibroblasts and consequently lead to overproduction of extracellular matrix. In this review, we present current knowledge of epithelial-mesenchymal transition and its role in the pathogenesis of CD in order to highlight new therapy targets for the associated complications.

Bone marrow lympho-myeloid malfunction in obesity requires precursor cell-autonomous TLR4

Obesity, a prevalent condition in adults and children, impairs bone marrow (BM) function. However, the underlying mechanisms are unclear. Here, we show that obese mice exhibit poor emergency immune responses in a toll-like receptor 4 (TLR4)-dependent manner. Canonical myeloid genes (Csf1r, Spi1, Runx1) are enhanced, and lymphoid genes (Flt3, Tcf3, Ebf1) are reduced. Using adoptive transfer and mixed BM chimera approaches we demonstrate that myeloid>lymphoid bias arises after 6 weeks of high-fat diet and depends on precursor cell-autonomous TLR4. Further, lean mice exposed to the TLR4 ligand lipopolysaccharide (LPS) at doses similar to that detectable in obese serum recapitulates BM lympho-myeloid alterations. Together, these results establish a mechanistic contribution of BM cell-intrinsic TLR4 to obesity-driven BM malfunction and demonstrate the importance of LPS. Our findings raises important questions about the impact of maternal obesity and endotoxemia to fetal hematopoiesis, as fetal immune precursors are also sensitive to TLR4 signals.

Obesity can affect bone marrow cell differentiation and the generation of myeloid and lymphoid cells. Here, the authors show that diet and obesity, as well as low-dose lipopolysaccharide, can alter Toll-like receptor 4 signaling bone marrow cells to skew the myeloid-lymphoid homeostasis in mice.

Population-based cohort study on comparative effectiveness and safety of biologics in inflammatory bowel disease

Background

The comparison of effectiveness and safety of anti-tumor necrosis factor-alpha agents for the treatment of inflammatory bowel disease (IBD) is relevant for clinical practice and stakeholders.

Objective

The objective of this study was to compare the risk of abdominal surgery, steroid utilization, and hospitalization for infection in Crohn’s disease (CD) or ulcerative colitis (UC) patients newly treated with infliximab (IFX) or adalimumab (ADA).

Methods

A retrospective population-based cohort study was performed using health information systems data from Lazio region, Italy. Patients with CD or UC diagnosis were enrolled at first prescription of IFX or ADA during 2008–2014 (index date). Only new drug users were followed for 2 years from the index date. IFX versus ADA adjusted hazard ratios were calculated applying “intention-to-treat” approach, controlling for several characteristics and stratifying the analysis on steroid use according to previous drug utilization. Sensitivity analyses were performed according to “as-treated” approach, adjusting for propensity score, censoring at switching or discontinuation, and evaluating different lengths of follow-up periods.

Results

We enrolled 1,432 IBD patients (42% and 83% exposed to IFX for CD and UC, respectively). In both diseases, treatment effects did not differ in any outcome considered, and sensitivity analyses confirmed the results from the main analysis.

Conclusion

In our population-based cohort study, effectiveness and safety data in new users of ADA or IFX with CD or UC were comparable for the outcomes we tested.

Travel and biologic therapy: travel-related infection risk, vaccine response and recommendations

BACKGROUND

Biologic therapy has revolutionized the management of refractory chronic autoimmune and auto-inflammatory disease, as well as several malignancies, providing rapid symptomatic relief and/or disease remission. Patients receiving biologic therapies have an improved quality of life, facilitating travel to exotic destinations and potentially placing them at risk of a range of infections. For each biologic agent, we review associated travel-related infection risk and expected travel vaccine response and effectiveness.

METHODS

A PUBMED search [vaccination OR vaccine] AND/OR ['specific vaccine'] AND/OR [immunology OR immune response OR response] AND [biologic OR biological OR biologic agent] was performed. A review of the literature was performed in order to develop recommendations on vaccination for patients in receipt of biologic therapy travelling to high-risk travel destinations.

RESULTS

There is a paucity of literature in this area, however, it is apparent that travel-related infection risk is increased in patients on biologic therapy and when illness occurs they are at a higher risk of complication and hospitalization. Patients in receipt of biologic agents are deemed as having a high level of immunosuppression-live vaccines, including the yellow fever vaccine, are contraindicated. Inactivated vaccines are considered safe; however, vaccine response can be attenuated by the patient's biologic therapy, thereby resulting in reduced vaccine effectiveness and protection.

