Vedolizumab Drug Level Correlation With Clinical Remission, Biomarker Normalization, and Mucosal Healing in Inflammatory Bowel Disease

Therapeutic Drug Monitoring as a Tool for the Clinical Outcome Prediction in Vedolizumab-Treated Patients: An Italian Pilot Study

Over the years, vedolizumab (VDZ) has emerged as a more effective target therapy for inflammatory bowel disease. The aim of this work was to analyze a cohort of inflammatory bowel disease patients, evaluating the association between VDZ serum concentrations at 6 months from starting therapy and their clinical and biochemical indexes within one year of treatment, correlating drug levels with response and clinical remission. Forty patients treated with VDZ were enrolled. Drug concentrations were quantified through ELISA methods. VDZ levels correlated with hemoglobin levels at twelve months of therapy (p = 0.03) and with clinical remission at twelve months of therapy (p = 0.03); patients who reached clinical remission showed higher VDZ concentrations. A VDZ cut-off value of 43.1 μg/mL was suggested, predicting clinical remission at twelve months of therapy. A statistically significant association between VDZ levels at T6 and calprotectin <250 μg/g at T12 was found (p = 0.04). Furthermore, the optimal threshold value of VDZ levels at T6 associated with calprotectin <250 μg/g at T12 was identified: through levels higher than 45.2 µg/mL, we were able to predict remission one year after therapy. In the final regression multivariate model, no factor was retained as a predictor of clinical remission at one year of treatment. In conclusion, this is the first pilot study reporting a possible VDZ serum cut-off value able to predict not only the clinical remission at twelve months of therapy but also the calprotectin level, which is very important, as it is a surrogate marker of mucosal healing.

Proactive therapeutic drug monitoring and vedolizumab dose optimization in children with inflammatory bowel disease

OBJECTIVES

Therapeutic drug monitoring (TDM) and dose optimization have been shown to improve clinical outcomes with antitumor necrosis factor and recent studies in adults suggest an exposure-response relationship with drug levels associated with improved clinical outcomes. However, these levels are not universally recognized as therapeutic targets for vedolizumab dosing. We aimed to assess the impact of a TDM quality improvement (QI) initiative on 52-week clinical outcomes and describe proactively obtained vedolizumab levels during the induction period in children with inflammatory bowel disease (IBD).

METHODS

A QI initiative to proactively obtain TDM levels at Week 6 was implemented in 2019. A retrospective review of pediatric patients with IBD treated with vedolizumab from 2018 to 2022 was performed. Baseline demographic data, medication dosing details, disease characteristics, lab results, and 12-month clinical outcomes were recorded. For this study, we defined therapeutic target levels (>20 μg/mL at Week 6 and >12 μg/mL during maintenance) based on existing data correlating these levels with improved clinical outcomes.

RESULTS

Fifty-nine patients (31 Crohn disease [CD], 28 ulcerative colitis [UC]/indeterminate colitis [IC]) were included in the study. In total, 68% (40/59) of patients had vedolizumab levels at Week 6 and 90% (53/59) had levels drawn at Week 6 or 14. Thirty-five percent of Week 6 trough levels were below our defined target of 20 μg/mL. Fifty-two of 59 patients had available data at 52 weeks. Over 80% (42/52) of patients remained on vedolizumab 52 weeks after initiation (CD 79% [23/29], UC/IC 83% [19/23]). Sixty-two percent (26/42) of patients that remained on vedolizumab at 52 weeks were treated with an intensified dosing interval of <8 weeks. Thirty-one of these 42 (74%) were in clinical remission (CR) rate at 52 weeks with 29/42 (69%) in corticosteroid-free remission. The CR rate for the entire cohort including those who discontinued therapy due to a lack of efficacy before 52 weeks was 60% (31/52).

CONCLUSION

Proactive TDM and early dose optimization with vedolizumab may improve drug durability and clinical outcomes in pediatric patients with IBD.

