Assessing response and loss of response to biological therapies in IBD

IBD Patients with Primary or Secondary Nonresponse to Ustekinumab Benefit from Dose Escalation or Reinduction

Ustekinumab is a monoclonal antibody approved for the treatment of IBD. This drug has a well-established efficacy; however, patients may not respond or lose response. The availability of other biological therapies prompts the need for comparative data between different agents to suggest first- or second-line strategies. Aim of this review is to compare the effectiveness of ustekinumab to other biologics in Crohn's disease and ulcerative colitis, as well as report the available data on dose escalation and reinduction. A systematic electronic search of the English literature was performed up to November 2023, using Medline (PubMed), Web of Science, Scopus and the Cochrane Library. Conference proceedings were also screened. Out of 659 citations, 80 relevant articles were selected and included in the present narrative review. Head-to-head comparisons of different biological drugs are relatively scarce, mostly deriving from indirect comparison or retrospective studies. Overall available data indicate similar effectiveness in the treatment of IBD patients. Dose escalation and reinduction strategies are well documented, but the optimal treatment schedule is still to be defined. Response and remission rates vary in different studies, and a proportion of patients fail to achieve clinical and endoscopic outcomes. However, both approaches are effective and safe in nonresponders and secondary loss of response. IBD patients may benefit from dose escalation or reinduction. Both strategies prove effective in regaining response in a proportion of patients, avoiding unnecessary early switch. Head-to-head trials are still needed to determine the exact placement of this drug compared to other biologics.

Relationship between Ustekinumab trough concentrations and clinical, biochemical and endoscopic outcomes in Crohn's disease: A multi-center nationwide retrospective study (TARGET STUDY)

Ustekinumab has been shown to be effective in inducing and maintain clinical and endoscopic remission in Crohn disease (CD). We aim to assess whether ustekinumab trough levels are associated with improved outcomes in CD in real-life. We recruited patients with CD who were treated with ustekinumab for at least 6 months from January 2017 to June 2023. Patients received ustekinumab 6 mg/kg intravenous induction followed by 90 mg every 4-, 8-, or 12-weeks during maintenance were included. We assessed clinical, biochemical, and endoscopic outcomes. Trough concentrations of ustekinumab that were taken from week 42 to week 52 were measured. Primary outcome was to evaluate the relationship between ustekinumab trough concentrations and clinical remission, biochemical normalization, and endoscopic remission. Logistic regression was conducted to assess outcomes. A total of 137 patients with CD, median age of 32 years and 83 (60.6%) males. The median serum levels of ustekinumab measured was 7.2 mcg/mL (interquartile range [IQR] 3.1-9.6). Using Spearman correlation analysis, a strong negative correlation was observed between ustekinumab drug levels and simple endoscopic score (SES-CD) (r = -0.464, P < .001). Additionally, ustekinumab drug levels demonstrated substantial negative correlations with disease severity measured by Harvey-Bradshaw index (HBI) score (r = -0.582, P < .001), C-Reactive Protein (CRP) levels (r = -0.598, P < .001) and fecal calprotectin (FC) levels (r = -0.529, P < .001). A multivariable analysis adjusted for age, sex and body mass index (BMI) showed a significant association between ustekinumab serum drug levels and predefined outcomes. Ustekinumab serum drug level above 4.5 mcg/mL was associated with 24% increase in the likelihood of having an SES-CD score <3 (OR 1.24, confidence interval [CI] 1.12-1.37, P value < .001), 44% more likely to achieve HBI score <5 (OR 1.44, CI 1.26-1.65, P value < .001), 52% higher likelihood of CRP more than 10 (OR 1.52, CI 1.31-1.77, P < .001), and 42% increased likelihood of FC more than 250 (OR 1.42, CI 1.24-1.62, P < .001). Ustekinumab trough concentrations above 4.5 mcg/mL were associated with clinical, biochemical and endoscopic remission in CD. Prospective data is warranted to confirm these findings.

Precision medicine: Externally validated explainable AI support tool for predicting sustainability of infliximab and vedolizumab in ulcerative colitis

OBJECTIVE

Drug sustainability (DS), a surrogate marker for drug efficacy, is important, especially when aiming for precision medicine. However, it lacks reliable prediction methods.

AIMS

To develop and externally validate a web-based artificial intelligence(AI)-derived tool for predicting DS of infliximab and vedolizumab in patients with moderate-to-severe Ulcerative Colitis (UC).

METHODS

Data from three Israeli centers included infliximab or vedolizumab patients treated for >54 weeks. Sustainability meant no corticosteroids, hospitalizations or surgeries. Machine learning techniques predicted >54-week and overall DS using baseline clinical data.

RESULTS

The model was developed using data from 246 patients from Rabin Medical Center and externally validated on 67 patients from Rambam Health Care Campus and Sheba Medical Center. No significant difference in DS was observed across the datasets. Most patients were biologic-naïve and primarily treated with vedolizumab. The model performed well, with an area under the ROC curve of 0.86, and showed good accuracy (65.5 %-76.9 %) across the test sets.

CONCLUSIONS

The study introduces a novel, AI-based tool for predicting >54-week DS of infliximab and vedolizumab in moderate-to-severe UC, using baseline parameters. This can aid clinical decision-making in the framework of precision medicine, promising to optimize disease management while maintaining physician autonomy.

Approach to loss of response to advanced therapies in inflammatory bowel disease

BACKGROUND

Remarkable progress over the last decade has equipped clinicians with many options in the treatment of inflammatory bowel disease. Clinicians now have the unique opportunity to provide individualized treatment that can achieve and sustain remission in many patients. However, issues of primary non-response (PNR) and secondary loss of response (SLOR) to non-tumour necrosis factor inhibitor (TNFi) therapies remains a common problem. Specific issues include the choice of optimization of therapy, identifying when dose optimization will recapture response, establishing optimal dose for escalation and when to switch therapy.

AIM

To explores the issues of PNR and SLOR to non-TNFi therapies.

METHODS

This review explores the current evidence and literature to elucidate management options in cases of PNR/SLOR. It will also explore potential predictors for response following SLOR/PNR to therapies including the role of therapeutic drug monitoring (TDM).

RESULTS

In the setting of PNR and loss of response to alpha-beta7-integrin inhibitors and interleukin (IL)-12 and IL-23 inhibitors dose optimization is a reasonable option to capture response. For Janus kinase inhibitors dose optimization can be utilized to recapture response with loss of response.

CONCLUSION

The role of TDM in the setting of advanced non-TNFi therapies to identify patients who require dose optimization and as a predictor for clinical remission is not yet established and this remains an area that should be addressed in the future.

Assessing Progression of Biologic Therapies Based on Smoking Status in Patients With Crohn's Disease

BACKGROUND

Active smoking is a well-established risk factor for developing Crohn's disease (CD) and negatively impacts overall disease progression. Patients who start or continue smoking after CD diagnosis are at risk for poor outcomes, higher therapeutic requirements, and have higher rates of relapse. However, it remains unclear if the exposure to smoking leads to increased sequencing through treatment therapies, especially biologics.

METHODS

The Study of Prospective Adult Research Cohort with IBD (SPARC IBD) registry has been collecting patient-reported outcomes data in real-time, as well as laboratory, endoscopic, and pathologic samples from 17 tertiary referral centers since 2016. In this study, we conducted a retrospective review of the SPARC clinical registry collected between December 2016 and January 2021 from 1 participating site, the University of Maryland School of Medicine's Inflammatory Bowel Disease Program. A total of 619 patients were enrolled in the SPARC IBD database. Four hundred twenty-five patients with CD were included for initial review of completeness of data; of these, 144 patients were excluded due to missing data on smoking status and/or biologic treatment, resulting in a final cohort of 281 patients. We collected and analyzed baseline demographic and clinical characteristics. The final cohort was categorized into 3 exposure groups: current, former, and never smokers. Our outcome of interest was number biologics used, categorized into 3 groups: 0, 1, or ≥2 biologics.

RESULTS

One hundred seventy-two never smokers, 70 former smokers, and 39 current smokers were identified. Current, former, and never smokers had no statistically significant differences in number of biologics used (ie, biologic sequencing). However, statistically significant independent risk factors for increased sequencing of biologics were identified. These risk factors included female sex, ileocolonic disease location, younger age at diagnosis, and prolonged disease duration; none of these factors remained significant in adjusted analyses.

CONCLUSION

To date, this is the first study assessing the association of smoking and sequencing of biologics. Although current or former smokers were not found to sequence through more biologics when compared with never smokers, smoking is a well-established risk factor for poor health outcomes, and efforts should be made to counsel patients to quit. Further, additional research must be done to stratify risk to patients based on amount of tobacco exposure.

Single or continuous multiple intravenous re-induction in Crohn's disease patients who lost response to ustekinumab: Evidence from real-world data

BACKGROUND AND AIMS

Re-induction optimization of ustekinumab is effective in Crohn's disease (CD) patients who experienced a loss of response (LOR) to ustekinumab. However, whether continuous multiple intravenous optimization is better than single dose re-induction remains unknown. We aimed to compare effectiveness of two strategies in CD patients with LOR to ustekinumab.