CONCLUSIONS

Best practice requires a collaborative approach between the patient's primary healthcare physician, relevant specialist and travel medicine expert, who should all be familiar with the immunosuppressive and immunomodulatory effects resulting from the biologic therapies. Timing of vaccines should be carefully planned, and if possible, vaccination provided well before established immunosuppression.

Optimizing Selection of Biologics in Inflammatory Bowel Disease: Development of an Online Patient Decision Aid Using Conjoint Analysis

OBJECTIVES

Recent drug approvals have increased the availability of biologic therapies for inflammatory bowel disease (IBD), making it difficult for patients with ulcerative colitis (UC) and Crohn's disease (CD) to navigate treatment options. Here we developed a conjoint analysis to examine patient decision-making surrounding biologic medicines for IBD. We used the results to create an online patient decision aid that generates a unique "preferences report" for each patient to assist with shared decision-making with their provider.

METHODS

We administered an adaptive choice-based conjoint survey to IBD patients that quantifies the relative importance of biologic attributes (e.g., efficacy, side effect profile, mode of administration, and mechanism of action) in decision making. The conjoint software determined individual patient preferences by calculating part-worth utilities for each attribute. We conducted regression analyses to determine if demographic and disease characteristics (e.g., type of IBD and severity) predicted how patients made decisions.

RESULTS

640 patients completed the survey (UC=304; CD=336). In regression analyses, demographics and IBD characteristics did not predict individual patient preferences; the main exception was IBD type. When compared to UC, CD patients were more likely to report side effect profile as most important (odds ratio (OR) 1.63, 95% confidence interval (CI) 1.16-2.30). Conversely, those with UC were more likely to value therapeutic efficacy (OR 1.41, 95% CI 1.01-2.00).

CONCLUSIONS

Biologic decision-making is highly personalized; demographic and disease characteristics poorly predict individual preferences, indicating that IBD patients are unique and difficult to statistically categorize. The online decision tool resulting from this study (www.ibdandme.org) may be used by patients to support shared decision-making and optimize personalized biologic selection with their provider.

Systematic review with network meta-analysis: first- and second-line pharmacotherapy for moderate-severe ulcerative colitis

BACKGROUND

There are limited data to inform positioning of agents for treating moderate-severe ulcerative colitis (UC).

AIM

To assess comparative efficacy and safety of different therapies as first-line (biologic-naïve) and second-line (prior exposure to anti-tumour necrosis factor(TNF)-α) agents for moderate-severe UC, through a systematic review and network meta-analysis, and appraise quality of evidence (QoE) using grading of recommendations, assessment, development and evaluation (GRADE) approach.

METHODS

We identified randomised controlled trials (RCTs) in adults with moderate-severe UC treated with anti-TNF agents, anti-integrin agents and janus kinase (JAK) inhibitors, as first-line or second-line agents, and compared with placebo or another active agent. Efficacy outcomes were induction/maintenance of remission and mucosal healing; and safety outcomes were serious adverse events and infections. Network meta-analyses were performed, and ranking was assessed using surface under the cumulative ranking (SUCRA) probabilities.

RESULTS

In biologic-naïve patients (12 trials, no head-to-head comparisons), infliximab and vedolizumab were ranked highest for induction of clinical remission (infliximab: odds ratio [OR], 4.10 [95% confidence intervals [CI], 2.58-6.52]; SUCRA,0.85; vedolizumab:SUCRA,0.82) and mucosal healing (infliximab:SUCRA,0.91; vedolizumab:SUCRA,0.81) (moderate QoE). In patients with prior anti-TNF exposure (4 trials, no head-to-head comparisons), tofacitinib was ranked highest for induction of clinical remission (OR, 11.88 [2.32-60.89]; SUCRA, 0.96) and mucosal healing (moderate QoE). Differences in trial design limited comparability of trials of maintenance therapy for efficacy. Vedolizumab was ranked safest in terms of serious adverse events (SUCRA, 0.91), and infection (SUCRA, 0.75) in maintenance trials.

CONCLUSIONS

Infliximab and vedolizumab are ranked highest as first-line agents, and tofacitinib is ranked highest as second-line agent, for induction of remission and mucosal healing in patients with moderate-severe UC, based on indirect comparisons. Head-to-head trials are warranted to inform clinical decision-making with greater confidence.

