Review article: dose optimisation of infliximab for acute severe ulcerative colitis

Editorial: Sequencing rescue therapy for acute severe ulcerative colitis-Ready for revision?

This article is linked to García et al papers. To view these articles, visit https://doi.org/10.1111/apt.17938 and https://doi.org/10.1111/apt.17993

Prevalence and risk factors for early medical and surgical complications following an admission for acute severe ulcerative colitis

Background

Risk factors for colectomy following an episode of acute severe ulcerative colitis (ASUC) have been well studied, but data examining the early complications following an episode is limited.

Objectives

We aimed to evaluate the prevalence and risk factors for medical and surgical complications within 90 days of an ASUC admission and determine if a high-intensity induction infliximab dose is associated with these complications.

Design

Retrospective analysis.

Methods

We conducted a retrospective study of ASUC admissions between January 2015 and July 2021 at a tertiary hospital. The primary outcome was the prevalence of total, medical and surgical complications within 90 days following an ASUC admission. Multivariate linear regression analysis assessed for factors associated with the prevalence of complications.

Results

A total of 150 patients had 186 hospital admissions for ASUC. In total, 101/186 (54.3%) admissions required rescue medical therapy. Standard infliximab induction occurred in 65/100 admissions, accelerated infliximab induction in 35/100 and cyclosporine in 1/100 of admissions. In total, 117 complications, including 74/117 (63.2%) medical and 43/117 (36.8%) surgical complications, arose. Low serum albumin was independently associated with a higher incidence of total [β = -0.08 (95% confidence interval (CI): -0.15, -0.01), p = 0.03] and surgical complications [β = -0.1 (95% CI: -0.18, -0.001), p = 0.047], while an increased age was associated with increased incidence of surgical complications [β = 0.06 (95% CI: 0.01, 0.12), p = 0.02]. A higher Charlson score was associated with increased medical complications [β = 0.12 (95% CI: 0.01, 0.24), p = 0.03]. Infliximab induction dose intensity was not associated with an increased incidence of any complications.

Conclusion

Early complications following an ASUC admission is prevalent although the majority are not serious. Risk factors associated with complications include low serum albumin, older age and a higher comorbidity score. Induction infliximab dose intensity, however, is not a risk factor.

Have changing practices in salvage medical options affected colectomy rates in acute severe ulcerative colitis?

BACKGROUND

In 2014, infliximab (IFX) was listed on the Australian Pharmaceutical Benefits Scheme for acute severe ulcerative colitis (ASUC) and is now the preferred option for medical salvage, superseding cyclosporin A (CsA). Optimal dosing schedules for IFX remain unknown.

AIM

The authors aim to evaluate the effect of changing from predominantly CsA to almost exclusively IFX for the treatment of steroid-refractory ASUC on colectomy rates.

METHODS

A retrospective review was performed of patients admitted with ASUC between 2012 and 2020. Patients were categorised into two groups according to year of presentation - either 'historical treatment' cohort (2012-2014), when CsA was primarily used, or 'contemporary treatment' cohort (2014-2020), when IFX was mostly prescribed, in either standard or intensive doses.

RESULTS

One hundred thirty-nine patients were included; 37 in the historical treatment cohort and 102 in the contemporary treatment cohort. In the historical treatment cohort, 12 of 37 received salvage therapy and eight (67%) received CsA. In the contemporary treatment cohort, 49 of 102 patients received salvage therapy, 40 (82%) with IFX, of whom 22 (53%) received intensified doses. Colectomy rates were similar at 30 days, 6 months and 12 months between historical and contemporary treatment cohorts (14% vs 12% [P = 0.77], 19% vs 18% [P > 0.99],and 22% vs 18% [P = 0.63], respectively). Difference in 12-month colectomy rates between standard versus intensive IFX did not meet statistical significance (three of 21 [14%] vs nine of 22 [41%]. respectively; P = 0.09).

CONCLUSION

There was no difference in 30-day, 6-month or 12-month colectomy rates between the historical treatment and contemporary treatment cohorts. The use of IFX, rather than CsA, even at intensified dosing, does not appear to reduce the colectomy rate observed in our patients.

Infliximab Induction Strategies in Corticosteroid-Refractory Acute Severe Ulcerative Colitis: A Case Series and Literature Review

Acute severe ulcerative colitis (ASUC) is an emergent medical condition and particularly challenging to treat efficaciously. Infliximab is one of the medical salvage treatment options after corticosteroid refractoriness, but the best induction strategy is not yet defined. With this case series, the authors intend to describe three corticosteroid-refractory ASUC cases with different intensified/accelerated infliximab induction approaches and review the literature on this topic. The first case describes an 18-year-old girl with ASUC at disease onset with rapid progression to toxic megacolon, complicated also with anemia, hypoalbuminemia, and coagulopathy. After corticosteroid failure, both accelerated and intensified (10 mg/kg) infliximab regimen was completed within 11 days, with solid clinical response and colon imaging normalization. Second, we present a 26-year-old male with left-sided ulcerative colitis known for 2 years, under mesalazine, who developed a moderate flare and was started on infliximab after partial and inconsistent response to corticosteroids. During the induction period, he presented this time an ASUC episode, which motivated an early and intensified third dose with good clinical response. Finally, we describe the case of a 78-year-old man with ulcerative proctitis for 12 years presenting ASUC with proximal disease extension as well. After unsatisfactory response to corticosteroids, infliximab was initiated on an accelerated induction regimen, completed in 13 days, with the standard dose, achieving clinical remission. Accelerated or intensified infliximab induction plans are becoming current clinical practice in corticosteroid-refractory ASUC. Current guidelines refer to the possibility of this type of strategies, not determining the optimal regimen due to lack of solid evidence. Literature is mainly based on retrospective studies, not randomized, with heterogeneous groups according to disease severity, and the effect on colectomy rates, mainly on the long term, is not clear. Additional well-supported studies are needed on this subject in order to seek a more widely uniform approach.

Severe and refractory gastrointestinal toxicity due to immune checkpoint inhibitors: clinical experience in a tertiary referral hospital

INTRODUCTION

immune checkpoint inhibitors (ICI) are increasingly used to treat several types of cancer. These drugs lead to a wide range of toxicities. Immune-related gastrointestinal adverse events are common and potentially severe. In this manuscript, we recount the real clinical experience in a tertiary center.

METHODS

a retrospective and observational study was conducted in adult patients under ICI treatment. Included patients had been referred to the Gastrointestinal Service of Hospital Universitario Vall d'Hebron for evaluation of severe toxicities, from January 2017 to January 2020, for whom the clinical, epidemiological and evolutive data were collected.

RESULTS

a total of 18 patients were included. Fifty-five percent received anti-programmed cell death protein 1 (PD-1)/anti-programmed death-ligand 1 (anti PD-L1), 11 % received anti-cytotoxic T lymphocyte antigen 4 (CTLA-4) and 33 % received both treatments. The toxicities were manifested as enterocolitis, microscopic colitis and gastritis. Upper gastrointestinal endoscopy was performed in seven patients; all were proved to have histological changes on duodenum biopsies. Treatment was stopped in all patients and steroids were initiated. Sixty-six per cent achieved clinical remission with steroids. Five patients received anti-TNF treatment (infliximab). Only one of the five had responded. Two anti-TNF refractory patients received ustekinumab, with an appropriate clinical response. One patient received apheresis granulocyte as concomitant treatment. A patient with a steroid-dependent course started vedolizumab. Three patients had other immune-related adverse events.

CONCLUSION

gastrointestinal immune-related adverse events are acquiring a higher profile in daily practice and gastroenterologists play an even greater role in the management of these patients.