METHODS

We retrospectively included CD patients who had LOR to standardized ustekinumab therapy. They were divided into three groups according to different times (one to three) for re-induction.

RESULTS

This study included 50, 26 and 22 of 98 eligible patients in one intravenous re-induction subgroup, double intravenous re-induction subgroup and three intravenous re-induction subgroup, respectively. At week 24, 67.3%, 75.5%, 56.6%, 69.8% and 61.2% of all achieved steriod free clinical remission, clinical response, endoscopic remission, endoscopic response and C-reactive protein normalization, respectively. No differences were found in all endpoints between three groups. Ustekinumab trough level at week 24 but not times of re-induction showed a tendency to predict clinical remission. No serious adverse events were found in this cohort.

CONCLUSION

Intravenous re-induction was safe and effective in CD patients who experienced LOR to ustekinumab. Trough level of ustekinumab but not times of intravenous re-induction may associated with clinical efficacy.

Therapeutic drug monitoring in inflammatory bowel diseases. Position statement of the Spanish Working Group on Crohn's Disease and Ulcerative Colitis

The treatment of inflammatory bowel disease has undergone a significant transformation following the introduction of biologic drugs. Thanks to these drugs, treatment goals have evolved from clinical response and remission to more ambitious objectives, such as endoscopic or radiologic remission. However, even though biologics are highly effective, a significant percentage of patients will not achieve an initial response or may lose it over time. We know that there is a direct relationship between the trough concentrations of the biologic and its therapeutic efficacy, with more demanding therapeutic goals requiring higher drug levels, and inadequate exposure being common. Therapeutic drug monitoring of biologic medications, along with pharmacokinetic models, provides us with the possibility of offering a personalized approach to treatment for patients with IBD. Over the past few years, relevant information has accumulated regarding its utility during or after induction, as well as in the maintenance of biologic treatment, in reactive or proactive strategies, and prior to withdrawal or treatment de-escalation. The aim of this document is to establish recommendations regarding the utility of therapeutic drug monitoring of biologics in patients with inflammatory bowel disease, in different clinical practice scenarios, and to identify areas where its utility is evident, promising, or controversial.

Exploring the Predictive Value of Gut Microbiome Signatures for Therapy Intensification in Patients With Inflammatory Bowel Disease: A 10-Year Follow-up Study

BACKGROUND

Inflammatory bowel diseases (IBDs) pose a significant challenge due to their diverse, often debilitating, and unpredictable clinical manifestations. The absence of prognostic tools to anticipate the future complications that require therapy intensification presents a substantial burden to patient private life and health. We aimed to explore whether the gut microbiome is a potential biomarker for future therapy intensification in a cohort of 90 IBD patients.

METHODS

We conducted whole-genome metagenomics sequencing on fecal samples from these patients, allowing us to profile the taxonomic and functional composition of their gut microbiomes. Additionally, we conducted a retrospective analysis of patients' electronic records over a period of 10 years following the sample collection and classified patients into (1) those requiring and (2) not requiring therapy intensification. Therapy intensification included medication escalation, intestinal resections, or a loss of response to a biological treatment. We applied gut microbiome diversity analysis, dissimilarity assessment, differential abundance analysis, and random forest modeling to establish associations between baseline microbiome profiles and future therapy intensification.

RESULTS

We identified 12 microbial species (eg, Roseburia hominis and Dialister invisus) and 16 functional pathways (eg, biosynthesis of L-citrulline and L-threonine) with significant correlations to future therapy intensifications. Random forest models using microbial species and pathways achieved areas under the curve of 0.75 and 0.72 for predicting therapy intensification.

CONCLUSIONS

The gut microbiome is a potential biomarker for therapy intensification in IBD patients and personalized management strategies. Further research should validate our findings in other cohorts to enhance the generalizability of these results.

Ustekinumab in the Treatment of Inflammatory Bowel Diseases: Evolving Paradigms

Inflammatory bowel diseases, comprising Crohn's disease (CD) and ulcerative colitis (UC), are chronic, relapsing, and remitting immune-mediated inflammatory diseases affecting the gastrointestinal tract. Ustekinumab (UST) is a monoclonal antibody that blocks the p40 subunit of the anti-interleukin (IL) 12/23. Pivotal trials (CERTIFI and UNITI-IM for CD, UNIFI for UC) established the efficacy of UST for the induction and maintenance of remission in both CD and UC, with the most favorable results in naïve patients to biologics. In recent years, a wealth of 'real-world' data has emerged supporting positive clinical, endoscopic, and histological outcomes in patients treated with UST, as well as reassuring safety data. More recently, the results of the first head-to-head trials of UST and tumor necrosis factor (TNF) antagonists were reported. Moreover, a number of studies exploring the role of UST in specific clinical settings, such as perianal CD, postoperative complications and recurrence, extraintestinal manifestations, chronic antibiotic-refractory pouchitis, and pregnancy, were reported. This review explores the results reported to date on UST, including those from pivotal trials, real-world data, and emerging studies regarding therapeutic drug monitoring and immunogenicity. The safety profile of UST was also reviewed.

Upadacitinib in Crohn's disease

INTRODUCTION

The small molecule and oral selective and reversible Janus kinase (JAK) inhibitor upadacitinib has been approved for the treatment of moderate to severe active Crohn's disease (CD) in adult patients since April 2023 by EMA/FDA.

AREAS COVERED

The approval is based on the two induction studies a maintenance study showing that upadacitinib induction and maintenance therapy was superior to placebo. The approval of upadacitinib in CD expands the therapeutic armamentarium for the management of inflammatory bowel diseases (IBD). Upadacitinib is the first and only JAK inhibitor approved in patients with CD and provides a novel mechanism of action and the first advanced oral treatment option for patients with CD. Upadacitinib is approved for the treatment of other immunologically mediated disorders, including ulcerative colitis, rheumatoid arthritis, psoriasis arthritis, axial spondylarthritis, ankylosing spondylitis, and atopic dermatitis. Treatment of atopic dermatitis has been approved from the age of 12 years.

EXPERT OPINION

Upadacitinib may cause relevant changes of our current treatment algorithms for Crohn's disease. Further real-world studies and head-to-head comparisons are needed to position upadacitinib in our current treatment algorithms for CD.

Clinical use of biologics for Crohn's disease in adults: lessons learned from real-world studies

INTRODUCTION

The therapeutic armamentarium for managing Crohn's disease (CD) has expanded significantly in recent decades. Several biologics with three different mechanisms of action [anti-tumor necrosis factor (TNF)-α, anti-integrin α4β7, and anti-IL 12/23] are currently available to manage CD.

AREA COVERED

This narrative review aims to summarize the most significant efficacy and safety data on the use of infliximab (IFX), adalimumab (ADA), vedolizumab (VDZ) and ustekinumab (UST) for the treatment of CD obtained from studies conducted in the real world (RW), compared to the results of randomized clinical trials (RCTs).

EXPERT OPINION

RW studies reported that biologic agents included in this analysis have higher remission rates and lower adverse event rates than findings from RCTs for treating patients with CD. All biological agents have proven effective and safe in RW studies, even when using biosimilars or switching to subcutaneous administration of the molecules for which they are available. Finally, anti-TNF-α agents, particularly IFX, have a higher rate of adverse events (AEs) than VDZ and UST. Therefore, patients at higher risk of AEs may benefit from other biologics than anti-TNF-α. However, further long-term RW studies are needed to confirm these findings.

Ustekinumab safety and effectiveness in patients with ulcerative colitis: results from a large real-life study

BACKGROUND

Ustekinumab (UST) is an interleukin-12/interleukin-23 receptor antagonist recently approved for treating ulcerative colitis (UC) but with limited real-world data. Therefore, we evaluated the effectiveness and safety of UST in patients with UC in a real-world setting.

RESEARCH DESIGN AND METHODS

This is a multicenter, retrospective, observational cohort study. The primary endpoints were the clinical remission rate (partial Mayo score, PMS, ≤1) and the safety of UST. Other endpoints were corticosteroid-free remission (CSFR) rate, clinical response rate (PMS reduction of at least 2 points), and fecal calprotectin (FC) reduction at week 24.

RESULTS

We included 256 consecutive patients with UC (M/F 139/117, median age 52). The clinical remission and clinical response rates at eight weeks were 18.7% (44/235) and 53.2% (125/235), respectively, and 27.6% (42/152) and 61.8% (94/152) at 24 weeks, respectively. At 24 weeks, CSFR was 20.3% (31/152), and FC significantly dropped at week 12 (p = 0.0004) and 24 (p = 0.038). At eight weeks, patients naïve or with one previous biologic treatment showed higher remission (p = 0.002) and clinical >response rates (p = 0.018) than patients previously treated with ≥ 2. Adverse events occurred in six patients (2.3%), whereas four patients (1.6%) underwent colectomy.

CONCLUSION

This real-world study shows that UST effectively and safely treats patients with UC.

Change in Biologic Class Promotes Endoscopic Remission Following Endoscopic Postoperative Crohn's Disease Recurrence

GOALS

Assess the outcomes of various therapeutic regimens to treat initial endoscopic postoperative recurrence despite biologic prophylaxis.