Discontinuation of Biological Treatments in Inflammatory Bowel Disease: A Concise Pragmatic Review

Despite the proven efficacy of biological drugs for inflammatory bowel disease, these therapies are costly and do carry some risks, providing incentive for exploring strategies to discontinue therapy in patients with prolonged remission. We presently review multiple cohort studies indicating the overall risk of relapse after stopping an anti-tumor necrosis factor (TNF) in inflammatory bowel disease patients is roughly 40% at 12 months after therapy cessation. Despite methodological differences across studies, it appears that patients without deep remission (ie, patients with endoscopic or biomarker evidence of inflammation) are at increased risk of relapse after stopping anti-TNF, as are those with high-adequate levels of anti-TNF before stopping. In patients who relapse after anti-TNF cessation, retreatment with the same biological seems to reinduce clinical response in most patients. Immunological reasons responsible for this high success rate for retreatment are elucidated, but resorting to retreatment also implies a small but finite risk of a severe flare leading to surgery, which should be borne in mind. Thus, stopping attempts should probably be reserved for patients with low risk for severe outcome should a relapse occur. Proactive endoscopic monitoring after drug cessation is imperative to reduce these risks. The recently introduced concept of treatment-cycles is discussed, along with a pragmatic algorithm of decision tree for therapy discontinuation in the selected appropriate patients.

Integrin α4β7 Blockade Preferentially Impacts CCR6+ Lymphocyte Subsets in Blood and Mucosal Tissues of Naive Rhesus Macaques

Infusion of a simianized anti-α₄β₇ mAb (Rh-α₄β₇) just before and following SIV infection protected rhesus macaques from developing AIDS and partially from vaginal SIV acquisition. Recently, short-term treatment with Rh-α₄β₇ in combination with cART was found to lead to prolonged viral suppression after withdrawal of all therapeutic interventions. The humanized form of Rh-α₄β₇, vedolizumab, is a highly effective treatment for inflammatory bowel disease. To clarify the mechanism of action of Rh-α₄β₇, naive macaques were infused with Rh-α₄β₇ and sampled in blood and tissues before and after treatment to monitor several immune cell subsets. In blood, Rh-α₄β₇ increased the CD4⁺ and CD8⁺ T cell counts, but not B cell counts, and preferentially increased CCR6⁺ subsets while decreasing CD103⁺ and CD69⁺ lymphocytes. In mucosal tissues, surprisingly, Rh-α₄β₇ did not impact integrin α₄⁺ cells, but decreased the frequencies of CCR6⁺ and CD69⁺ CD4⁺ T cells and, in the gut, Rh-α₄β₇ transiently decreased the frequency of memory and IgA⁺ B cells. In summary, even in the absence of inflammation, Rh-α₄β₇ impacted selected immune cell subsets in different tissues. These data provide new insights into the mechanisms by which Rh-α₄β₇ may mediate its effect in SIV-infected macaques with implications for understanding the effect of treatment with vedolizumab in patients with inflammatory bowel disease.

A review on biosimilar infliximab, CT-P13, in the treatment of inflammatory bowel disease

The introduction of biological agents has led to significant changes in the treatment of inflammatory bowel disease (IBD). The relatively high price of infliximab (IFX) and the expiration of the patents led to the introduction of biosimilar agents. CT-P13 was the first IFX biosimilar approved in the same indications as the reference product; however, the approval was based on randomized clinical trials conducted in patients with rheumatoid arthritis and ankylosing spondylitis. In the past 2-3 years, new findings from prospective observational studies supported the short-, medium- and long-term clinical efficacy and safety of CT-P13 in patients with IBD. This review summarized the clinical use and efficacy of the first biosimilar IFX, CT-P13, in the treatment of IBD.

The Efficacy and Safety of Golimumab as Third- or Fourth-Line Anti-TNF Therapy in Patients with Refractory Crohn's Disease: A Case Series

Background

The TNF-α antagonist golimumab is approved for the treatment of ulcerative colitis but not for Crohn's disease (CD). We herein report a case series of 8 difficult-to-treat patients with severe and refractory CD receiving golimumab as an off-label rescue medication and fourth-line anti-TNF agent in our tertiary referral inflammatory bowel disease center.

Methods

We performed a retrospective analysis of clinical, biochemical, and radiological as well as endoscopic parameters. The patients all suffered from severe refractory CD with ongoing symptoms. Moreover, all 8 patients had previously been treated with all 3 other TNF-α antagonists approved for CD in Switzerland (infliximab, adalimumab, and certolizumab pegol) without durable clinical response.