Therapeutic Drug Monitoring of Infliximab in Acute Severe Ulcerative Colitis

Therapeutic drug monitoring (TDM) is a useful strategy in ulcerative colitis (UC). Nearly a quarter of UC patients will experience acute severe UC (ASUC) in their lifetime, including 30% who will fail first-line corticosteroid therapy. Steroid-refractory ASUC patients require salvage therapy with infliximab, cyclosporine, or colectomy. Fewer data are available for the use of TDM of infliximab in ASUC. The pharmacokinetics of ASUC make TDM in this population more complex. High inflammatory burden is associated with increased infliximab clearance, which is associated with lower infliximab drug concentrations. Observational data support the association between increased serum infliximab concentrations, lower clearance, and favorable clinical and endoscopic outcomes, as well as decreased rates of colectomy. Data regarding the benefit of accelerated or intensified dosing strategies of infliximab-as well as target drug concentration thresholds-in ASUC patients remain more equivocal, though limited by their observational nature. Studies are underway to further evaluate optimal dosing and TDM targets in this population. This review examines the evidence for TDM in patients with ASUC, with a focus on infliximab.

Recent Advances in the Optimization of Anti-TNF Treatment in Patients with Inflammatory Bowel Disease

Despite the evolution in inflammatory bowel disease (IBD) management during the last 20 years owing to the advent of new advanced therapies, anti-TNF agents still remain the cornerstone of therapy for both Crohn's disease and ulcerative colitis. However, this does not only secure favorable outcomes for patients considering the progressive disease character and the high likelihood of primary or secondary loss of response. Therefore, trying to reach a better treatment approach and maximize the benefits anti-TNF agents offer, optimization strategies should be examined. It has been indicated that optimizing treatment with anti-TNF enhances drug efficacy and has been associated with improved disease outcomes and a complication-free disease course. From this perspective, we aim to provide an overview of currently available data and recent advances in the practices of anti-TNF treatment optimization. Special focus has been given to the role of therapeutic drug monitoring (TDM), as well as the utility of combining anti-TNF with an immunomodulator and the treat-to-target approach.

Decreased Infliximab Concentrations in Patients With Inflammatory Bowel Disease Who Carry a Variable Number Tandem Repeat Polymorphism in the Neonatal Fc Receptor or Variant HLADQA1*05G>A Genotype

BACKGROUND

Multiple variables contribute to variation in patient exposure and response to tumor necrosis factor alpha antagonist biologics such as infliximab. This study aimed to assess the association between maintenance-phase infliximab concentrations and genetic variation in HLADQA1*05G>A and fragment crystallisable (Fc) fragment of IgG receptor and transporter (FCGRT) among patients with inflammatory bowel disease.

METHODS

A cross-sectional study was carried out in participants with inflammatory bowel disease prescribed infliximab who were in the maintenance phase of treatment. Participants were genotyped for the presence of the FCGRT variable number tandem repeat (VNTR) and HLADQA1*05G>A (rs74291249). A point estimate of the infliximab trough concentration during the maintenance phase was determined using a standard enzyme-linked immunosorbent assay for each patient. Other variables associated with infliximab pharmacokinetics were collected.

RESULTS

A total of 156 participants with inflammatory bowel disease were included from 2 tertiary care centers affiliated with Western University, London, Canada. Median infliximab trough concentrations were lower in participants who carried the FCGRT VNTR 2/3 or 2/2 (4.14 µg/mL; interquartile range [IQR], 6.48 µg/mL) vs wild type individuals (7.00 µg/mL; IQR, 7.66; P = .0027). Median infliximab trough concentrations were significantly lower in participants who were HLADQA1*05G>A variant carriers (4.73µg/mL; IQR, 4.79) vs wild type individuals (7.85µg/mL; IQR, 7.44; P = .0006). A significant decrease in infliximab trough concentrations was seen in individuals who were dual carriers of variant polymorphisms in HLADQA1*05G>A and FCGRT VNTR (no variants, 8.96µg/mL; IQR, 6.84 vs one variant, 4.96 µg/mL; IQR, 4.95 vs dual variants, 0.86µg/mL; IQR, 5.82).

CONCLUSION

FCGRT VNTR and HLADQA1*05G>A are associated with lower maintenance-phase infliximab concentrations, particularly among patients who carry both variants.

Immune-Related Adverse Events of the Gastrointestinal System

Immune checkpoint inhibitors (ICI) are a form of immunotherapy that have revolutionized the treatment of a number of cancers. Specifically, they are antibodies targeted against established and emerging immune checkpoints, such as cytotoxic T-cell antigen 4 (CTLA4), programmed cell death ligand 1 (PD-L1) and programmed cell death 1 protein (PD-1) on CD8-positive T cells, which promote the destruction of tumor cells. While the immune checkpoint inhibitors are very effective in the treatment of a number of cancers, their use is limited by serious and in some cases life-threatening immune-related adverse events. While these involve many organs, one of the most prevalent serious adverse events is immune checkpoint inhibitor colitis, occurring in a significant proportion of patients treated with this therapy. In this review, we aim to broadly describe the immune-related adverse events known to occur within the gastrointestinal system and the potential role played by the intestinal microbiome.

Acute Severe Ulcerative Colitis: Optimal Strategies for Drug Therapy

Acute severe ulcerative colitis (ASUC) is a life-threatening medical emergency with considerable morbidity (30% to 40%). Patients with ASUC require hospitalization for prompt medical treatment, and colectomy is considered if medical therapy fails. Corticosteroids remain the primary initial therapy, although one-third of patients do not respond to treatment. Clinical data have indicated that cyclosporine, tacrolimus, and infliximab can be used to treat patients with ASUC who do not respond to intravenous corticosteroids. The effectiveness and safety of sequential therapy have recently been reported; however, the data are not convincing. Importantly, timely decision-making with rescue therapy or surgical treatment is critical to manage ASUC without compromising the health or safety of the patients. In addition, risk stratification and the use of predictive clinical parameters have improved the clinical outcome.of ASUC. Multidisciplinary teams that include inflammatory bowel disease experts, colorectal surgeons, and other medical staff contribute to the better management of patients with ASUC. In this review, we introduce current evidence and present a clinical approach to manage ASUC.

Subcutaneous Infliximab [CT-P13], a True Biologic 2.0. Real Clinical Practice Multicentre Study

Background: Inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis, is characterized by chronic relapsing intestinal inflammation. There are few data on the efficacy and safety in clinical practice of infliximab (CT-P13) in subcutaneous formulation (SC) for the treatment of patients with IBD. Methods: Multicenter, prospective study of patients with IBD in clinical remission, who had their treatment changed from intravenous (IV) infliximab to SC. Two groups of patients were evaluated according to whether they were on IV infliximab treatment at standard or intensified doses before the switch. Results: A total of 30 patients were on standard dosing and another 30 in intensified therapy. Treatment persistence in both groups at 6 months was greater than 95%. In both groups after the change, neither the biomarkers of inflammation nor the activity indices underwent significant changes at 3 and 6 months compared to the baseline value. Similarly, in both groups, infliximab trough levels showed a significant increase 3 and 6 months after the change to SC. No serious adverse events were registered. Conclusions: The CT-P13 SC brings a new anti-TNF era. Achieving much higher drug levels that are constant over time opens new paths to explore the management of patients with IBD: less immunogenicity, better perianal disease control and higher achievement of mucosal healing.

An Engineered Monovalent Anti-TNF-α Antibody with pH-Sensitive Binding Abrogates Immunogenicity in Mice following a Single Intravenous Dose

Therapeutic Abs directed toward TNF-α display significant immunogenicity in humans, frequently leading to lower serum concentrations of the Ab that are associated with lower treatment efficacy. The enhanced incidence of immunogenicity observed with this class of therapeutics may be mediated by the expression of TNF-α as a homotrimer, both as a soluble serum protein and as a membrane-associated protein (mTNF-α) on the surface of dendritic cells. The TNF-α homotrimer enables the formation of polyvalent Ab-TNF-α immune complexes (ICs) that enhance binding to FcR and neonatal FcR. Polyvalent ICs and Ab bound to mTNF-α on the surface of dendritic cells can internalize, traffic to the lysosomes, and be processed for presentation by MHC molecules. To diminish immunogenicity caused by trafficking of ICs and mTNF-α to the lysosomes, we engineered a monovalent format of adalimumab with pH-sensitive binding to TNF-α. The engineered variant, termed AF-M2637, did not cross-link TNF-α trimers and consequently formed small, nonprecipitating ICs only. AF-M2637 bound TNF-α with high affinity at pH 7.4 (EC50 = 1.1 nM) and displayed a significantly faster dissociation rate than adalimumab at pH 6.0. No immune response to AF-M2637 was detected in mice following a single i.v. dose. In contrast, rapid immunization was detected following the injection of a single i.v. dose of adalimumab, monovalent adalimumab, or the bivalent form of the pH-sensitive variant. These data suggest that ICs and mTNF-α both contribute to the immunogenicity of adalimumab in mice and provide a general strategy for engineering less immunogenic therapeutic TNF-α Abs.