BACKGROUND

Postoperative biologic prophylaxis reduces postoperative Crohn's disease (CD) recurrence rates. Optimal treatment strategies for endoscopic recurrence have not been elucidated.

STUDY

Retrospective cohort study of adult CD patients who underwent ileocolonic resection between 2009 and 2020. Patients with endoscopic postoperative recurrence despite prophylactic biologic therapy and ≥1 subsequent colonoscopy were included. Treatment changes after recurrence were categorized as (1) therapy optimization or continuation or (2) new biologic class. The primary outcome was composite endoscopic or surgical recurrence at the time of or prior to subsequent follow-up colonoscopy.

RESULTS

Eighty-one CD patients with endoscopic recurrence (54.3% i2b, 22.2% i3, and 23.5% i4) despite biologic prophylaxis (86.4% anti-tumor necrosis factor, 8.6% vedolizumab, 4.9% ustekinumab) were included. Most patients received therapy optimization or continuation (76.3%, n=61) following recurrence compared to being started on a new biologic class. Sixty patients (N=48 therapy optimization; N=12 new biologic class) experienced composite recurrence (78.3% endoscopic, 21.7% surgical). On multivariable modeling, initiation of a new biologic class was associated with reduced risk for composite recurrence compared to therapy optimization or continuation (aOR: 0.26; P=0.04). Additionally, initiation of a new biologic class was associated with endoscopic improvement when adjusting for endoscopic severity at the time of recurrence (aOR: 3.4; P=0.05). On sensitivity analysis, a new biologic class was associated or trended with improved rates of endoscopic healing and composite recurrence when directly compared to therapy optimization or continuation.

CONCLUSION

In patients with CD who experience endoscopic recurrence despite biologic prophylaxis, changing the mechanism of biologic action may promote endoscopic improvement.

The HLA-DQA1*05 genotype does not influence the clinical response to ustekinumab and vedolizumab

BACKGROUND

the success of strategies with earlier anti-TNF drugs for the treatment of inflammatory bowel disease (IBD) have been shadowed by the development of anti-drug antibodies that reduce their effectiveness. The HLA-DQA1*05 allele has been shown to increase the risk of immunogenicity to anti-TNF drugs by approximately two-fold. The negative impact of this allele has not been fully investigated for newer biotherapies.

OBJECTIVE

whether the presence of the HLA-DQA1*05 allele is associated with a reduction of response to ustekinumab and vedolizumab was investigated.

MATERIAL AND METHODS

the impact of HLA-DQA1*05 on disease activity in 93 patients with IBD, treated with ustekinumab (n = 39) or vedolizumab (n = 54) was investigated in a retrospective cohort study. Treatment response and remission was assessed at 6 and 12 months for ustekinumab, and up to 18 and 24 months for vedolizumab, using Harvey-Bradshaw index (Crohn's disease) and Mayo score (ulcerative colitis).

RESULTS

the HLA-DQA1*05 allele was found in 35.9 % and 38.9 % of patients treated with ustekinumab and vedolizumab, respectively. Clinical response was not affected by the presence of the HLA-DQA1*05 allele for both treatment groups.

CONCLUSIONS

in contrast to anti-TNF drugs, HLA-DQA1*05 presence does not correlate with the decreased response to ustekinumab or vedolizumab.

Sarcopenia assessed by computed tomography or magnetic resonance imaging is associated with the loss of response to biologic therapies in adult patients with Crohn's disease

Sarcopenia occurs in patients with Crohn's disease (CD). However, the association between sarcopenia and loss of response (LOR) to biologic agents remains unclear. This study explored such an association in CD patients. This retrospective study included 94 CD patients who received biologic therapy. The skeletal muscle cross-sectional area at the third lumbar was assessed by computed tomography or magnetic resonance imaging for sarcopenia evaluation. A LOR was defined by fecal calprotectin (FC) < 250 μg/g or >50% reduction from baseline levels or other factors, such as the used agent being replaced by other biologic agents. The association between sarcopenia and LOR was assessed by logistic regression analysis. LOR was observed in 54 patients (57.4%). The prevalence of sarcopenia in the LOR group was higher than that in response group (70.4% vs. 40.0%, p = 0.003). Sarcopenia (odds ratio [OR] = 3.89, 95% confidence interval [CI]: 1.31-11.54), Montreal L1 type (OR = 0.20, 95% CI: 0.06-0.60), perianal lesions (OR = 4.08, 95% CI: 1.31-12.70), and monocytes percentage (OR = 1.27, 95% CI: 1.02-1.57) at baseline were independent associated factors for LOR. Sarcopenia was also associated with LOR in patients who received infliximab (OR = 3.31, 95% CI: 1.11-9.87). Montreal L1 type, perianal lesions, and monocytes percentage (Model 1), and with additional consideration of sarcopenia (Model 2), were developed to predict LOR. Model 2 showed better performance than Model 1 (area under the curve [AUC] 0.82 vs. 0.75). Sarcopenia was associated with the LOR to biological agents or infliximab in adult patients with CD.

Identification of Targets for Subsequent Treatment of Crohn's Disease Patients After Failure of Anti-TNF Therapy

Background

Anti-TNF medications are the first-line treatment for Crohn's Disease (CD), despite the fact that a significant portion of the population continues to be ineffectively treated. This research aims to discover accurate intervention targets for the follow-up of anti-TNF non-responders using bioinformatics technology.

Methods

GSE16879, GSE111761, and GSE52746 retrieved from the GEO database. Unbiased differentially expressed genes (DEGs) were discovered utilizing the limma and RobustRankAggreg (RRA) tools. Then, we used weighted gene co-expression network analysis (WGCNA) to identify the module most strongly associated with non responders and subjected this module to Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analysis with overlapping genes of the DEGs. GSEA analysis applied to check the results of GO and KEGG. Using the Cytoscape program, the protein-protein interaction (PPI) network was constructed. The software's MCODE addon and CytoHubba addon was used to find the most important modules and the hub genes. Subsequently, we employed reverse transcription-polymerase chain reaction (RT-PCR) to confirm hub gene expression from mucosal biopsy specimens.

Results

There were a total of 142 genes co-upregulated and 65 genes co-downregulated. According to the WGCNA analysis, 42 genes were duplicated inside the light cyan module. GO and KEGG enrichment analyses of overlapped genes in nonresponders demonstrated an increase in the expression of genes associated with inflammation and immune response, consistent with GSEA results. The PPI network was constructed using 41 protein nodes and 177 edges. After validation, 8 of the top 10 genes were verified to be differentially expressed.

Conclusion

Our investigation is the first to integrate three CD databases after the anti-TNF medication treatment. We identified IL1B, CCL4, CXCL1, CXCL10, CCL3, CSF3, TREM1, and IL1RN as potential therapeutic targets for patients whose anti-TNF treatment failed.

Screening Failure in a Large Clinical Trial Centre for Inflammatory Bowel Diseases: Rates, Causes, and Outcomes

BACKGROUND

Patients with inflammatory bowel diseases (IBD) sometimes require investigational medicinal therapy in a clinical trial. Before enrollment, patients must meet strict eligibility criteria, hampering recruitment rates. We investigated the rates, causes, and outcomes of screening failure (SF) in a tertiary IBD center.

METHODS

We reviewed all IBD patients screened for sponsored multicenter phase 1-3 induction studies with available global SF rates between January 2008 and March 2021. We compared our SF rates with the global SF rates. Causes of SF were categorized into disease activity, hematology, chemistry, microbiology, protocol violation, and withdrawal of consent. Patient outcomes were categorized into rescreening for the same trial, screening for another trial, (re)introduction of commercially available therapy, surgery, or watchful waiting.

RESULTS

During the study period, 642 local screenings were performed as part of 53 studies. We identified an overall SF rate of 17.1%, compared with 39.2% in the global study population (P < .00001). Causes of SF at our center included ineligible disease activity (36.4%), microbiology (25.5%), protocol violation (16.4%), withdrawal of consent (9.1%), chemistry (6.4%) and hematology (6.4%). Thirty SFs could have been avoided by prescreening that was more thorough. After SF, 34 patients were rescreened for the same trial, 17 screened for another trial, 38 initiated approved therapy, 9 were referred for surgery, and 12 did not receive further therapy.

CONCLUSIONS

A significant proportion of IBD patients consenting to clinical trials fail their screening. Main causes of SF are ineligible disease activity and abnormal finding on microbiology. Approximately one-fourth of SFs could have been avoided by prescreening that was more thorough.

Predictors and optimal management of tumor necrosis factor antagonist nonresponse in inflammatory bowel disease: A literature review

Tumor necrosis factor-α (TNF-α) antagonists, the first biologics approved for treating patients with inflammatory bowel disease (IBD), are effective for the induction and maintenance of remission and significantly improving prognosis. However, up to one-third of treated patients show primary nonresponse (PNR) to anti-TNF-α therapies, and 23%-50% of IBD patients experience loss of response (LOR) to these biologics during subsequent treatment. There is still no recognized predictor for evaluating the efficacy of anti-TNF drugs. This review summarizes the existing predictors of PNR and LOR to anti-TNF in IBD patients. Most predictors remain controversial, and only previous surgical history, disease manifestations, drug concentrations, antidrug antibodies, serum albumin, some biologic markers, and some genetic markers may be potentially predictive. In addition, we also discuss the next steps of treatment for patients with PNR or LOR to TNF antagonists. Therapeutic drug monitoring plays an important role in treatment selection. Dose escalation, combination therapy, switching to a different anti-TNF drug, or switching to a biologic with a different mechanism of action can be selected based on the concentration of the drug and/or antidrug antibodies.