Results

Three out of 8 patients showed a primary nonresponse. Among the 5 patients responding after induction, 1 patient showed a loss of response, and in 1 patient, treatment was terminated due to side effects. Three patients have a continuous clinical response under golimumab. We did not observe any severe adverse events during golimumab administration.

Conclusions

A considerable fraction of this highly selected subgroup of difficult-to-treat CD patients responded to golimumab, indicating a promising potential for refractory CD patients, including those with multiple previous anti-TNF exposures.

Metabonomics uncovers a reversible proatherogenic lipid profile during infliximab therapy of inflammatory bowel disease

BACKGROUND

One-third of inflammatory bowel disease (IBD) patients show no response to infliximab (IFX) induction therapy, and approximately half of patients responding become unresponsive over time. Thus, identification of potential treatment response biomarkers are of great clinical significance. This study employs spectroscopy-based metabolic profiling of serum from patients with IBD treated with IFX and healthy subjects (1) to substantiate the use of spectroscopy as a semi-invasive diagnostic tool, (2) to identify potential biomarkers of treatment response and (3) to characterise the metabolic changes during management of patients with tumour necrosis factor-α inhibitors.

METHODS

Successive serum samples collected during IFX induction treatment (weeks 0, 2, 6 and 14) from 87 IBD patients and 37 controls were analysed by ¹H nuclear magnetic resonance (NMR) spectroscopy. Data were analysed with principal components analysis and orthogonal projection to latent structures discriminant analysis using SIMCA-P+ v12 and MATLAB.

RESULTS

Metabolic profiles were significantly different between active ulcerative colitis and controls, active Crohn's disease and controls, and quiescent Crohn's disease and controls. Metabolites holding differential power belonged primarily to lipids and phospholipids with proatherogenic characteristics and metabolites in the pyruvate metabolism, suggestive of an intense inflammation-driven energy demand. IBD patients not responding to IFX were identified as a potentially distinct group based on their metabolic profile, although no applicable response biomarkers could be singled out in the current setting.

CONCLUSION

¹H NMR spectroscopy of serum samples is a powerful semi-invasive diagnostic tool in flaring IBD. With its use, we provide unique insights into the metabolic changes taking place during induction treatment with IFX. Of distinct clinical relevance is the identification of a reversible proatherogenic lipid profile in IBD patients with active disease, which partially explains the increased risk of cardiovascular disease associated with IBD.

A systematic review of cost-effectiveness studies comparing conventional, biological and surgical interventions for inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic disease placing a large health and economic burden on health systems worldwide. The treatment landscape is complex with multiple strategies to induce and maintain remission while avoiding long-term complications. The extent to which rising treatment costs, due to expensive biologic agents, are offset by improved outcomes and fewer hospitalisations and surgeries needs to be evaluated. This systematic review aimed to assess the cost-effectiveness of treatment strategies for IBD.

MATERIALS AND METHODS

A systematic literature search was performed in March 2017 to identify economic evaluations of pharmacological and surgical interventions, for adults diagnosed with Crohn's disease (CD) or ulcerative colitis (UC). Costs and incremental cost-effectiveness ratios (ICERs) were adjusted to reflect 2015 purchasing power parity (PPP). Risk of bias assessments and a narrative synthesis of individual study findings are presented.

RESULTS

Forty-nine articles were included; 24 on CD and 25 on UC. Infliximab and adalimumab induction and maintenance treatments were cost-effective compared to standard care in patients with moderate or severe CD; however, in patients with conventional-drug refractory CD, fistulising CD and for maintenance of surgically-induced remission ICERs were above acceptable cost-effectiveness thresholds. In mild UC, induction of remission using high dose mesalazine was dominant compared to standard dose. In UC refractory to conventional treatments, infliximab and adalimumab induction and maintenance treatment were not cost-effective compared to standard care; however, ICERs for treatment with vedolizumab and surgery were favourable.

CONCLUSIONS

We found that, in general, while biologic agents helped improve outcomes, they incurred high costs and therefore were not cost-effective, particularly for use as maintenance therapy. The cost-effectiveness of biologic agents may improve as market prices fall and with the introduction of biosimilars. Future research should identify optimal treatment strategies reflecting routine clinical practice, incorporate indirect costs and evaluate lifetime costs and benefits.