[Perimyocarditis as a complication of a multiple drug therapy in the treatment of a severe ulcerative colitis episode]

HISTORY AND CLINICAL FINDINGS

 A 19-year-old patient presented as an inpatient with an acute flare-up of ulcerative colitis for about six weeks and symptom progression for one and a half weeks. The patient was treated with topical and oral 5-aminosalicylic acid (5-ASA) preparations and oral prednisolone. With an intensification of the prednisolone dose, administration of a monoclonal antibody (Vedolizumab) and antibiotic therapy, inpatient discharge against medical advice. Oral administration of ciprofloxacin due to continued elevated infection parameters. The 5-ASA administration was continued. In the following two weeks, recurrent episodes of fever and renewed inpatient admission.

INVESTIGATIONS AND DIAGNOSIS

 Microbiological detection of Acinetobacter ursingii in blood cultures. Echocardiographic evidence of pericardial effusion. Transesophageal echocardiography revealed no evidence of infective endocarditis. Serological evidence of elevated cardiac enzyme levels. An MRI scan of the heart confirmed the diagnosis of perimyocarditis.

TREATMENT AND COURSE

 Intensive medical care and resistogram-based antibiotic therapy with meropenem, stopping the topical and oral 5-ASA doses and not continuing the integrin antagonist therapy. In addition, start of guideline-based cardiac insufficiency therapy and change of therapy to a tumor necrosis factor alpha blocker. Under the accelerated application scheme, stabilization and improvement of the general condition protracted. After two months of hospitalization, the patient was discharged to outpatient care.

DISCUSSION

 Perimyocarditis may occur after long-term administration of 5-ASA. The integrin antagonist as a new therapy can also be a causal factor. Therapeutic management when the cause of the complaint is unclear depends on the symptoms and the most likely cause of the disease. If there is no response to therapy, carry out early re-evaluations.

Exposure-Response Characterization of Tofacitinib Efficacy in Moderate to Severe Ulcerative Colitis: Results From Phase II and Phase III Induction and Maintenance Studies

Tofacitinib is an oral small molecule JAK inhibitor for the treatment of ulcerative colitis. Relationships between plasma tofacitinib concentration and efficacy were characterized using exposure‐response (E‐R) models, with demographic and disease covariates evaluated as potential predictors of efficacy. Data were from phase II and III (OCTAVE Induction 1 and 2) induction studies, and a phase III maintenance study (OCTAVE Sustain). Induction studies included 1,355 patients (tofacitinib 0.5, 3, 10, or 15 mg b.i.d. or placebo). The maintenance study included 592 patients (tofacitinib 5 or 10 mg b.i.d. or placebo). E‐R models, including induction patients predicted placebo‐adjusted remission rates of 6.4% and 12.7% at week 8 for tofacitinib 5 and 10 mg b.i.d., respectively; corresponding rates in patients without prior tumor necrosis factor inhibitor (TNFi) failure were 12.8% and 20.4%. Estimates to achieve/maintain remission at week 52 of maintenance were 29% and 18% (tofacitinib 5 mg b.i.d.), and 41% and 26% (tofacitinib 10 mg b.i.d.), for patients in remission or not following induction, respectively. During maintenance, patients with prior TNFi failure had lower probability of remission on 5 mg b.i.d. (24.9%) than 10 mg b.i.d. (35.0%). Results indicated tofacitinib 10 mg b.i.d. was an appropriate induction dose but suggested efficacy with 5 mg b.i.d. in patients without prior TNFi failure. Tofacitinib 5 mg b.i.d. was efficacious for maintenance, although patients with prior TNFi failure might see additional benefit on 10 mg b.i.d. Per product labeling, recommended tofacitinib induction dose is 10 mg b.i.d., then maintenance at 5 mg b.i.d. For patients who lose response during maintenance, 10 mg b.i.d. may be considered, limited to the shortest duration.

Clinicaltrials.gov: NCT00787202; NCT01465763; NCT01458951; and NCT01458574.

Optimizing Therapies Using Therapeutic Drug Monitoring: Current Strategies and Future Perspectives

Therapeutic drug monitoring (TDM) has emerged as a strategy for treatment optimization in inflammatory bowel diseases to maximize benefit and to reach more stringent, objective end points. Optimal drug concentrations in inflammatory bowel disease vary according to treatment target, disease phenotype, inflammatory burden, and timing of sampling during the treatment cycle. This review provides an update on TDM with biologic and oral small molecules, evaluates the role of reactive vs proactive TDM, and identifies the gaps in current evidence. In the future, adaptations to how we use TDM may contribute further to the goal of personalized treatment in patients with IBD.

Recent advancements in clearance monitoring of monoclonal antibodies in patients with inflammatory bowel diseases

INTRODUCTION

Less than 50% of patients with inflammatory bowel diseases (IBD) receiving monoclonal antibody (mAb) therapy achieve endoscopic remission. Poor outcomes may indicate a need for dose optimization. During therapeutic drug monitoring (TDM), drug concentrations are measured, and when found too low, dosage regimen escalations are performed. To date, benefits of TDM of mAbs in patients with IBD are uncertain.

AREAS COVERED

This review presents an overview of what clearance monitoring is, how it can be performed, and why and when it may be valuable in treating patients with IBD. Virtual patients were used for illustration. A literature search was performed to summarize current evidence for clearance monitoring in IBD and other disease settings.

EXPERT OPINION

During clearance monitoring, mAb clearance is calculated and monitored over time. Higher mAb clearance in patients with IBD has been associated with higher target load (target-mediated drug disposition), protein-losing enteropathy (fecal drug loss), and immunogenicity. Although not prospectively confirmed, clearance monitoring might facilitate identification of (yet) asymptomatic disease flares or presence of (yet) undetectable anti-drug antibodies. Furthermore, clearance monitoring may be used to predict treatment outcomes. Whether dosage regimen adjustments can modify the clearance time course and the treatment outcome is to be determined.

Discovery of new long noncoding RNAs associated with ulcerative colitis with a novel general microarray expression data

UC is a chronic, nonspecific disease and characterized by a chronic relapsing intestinal inflammation, which puts a person at a higher risk of developing bowel cancer, while the causes of UC are unknown. Recently, with the development of microarray technology, more and more studies are focusing on the potential roles of long noncoding RNAs (lncRNAs) in the pathogenesis of diseases. The purpose of this study is to devise a method, based on cDNA microarray probe genomics data, to computationally determine the potential function of evolutionary conserved lncRNAs in ulcerative colitis (UC). We analysed a total of 12,593 microarray probes present in the Ensembl, OMIM, UniGene, and Gene Ontology databases. We found that lncRNA n385775 was significantly higher (P < 0.001) in patients with active UC, while n336281 (P = 0.017), n341081 (P = 0.041), and n387236 (P = 0.006) were significantly lower. Then, we validated our findings by measuring the expression of lncRNAs in colon tissue samples from patients affected by UC. Moreover, we validated the expression pattern of the lncRNAs in two cell lines, Caco2/bbe and T84, treated with TNF-α. In Caco2/bbe cells, lncRNA n385775 was significantly upregulated after TNF-α treatment (P = 0.002). This study reports a novel method to re- annotate the transcriptome expression profile from existing cDNA microarray data as a potential approach to investigate the function of lncRNAs in UC.