Vaccination therapy for inflammatory bowel disease

Recently, several novel medications, such as Ustekinumab, Infliximab, and Vedolizumab, have emerged as potential options for inflammatory bowel disease(IBD) management. Despite achieving some effects in clinical applications, these therapies are still plagued by inadequate response rates and adverse side effects. With rapid progress in immunological research, therapeutic vaccines are gaining traction as an alternative. These vaccines aim to activate the body's immune system to generate specific antibodies, thereby offering a potential avenue for treating IBD. The efficacy and safety of vaccines, coupled with their potential to mitigate the financial and healthcare burden associated with disease treatment, render therapeutic vaccines a more favorable approach for managing patients with IBD. In this review, we critically examine the existing literature pertaining to therapeutic vaccines for IBD, aiming to offer researchers a comprehensive understanding of their applications and prospects and stimulate novel vaccine development by presenting innovative ideas in this field.

Dose Escalation Patterns of Advanced Therapies in Crohn's Disease and Ulcerative Colitis: A Systematic Literature Review

INTRODUCTION

Dose escalation is one of the treatment approaches studied and suggested in advanced therapies for Crohn's disease (CD) and ulcerative colitis (UC). This study aimed to identify and characterize the dosing escalation patterns of advanced therapies in CD and UC.

METHODS

Two systematic literature reviews (SLRs) were conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. MEDLINE®, Embase®, and Cochrane Library were searched for articles published between January 2011 and October 2021 and limited to non-interventional studies in English language. Congress and bibliographic searches were also conducted. Articles were screened by two independent researchers. Dose escalation patterns were described and summarized considering the regional regulatory label recommendation (in North America [NA] or outside of North America [ONA]).

RESULTS

Among 3190 CD and 2116 UC articles identified in the Ovid searches, 100 CD and 54 UC studies were included in the SLR, with more studies conducted ONA. Most studies reported an initial maintenance dose pattern aligned with the lower starting dose per local regulatory label; however, several ONA studies (n = 13 out of 14) reported ustekinumab every 8 weeks as starting maintenance pattern in CD. In ONA studies, the median within-guideline escalation rates in CD and UC were 43% in ustekinumab (CD only), 33% and 32% for vedolizumab; 29% and 39% for adalimumab; and 14% and 10% for infliximab. Evidence regarding dose escalation patterns for tofacitinib, certolizumab pegol, and golimumab was limited. Some dose escalation patterns outside of label recommendations were observed including ustekinumab every 8 weeks to every 4 weeks and vedolizumab every 8 weeks to every 6 weeks.

CONCLUSION

Dose escalation strategies are widely documented in the literature. The reported dose escalation patterns and escalation rates vary by region and by CD and UC. Most escalation patterns reported were aligned with regulatory recommendations while some reported more diverse or aggressive dose escalation.

PROSPERO REGISTRATION

CRD42021289251.

Validation of a rapid HLA-DQA1*05 pharmacogenomics assay to identify at-risk resistance to anti-tumor necrosis factor therapy among patients with inflammatory bowel disease

OBJECTIVES

The HLA-DQA1*05 variant (rs2097432) is associated with increased risk of immunogenicity to tumor necrosis factor antagonists, with subsequent resistance to therapy in patients with inflammatory bowel disease. Identification of these patients would optimize personalized therapeutic selection.

METHODS

Genomic DNA was extracted from 80 deidentified samples in an unselected patient population with an unknown rs2097432 genotype. Split sample analysis was performed using a reference laboratory. Primer probes for a TaqMan quantitative polymerase chain reaction (qPCR) assay (Thermo Fisher Scientific) were custom designed. Synthesized genomic-block fragments were used as controls. All qPCR reactions were performed using a TaqMan GTXpress Master Mix (Thermo Fisher Scientific) on the Applied Biosystems 7500 system under fast cycling conditions.

RESULTS

Of 80 samples, 50% were wild-type reference genotypes, 22.5% were heterozygous, and 27.5% were homozygous variant calls, comparable to population data. Split analysis samples between 2 independent laboratories were 100% concordant. The detection limit tested across genomic-block controls processed in duplicate was reproducible on sample input from 10 ng titrated down to 1.25 ng across 2 independent runs. Further, analytical specificity assessed with previous wild-type reference and homozygous variant DNA spiked into genomic-block controls produced appropriate heterozygous genotypes.

CONCLUSIONS

Here we present validation of a lab-developed test for a rapid HLA-DQA1*05 (rs2097432) pharmacogenomics assay targeting a hotspot identified by genome-wide association studies. Targeted genotyping employed here will allow for expeditious personalized therapeutic selection.

Systematic Review and Meta-Analysis of Observational Studies on the Effectiveness and Safety of Ustekinumab among Patients with Inflammatory Bowel Disease in Eastern and Western Countries

BACKGROUND

Ustekinumab (UST) is an IL12/23 inhibitor utilized for altering inflammatory responses in inflammatory bowel disease (IBD). Clinical trials and case reports suggested that the effectiveness and safety of UST may differ among IBD patients in Eastern and Western countries. However, related data have not been systematically reviewed and analyzed.

METHODS

This systematic review and meta-analysis of the safety and effectiveness of UST in IBD included relevant literature from the Medline and Embase databases. The main outcomes were clinical response, clinical remission, endoscopic response, endoscopic remission, and adverse events in IBD.

RESULTS

We analyzed 49 real-world studies, most of which included patients with biological failure (89.1% CD and 97.1% UC). In UC patients, clinical remission rates were 34% at 12 weeks, 40% at 24 weeks, and 37% at 1 year. In CD patients, clinical remission rates were 46% at 12 weeks, 51% at 24 weeks, and 47% at 1 year. Clinical remission rates of CD patients were 40% at 12 weeks and 44% at 24 weeks in Western countries, versus 63% and 72% in Eastern countries, respectively.

CONCLUSION

UST is an effective drug for IBD with a promising safety profile. Although no RCTs have been performed in Eastern countries, the effectiveness of UST on CD patients is not inferior to that in Western countries based on the existing data.

Pathophysiology of Inflammatory Bowel Disease: Innate Immune System

Inflammatory bowel disease (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), is a heterogeneous state of chronic intestinal inflammation with no exact known cause. Intestinal innate immunity is enacted by neutrophils, monocytes, macrophages, and dendritic cells (DCs), and innate lymphoid cells and NK cells, characterized by their capacity to produce a rapid and nonspecific reaction as a first-line response. Innate immune cells (IIC) defend against pathogens and excessive entry of intestinal microorganisms, while preserving immune tolerance to resident intestinal microbiota. Changes to this equilibrium are linked to intestinal inflammation in the gut and IBD. IICs mediate host defense responses, inflammation, and tissue healing by producing cytokines and chemokines, activating the complement cascade and phagocytosis, or presenting antigens to activate the adaptive immune response. IICs exert important functions that promote or ameliorate the cellular and molecular mechanisms that underlie and sustain IBD. A comprehensive understanding of the mechanisms underlying these clinical manifestations will be important for developing therapies targeting the innate immune system in IBD patients. This review examines the complex roles of and interactions among IICs, and their interactions with other immune and non-immune cells in homeostasis and pathological conditions.

Treatment With Adalimumab 80 mg Every Other Week in Inflammatory Bowel Disease: Results of Treatment Intensification in Clinical Practice

Background

Loss of response to anti-tumor necrosis factor drugs in patients with inflammatory bowel disease (IBD) is frequent and, in case of low drug levels, treatment intensification is recommended. In addition, in cases in which clinical response without attainment of remission (clinical, endoscopic, or radiological), intensification could be justified since higher drug levels are associated with better outcomes. For adalimumab (ADA), the standard intensification regimen is 40 mg every week (ew). Availability of ADA 80 mg prefilled pens has enabled every other week (eow) intensification. We assessed the clinical efficacy of intensification with ADA 80 mg eow.

Methods

This retrospective study was conducted at a tertiary hospital in Spain. Patients with IBD receiving maintenance ADA 80 mg eow with clinical, biomarker, and drug-level assessments were included. Demographics and clinical, biological, and endoscopic evaluation of the disease before and after ADA intensification, and pharmacokinetic assessments, were collected.

Results

Eighty-seven patients (72 Crohn's disease, 15 ulcerative colitis; average age 50 years) were included. Reasons for ADA intensification were: low ADA levels-<5 µg mL^-1-(17%), low ADA levels-<5 µg mL^-1-without clinical response (63%), clinical response without clinical remission (15%) and active disease on objective evaluation (including colonoscopy, magnetic resonance imaging, capsule endoscopy, and/or intestinal ultrasound; 5%). Following treatment intensification to ADA 80 mg eow, 75 patients (86%) were in clinical remission and 69 (79.3%) were in biologic remission (clinical remission and normalization of biomarkers). After a median follow-up of 19 months (interquartile range 13-25), 63 patients (72%) remained on treatment and in clinical remission. There were no serious infections, hospitalizations, or deaths. Drug costs did not increase with the 80 mg eow regimen versus a standard intensification regimen.