Therapeutic Drug Monitoring for Biologic and Small-Molecule Therapies for Inflammatory Bowel Disease

Background: Inflammatory bowel disease (IBD), encompassing ulcerative colitis and Crohn's disease, necessitates long-term medical therapy to manage symptoms and prevent complications. Therapeutic drug monitoring (TDM) has emerged as a strategy to optimize treatment efficacy, particularly with anti-tumour necrosis factor (anti-TNF) alpha drugs. This review explores the role of TDM for non-anti-TNF advanced therapies in IBD, focusing on vedolizumab, ustekinumab, tofacitinib, upadacitinib, risankizumab and ozanimod. Methods: The literature search, conducted through OVID (Medline) and PubMed, delves into proactive versus reactive TDM, timing of monitoring and methods for measuring drug levels and anti-drug antibodies. Results: While ustekinumab and vedolizumab exhibit exposure-response relationships, consensus on target levels and the role of TDM adjustments remains elusive. Limited data on risankizumab suggest a dose-dependent response, while for small molecule therapies (janus kinase inhibitors and ozanimod), the absence of real-world data and commercially available TDM tools pose challenges. Conclusion: At present, with the available data, there is a limited role for TDM in non-anti-TNF biologic and small-molecule therapies. This review underscores the need for further research to delineate the utility of TDM in guiding treatment decisions for these agents.

Efficacy and Safety of Vedolizumab in Patients with Inflammatory Bowel Disease in Association with Vedolizumab Drug Levels

BACKGROUND

Vedolizumab (VDZ) is a well-established and important therapeutic option in the treatment of patients with inflammatory bowel disease (IBD). However, the significance of therapeutic drug monitoring (TDM) with VDZ remains a contradictory field in daily clinical practice. Our study aims to clarify the predictive impact of VDZ drug levels in long-term clinical outcomes in a real-world cohort.

METHODS

Patients with moderate to severe ulcerative colitis (UC) and Crohn's disease (CD) from a tertiary IBD referral center at the University Hospital Augsburg, Germany, were enrolled in this single-center retrospective data analysis. Clinical and endoscopic data were collected at month 6, month 12, and at the last time of follow-up, and outcomes were correlated with VDZ levels at week 6.

RESULTS

This study included 95 patients, 68.4% (n = 65) with UC, 24.2% (n = 23) with CD, and 7.4% (n = 7) with indeterminate colitis (CI). Patients with a mean VDZ treatment time of 17.83 months ± 14.56 showed clinical response in 29.5% (n = 28) and clinical remission in 45.3% (n = 43) at the end of the study. Endoscopic response occurred in 20.0% (n = 19) and endoscopic remission in 29.5% (n = 28) at the end of the study. The sustained beneficial effect of VDZ was also reflected in a significant change in biomarker levels. VDZ trough level at week 6 was determined in 48.4% (n = 46) with a mean of 41.79 µg/mL ± 24.58. A significant association between VDZ level at week 6 and both short and long-term outcomes could not be demonstrated. However, numerically higher VDZ levels were seen in patients with endoscopic and clinical improvement at month 6 and at the time of last follow-up.

CONCLUSIONS

This study demonstrated efficacy and safety for VDZ in a real-world cohort. Although, for some parameters, a clear trend for higher VDZ levels at week 6 was seen, the efficacy of VDZ was not significantly correlated to VDZ level at week 6, which questions the predictive value of VDZ levels in the real world.

Do Vedolizumab trough Levels Predict the Outcome of Subsequent Therapy in Inflammatory Bowel Disease?

Background: Vedolizumab trough serum levels have been associated with clinical and endoscopic response in patients with inflammatory bowel disease (IBD). A recent study demonstrated that higher trough levels before dose escalation are associated with favorable outcomes. Objectives: We aimed to identify whether vedolizumab trough levels predict outcome of subsequent therapy. Methods: This retrospective study included IBD patients consecutively receiving vedolizumab therapy between November 2014 and June 2021. Only patients with a loss of response (LOR) to vedolizumab and available trough drug levels prior to therapy cessation were included. Clinical and endoscopic scores were recorded at 6 and 12 months post switching therapy. Results: Overall, 86 IBD patients (51 Crohn's disease, 35 ulcerative colitis) who discontinued vedolizumab were included; of those, 72 (83.7%) were due to LOR. Upon vedolizumab discontinuation, 66.3% of patients were switched to another biologic therapy. Trough vedolizumab levels at discontinuation due to LOR did not differ between patients with clinical response and LOR regarding subsequent therapy at 6 months [median 33.8 μg/mL (IQR 13.2-51.6) versus 31.7 μg/mL (IQR 9.1-64.8), p = 0.9] and at 12 months [median 29.6 μg/mL (IQR 14.3-51.6) versus 34.1 μg/mL (IQR 12.2-64.7), p = 0.6]. Patients progressing to subsequent surgery had numerically lower vedolizumab trough levels at LOR compared with patients who were treated with an additional medical therapy (median 14.3, IQR 4-28.2 μg/mL versus 33.5, IQR 13-51.6 μg/mL, p = 0.08). Conclusions: Vedolizumab trough levels upon LOR do not predict response to subsequent medical therapy; however, lower drug levels may suggest a more aggressive disease pattern and future need for surgery.