Ustekinumab induction concentrations are associated with clinical and biochemical outcomes at week 12 of treatment in Crohn's disease

BACKGROUND

We investigated relationships between induction ustekinumab levels and clinical and biochemical outcomes in Crohn's disease.

METHODS

Following standard IV induction, ustekinumab levels were measured at week 2 (wk2) and week 6 (wk6). Ustekinumab levels were compared in patients receiving 260, 390 and 520 mg at induction. Crohn's disease activity index (CDAI), serum albumin, C-reactive protein (CRP) and fecal calprotectin (FCP) were measured at baseline and week 12 (wk12). Associations between ustekinumab levels and these parameters were assessed. Ustekinumab levels were compared between patients requiring dose intensification within one year of induction and those remaining on standard dosing.

RESULTS

Of 23 wk2 ustekinumab levels, 22(95.7%) were above the upper limit of quantification of the assay (25 µg/mL). Median wk6 ustekinumab level (n = 25) was 14.2 μg/mL [interquartile range (IQR), 9.6-20.1]. Median wk6 ustekinumab levels in patients receiving 260, 390 and 520 mg were 8.6, 16.3 and 25.0 µg/mL, respectively, P = 0.01. There were significant correlations between baseline albumin and wk6 ustekinumab levels; r = 0.644 [95% confidence interval (CI), 0.304-0.839], P < 0.001, and between baseline FCP and wk6 ustekinumab levels; r = -0.678 (95% CI, -0.873 to -0.296), P < 00.01. Median wk12 CDAI (n = 18), CRP (n = 22) and FCP (n = 13) were 78 (IQR, 52.5-152), 1.75 mg/L (IQR, 0.93-7.03) and 746 μg/g (IQR, 259-2100), respectively. There were significant correlations between wk6 ustekinumab levels and wk12 CDAI; r = -0.513 (95% CI, -0.796 to -0.046), P = 0.03; and between wk6 ustekinumab levels and wk12 CRP; r = -0.578 (95% CI, -0.808 to -0.194), P < 0.01. Wk6 ustekinumab levels were lower in patients undergoing subsequent dose intensification; 12.5 vs. 19.6 µg/mL, P = 0.04.

CONCLUSION

Wk6 ustekinumab levels are significantly associated with baseline Crohn's disease biomarkers and subsequent clinical and biochemical outcomes.

Acute severe ulcerative colitis: management advice for internal medicine and emergency physicians

Acute severe ulcerative colitis is a medical emergency that warrants in-patient management. This is best served within a multidisciplinary team setting in specialised centres or with expert consultation. Intravenous corticosteroids remain the cornerstone in the management of ASUC and should be initiated promptly, along with general management measures and close monitoring of patients. Unfortunately, one-third of patients will fail to respond to steroids. Response to intravenous corticosteroid therapy needs to be assessed on the third day and rescue therapies, including cyclosporine and infliximab, should be offered to patients not responding. Choice of rescue therapy depends on experience, drug availability and factors associated with each individual patient, such as comorbidities, previous medications or contra-indications to therapy. Patients who have not responded within 7 days to rescue therapy must be considered for surgery. Surgery is a treatment option in ASUC and should not be delayed in cases of failure of medical therapy, because such delays increase surgical morbidity and mortality. This review summarises the current management of acute severe ulcerative colitis and discusses potential future developments.

The roles of different Bacteroides fragilis strains in protecting against DSS-induced ulcerative colitis and related functional genes

The role of supplementation with different Bacteroides fragilis (B. fragilis) strains in alleviating ulcerative colitis (UC) is unclear due to the controversial results from animal experiments. In this study, three B. fragilis strains were evaluated for their ability to alleviate dextran sulfate sodium (DSS)-induced UC in C57BL/6J mice. We analyzed the anti-inflammatory effects of different B. fragilis strains and the changes they caused in the intestinal microbiota composition, intestinal epithelial permeability, cytokine concentrations, protein expression of nuclear factor kappa-B (NF-κB) and the underlying specific genes. The results showed that when orally administered, the different B. fragilis strains exerted different effects on the assessed parameters of the mice. The results of real-time quantitative polymerase chain reaction and immunofluorescence staining showed that the supplementation of B. fragilis FSHCM14E1, but not FJSWX11BF, enhanced the expression of the tight-junction proteins ZO-1, occludin and claudin-1. Western blot analysis showed that the anti-inflammatory effects of B. fragilis FSHCM14E1 were related to the NF-κB pathway. Genomic analysis suggested that the anti-inflammatory effects of FSHCM14E1 may be mediated through specific genes associated with defense mechanisms and the secretion of SCFAs. Overall, this study indicates the therapeutic potential of B. fragilis FSHCM14E1 for the prevention of UC.

Treatment of acute severe ulcerative colitis using accelerated infliximab regimen based on infliximab trough level: A case report

BACKGROUND

Acute severe ulcerative colitis (ASUC) is a complication of ulcerative colitis associated with high levels of circulating tumor necrosis factor alpha, due to the intense inflammation and faster stool clearance of anti-tumor necrosis factor drugs. Dose-intensified infliximab treatment can be beneficial and is associated with lower rates of colectomy. The aim of the study was to present a case of a patient with ASUC and megacolon, treated with hydrocortisone and accelerated scheme of infliximab that was monitored by drug trough level.

CASE SUMMARY

A 22-year-old female patient diagnosed with ulcerative colitis, presented with diarrhea, rectal bleeding, abdominal pain, vomiting, and distended abdomen. During investigation, a positive toxin for Clostridium difficile and colonic dilatation of 7 cm consistent with megacolon were observed. She was treated with oral vancomycin for pseudomembranous colitis and intravenous hydrocortisone for severe colitis, which led to the resolution of megacolon. Due to the persistent severe colitis symptoms, infliximab 5 mg/kg was prescribed, monitored by drug trough level (8.8 μg/mL) and fecal calprotectin of 921 μg/g (< 30 μg/g). Based on the low infliximab trough level after one week from the first infliximab dose, the patient received a second infusion at week 1, consistent with the accelerated regimen (infusions at weeks 0, 1, 2 and 6). We achieved a positive clinical and endoscopic response after 6 mo of therapy, without the need for a colectomy.

CONCLUSION

Infliximab accelerated infusions can be beneficial in ASUC unresponsive to the treatment with intravenous corticosteroids. Longitudinal studies are necessary to define the best therapeutic drug monitoring and treatment regimen for these patients.

Baseline Clearance of Infliximab Is Associated With Requirement for Colectomy in Patients With Acute Severe Ulcerative Colitis

BACKGROUND & AIMS

Hospitalized patients with acute severe ulcerative colitis (ASUC) often require surgery. Although the tumor necrosis factor antagonist infliximab is an effective salvage therapy to prevent colectomy in patients with ASUC, optimal dosing is unclear. Calculated infliximab clearance has been associated with important outcomes in patients with ulcerative colitis, but its utility in patients with ASUC has not been established. We assessed the relationship between calculated the baseline infliximab clearance before infliximab salvage therapy and the requirement for colectomy in patients hospitalized for ASUC.

METHODS

We obtained data from hospitalized patients with ASUC who initiated infliximab therapy. We then calculated the baseline infliximab drug clearance in these patients based on an existing formula. The primary aim was to compare clearance between patients who required colectomy 6 months later and patients who did not require colectomy. Receiver operating characteristic curve analyses evaluated clearance thresholds for colectomy. Multivariable logistic regression analysis evaluated factors associated with colectomy.

RESULTS

In 39 patients with ASUC, the median baseline calculated clearance was higher in patients requiring colectomy at 6 months than in patients without colectomy (0.733 vs 0.569 L/d; P = .005). An infliximab clearance threshold of 0.627 L/d identified patients who required colectomy with 80.0% sensitivity and 82.8% specificity (area under the curve, 0.80). A higher proportion of patients with infliximab clearance of 0.627 L/d or more underwent colectomy within 6 months (61.5%) than patients with lower infliximab clearance values (7.7%) (P = .001). Multivariable analysis identified baseline infliximab clearance as the only factor associated with colectomy. The infliximab dose in the hospital was higher in patients who required colectomy. Results were similar at 30 days and 1 year.