The intestinal microbiota determines the colitis-inducing potential of T-bet-deficient Th cells in mice

Conflicting evidence has been provided as to whether induction of intestinal inflammation by adoptive transfer of naïve T cells into Rag^-/- mice requires expression of the transcription factor T-bet by the T cells. Here, we formally show that the intestinal microbiota composition of the Rag^-/- recipient determines whether or not T-bet-deficient Th cells can induce colitis and we have resolved the differences of the two microbiomes, permissive or non-permissive to T-bet-independent colitis. Our data highlight the dominance of the microbiota over particular T cell differentiation programs in the pathogenesis of chronic intestinal inflammation.

Therapeutic Drug Monitoring During Induction of Anti-Tumor Necrosis Factor Therapy in Inflammatory Bowel Disease: Defining a Therapeutic Drug Window

Anti-tumor necrosis factor (TNF) therapy has revolutionized the treatment of inflammatory bowel disease (IBD). However, up to 30% of patients with IBD show no clinical benefit and are defined as having a primary nonresponse. Primary nonresponse to a biologic can be attributed to either pharmacokinetic or pharmacodynamic issues, such as those involved in secondary loss of response. Pharmacokinetic issues are linked to undetectable or subtherapeutic drug concentrations because of either an accelerated non-immune-mediated clearance or immunogenicity and the development of antidrug antibodies, whereas pharmacodynamic issues are likely related to "non-TNF driven" disease. Therapeutic drug monitoring (TDM), defined as the evaluation of drug concentrations and antidrug antibodies, has been proven effective for optimizing anti-TNF therapy in IBD. Nevertheless, most of the data for TDM relate to patients losing response during maintenance therapy, whereas much less is known about the therapeutic drug window and use of TDM during anti-TNF induction therapy. Recent exposure-response relationship studies, though, demonstrate that high serum anti-TNF drug concentrations during and early after induction therapy are associated with favorable therapeutic outcomes in IBD. This suggests that early optimization of anti-TNF therapy may prevent some of the primary nonresponse related to pharmacokinetic issues (low drug concentrations) and lead to better short- and long-term outcomes. This review will focus on the role of TDM during the induction phase of anti-TNF therapy.

Colonic Phenotypes Are Associated with Poorer Response to Anti-TNF Therapies in Patients with IBD

BACKGROUND

Although anti-tumor necrosis factor (TNF) agents are effective in patients with inflammatory bowel disease (IBD), many patients either do not respond to anti-TNF treatment or lose response over time. The aim of this study was to determine factors associated with response to anti-TNF therapy in IBD.

METHODS

Patients with Crohn's disease (CD) or ulcerative colitis who had consented to participate in a genetics registry and been treated with anti-TNF agents were evaluated retrospectively and categorized as primary nonresponders or secondary nonresponders. We evaluated clinical, serological, and genetic characteristics associated with primary nonresponse or time to loss of response to anti-TNF agents.

RESULTS

We included 314 CD (51 [16.2%] primary nonresponders and 179 [57.0%] secondary nonresponders) and 145 subjects with ulcerative colitis (43 [29.7%] primary nonresponders and 74 [51.0%] secondary nonresponders). Colonic involvement (P = 0.017; odds ratio = 8.0) and anti-TNF monotherapy (P = 0.017; odds ratio = 4.9) were associated in a multivariate analysis with primary nonresponse to anti-TNF agents in CD. In addition, higher anti-nuclear cytoplasmic antibody levels (P = 0.019; hazard ratio = 1.01) in CD, anti-nuclear cytoplasmic antibody positivity (P = 0.038; hazard ratio = 1.6) in ulcerative colitis, and a positive family history of IBD (P = 0.044; hazard ratio = 1.3) in all patients with IBD were associated with time to loss of response to anti-TNF agents. Furthermore, various known IBD susceptibility single-nucleotide polymorphisms and additional variants in immune-mediated genes were shown to be associated with primary nonresponse or time to loss of response.

CONCLUSIONS

Our results may help to optimize the use of anti-TNF agents in clinical practice and position these therapies appropriately as clinicians strive for a more personalized approach to managing IBD.

Understanding the Cautions and Contraindications of Immunomodulator and Biologic Therapies for Use in Inflammatory Bowel Disease

Ulcerative colitis and Crohn's disease are chronic inflammatory bowel diseases for which there are no cures. These diseases are immunopathogenic, and medical treatment is centered on the temperance of a dysregulated immune response to allow mucosal healing and prevent the sequelae of fistulation and stenosis. Accordingly, the armamentarium of medications, which has expanded immensely in recent history, is not without significant infectious and neoplastic risks. Many of these untoward effects can be mitigated by screening and avoidance of contraindicated medications. This review seeks to highlight the cautions for use of immunomodulators, anticytokine, and α4-integrin antagonists. The potential adverse events are further complicated by substantial heterogeneity in disease phenotype in the inflammatory bowel disease population. Large patient registries and databases provide considerable experience and knowledge to calculate the incidence of safety outcomes. To identify rarer outcomes after prolonged therapy, more prospective studies and continued adverse event reporting will aid safe application and minimize potential harms.