Obesity and novel management of inflammatory bowel disease

Obesity is prevalent within the inflammatory bowel disease (IBD) population, particularly in newly developed countries. Several epidemiological studies have suggested that 15%-40% of IBD patients are obese, and there is a potential role of obesity in the pathogenesis of IBD. The dysfunction of mesenteric fat worsens the inflammatory course of Crohn’s disease and may induce formation of strictures or fistulas. Furthermore, obesity may affect the disease course or treatment response of IBD. Given the increasing data supporting the pathophysiologic and epidemiologic relationship between obesity and IBD, obesity control is being suggested as a novel management for IBD. Therefore, this review aimed to describe the influence of obesity on the outcomes of IBD treatment and to present the current status of pharmacologic or surgical anti-obesity treatments in IBD patients.

Therapeutic Drug Monitoring of Vedolizumab in Inflammatory Bowel Disease Patients during Maintenance Treatment—TUMMY Study

There are limited data on therapeutic drug monitoring (TDM) in inflammatory bowel disease (IBD) patients treated with vedolizumab (VDZ). Although an exposure–response relation has been demonstrated in the post-induction phase, this relationship is more uncertain in the maintenance phase of treatment. The aim of our study was to determine whether there is an association between VDZ trough concentration and clinical and biochemical remission in the maintenance phase. A prospective, observational multicenter study has been performed on patients with IBD on VDZ in the maintenance treatment (≥14 weeks). Patient demographics, biomarkers, and VDZ serum trough concentrations were collected. Clinical disease activity was scored by the Harvey Bradshaw Index (HBI) for Crohn’s disease (CD) and the Simple Clinical Colitis Activity Index (SCCAI) for ulcerative colitis (UC). Clinical remission was determined as HBI < 5 and SCCAI < 3. Biochemical remission was defined as fecal calprotectin <250 mg/kg and serum CRP <5 mg/L. A total of 159 patients (59 CD, 100 UC) were included. In none of the patient groups, a statistically significant correlation between trough VDZ concentration and clinical remission was observed. Patients in biochemical remission had higher VDZ trough concentrations (p = 0.019). In this population, higher trough VDZ concentrations were associated with biochemical remission but not with clinical remission.

Impact of tumor necrosis factor antagonist combination and anti-integrin therapies on body mass index in inflammatory bowel disease: A cross-sectional study

Background

The impact of biologic therapies on body mass index (BMI) in patients with inflammatory bowel disease (IBD) is unclear. This study investigates any associations between BMI, type of IBD, and the type of medications taken among patients with IBD with varying weight categories.

Methods

A cross sectional study was performed in an IBD tertiary care center. Data was obtained from patients with IBD attending outpatient clinics from January 1st, 2021 until November 1st, 2021. Adult patients, older than 18 years, with a diagnosis of Crohn's disease (CD) or ulcerative colitis (UC) were recruited. The primary outcome was the association between BMI and medication used in IBD. The secondary outcome was the association between BMI and disease type and location in patients with IBD.