CONCLUSIONS

In patients hospitalized with ASUC, higher values of calculated infliximab clearance before infliximab administration is associated with higher rates of colectomy. Although patients who required colectomies received higher doses, data on infliximab concentrations are lacking. Infliximab pharmacokinetic models are needed for patients with ASUC to allow comparative trials on clearance-based vs standard dosing.

Hypoalbuminemia and Bandemia Predict Failure of Infliximab Rescue Therapy in Acute Severe Ulcerative Colitis

BACKGROUND AND AIMS

Infliximab rescue therapy is effective in patients with corticosteroid refractory acute severe ulcerative colitis, but predictors of response remain poorly understood. We aimed to identify predictors of colectomy in this high-risk patient population.

METHODS

Patients hospitalized with acute severe ulcerative colitis who received infliximab after failing intravenous corticosteroid therapy between July 2012 and June 2017 were retrospectively identified. Stepwise regression with backward elimination was used to identify predictors of colectomy at 90 days and 1 year. Ninety-day and 1-year colectomy rates were compared between the patients who received 5 mg/kg and 10 mg/kg IFX rescue dose.

RESULTS

Sixty-three patients met the eligibility criteria. Twenty-nine patients received 5 mg/kg, and 34 received 10 mg/kg infliximab dose. Serum albumin on admission (OR 0.10; p = 0.04) and band neutrophil percentage at the time of infliximab administration (OR 1.21; p = 0.02) were independent predictors of 90-day colectomy. A combination of serum albumin ≤ 2.5 g/dl and band neutrophil count ≥ 13% had a 100% positive predictive value for 90-day colectomy. Unadjusted 90-day and 1-year colectomy rates were similar in the 5 mg/kg and 10 mg/kg infliximab groups. After adjusting for confounding factors, 10 mg/kg infliximab dose was potentially protective for 90-day (OR 0.07; p = 0.06) but not for 1-year colectomy (OR 0.19; p = 0.16).

CONCLUSIONS

Bandemia and low serum albumin are independent predictors of failure of infliximab rescue therapy in acute severe ulcerative colitis. Serum albumin ≤ 2.5 g/dl and band neutrophil count ≥ 13% had a 100% positive predictive value for 90-day colectomy.

Early Serum Infliximab Levels in Pediatric Ulcerative Colitis

Background: Data on serum infliximab concentrations during induction in pediatric ulcerative colitis are limited. The study aim is to evaluate the relationship between serum infliximab concentrations during induction and short-term clinical remission in children with ulcerative colitis. Methods: We carried out a prospective, multi-center cohort study in pediatric patients with ulcerative colitis. Serum infliximab concentrations were collected at peak dose #1, week 1, trough pre-dose #2, and trough pre-dose #3. Infliximab dosing was left to investigator discretion. Clinical remission was defined by pediatric ulcerative colitis activity index <10 at week 8. Results: Twenty-four of thirty-four subjects (71%) achieved clinical remission at week 8. The median infliximab concentrations were 33.0 μg/mL (interquartile range: 26.5-52.1 μg/mL) pre-dose #2 and 22.5 μg/mL (interquartile range:15.9-32.3 μg/mL) pre-dose #3. Trough pre-dose #2 infliximab concentration yielded area under receiver operator characteristic curve 0.7, 95% CI: 0.5-0.9 in predicting week 8 clinical remission; a cut-off of 33.0 μg/mL yielded 62.5% sensitivity, 66.7% specificity. Trough pre-dose #3 infliximab concentrations were lower for subjects <10 years compared to ≥ 10 years [median 15.9 μg/mL, interquartile range (IQR) 8.5-21.8 μg/mL vs. 27.7 μg/mL, IQR 17.2-46.7 μg/mL, p = 0.01] and correlated with baseline weight (Spearman's rank correlation coefficient 0.45, p = 0.01). The median half-life following first IFX dose was 6.04 days (IQR 5.3-7.9 days). Conclusions: Infliximab concentrations ≥33 μg/mL prior to the second dose were associated with week 8 clinical remission. As young age and low body weight impact infliximab concentration, prospective studies with proactive adjustment in pediatric patients with ulcerative colitis should be carried out. Clinicians caring for children with UC should diligently adjust and monitor infliximab to optimize response.

Ustekinumab Pharmacokinetics and Exposure Response in a Phase 3 Randomized Trial of Patients With Ulcerative Colitis

BACKGROUND & AIMS

The efficacy of antibody-based therapeutics depends on their pharmacokinetics. The pharmacokinetic and exposure response profiles of ustekinumab, a monoclonal antibody against interleukin 12/interleukin 23, are known in patients with Crohn's disease, yet there are few data from patients with ulcerative colitis. We characterized ustekinumab's pharmacokinetics, exposure response, and optimal serum concentrations in patients with ulcerative colitis.

METHODS

We collected data from 2 phase 3 trials (1 induction and 1 maintenance), in which patients with moderate to severe ulcerative colitis received an intravenous induction dose of ustekinumab (130 mg, n = 320; or approximately 6 mg/kg, n = 322). Responders were assigned randomly to groups that received subcutaneous maintenance ustekinumab (90 mg) every 8 weeks (n = 176) or 12 weeks (n = 172), or placebo (n = 175). We evaluated the association between ustekinumab concentration and efficacy, serum based on clinical effects (Mayo score), histologic features, and inflammation (measurement of C-reactive protein, fecal calprotectin, and fecal lactoferrin), as well as safety (infections, serious infections, and serious adverse events), during induction and maintenance therapy. Optimal serum concentrations of ustekinumab were identified using receiver operating characteristic curve analyses.

RESULTS

In patients with ulcerative colitis, dose-proportional serum concentrations of ustekinumab, unaffected by prior biologic or concomitant immunomodulator therapy, reached steady state by the second maintenance dose; the median trough concentration for dosing every 8 weeks was approximately 3-fold that of dosing every 12 weeks. Serum concentrations were associated with clinical and histologic features of efficacy and normalization of inflammation markers. The week-8 concentration threshold for induction of response was 3.7 μg/mL. A steady-state trough serum concentration of 1.3 μg/mL or higher was associated with a higher rate of clinical remission compared with patients who had lower serum concentrations. Serum concentrations of ustekinumab were not associated with infections, serious infections, or serious adverse events.

CONCLUSIONS

In an analysis of data from 2 phase 3 trials of patients with ulcerative colitis, we found that serum concentrations of ustekinumab were proportional to dose, unaffected by prior biologic or concomitant immunomodulator therapies, associated with clinical and histologic efficacy and markers of inflammation, and were not associated with safety events at doses evaluated. Ustekinumab pharmacokinetics are consistent between patients with Crohn's disease vs ulcerative colitis.

Biological therapy in pediatric age

Biological therapies, especially blocking tumor necrosis factor-α (TNFα) agents have radically changed the therapeutic approach and disease course of pediatric inflammatory bowel disease (IBD). In particular, drugs such as infliximab (IFX) and adalimumab (ADA) have been demonstrated to be effective in inducing and maintaining corticosteroid-free remission in both adult and pediatric patients with Crohns Disease (CD) and Ulcerative colitis (UC). Biosimilar biological (BioS) therapy is increasingly being used in pediatric age even though most knowledge on the safety and efficacy of these agents is based on IFX in adult IBD data. Studies show high rates of clinical response and remission in both IFX naïve patients and in patients switched from originator to BioS with similar risks of adverse events (AEs) as those reported with IFX originator. In the present review indications, efficacy and AEs of biological therapy in pediatric IBD will be discussed, as well as the role of other biological agents such as Golimumab, Vedolizumab and Ustekinumab, the role of BioS biological therapy and utility of therapeutic drug monitoring in clinical practice.