Genetic polymorphisms predict response to anti-tumor necrosis factor treatment in Crohn’s disease

AIM

To investigate genetic factors that might help define which Crohn’s disease (CD) patients are likely to benefit from anti-tumor necrosis factor (TNF) therapy.

METHODS

This was a prospective cohort study. Patients were recruited from a university digestive disease practice database. We included CD patients who received anti-TNF therapy, had available medical records (with information on treatment duration and efficacy) and who consented to participation. Patients with allergic reactions were excluded. Patients were grouped as ever-responders or non-responders. Genomic DNA was extracted from peripheral blood, and 7 single nucleotide polymorphisms (SNPs) were assessed. The main outcome measure (following exposure to the drug) was response to therapy. The patient genotypes were assessed as the predictors of outcome. Possible confounders and effect modifiers included age, gender, race, and socioeconomic status disease, as well as disease characteristics (such as Montreal criteria).

RESULTS

121 patients were included. Twenty-one were non-responders, and 100 were ever-responders. Fas ligand SNP (rs763110) genotype frequencies, TNF gene -308 SNP (rs1800629) genotype frequencies, and their combination, were significantly different between groups on multivariable analysis controlling for Montreal disease behavior and perianal disease. The odds of a patient with a Fas ligand CC genotype being a non-responder were four-fold higher as compared to a TC or TT genotype (P = 0.009, OR = 4.30, 95%CI: 1.45-12.80). The presence of the A (minor) TNF gene -308 allele correlated with three-fold higher odds of being a non-responder (P = 0.049, OR = 2.88, 95%CI: 1.01-8.22). Patients with the combination of the Fas ligand CC genotype and the TNF -308 A allele had nearly five-fold higher odds of being a non-responder (P = 0.015, OR = 4.76, 95%CI: 1.35-16.77). No difference was seen for the remaining SNPs.

CONCLUSION

The Fas-ligand SNP and TNF gene -308 SNP are associated with anti-TNF treatment response in CD and may help select patients likely to benefit from therapy.

Calprotectin and the Magnitude of Antibodies to Infliximab in Clinically-stable Ulcerative Colitis Patients are More Relevant Than Infliximab Trough Levels and Pharmacokinetics for Therapeutic Escalation

Although infliximab (IFX) is an efficient therapy for ulcerative colitis (UC) patients, a considerably high rate of therapeutic failures still occurs. This study aimed at a better understanding of IFX pharmacokinetics and pharmacodynamics among clinically-asymptomatic UC patients. This was a multicentric and prospective study involving 65 UC patients in the maintenance phase of IFX therapy. There were no significant differences between patients with positive and negative clinical, endoscopic and histological outcomes concerning their IFX trough levels (TLs), area under the IFX concentration vs. time curve (AUC), clearance and antibodies to infliximab (ATI) levels. However, the need to undergo therapeutic escalation later in disease development was significantly associated with higher ATI levels (2.62μg/mL vs. 1.15μg/mL, p=0.028). Moreover, and after adjusting for disease severity, the HR (hazard ratio) for therapeutic escalation was significantly decreased for patients with an ATI concentration below 3μg/mL (HR=0.119, p=0.010), and increased for patients with fecal calprotectin (FC) level above 250μg/g (HR=9.309, p=0.018). In clinically-stable UC patients, IFX pharmacokinetic features cannot predict therapeutic response on a short-term basis. However, high levels of ATIs or FC may be indicative of a future therapeutic escalation.

Outcomes After Primary Infliximab Treatment Failure in Inflammatory Bowel Disease

BACKGROUND

Primary infliximab treatment failure is common in patients with inflammatory bowel disease and represents a challenge to clinicians. Treatment options are limited. This study assessed the prognosis, defined as surgery-free survival, in patients with primary infliximab treatment failure as compared to patients without primary failure (initial responders). Furthermore, this study assessed the specter of medical therapies used after primary infliximab treatment failure along with treatment outcomes.