Results

The study included a total of 528 patients of which, 66.5% have CD. Patients with normal weight comprises 55.9% of the participants, while those who are underweight, overweight or obese are 3.4, 28.2, and 12.5%, respectively. None of the underweight patients had UC. Among the normal weight, overweight and obese BMI categories, 34.6% vs. 36.2% vs. 31.8% had UC, respectively. Patients who are on tumor necrosis factor inhibitors (anti-TNF) with an immunomodulator (anti-TNF combination), are more likely to be overweight or obese than patients who are not on anti-TNF combination (OR 2.86, 95% CI 1.739-4.711, p < 0.001). Patients on vedolizumab are twice as likely to be overweight or obese than patients not on vedolizumab (OR 2.23, 95% CI 1.086-4.584, p < 0.05). Patients with ileocolonic CD are more likely to be overweight or obese compared to other subtypes of CD (OR 1.78, 95% CI 1.14-2.77, p = 0.01).

Conclusion

Many patients with IBD are either obese or overweight. Patients with IBD who are on anti-TNF combination therapy or vedolizumab monotherapy are more likely to be obese and overweight. In addition, patients will ileocolonic CD are more likely to be obese or overweight.

Residual homing of α4β7-expressing β1+PI16+ regulatory T cells with potent suppressive activity correlates with exposure-efficacy of vedolizumab

OBJECTIVE

The anti-α4β7 integrin antibody vedolizumab is administered at a fixed dose for the treatment of IBDs. This leads to a wide range of serum concentrations in patients and previous studies had suggested that highest exposure levels are associated with suboptimal clinical response. We aimed to determine the mechanisms underlying these non-linear exposure-efficacy characteristics of vedolizumab.

DESIGN

We characterised over 500 samples from more than 300 subjects. We studied the binding of vedolizumab to T cells and investigated the functional consequences for dynamic adhesion, transmigration, gut homing and free binding sites in vivo. Employing single-cell RNA sequencing, we characterised α4β7 integrin-expressing T cell populations 'resistant' to vedolizumab and validated our findings in vitro and in samples from vedolizumab-treated patients with IBD. We also correlated our findings with a post-hoc analysis of the Gemini II and III studies.

RESULTS

Regulatory T (T_Reg) cells exhibited a right-shifted vedolizumab binding profile compared with effector T (T_Eff) cells. Consistently, in a certain concentration range, the residual adhesion, transmigration, homing of and availability of functional α4β7 on T_Reg cells in vivo was higher than that of/on T_Eff cells. We identified a vedolizumab-'resistant' α4β7-expressing β1⁺PI16⁺ T_Reg cell subset with pronounced regulatory properties as the substrate for this effect. Our observations correlated with exposure-efficacy data from Gemini II and III trials.

CONCLUSION

Completely blocking T_Eff cell trafficking with vedolizumab, while simultaneously permitting residual homing of powerful T_Reg cells in an optimal 'therapeutic window' based on target exposure levels might be a strategy to optimise treatment outcomes in patients with IBD.

Real-world multicentre observational study including population pharmacokinetic modelling to evaluate the exposure-response relationship of vedolizumab in inflammatory bowel disease: ERELATE Study

BACKGROUND

ERELATE was a phase 4, multinational, retrospective, observational study.

AIM

To evaluate the relationship between intravenous vedolizumab exposure and treatment outcomes over 52 weeks in adults with ulcerative colitis (UC) or Crohn's disease (CD).

METHODS

Real-world data from patients with UC or CD treated with intravenous vedolizumab in nine centres in six countries were collected retrospectively. Treatment outcomes were collected at Weeks 14, 26 and 52. An established population pharmacokinetic model (incorporating observed vedolizumab concentrations based on a Bayesian approach) was used to predict individual vedolizumab exposure. Vedolizumab exposure-response relationship was evaluated overall, by indication and based on baseline characteristics.

RESULTS

The study population (n = 695; UC, n = 304; CD, n = 391) had a median age of 39 years; 47.9% were male and 86.9% had prior tumour necrosis factor antagonist exposure. By Week 14, clinical, endoscopic, deep (clinical plus endoscopic) and biologic remission was achieved by 47.3%, 59.6%, 30.7% and 19.0% of patients respectively. Higher vedolizumab trough concentration early in treatment was consistently associated with clinical remission at later time points. Clinical remission at Week 14 and Week 52 was associated with Week 6 trough concentrations of ≥31.0 and ≥32.0 μg/ml respectively. Importantly, multivariable analysis identified baseline clearance as the only exposure measure predictive of clinical and deep remission at Week 52.