Positioning Biologic Therapies in the Management of Pediatric Inflammatory Bowel Disease

The incidence and prevalence of pediatric inflammatory bowel disease (IBD) are rising worldwide, with a steep increase in children under 5 years of age. Compared to adult IBD, pediatric IBD presents with a more severe, aggressive phenotype and unique complications, notably growth impairment. Treatment goals include achieving intestinal healing, reaching growth potential, and optimizing quality of life, all while limiting drug toxicities. In the last 2 decades, the advent of anti-tumor necrosis factor (TNF) α agents has significantly increased the potential to reach these goals. However, nonresponse or loss of response to anti- TNFα agents is still encountered in approximately one-third of patients. Although the development of novel biologic therapies has offered new alternatives in recent years, the use of these therapies in the pediatric setting has been limited due to delayed approval. This article summarizes the key evidence for biologic agents currently used in the treatment of pediatric IBD and discusses challenges and barriers unique to pediatric drug development.

Usefulness of monitoring antitumor necrosis factor serum levels during the induction phase in patients with Crohn's disease

AIMS

The aims of this study were (a) to know the kinetics of antitumor necrosis factor (TNF) drug serum levels during the induction phase in patients with Crohn's disease; (b) to identify variables associated with these levels; and (c) to assess the relation between these levels and short-term effectiveness in Crohn's disease patients.

METHODS

Patients with Crohn's disease naïve to anti-TNF treatment were prospectively included. Remission was defined as a Crohn's disease activity index (CDAI) score <150 after 14 weeks of treatment. Blood samples were obtained at baseline and at weeks 4, 8, and 14. Adalimumab and infliximab levels were measured, receiver operating characteristic (ROC) curves were constructed, and the area under the ROC curve was calculated.

RESULTS

One-hundred fifty patients with Crohn's disease were included, 79 (53%) received infliximab and 71 (47%) had CDAI > 150 at study entry. At week 14, 52 out of 71 patients with CDAI > 150 at baseline (73%) had clinical remission. There were no differences in infliximab levels between patients with and without remission (8 vs. 9.1 μg/mL, P > 0.05) or with and without response (7 vs. 11 μg/mL, P > 0.05) at week 14. There was a trend to higher levels of adalimumab concentration in responders in comparison with nonresponders (13 vs. 6.7 μg/mL, P = 0.05) and in patients who achieved remission in comparison with nonremitters (13.5 vs. 8.4 μg/mL, P = 0.06). In the multivariate analysis, no variable was predictive of short-term remission, including infliximab and adalimumab serum levels.

CONCLUSION

Determining anti-TNF serum levels during the induction phase is not useful for predicting short-term remission in patients with Crohn's disease.

Post-induction infliximab trough levels and disease activity in the clinical evolution of pediatric ulcerative colitis

BACKGROUND AND AIMS

Recent adult evidence suggests that infliximab (IFX) trough levels (TL) in patients with severe ulcerative colitis (UC) may be decreased. The aims of our study were to compare post-induction IFX TL of children with severe versus moderate UC and to evaluate short- and long-term outcomes.

METHODS

In this single-center retrospective study, children with a diagnosis of UC starting IFX with a Pediatric Ulcerative Colitis Activity Index (PUCAI) ≥35 and with available post-induction TL were recruited. UC characteristics, IFX dosage and interval, primary non-response, IFX failure, and surgery after 24 months were collected. Post induction TL, anti-IFX antibodies, and laboratory evaluations at the time of starting IFX were also acquired.

RESULTS

A total of 90 children were enrolled, of whom 39 (43.3%) were classified as severe UC and 51 (56.6%) as moderate UC. Median post-induction IFX TL were lower in severe UC versus moderate group (5.5 vs 10.3; p = 0.03), despite a more frequently intensified IFX regimen. Children in the higher TL quartiles showed increased rates of clinical, biological, and combined remission (p = 0.04, p < 0.001, and p = 0.01, respectively). In a multivariate analysis, a PUCAI ≥65 and time interval from last IFX infusion were the only predictors associated with IFX TL. At 24 months, children in the higher TL quartiles had a decreased risk of IFX failure (p = 0.002). The severe UC group showed a higher risk of IFX failure at 24 months (16/23 (41%) vs. 11/40 (21.6%); p = 0.05). Kaplan-Meier methods demonstrated a trend toward statistical significance, with a two-year cumulative colectomy rate of 15.38% (95% confidence interval (CI) 8.1-15.6%) in children with severe UC and 3.92% (95% CI 2.9-10.8%) in patients with moderate UC (logrank test p = 0.06).

CONCLUSIONS

Children starting IFX with severe UC showed lower post-induction TL and poor disease outcomes. Achieving adequate TL was associated with better efficacy outcomes.

Inflammatory bowel disease position statement of the Italian Society of Colorectal Surgery (SICCR): ulcerative colitis

The Italian Society of Colorectal Surgery (SICCR) promoted the project reported here, which consists of a Position Statement of Italian colorectal surgeons to address the surgical aspects of ulcerative colitis management. Members of the society were invited to express their opinions on several items proposed by the writing committee, based on evidence available in the literature. The results are presented, focusing on relevant points. The present paper is not an alternative to available guidelines; rather, it offers a snapshot of the attitudes of SICCR surgeons about the surgical treatment of ulcerative colitis. The committee was able to identify some points of major disagreement and suggested strategies to improve the quality of available data and acceptance of guidelines.

Up-to-date surgery for ulcerative colitis in the era of biologics

Introduction: In recent decades, biologics have resulted in significantly improved medical management of ulcerative colitis (UC). Rates of surgery for UC are declining. However, there is still a controversial question of the relation of biologics to postoperative adverse outcomes and the most appropriate timing for operative intervention.Areas covered: In this review, we explore the updated treatment algorithm of acute severe colitis, describe postoperative outcomes in patients exposed to biologics preoperatively, and discuss the primary indications for staging surgery in chronic refractory cases, largely with prolonged medical therapy.Expert opinion: Delaying pouch construction to when patients are in better health is suggested as a safer strategy over the long term. The surgical management of UC patients in the biologic era needs to be individualized, and a case-based multidisciplinary decision is critical for improved outcomes and a reduction of morbidity and mortality.

British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults

Ulcerative colitis and Crohn's disease are the principal forms of inflammatory bowel disease. Both represent chronic inflammation of the gastrointestinal tract, which displays heterogeneity in inflammatory and symptomatic burden between patients and within individuals over time. Optimal management relies on understanding and tailoring evidence-based interventions by clinicians in partnership with patients. This guideline for management of inflammatory bowel disease in adults over 16 years of age was developed by Stakeholders representing UK physicians (British Society of Gastroenterology), surgeons (Association of Coloproctology of Great Britain and Ireland), specialist nurses (Royal College of Nursing), paediatricians (British Society of Paediatric Gastroenterology, Hepatology and Nutrition), dietitians (British Dietetic Association), radiologists (British Society of Gastrointestinal and Abdominal Radiology), general practitioners (Primary Care Society for Gastroenterology) and patients (Crohn's and Colitis UK). A systematic review of 88 247 publications and a Delphi consensus process involving 81 multidisciplinary clinicians and patients was undertaken to develop 168 evidence- and expert opinion-based recommendations for pharmacological, non-pharmacological and surgical interventions, as well as optimal service delivery in the management of both ulcerative colitis and Crohn's disease. Comprehensive up-to-date guidance is provided regarding indications for, initiation and monitoring of immunosuppressive therapies, nutrition interventions, pre-, peri- and postoperative management, as well as structure and function of the multidisciplinary team and integration between primary and secondary care. Twenty research priorities to inform future clinical management are presented, alongside objective measurement of priority importance, determined by 2379 electronic survey responses from individuals living with ulcerative colitis and Crohn's disease, including patients, their families and friends.

Inpatient Management of Acute Severe Ulcerative Colitis

Acute severe ulcerative colitis (ASUC) is a potentially life-threatening presentation of ulcerative colitis that in nearly all cases requires inpatient management and coordinated care from hospitalists, gastroenterologists, and surgeons. Even with ideal care, a substantial proportion of patients will ultimately require colectomy, but most patients can avoid surgery with intravenous corticosteroid treatment and if needed, appropriate rescue therapy with infliximab or cyclosporine. In-hospital management requires not only therapies to reduce the inflammation at the heart of the disease process, but also to avoid complications of the disease and its treatment. Care for ASUC must be anticipatory, with patient education and evaluation starting at the time of admission in advance of the possible need for urgent medical or surgical rescue therapy. Here we outline a general approach to the treatment of patients hospitalized with ASUC, highlighting the common pitfalls and critical points in management.