METHODS

Retrospective, observational, cohort study of patients with inflammatory bowel disease treated with infliximab as first-line anti-tumor necrosis factor treatment at a tertiary center. Primary infliximab treatment failure was defined as no clinical improvement during infliximab induction therapy resulting in discontinuation of infliximab therapy.

RESULTS

A total of 560 patients (Crohn's disease n = 353 and ulcerative colitis n = 207) were treated with infliximab. Among these, 81 (15%) had primary infliximab treatment failure after a median of 3 infusions (weeks 0, 2, and 6) (interquartile range 2-4). The median surgery-free survival was 196 days from first infusion. One year after primary infliximab treatment failure, the majority of patients (n = 51, 63%) had inflammatory bowel disease-related surgery (Crohn's disease n = 19, 58%; ulcerative colitis n = 32, 67%; P = 0.49). There was a markedly increased risk of surgery in patients with primary infliximab treatment failure as compared to initial responders: odds ratio 6.3 (3.8-10.6), P < 0.0001. Among 30 patients handled by medical therapies, 16 (53%) still had active disease 1 year after primary infliximab treatment failure.

CONCLUSIONS

Primary infliximab treatment failure is associated with poor outcome including high risk of surgery or sustained active disease despite medical interventions.

Endocytosis of pro-inflammatory cytokine receptors and its relevance for signal transduction

The pro-inflammatory cytokines tumor necrosis factor (TNF), interleukin-1 (IL-1) and interleukin-6 (IL-6) are key players of the innate and adaptive immunity. Their activity needs to be tightly controlled to allow the initiation of an appropriate immune response as defense mechanism against pathogens or tissue injury. Excessive or sustained signaling of either of these cytokines leads to severe diseases, including rheumatoid arthritis, inflammatory bowel diseases (Crohn's disease, ulcerative colitis), steatohepatitis, periodic fevers and even cancer. Studies carried out in the last 30 years have emphasized that an elaborate control system for each of these cytokines exists. Here, we summarize what is currently known about the involvement of receptor endocytosis in the regulation of these pro-inflammatory cytokines' signaling cascades. Particularly in the last few years it was shown that this cellular process is far more than a mere feedback mechanism to clear cytokines from the circulation and to shut off their signal transduction.

CT-P13: design, development, and place in therapy

The introduction of biological agents has revolutionized the management of many life-threatening and debilitating immune-mediated diseases. Because of the high cost of biological drugs and their patent expiration, the market has opened to biosimilar agents, copy versions of the originators, which can lead to reduced health care expenditure and increase treatment access worldwide. CT-P13 is the first biosimilar of infliximab (IFX) and has been approved for the same indications as its originator drug. It obtained regulatory approval by the European Medicines Agency in September 2013 and by the US Food and Drug Administration in April 2016. The Phase I and Phase III clinical trials conducted in ankylosing spondylitis and rheumatoid arthritis have demonstrated pharmacokinetic and efficacy equivalence with comparable safety and immunogenicity to IFX. For these reasons, the use of CT-P13 has been extrapolated also to inflammatory bowel disease. There have been some initial concerns regarding the use of CT-P13 in inflammatory bowel disease patients, because of the lack of randomized controlled trials. However, emerging real-world data have further confirmed the comparability between CT-P13 and its reference product in terms of efficacy, safety, and immunogenicity, in patients naïve to the anti-tumor necrosis factor alpha agents and after switching from IFX, and will be summarized in this review.

Treatment Persistence for Infliximab Versus Adalimumab in Crohn's Disease: A 14-Year Single-Center Experience

BACKGROUND

Infliximab (IFX) and adalimumab (ADA) are widely used in the treatment of patients with Crohn's disease (CD). There are few published data on the treatment persistence of IFX and ADA in patients with CD.

METHODS

We aimed to compare the persistence rates of IFX versus ADA as first- and second-line tumor necrosis factor antagonist (anti-TNF), to identify factors potentially associated with persistence, and to evaluate reasons for treatment withdrawal in CD patients. We performed a retrospective, single-center cohort study of CD patients treated with IFX or ADA for at least 6 months between June 2002 and May 2016.