Conclusions

ADA intensification to 80 mg eow was safe, effective, and did not increase drug costs versus standard intensification to 40 mg ew in our experience.

Effectiveness and Safety of Tofacitinib for Ulcerative Colitis: Systematic Review and Meta-analysis

BACKGROUND

The objective of our systematic review and meta-analysis was to evaluate the effectiveness and safety of tofacitinib in the treatment of moderate-severe ulcerative colitis (UC).

METHODS

We searched Medline, Embase, Web of Science, and Cochrane Central to identify articles and abstracts reporting efficacy or safety data on tofacitinib use in UC. Primary outcome assessed was remission. Secondary outcomes included clinical response, steroid free remission, and adverse events (AEs).

RESULTS

A total of 26 studies were included. The rates of remission were 29.81% [95% confidence interval (CI): 22.37%-37.25%, I2 : 90%] at week 8, 32.27% (95% CI: 27.67%-36.88%, I2 : 42%) at 6 months and 38.03% (95% CI: 33.59%-42.48%, I2 : 0%) at 1-year. Clinical response rates were 59.41% (95% CI: 55.03%-63.94%, I2 : 61%) at week 8, 48.99% (95% CI: 36.92%-61.06%, I2 : 91%) at 6 months and 50.87% (95% CI: 42.16%-59.58%, I2 : 67%) at 1-year. Odds ratio of clinical response at week 8 in biologic naive versus biologic experienced patients was 1.59 (95% CI: 0.54-4.63). Pooled incidence rate for serious infections, major adverse cardiovascular events, and nonmelanotic squamous cell malignancies across all doses was 4.41 per 100-patient years (PYs) (95% CI: 2.32-8.38 per 100-PY, I2 : 78%), 0.91 per 100-PY (95% CI: 0.43-1.93 per 100-PY, I2 : 37%) and 0.91 per 100-PY (95% CI: 0.61-1.34 per 100-PY, I2 : 0%), respectively. Higher dose was associated with an increased frequency of AEs.

CONCLUSIONS

While the overall efficacy and safety of tofacitinib in moderate-severe UC is consistent with clinical trial data, the dose dependent increase in AEs highlights the significance of early dose de-escalation. Rate of clinical response after tofacitinb induction was similar in biologic naive and biologic experienced patients.

A Systematic Review on the interest of Drug Tolerant assay in the monitoring of Inflammatory Bowel Disease

Many patients with inflammatory bowel disease (IBD) are treated with anti-tumor necrosis factor (TNF) therapies, of which infliximab (IFX) is most commonly used. Loss of response (LOR) to anti-TNF therapy due to immunogenic failure accounts for 20% of subsequent medical intervention and is defined, using a drug sensitive assay, as low or undetectable concentration of drug with high titers of anti-drug antibodies (ADAb). We performed a systematic review to investigate the use of a drug tolerant assay during both induction and maintenance to monitor patients treated with anti-TNFs. After the search on PubMed, 90 publications were reviewed. Most ADAb detection methods are drug sensitive, cannot detect ADAb in the presence of drug, and therefore cannot be used close to drug administration, when the drug concentration is too high. To overcome this major limitation, several drug-tolerant techniques have been developed and will be discussed in this review. Using drug-tolerant assays ADAb against infliximab (IFX) or adalimumab (ADM) can be detected during induction and predict primary non-response or LOR. Drug sensitive assays do not allow detection of ADAb during the induction phase as IFX or ADM concentration is typically high.

Filgotinib for moderately to severely active ulcerative colitis

INTRODUCTION

Filgotinib is an oral Janus kinase type 1 (JAK1) selective inhibitor with demonstrated efficacy and safety in ulcerative colitis (UC). The aim of this review is to summarize the available evidence on pharmacological characteristics, efficacy, and safety of filgotinib in UC.

AREAS COVERED

Pubmed, Scopus, and Embase databases were searched for all relevant studies reporting the efficacy and safety of filgotinib in patients with moderate to severe UC. We particularly focused on the risk of zoster infection and venous thromboembolism compared to other JAK inhibitors.

EXPERT OPINION

Filgotinib has remarkable efficacy, safety, and tolerability profiles in the treatment of moderate-to-severe active UC. It can be used in both biologic-naïve and biologic-experienced patients. The rapid mechanism of action and its oral administration route make it a reliable therapeutic option.

Novel technologies to characterize and engineer the microbiome in inflammatory bowel disease

We present an overview of recent experimental and computational advances in technology used to characterize the microbiome, with a focus on how these developments improve our understanding of inflammatory bowel disease (IBD). Specifically, we present studies that make use of flow cytometry and metabolomics assays to provide a functional characterization of microbial communities. We also describe computational methods for strain-level resolution, temporal series, mycobiome and virome data, co-occurrence networks, and compositional data analysis. In addition, we review novel techniques to therapeutically manipulate the microbiome in IBD. We discuss the benefits and drawbacks of these technologies to increase awareness of specific biases, and to facilitate a more rigorous interpretation of results and their potential clinical application. Finally, we present future lines of research to better characterize the relation between microbial communities and IBD pathogenesis and progression.

Next-Generation Personalized Medicine: Implementation of Variability Patterns for Overcoming Drug Resistance in Chronic Diseases

Chronic diseases are a significant healthcare problem. Partial or complete non-responsiveness to chronic therapies is a significant obstacle to maintaining the long-term effect of drugs in these patients. A high degree of intra- and inter-patient variability defines pharmacodynamics, drug metabolism, and medication response. This variability is associated with partial or complete loss of drug effectiveness. Regular drug dosing schedules do not comply with physiological variability and contribute to resistance to chronic therapies. In this review, we describe a three-phase platform for overcoming drug resistance: introducing irregularity for improving drug response; establishing a deep learning, closed-loop algorithm for generating a personalized pattern of irregularity for overcoming drug resistance; and upscaling the algorithm by implementing quantified personal variability patterns along with other individualized genetic and proteomic-based ways. The closed-loop, dynamic, subject-tailored variability-based machinery can improve the efficacy of existing therapies in patients with chronic diseases.

Comparative Efficacy of Infliximab vs Ustekinumab for Maintenance of Clinical Response in Biologic Naïve Crohn's Disease

BACKGROUND

There is a need to better understand the positioning of biologic therapies for long-term outcomes in biologic-naïve Crohn's disease (CD). We assessed the comparative effectiveness of infliximab and ustekinumab among induction responders for 1-year outcomes.

METHODS

This post hoc analysis included data from 220 biologic-naïve CD participants with response to induction therapy from 2 clinical trial programs. Participants achieving 1-year clinical remission (CR) (Crohn's disease activity index <150), corticosteroid-free CR, normalization of fecal calprotectin (FC), endoscopic response (Simple Endoscopic Score for CD decrease ≥50% from baseline), and endoscopic remission (ER) (Simple Endoscopic Score for CD <3) were compared. Multivariate logistic regression evaluated the likelihood of achieving the outcomes adjusted for confounders. Propensity score matching created a cohort with similar distribution of baseline covariates.

RESULTS

One-year CR and corticosteroid-free CR rates were similar between infliximab-treated and ustekinumab-treated patients (CR, 66 of 110 [60.0%] vs 63 of 110 [57.3%]; adjusted odds ratio [aOR], 1.15; 95% CI, 0.67-1.98; P = .681; corticosteroid-free CR, 11 of 28 (39.3%) vs 27 of 51 [52.9%]; aOR, 0.58; 95% CI, 0.23-1.47; P = .251). Compared with ustekinumab-treated patients, infliximab-treated participants were more likely to achieve 1-year endoscopic response (43 of 92 [46.7%] vs 6 of 30 [20.0%], aOR, 3.59; 95% CI, 1.34-9.66; P = .011) and ER (31 of 92 [33.7%] vs 4 of 30 [13.3%]; aOR, 3.35; 95% CI, 1.07-10.49; P = .038). Among patients with FC ≥250 mg/kg at baseline, normalization (<250 mg/kg) at 1-year was similar between groups. Similar results were observed within the propensity matched population for all analyses.

CONCLUSIONS

Treatment with infliximab and ustekinumab among induction responders achieved 1-year CR with similar efficacy, but infliximab may confer greater benefit for endoscopic outcomes. Findings should be interpreted with caution as our analyses were unpowered.