British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults

Ulcerative colitis and Crohn's disease are the principal forms of inflammatory bowel disease. Both represent chronic inflammation of the gastrointestinal tract, which displays heterogeneity in inflammatory and symptomatic burden between patients and within individuals over time. Optimal management relies on understanding and tailoring evidence-based interventions by clinicians in partnership with patients. This guideline for management of inflammatory bowel disease in adults over 16 years of age was developed by Stakeholders representing UK physicians (British Society of Gastroenterology), surgeons (Association of Coloproctology of Great Britain and Ireland), specialist nurses (Royal College of Nursing), paediatricians (British Society of Paediatric Gastroenterology, Hepatology and Nutrition), dietitians (British Dietetic Association), radiologists (British Society of Gastrointestinal and Abdominal Radiology), general practitioners (Primary Care Society for Gastroenterology) and patients (Crohn's and Colitis UK). A systematic review of 88 247 publications and a Delphi consensus process involving 81 multidisciplinary clinicians and patients was undertaken to develop 168 evidence- and expert opinion-based recommendations for pharmacological, non-pharmacological and surgical interventions, as well as optimal service delivery in the management of both ulcerative colitis and Crohn's disease. Comprehensive up-to-date guidance is provided regarding indications for, initiation and monitoring of immunosuppressive therapies, nutrition interventions, pre-, peri- and postoperative management, as well as structure and function of the multidisciplinary team and integration between primary and secondary care. Twenty research priorities to inform future clinical management are presented, alongside objective measurement of priority importance, determined by 2379 electronic survey responses from individuals living with ulcerative colitis and Crohn's disease, including patients, their families and friends.

Special considerations for biologic medications in pediatric ulcerative colitis

Introduction: More extensive disease, high rates of corticosteroid refractory and dependent disease, and the potential impact of disease on growth and development differentiate inflammatory bowel disease in children from adults. This is particularly evident in ulcerative colitis where pancolitis predominates, success of mesalamine alone in achieving remission is less than 50%, and there is a high need for immunomodulator or biologic therapies.Areas Covered: This review describes the use of infliximab, adalimumab, golimumab, and vedolizumab in the treatment of children with ulcerative colitis but is limited in scope due to the paucity of controlled clinical trials. A search of existing literature with keywords of these specific biological therapies as well as 'pediatric', 'ulcerative colitis,' and 'inflammatory bowel disease' was used to complete this review.Expert Opinion: Therapeutic drug monitoring has become standard of care when assessing dosing and changes in therapy and will play a role in future treatment planning.

Clinical Pharmacokinetics and Pharmacodynamics of Infliximab in the Treatment of Inflammatory Bowel Disease

Infliximab was the first monoclonal antibody to be approved for the treatment of pediatric and adult patients with moderately to severely active Crohn's disease (CD) and ulcerative colitis (UC). It has been shown to induce and maintain both clinical remission and mucosal healing in pediatric and adult patients with inflammatory bowel disease (IBD) who are unresponsive or refractory to conventional therapies. The administration of infliximab is weight-based and the drug is administered intravenously. The volume of distribution of infliximab is low and at steady state ranges from 4.5 to 6 L. Therapeutic monoclonal antibodies, such as immunoglobulins, are cleared from the circulation primarily by catabolism. Median infliximab half-life is approximately 14 days. Infliximab concentration-time data in patients with CD and UC have been shown to be highly variable within an individual patient over time and between individuals by multiple population pharmacokinetic models. Covariates that have been identified to account for a part of the observed inter- and intra-individual variability in clearance are the presence of antidrug antibodies, use of concomitant immunomodulators, degree of systemic inflammation, serum albumin concentration, and body weight, which can affect the pharmacodynamic response. This article provides a comprehensive review of the clinical pharmacokinetics and pharmacodynamics of infliximab, as well as the role of therapeutic drug monitoring in the treatment of IBD.

Maneuvering Clinical Pathways for Ulcerative Colitis

PURPOSE OF REVIEW

Recent years have brought about several advances in the treatment of patients with ulcerative colitis (UC). Here, we discuss salient recommendations of recent treatment guidelines; review the efficacy, safety, and real-world data of vedolizumab and tofacitinib; appraise their place vis-à-vis established agents; and consider the newly proposed approaches of risk-stratified and treat-to-target therapy.

RECENT FINDINGS

Once daily oral mesalamine dosing is equivalent to split dosing in mild-moderate UC. Real-world data are accumulating on the effectiveness and safety of vedolizumab for moderate to severe UC, while there are few such data on the most recently approved agent, tofacitinib. High-dose infliximab is being investigated for severe UC. New approaches are challenging the established paradigm of selecting therapy based on current disease activity. The risk-stratified approach incorporates long-term risk as well as the current burden of inflammation. The treat-to-target approach aims at improved long-term outcomes by adjusting therapy to resolve intestinal inflammation. The therapeutic options for UC are continually expanding. Risk-stratified therapy and the treat-to-target approach represent paradigm shifts in UC management. Optimal disease control requires an individualized approach that takes into consideration current inflammatory burden, long-term risk, patient preferences, and ongoing assessment of response to treatment.

Practice pattern variability in the management of acute severe colitis: a UK provider survey

INTRODUCTION

Lack of comparative trial data on dosing regimens of infliximab in patients with acute severe ulcerative colitis (ASUC) failing intravenous corticosteroids has resulted in variability of rescue regimes in ASUC with potential impact on clinical outcomes. We aimed to evaluate practice variability and physician perspectives in decision-making with rescue therapy.

METHODOLOGY

An internet-based survey of members of the inflammatory bowel disease (IBD) section of the British Society of Gastroenterology was conducted. The survey evaluated provider characteristics and general practice in the setting of ASUC, followed by a vignette with linked questions.

RESULTS

The response rate of the survey was 31% (209/682 IBD section members). 134 (78%) reported they would use standard infliximab dose (5 mg/kg) while 37 (22%) favoured a higher front-loading dose of 10 mg/kg citing low albumin, high C-reactive protein as their reason for their preference. IBD specialists chose the higher front-loading dose more often compared with other gastroenterologists (p=0.01) In the specific case vignette, accelerated induction (AI) was favoured by 51% of the respondents while 25% used the standard induction regime and 19% favoured colectomy. IBD specialists more often favoured AI compared with other gastroenterologists (p=0.03) with the main reason being presence of predictors of low infliximab levels (74%). The reasons cited for favouring standard induction (n=57) included lack of evidence for AI (18), their usual practice (11), unlicensed regime (7), and safety concerns (4).

CONCLUSIONS

There are significant variations in practice in the use of infliximab rescue therapies with an urgent need for development of care pathways to standardise practice.

Intensified Infliximab Induction is Associated with Improved Response and Decreased Colectomy in Steroid-Refractory Paediatric Ulcerative Colitis

BACKGROUND

Infliximab pharmacokinetics in steroid-refractory [SR] ulcerative colitis [UC] suggest a need for higher dosing, but data concerning efficacy of intensification in this setting are lacking in children and inconsistent overall.

METHODS

Paediatric patients [N = 125] treated with infliximab for SR or steroid-dependent UC were retrospectively reviewed. Outcomes [clinical response and remission, colectomy, mucosal healing, safety] with standard vs intensified induction [mean induction dose ≥7 mg/kg or interval ≤5 weeks between doses 1 and 3] were compared.