RESULTS

The median duration of follow-up was 5.4 years. For first-line anti-TNF agent, data on 487 patients with CD were analyzed. The mean (SD) duration of persistence was 3.6 (3.1) years and 2.5 (2.0) years in the IFX and ADA subgroups, respectively; the intergroup difference was not significant (P = 0.219). Factors associated with lower persistence were female sex (P = 0.0005) and stricturing behavior (P = 0.008). For second-line anti-TNF agent, data on 134 patients were analyzed. The mean (SD) duration of persistence was 2.4 (1.9) years and 2.6 (2.1) years in the IFX and ADA subgroups, respectively; again, the intergroup difference was not significant (P = 0.488). Age under 37.2 was the only factor associated with lower persistence (P = 0.016) for second-line treatment with an anti-TNF agent.

CONCLUSIONS

IFX and ADA show similar levels of persistence as first- and second-line anti-TNF treatments. Female sex and stricturing behavior were associated with poor persistence of first-line treatments, whereas age was the only factor associated with poor persistence of second-line treatments.

Schiff base complexes of copper and zinc as potential anti-colitic compounds

The design, synthesis and activity of polymodal compounds for the treatment of inflammatory bowel disease are reported. The compounds, being based on a metal-Schiff base motif, are designed to degrade during intestinal transit to release the bioactive components in the gut. The compounds have been developed sequential with the biomodal compounds combining copper or zinc with a salicylaldehyde adduct. These compounds were tested in a formalin induced colonic inflammation model in BK:A mice. From these studies a trimodal compound based on a zinc Schiff base analogue of sulfasalazine was designed. This was tested against a trinitrobenzenesulfonic acid (TNB) induced colitic model in Wistar rats. The use of two models allows us to test our compounds in both an acute and a chronic model. The trimodal compound reported is observed to provide anticolitic properties in the chronic TNB induced colitis model commensurate with that of SASP. However, the design of trimodal compound still has the capacity for further development. This the platform reported may offer a route into compounds which can markedly outperform the anti-colitic properties of SASP.

Crohn's disease

Crohn's disease is a chronic inflammatory disease of the gastrointestinal tract, with increasing incidence worldwide. Crohn's disease might result from a complex interplay between genetic susceptibility, environmental factors, and altered gut microbiota, leading to dysregulated innate and adaptive immune responses. The typical clinical scenario is a young patient presenting with abdominal pain, chronic diarrhoea, weight loss, and fatigue. Assessment of disease extent and of prognostic factors for complications is paramount to guide therapeutic decisions. Current strategies aim for deep and long-lasting remission, with the goal of preventing complications, such as surgery, and blocking disease progression. Central to these strategies is the introduction of early immunosuppression or combination therapy with biologicals in high-risk patients, combined with a tight and frequent control of inflammation, and adjustment of therapy on the basis of that assessment (treat to target strategy). The therapeutic armamentarium for Crohn's disease is expanding, and therefore the need to develop biomarkers that can predict response to therapies will become increasingly important for personalised medicine decisions in the near future. In this Seminar, we provide a physician-oriented overview of Crohn's disease in adults, ranging from epidemiology and cause to clinical diagnosis, natural history, patient stratification and clinical management, and ending with an overview of emerging therapies and future directions for research.

Cost-utility of biological treatment sequences for luminal Crohn's disease in Europe

BACKGROUND

This study aims to compare the cost-effectiveness of treatment sequences with available biologics, including adalimumab (ADA), biosimilar infliximab (bsIFX), originator infliximab (IFX) and vedolizumab (VEDO) for luminal Crohn's disease in nine European countries.

METHODS

A Markov-model was constructed to simulate five-year medical costs and quality-adjusted life years (QALYs). Data on clinical efficacy were obtained from randomised controlled trials. Country-specific unit costs, discount rates and a third-party payer perspective were applied.

RESULTS

The bsIFX versus conventional therapy resulted in the most favourable incremental cost-utility ratios (ICURs) ranging from €34,580 (Hungary) to €77,062/QALY (Sweden). Compared to bsIFX, the bsIFX-ADA sequence was more cost-effective than the bsIFX-VEDO sequence with ICURs varying between €70,277 (France) and €162,069/QALY (Germany). The ICURs of the bsIFX-ADA-VEDO sequence versus the bsIFX-ADA strategy were between €206,266 (The Netherlands) and €363,232/QALY (Spain).

CONCLUSION

We are the first to compare cost-effectiveness of multiple biological sequences for luminal Crohn's disease. Based on our findings, bsIFX can be recommended as a first-line treatment in patients unresponsive to conventional treatments. While biological sequences only slightly differ in their associated health gains, their costs vary greatly. The bsIFX-ADA-VEDO seems to be the most cost-effective sequence of the available biologics across Europe.