Serological Biomarkers of Extracellular Matrix Turnover and Neutrophil Activity Are Associated with Long-Term Use of Vedolizumab in Patients with Crohn's Disease

Crohn’s disease (CD) is a relapsing-remitting inflammatory disease of the gastrointestinal (GI) tract characterized by increased extracellular matrix (ECM) remodeling. The introduction of the α4β7-integrin inhibitor vedolizumab (VEDO) has improved disease management, although there is a high rate of primary non-response in patients with CD. We studied whether ECM biomarkers of neutrophil activity and mucosal damage could predict long-term response to VEDO in patients with CD. Serum levels of human neutrophil elastase (HNE)-derived fragments of calprotectin (CPa9-HNE), and matrix metalloproteinase (MMP)-derived fragments of type I (C1M), III (C3M), IV (C4M), and VI (C6Ma3) collagen, type III collagen formation (PRO-C3), basement membrane turnover (PRO-C4) and T-cell activity (C4G), were measured using protein fingerprint assays in patients with CD (n = 32) before VEDO therapy. Long-term response was defined as VEDO treatment of at least 12 months. CPa9-HNE was significantly increased at baseline in non-responders compared with responders (p < 0.05). C1M, C3M, C4M, C6Ma3, and PRO-C4 were also significantly increased at baseline in non-responders compared with responders (all p < 0.05). All biomarkers were associated with response to VEDO (all p < 0.05). To conclude, baseline levels of serum biomarkers for neutrophil activity and mucosal damage are linked to the pathology of CD, and are associated with long-term use of VEDO in patients with CD. Therefore, these biomarkers warrant further validation and could aid in therapeutic decision-making concerning vedolizumab therapy.

Immunogenicity of Monoclonal Antibodies and the Potential Use of HLA Haplotypes to Predict Vulnerable Patients

The use of monoclonal antibodies (mAbs) in the clinic has successfully expanded to treatment of cancer, viral infections, inflammations, and other indications. However, some of the classes of mAbs that are used in the clinic show the formation of anti-drug antibodies (ADAs) leading to loss of efficacy. This review describes ADA formation for the various mAbs, and its clinical effect. Lastly, this review considers the use of HLA-haplotypes as biomarkers to predict vulnerability of patients sensitive to formation of ADAs.

Alterations and Potential Applications of Gut Microbiota in Biological Therapy for Inflammatory Bowel Diseases

Inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis, is a chronic immune-mediated inflammatory disorder of the gastrointestinal tract that is closely associated with dysbiosis of the intestinal microbiota. Currently, biologic agents are the mainstream therapies for IBD. With the increasing incidence of IBD, limitations of biologic agents have gradually emerged during treatment. Recent studies have indicated that gut microbiota is highly correlated with the efficacy of biologic agents. This review focuses on alterations in both the components and metabolites of gut microbiota during biological therapy for IBD, systematically summarises the specific gut microbiota closely related to the clinical efficacy, and compares current predictive models for the efficacy of biologics, further highlighting the predictive value of intestinal microbiota. Based on the mechanistic analysis of faecal microbiota transplantation (FMT) and biologic agents, a new therapeutic strategy, comprising a combination of FMT and biologics, has been proposed as a promising treatment for IBD with improved efficacy.

Visceral Adipose Tissue Volumetrics Inform Odds of Treatment Response and Risk of Subsequent Surgery in IBD Patients Starting Antitumor Necrosis Factor Therapy

BACKGROUND

Data describing the effect of obesity on antitumor necrosis factor (anti-TNF) treatment response are inconsistent. Visceral adipose tissue (VAT) is a superior marker of adiposity to body mass index. However, its effect on treatment response is unclear. We aimed to evaluate the effect of VAT on anti-TNF treatment response.

METHODS

Inflammatory bowel disease (IBD) patients starting anti-TNF agents between January 1, 2009, and July 31, 2019, were included. 3-dimensional measurements of VAT volume and visceral fat index (visceral:subcutaneous adipose tissue ratio; VFI) were obtained from computed tomography (CT) scans. Subjects were categorized by predefined volume cutoffs (<1500cm3, 1500-2999cm3, ≥3000cm3) and VFI (<0.33, 0.33-0.66, ≥0.67). Primary outcomes included a composite treatment response end point at 6 and 12 months. Secondary outcomes were surgery at 6 and 12 months. Multivariable logistic regression was used to calculate adjusted odds ratio (aOR) and 95% confidence interval (CI).

RESULTS

The final cohort included 176 patients. No significant differences in treatment response at 6 months was observed. At 12 months, compared with volume <1500cm3, patients with volume 1500-2999cm3 had higher odds of response (aOR, 3.52; 95% CI, 1.16-10.71; P = .023), whereas volume ≥3000cm3 did not. Compared with VFI<0.33, VFI ≥0.67 had higher odds of surgery at 6 (aOR, 48.22; 95% CI, 4.73-491.57; P = .023) and 12 months (aOR, 20.94; 95% CI, 3.14-139.67; P = .004). Post hoc analysis suggested VAT may affect drug pharmacokinetics.

CONCLUSIONS

We found VAT volume is associated with anti-TNF treatment response in a nondose dependent manner, and VFI may inform risk of surgery after anti-TNF initiation. If confirmed by prospective studies, VAT volumetrics are potentially useful biomarkers to inform IBD treatment decisions.

Dual biologic therapy with Vedolizumab and Ustekinumab for refractory Crohn's disease in children

There is a paucity of treatment options for patients who have failed multiple biologics. A drawback of biologic therapies is their selectivity in targeting a single pathway. We report the use of dual biologic therapy with vedolizumab and ustekinumab for three highly refractory patients who previously failed both of these medications as monotherapy. The dual biologic therapy led to the closure of a recto-vaginal fistula and restoration of continuity after takedown of a stoma.

Therapeutic drug monitoring in dermatology: the way towards dose optimization of secukinumab in chronic plaque psoriasis

Background

Despite the favourable efficacy profile of secukinumab, clinicians encounter varying clinical responses among patients potentially associated with under‐ and overdosing. As biologics are expensive, their rational use is crucial and evident. Therapeutic drug monitoring could guide clinicians in making decisions about treatment modifications.

Aim

In this multicentre, prospective study, we aimed to develop and validate a secukinumab immunoassay and searched for the therapeutic window in patients with psoriasis.

Methods

We determined secukinumab concentrations at trough in sera from 78 patients with psoriasis at multiple timepoints (Weeks 12, 24, 36, 48 and 52; after Week 52, measurements could be taken at an additional three timepoints) during maintenance phase, using an in‐house secukinumab immunoassay consisting of a combination of MA‐SEC66A2 as capture antibody and MA‐SEC67A9, conjugated to horseradish peroxidase, as detecting antibody. At each hospital visit, disease severity was assessed using the Psoriasis Area and Severity Index (PASI).

Results

After quantification, 121 serum samples were included for dose–response analysis. Based on a linear mixed‐effects model, secukinumab trough concentrations were found to decrease with increasing body mass index (BMI). Based on receiver operating characteristic (ROC) analysis, we concluded that the minimal effective secukinumab threshold was 39.1 mg/L in steady state, and that this was associated with a 92.7% probability of having an optimal clinical response (PASI ≤ 2 or reduction in PASI of ≥ 90%).

Conclusions

Monitoring and targeting a secukinumab trough concentration of 39.1 mg/L may be a viable treatment option in suboptimal responders. In patients with higher BMI, weight‐based dosing may be needed in order to prevent underdosing.

Systematic review and meta-analysis: evaluating response to empiric anti-TNF dose intensification for secondary loss of response in Crohn's disease

INTRODUCTION

Anti-tumor necrosis factor (TNF) dose intensification represents an effective method of overcoming secondary loss of response (LOR); however, a subset of patients may not respond (tertiary non-response), or fail to demonstrate durable response (tertiary LOR) to intensified dosing. This systematic review and meta-analysis aimed to evaluate these outcomes to determine the clinical effectiveness of empiric dose intensification in Crohn's disease.

METHODS

Multiple databases including MEDLINE and EMBASE were interrogated to identify studies that reported outcomes following anti-TNF dose intensification to address secondary LOR in Crohn's disease. Studies that used anti-TNF levels as the primary basis for dose intensification were excluded. Studies that reported (1) tertiary response and tertiary non-response within 6 months or (2) tertiary response and tertiary LOR beyond 6 months, were pooled using a random effects model with risk ratio (RR) derived, quantifying the effect of each comparison.

RESULTS

Twenty-six studies reported outcomes following anti-TNF dose intensification to address secondary LOR. Short-term response within 12 weeks of any dose-intensification strategy was 33-90%, while sustained response (⩾48 weeks) was achieved in 25-85%. Tertiary non-response occurred in up to 45% of intensified patients within 6 months of anti-TNF dose intensification, while tertiary LOR beyond 6 months occurred in up to 64% of patients. Tertiary response was more likely than tertiary non-response within 6 months (RR 2.58, 95% CI (1.76, 3.79), I ² = 82%, 12 studies), while sustained response beyond 6 months compared to tertiary LOR (RR 1.10 (0.75, 1.61) I ² = 85%, 7 studies) was less convincing.

CONCLUSION

Although anti-TNF dose intensification is clinically effective in patients with Crohn's disease, particularly within the first 6 months, a proportion of patients will fail to demonstrate short-term and/or sustained clinical response. Hence, clinical reassessment following anti-TNF dose intensification, particularly beyond 6 months, remains important to differentiate between effective and ineffective dose-intensification strategies.

Rupatadine ameliorated ulcerative colitis in rats via modulation of platelet-activatiweng factor/interleukin-6/vascular endothelial growth factor signalling pathway

OBJECTIVES

This study aimed to analyse the potential effect of rupatadine (RUP) on ulcerative colitis (UC) induced by acetic acid (AA).