RESULTS

Among 125 patients [median age 14 years, median UC duration 0.7 years, 74 SR], 73 [58%] received standard induction and 52 [42%] received intensified induction. Overall, 73 [58%] achieved remission (judged by physician global assessment [PGA] and paediatric UC activity index [PUCAI]≤10]. Among patients in remission, 7 [10%] experienced secondary loss of response by a median of 0.7 [IQR 0.4-1.0] years. Of the 74 SR patients, 17 [23%] underwent colectomy, and of the 51 steroid-dependent patients, 12 [24%] underwent colectomy. Intensified induction in SR patients was associated with a higher chance of remission (hazard ratio [HR] 3.2, p = 0.02) and a lower chance of colectomy [HR 0.4, p = 0.05], but did not improve outcomes in steroid-dependent patients. During follow-up, 46/73 [63%] patients in remission had regimen individualization, with similar rates of return to standard dosing after 1 year between those with initial intensified or standard induction. Follow-up endoscopy, performed in 35/73 patients in remission, demonstrated mucosal healing for 66%. Adverse events were rare, despite use of intensified regimens.

CONCLUSIONS

These data suggest a benefit from intensified infliximab induction specifically among children with steroid-refractory UC. Prospective studies comparing dosing regimens and incorporating therapeutic drug monitoring should be undertaken.

Systematic Review and Meta-analysis: Optimal Salvage Therapy in Acute Severe Ulcerative Colitis

BACKGROUND

Infliximab is an effective salvage therapy in acute severe ulcerative colitis; however, the optimal dosing strategy is unknown. We performed a systematic review and meta-analysis to examine the impact of infliximab dosage and intensification on colectomy-free survival in acute severe ulcerative colitis.

METHODS

Studies reporting outcomes of hospitalized steroid-refractory acute severe ulcerative colitis treated with infliximab salvage were identified. Infliximab use was categorized by dose, dose number, and schedule. The primary outcome was colectomy-free survival at 3 months. Pooled proportions and odds ratios with 95% confidence intervals were reported.

RESULTS

Forty-one cohorts (n = 2158 cases) were included. Overall colectomy-free survival with infliximab salvage was 79.7% (95% confidence interval [CI], 75.48% to 83.6%) at 3 months and 69.8% (95% CI, 65.7% to 73.7%) at 12 months. Colectomy-free survival at 3 months was superior with 5-mg/kg multiple (≥2) doses compared with single-dose induction (odds ratio [OR], 4.24; 95% CI, 2.44 to 7.36; P < 0.001). However, dose intensification with either high-dose or accelerated strategies was not significantly different to 5-mg/kg standard induction at 3 months (OR, 0.70; 95% CI, 0.39 to 1.27; P = 0.24) despite being utilized in patients with a significantly higher mean C-reactive protein and lower albumin levels.

CONCLUSIONS

In acute severe ulcerative colitis, multiple 5-mg/kg infliximab doses are superior to single-dose salvage. Dose-intensified induction outcomes were not significantly different compared to standard induction and were more often used in patients with increased disease severity, which may have confounded the results. This meta-analysis highlights the marked variability in the management of infliximab salvage therapy and the need for further studies to determine the optimal dose strategy.

Has infliximab influenced the course and prognosis of acute severe ulcerative colitis?

Ulcerative colitis (UC) still has no definitive cure since its etiology remains unclear. In recent years, considerable progress has been made with regard to our knowledge of the pathogenesis of UC. Advances in biotechnology have led to the development of biologic therapies which selectively target single key mediators or receptors involved in the pathogenesis of the disease - ie, tumor necrosis factor (TNF)-α, integrin, interleukins 12/23. Biologic therapies caused a revolution in the treatment of UC, providing specific options for patients refractory to conventional treatment. In recent years, antibodies anti-TNFα and anti-integrin have shown efficacy in improving the course and prognosis of ambulatory patients with moderate-to-severe UC. Nevertheless, whether biologics have brought so many benefits also for hospitalized patients with acute severe UC is still debated. Acute severe UC is a potentially life-threatening condition that affects up to 25% of patients during the course of their disease. It requires hospital admission due to the risk of complications and death, and it can necessitate urgent colectomy. Major adverse outcomes of acute severe UC are mortality and colectomy. The aim of this systematic review of the literature was to analyze the impact of biologics, in particular infliximab, on the course and prognosis of acute severe UC. Mortality and colectomy rates were considered as outcome measures.

The Use of Biologics in Patients with Inflammatory Bowel Disease and Primary Sclerosing Cholangitis

Purpose of Review

Biologics are well established in the treatment of many immuno-inflammatory diseases including inflammatory bowel disease (IBD). However, although primary sclerosing cholangitis (PSC) is closely associated with IBD, the role of biologics in PSC remains uncertain. Many new biologics are becoming available to treat IBD, and this review aims to use the experience of biologics in PSC so far to guide more effective evaluation of emerging therapies in the future.

Recent Findings

Antibodies to TNF-α were the first biologics used in IBD, and retrospective analysis suggests that they may have some benefit in PSC, even though an early randomised controlled trial (RCT) showed no effect. Mechanistic studies suggest that TNF-α may have a pathogenic role in PSC. An antibody to integrin α4β7 is effective in IBD, and there are emerging data on its effects in PSC, although no RCT data are available. Mechanistic studies suggest that interrupting the migration of lymphocytes is relevant in PSC. Two biologics, targeting vascular adhesion protein-1 (VAP-1), and lysyl oxidase-like 2 (LOXL2) have been tested in RCTs. The trial of anti-VAP1 is ongoing, whilst the anti-LOXL2 trial was negative.

Summary

Anti-TNF antibodies may benefit PSC when used to treat concomitant IBD, and this may be a direct effect on the liver in a subgroup of patients, or may be an indirect effect of treating IBD. Similarly, anti-integrin therapy may benefit a subset of patients with IBD and PSC. RCTs could decide the role of emerging biologics in PSC, although future trials should be guided by biomarkers that could predict response to the pathway being targeted.

Correlation Between Anti-TNF Serum Levels and Endoscopic Inflammation in Inflammatory Bowel Disease Patients

OBJECTIVES

(a) To evaluate the diagnostic accuracy of anti-TNF trough levels to predict mucosal healing in inflammatory bowel disease (IBD); (b) to determine the best cut-off point to predict mucosal healing in IBD patients treated with anti-TNF.

METHODS

This is a multicenter, prospective study. IBD patients under anti-TNF treatment for at least 6 months that had to undergo an endoscopy were included. Mucosal healing was defined as: Simple endoscopic score for Crohn's Disease < 3 for Crohn's disease (CD), Rutgeerts score < i2 for CD in postoperative setting, or Mayo endoscopic score ≤ 1 for ulcerative colitis (UC). Anti-TNF concentrations were measured using SMART ELISAs at trough.

RESULTS

A total of 182 patients were included. Anti-TNF trough levels were significantly higher among patients that had mucosal healing than among those who did not. The area under the curve of infliximab for mucosal healing was 0.63 (best cutoff value 3.4 μg/mL), and for adalimumab 0.60 (best cutoff value 7.2 μg/mL). In the multivariate analysis, having anti-TNF drug levels above the cutoff values [odds ratio (OR) 3.1]) and having UC instead of CD (OR 4) were associated with a higher probability of having mucosal healing. Additionally, the need for an escalated dosage (OR 0.2) and current smoking habit (OR 0.2) were also associated with a lower probability of mucosal healing.

CONCLUSIONS

There was an association between anti-TNF trough levels and mucosal healing in IBD patients; however, the accuracy of the determination of infliximab and adalimumab concentrations able to predict mucosal healing was suboptimal.

Optimal management of acute severe ulcerative colitis

Acute severe ulcerative colitis is a life-threatening medical emergency, which can be associated with significant morbidity and is preventable through prompt and effective management. Corticosteroids remain the cornerstone of initial therapy, although a third of patients will not respond. Further management hinges on timely decisions with use of rescue therapy with ciclosporin or infliximab, without compromising the health or safety of the patient, or timely surgery. Although such patients need specialist care, it is imperative that emergency care physicians are aware of the important principles of management of this condition to achieve successful outcomes. Risk stratification and the use of predictive models using clinical parameters have reduced the morbidity associated with this condition.We discuss current evidence and present a clinical approach to clinicians involved in the emergency care of patients with acute severe ulcerative colitis in this review.