METHODS

Forty male adult Wistar rats were divided into five groups: Control group: received vehicles for 14 days; AA model group: received AA at the 13th day; Sulfasalazine (SLZ) + AA group: received SLZ (250 mg/kg) for 14 days and AA at the 13th day; RUP-3 + AA group: received RUP (3 mg/kg/day) for 14 days and AA at the 13th day; and RUP-6 + AA group: received RUP (6 mg/kg/day) for 14 days and AA at the 13th day. Evidence of UC was assessed both macroscopically and microscopically. Oxidative stress markers (total antioxidant capacity and malondialdehyde), antioxidant enzyme (superoxide dismutase), histamine and platelet-activating factor (PAF) were determined. Immunohistochemical estimations of vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) were done.

KEY FINDINGS

The AA group showed evidence of UC that was associated with a significant increase in oxidative stress, histamine and PAF levels with significant elevation in colonic VEGF and IL-6 immuno-expressions. RUP, in a dose-dependent manner, significantly ameliorated UC.

CONCLUSION

RUP protects against UC by reducing oxidative stress and by regulating the PAF/IL-6/VEGF pathway.

Modulation of Gut Barrier Functions in Ulcerative Colitis by Hyaluronic Acid System

The active stages of intestinal inflammation and the pathogenesis of ulcerative colitis are associated with superficial mucosal damage and intermittent wounding that leads to epithelial barrier defects and increased permeability. The standard therapeutic interventions for colitis have focused mainly on maintaining the remission levels of the disease. Nonetheless, such treatment strategies (using anti-inflammatory, immunomodulatory agents) do not address colitis' root cause, especially the mucosal damage and dysregulated intestinal barrier functions. Restoration of barrier functionality by mucosal healing or physical barrier protecting strategies shall be considered as an initial event in the disease suppression and progression. Herein, a biphasic hyaluronan (HA) enema suspension, naïve-HA systems that protect the dysregulated gut epithelium by decreasing the inflammation, permeability, and helping in maintaining the epithelial barrier integrity in the dextran sodium sulfate-induced colitis mice model is reported. Furthermore, HA-based system modulates intestinal epithelial junctional proteins and regulatory signaling pathways, resulting in attenuation of inflammation and mucosal protection. The results suggest that HA-based system can be delivered as an enema to act as a barrier protecting system for managing distal colonic inflammatory diseases, including colitis.

High oncostatin M predicts lack of clinical remission for patients with inflammatory bowel disease on tumor necrosis factor α antagonists

The interleukin-6 family cytokine, oncostatin-M (OSM) has been associated with response to tumor necrosis factor-α antagonists (anti-TNFs) in small cohorts of patients with inflammatory bowel disease (IBD). We aimed to evaluate the association between plasma OSM concentrations and response to anti-TNFs (infliximab and adalimumab) in both ulcerative colitis (UC) and Crohn’s disease (CD). A retrospective cohort study was conducted in patients with IBD with a history of anti-TNF exposure. Blood samples, collected prior to anti-TNF exposure, were analyzed by enzyme-linked immunosorbent assay for the presence and quantity of OSM. Clinical remission was assessed at 1-year post anti-TNF exposure in addition to the occurrence of surgery, hospitalization, corticosteroid use, and adverse drug events. Lastly the threshold OSM plasma concentration associated with anti-TNF non-response was assessed by receiver operator characteristic (ROC) curve analysis. Patients with IBD (CD, n = 82; UC, n = 40) were assessed. In both UC and CD, mean pre-treatment OSM concentrations were significantly lower in those who achieved clinical remission at 1-year (p < 0.0001). A threshold plasma OSM concentration of 168.7 pg/ml and 233.6 pg/ml respectively separated those who achieved clinical remission at 1-year on an anti-TNF from those who did not in CD and UC respectively (CD: area under the receiver operator characteristic curve, AUROC = 0.880, 95% CI 0.79–0.96; UC: AUROC = 0.938, 95% CI 0.87–1.00). High OSM concentrations were associated with anti-TNF discontinuation and use of rescue steroids in CD and UC. High pre-treatment OSM concentrations identify IBD patients at-risk of anti-TNF non-response at 1-year as well as other deleterious clinical outcomes.

Increased SERPINA3 Level Is Associated with Ulcerative Colitis

Ulcerative colitis (UC) is a recurrent, chronic intestinal disease that is currently incurable. Its pathogenesis remains to be further understood. Therefore, seeking new biomarkers and potential drug targets is urgent for the effective treatment of UC. In this study, the gene expression profile GSE38713 was obtained from the GEO (Gene Expression Omnibus) database. Data normalisation and screening of the differentially expressed genes (DEGs) were conducted using R software, and gene ontology (GO) enrichment was performed using Metascape online tools. The PubMed database was used to screen new genes that have not been reported, and SERPINA3 was selected. The correlation between SERPINA3 and other inflammatory factors was analysed by Spearman correlation analysis. Finally, colitis model mice and an in-vitro model were established to validate the function of the SERPINA3 gene. SERPINA3 gene expression was markedly increased in UC patient samples, colitis models and in-vitro models and showed an association with other inflammatory factors. ROC analysis indicated that SERPINA3 could represent a potential biomarker of active UC. Additionally, silencing SERPINA3 in an in-vitro intestinal epithelial inflammatory model significantly decreased the mRNA level of inflammatory factors. This study provides supportive evidence that SERPINA3 may act as a key biomarker and potential drug target in UC treatment.

Levels of Biosimilar Infliximab during and after Induction Treatment in Crohn's Disease and Ulcerative Colitis-A Prospective Polish Population Study

Background: Primary lack or secondary loss of response to therapy with infliximab is a significant problem. This study aimed to evaluate the response to treatment in patients with Crohn’s disease (CD) and ulcerative colitis (UC) achieving therapeutic and sub-therapeutic trough levels of biosimilar infliximab (CT-P13). Results: A total of 65 patients (32 with CD and 33 with UC) were recruited. The overall response rate in both CD and UC patients exceeded 80%. There were no significant differences in treatment response and CT-P13 levels for patients with CD or UC. We did not find significant differences in the percentage of patients achieving drug levels of 3 μg/mL at week 6, 10, or 12; a significant decrease was observed at week 14. Up to 55.5% of patients with CD and 64.3% of patients with UC with sub-therapeutic CT-P13 levels at week 14 primarily responded to treatment. Conclusions: Intermediate measurements of drug levels at weeks 10 and 12 did not capture any pronounced decrease in infliximab concentrations below therapeutic levels in either group, thus suggesting no clinical usefulness. A significant percentage of patients primarily responded to treatment despite sub-therapeutic drug levels after the induction phase.

Potential application of measuring serum infliximab levels in rheumatoid arthritis management: A retrospective study based on KURAMA cohort data

Infliximab (IFX) therapy has considerably improved the treatment of rheumatoid arthritis (RA). However, some patients still do not respond adequately to IFX therapy, or the efficacy of the treatment diminishes over time. Although previous studies have reported a relationship between serum IFX levels and therapeutic efficacy, the potential applications of IFX therapeutic drug monitoring (TDM) in clinical practice remain unclear. The purpose of this study was to investigate the potential applications of IFX TDM by analyzing a Japanese cohort database. Data were collected retrospectively from the Kyoto University Rheumatoid Arthritis Management Alliance cohort between January 1, 2011, and December 31, 2018. Serum IFX levels were measured using a liquid chromatography-tandem mass spectrometer. Out of the 311 RA patients that used IFX, 41 were eligible for the analysis. Serum IFX levels were significantly higher in responders than in non-responders. An optimal cut-off value was determined to be 0.32 μg/mL based on a receiver operating characteristic curve. At the IFX measurement point, a better therapeutic response was observed in the high IFX group (n = 32) than in the low IFX group (n = 9). Conversely, at the maximum effect point, when DAS28-ESR was the lowest between IFX introduction and measurement points, there were no differences in responder proportions between the low and high IFX groups. IFX primary ineffectiveness could be avoided with appropriate dose escalation without blood concentration measurement in clinical practice. In conclusion, IFX TDM could facilitate the identification of secondary non-responders and in turn, proper IFX use.

Post-Induction High Adalimumab Drug Levels Predict Biological Remission at Week 24 in Patients With Crohn's Disease

INTRODUCTION

We investigated whether early adalimumab drug levels (ADL) at week 4 predicted biological remission at week 24.

METHODS

In a prospective study, we assessed clinical and biological remission at weeks 0, 4, 12, and 24 after induction of adalimumab in 33 patients with Crohn's disease. Disease activity was determined by the Harvey-Bradshaw Index, ileocolonoscopy reports, cross-sectional imaging, C-reactive protein (CRP), and fecal calprotectin (FC) levels. Clinical remission was defined as Harvey-Bradshaw Index <5. Biological remission was defined as a combination of FC < 200 μg/g and CRP <5 μg/mL. ADL trough levels were tested using a liquid phase, mobility shift assay.

RESULTS

At 24 weeks, 18/33 (55%) of the patients were with biological remission. Ten (30%) patients required dose escalation or withdrawal from adalimumab by week 24 because of lack of response and exhibited significantly higher FC (P = 0.003) and CRP (P = 0.002). ADL levels at week 4 (19.8 μg/mL vs 10.2 μg/mL, P = 0.001) were significantly higher in patients with biological remission vs nonresponders at week 24. ADL levels at week 4 were a good predictor of biological remission at week 24, with area under the curve 0.86, 95% confidence interval (1.1; 1.67) and for combined biological and clinical remission, with area under the curve 0.8. The best ADL cutoff at week 4 that predicted biological remission at week 24 was 13.9 μg/mL (sensitivity 94.4% and specificity 73.3%).

DISCUSSION

In individuals with Crohn's disease, higher adalimumab drug levels at week 4 (>13.9 μg/mL) were significantly associated with biological remission at week 24.

Development and Characterisation of Antibody-Based Optical Imaging Probes for Inflammatory Bowel Disease

Monoclonal antibodies are an important addition to the medicinal treatment paradigm for IBD patients. While effective, these agents show a high degree of primary and secondary non-response, and methods to predict response are highly desired. Information on drug distribution at the target level is often lacking. Fluorescent endoscopic imaging using labelled antibody drugs may provide insight regarding drug distribution, target engagement and drug response, but these assessments require stable and functional fluorescently-conjugated probes. Infliximab, vedolizumab, adalimumab and ustekinumab were conjugated to IRDye 800CW, IRDye 680LT and ZW800-1. The resulting 12 tracer candidates were analysed and characterised on SE-HPLC, SDS-PAGE, iso-electric focussing (IEF) and ELISA in order to evaluate their feasibility as candidate clinical tracers for cGMP development. Major differences in the conjugation results could be seen for each conjugated drug. For Infliximab, 2 conjugates (800CW and 680LT) showed formation of aggregates, while conjugates of all drugs with ZW800-1 showed reduced fluorescent brightness, reduced purification yield and formation of fragments. All 6 of these candidates were considered unfeasible. From the remaining 6, ustekinumab-680LT showed reduced binding to IL23, and was therefore considered unfeasible. Out of 12 potential tracer candidates, 5 were considered feasible for further development: vedolizumab-800CW, vedolizumab-680LT, adalimumab-800CW, adalimumab-680LT and ustekinumab-800CW. Infliximab-680LT and ustekinumab-680LT failed to meet the standards for this panel, but may be rendered feasible if tracer production methods were further optimized.

Naringin Exerts Therapeutic Effects on Mice Colitis: A Study Based on Transcriptomics Combined With Functional Experiments

Naringin has been shown to exert protective effects in an animal model of ulcerative colitis, but detailed mechanisms remain unclear. This study aimed to investigate function and signaling mechanisms underlying naringin-induced therapeutic effects on colitis. Two mouse models were established to mimic human Inflammatory bowel disease (IBD) by treating drinking water with dextran sodium sulphate or intra-colonic administration of 2, 4, 6-trinitrobenzene sulfonic acid. Transcriptomics combined with functional experiments were used to investigate underlying mechanisms. Colitis symptoms, including weight loss and high disease activity index were significantly reversed by naringin. The inflammatory response, oxidative reactions, and epithelial cell apoptosis that occur with colitis were also alleviated by naringin. After naringin treatment, transcriptomics results identified 753 differentially expressed mRNAs that were enriched in signaling pathways, including the neuroactive ligand-receptor interaction, calcium signaling, and peroxisome proliferator-activated receptor (PPAR) signaling. The naringin-induced alleviation of colitis was significantly inhibited by the PPAR-γ inhibitor BADGE. In IEC-6 and RAW264.7 cells incubated with lipopolysaccharide (LPS), NF-κB-p65, a downstream protein of PPAR-γ, was significantly increased. Naringin suppressed LPS-induced high expression of NF-κB-p65, which was inhibited by small interfering RNA targeting PPAR-γ. Our study clarifies detailed mechanisms underlying naringin-induced therapeutic effects on mice colitis, and PPAR-γ was found to be the main target of naringin by functional experiments both in vivo and in vitro. Our study supplies new scientific information for the use of naringin in colitis treatment.

Treatment of inflammatory bowel diseases: focusing on biologic agents and new therapies

Background: The treatment of inflammatory bowel diseases has evolved with the development of anti-tumor necrosis factor agents. Despite the long-term effectiveness, many patients experience primary non-response, secondary loss of response, or intolerance. Therefore, the development of new drugs that act on different inflammatory pathways has become necessary. This review focuses on biologic agents and new therapies for the treatment of inflammatory bowel diseases.Current Concepts: Vedolizumab, a gut-selective agent that targets α4β7 integrin is effective in both ulcerative colitis and Crohn’s disease. Ustekinumab is a monoclonal antibody that binds to p40 subunit of interleukin-12/interleukin-23. Ustekinumab is available for the treatment of Crohn’s disease and ulcerative colitis. Tofacitinib is the first Janus kinase inhibitor approved for the treatment of ulcerative colitis. The advantage of tofacitinib is an oral prescription medicine and has rapid action.Discussion and Conclusion: Since vedolizumab, ustekinumab and tofacitinib are effective agents for the treatment of inflammatory bowel diseases, positioning of old and new biologic agents and small molecules should be determined. The safety and efficacy of novel and emerging drugs needs to be evaluated in patients with inflammatory bowel disease.

The Role of Fecal Microbiota Transplantation in the Treatment of Inflammatory Bowel Disease

The exact pathogenesis of inflammatory bowel disease (IBD) is still not completely understood. It is hypothesized that a genetic predisposition leads to an exaggerated immune response to an environmental trigger, leading to uncontrolled inflammation. As there is no known causative treatment, current management strategies for inflammatory bowel disease focus on correcting the excessive immune response to environmental (including microbial) triggers. In recent years, there has been growing interest in new avenues of treatment, including targeting the microbial environment itself. Fecal microbiota transplantation (FMT) is a novel treatment modality showing promising results in early studies. The article discusses the rationale for the use of FMT in inflammatory bowel disease and the yet-unresolved questions surrounding its optimal use in practice.

An Integrated Analysis of Dostarlimab Immunogenicity

Monoclonal antibodies that block the interaction between programmed cell death 1 (PD-1) and its ligand (PD-L1) have revolutionized cancer immunotherapy. However, immunogenic responses to these new therapies—such as the development of antidrug antibodies (ADAs) and neutralizing antibodies (NAbs)—may represent a significant challenge to both efficacy and safety in some patients. Dostarlimab (TSR-042) is an approved, humanized, anti-PD-1 monoclonal antibody that has shown efficacy in multiple solid tumor types. Here, we report the results of an immunogenicity analysis of dostarlimab monotherapy in patients enrolled in the GARNET trial, a multicenter, open-label, single-arm phase 1 study. Overall, 477 of 478 patients (99.8%) were included in the analysis of dostarlimab antibody prevalence, and 349 out of 478 enrolled patients (73.0%) were evaluable for treatment-emergent antibodies to dostarlimab. The incidence of treatment-emergent ADAs was 2.5% at the recommended therapeutic dose (500 mg Q3W for the first 4 doses, 1000 mg Q6W until discontinuation), which is comparable to other anti-PD-(L)1 drugs. NAbs were detected in only 1.3% of patients. In the small percentage of patients who developed ADAs, there was no evidence of altered efficacy or safety of dostarlimab at the recommended dosing regimen. These findings demonstrated that treatment with dostarlimab was associated with a low risk of eliciting clinically meaningful ADAs over the course of this study, and dostarlimab is already approved by health authorities.

Therapeutic drug monitoring in inflammatory bowel disease reduces unnecessary use of infliximab with substantial associated cost-savings

BACKGROUND

Therapeutic drug monitoring (TDM) of infliximab (IFX) levels in inflammatory bowel disease (IBD) patients can help to guide dose adjustments or changes to therapy for selected patients in remission or with secondary loss of response (LOR).

AIMS

To determine how IFX TDM is utilised in a real-life clinical setting and to quantify the potential for TDM to reduce the unnecessary use of IFX.

METHODS

Data from all public IBD IFX level testing performed across Australia were prospectively collected from June 2016 to July 2017 to assess physician-reported for testing indications (induction, in remission or LOR) and associated results. The hypothetical influence of IFX TDM was based on an optimal therapeutic range of 6-10 mg/L for mucosal healing.

RESULTS

Secondary LOR (reactive TDM) was the most common indication for TDM. These patients have consistently lower median IFX levels: 3.02 mg/L (IQR 1.14-6.67 mg/L) versus 5.22 mg/L (IQR 2.70-8.12 mg/L), P = 0.0001 compared with patients in remission (proactive TDM). TDM helped to identify unnecessary use of IFX in 30.6% of the TDM tests performed in luminal Crohn disease and ulcerative colitis patients, with an associated drug cost saving of $531.38 per IFX TDM test episode. Unnecessary IFX use was identified in 38.9% (96/247) of reactive IFX TDM tests performed and in 19.3% (35/181) of proactive testing.

CONCLUSION

Use of both reactive and proactive IFX TDM is cost-effective for IBD management as it informs the clinician where unnecessary use of IFX can be stopped.