CONCLUSIONS

In this real-world study, a positive exposure-response relationship was observed for vedolizumab. Vedolizumab concentration during induction may be an important predictor of short- and long-term outcomes, and similarly, vedolizumab baseline clearance may be an important predictor of remission.

Updates in therapeutic drug monitoring in inflammatory bowel disease

Biologics and immunomodulators (IMM) are generally considered the most effective therapies for the treatment of ulcerative colitis and Crohn’s disease. However, despite the efficacy of these therapies, many patients either have a primary lack of response or a secondary loss of response to these medications. Therapeutic drug monitoring (TDM) is a systematic approach to managing such patients. In this review, we summarize the latest data on TDM, including reactive and proactive TDM, in patients with inflammatory bowel disease on biologics and/or IMM.

Limited Dose-Dependent Effects of Vedolizumab on Various Leukocyte Subsets

OBJECTIVES

The anti-α4β7 integrin antibody vedolizumab (VDZ) is successfully used for the treatment of inflammatory bowel diseases. However, only a subgroup of patients respond to therapy. VDZ is administered at a fixed dose, leading to a wide range of serum concentrations in patients. Previous work from our group showed a dose-dependent preferential binding of VDZ to effector compared with regulatory CD4 + T cells. Therefore, we aimed to determine the dose-dependent binding profile of VDZ to other leukocyte subsets.

METHODS

We characterized α4β7 integrin expression on CD8 + T cells, CD19 + B cells, CD14 + monocytes, natural killer cells, and eosinophils from patients with inflammatory bowel disease and healthy controls. We studied the binding of VDZ to these cells at different concentrations and investigated the functional consequences for dynamic adhesion and transmigration in vitro .

RESULTS

The expression of α4β7 differed between the analyzed leukocyte subsets and was significantly higher on eosinophils from inflammatory bowel disease patients compared with controls. Almost all α4β7-expressing cells from these subsets were bound by VDZ at a concentration of 10 μg/mL. Dynamic cell adhesion was significantly impaired in all subsets, but there were no dose-dependent differences in the inhibition of adhesion.

DISCUSSION

Our data suggest that α4β7-expressing CD8 + T cells, CD19 + B cells, CD14 + monocytes, natural killer cells, and eosinophils are a target of VDZ. However, there do not seem to be concentration-dependent differences, regarding the effects on these cells in the clinically relevant range. Thus, the reported exposure-efficacy characteristic of VDZ can probably mainly be attributed to CD4 + T-cell subsets.

A Comprehensive Literature Review and Expert Consensus Statement on Therapeutic Drug Monitoring of Biologics in Inflammatory Bowel Disease

Therapeutic drug monitoring (TDM) of biologics is a rapidly evolving field. We aimed to provide a consensus statement regarding the clinical utility of TDM for biologics in inflammatory bowel disease (IBD). A modified Delphi method was applied to develop consensus statements. A comprehensive literature review was performed regarding TDM of biologic therapies in IBD, and 45 statements were subsequently formulated on the potential application of TDM in IBD. The statements, along with literature, were then presented to a panel of 10 gastroenterologists with expertise in IBD and TDM who anonymously rated them on a scale of 1-10 (1 = strongly disagree and 10 = strongly agree). An expert consensus development meeting was held virtually to review, discuss, refine, and reformulate statements that did not meet criteria for agreement or that were ambiguous. During the meeting, additional statements were proposed. Panelists then confidentially revoted, and statements rated ≥7 by 80% or more of the participants were accepted. During the virtual meeting, 8 statements were reworded, 7 new statements were proposed, and 19 statements were rerated. Consensus was finally reached in 48/49 statements. The panel agreed that reactive TDM should be used for all biologics for both primary nonresponse and secondary loss of response. It was recommended that treatment discontinuation should not be considered for infliximab or adalimumab until a drug concentration of at least 10-15 μg/mL was achieved. Consensus was also achieved regarding the utility of proactive TDM for anti-tumor necrosis factor therapy. It was recommended to perform proactive TDM after induction and at least once during maintenance. Consensus was achieved in most cases regarding the utility of TDM of biologics in IBD, specifically for reactive and proactive TDM of anti-tumor necrosis factors.

Certolizumab Trough Levels and Antibodies in Crohn Disease: A Single-Center Experience

Background

Certolizumab pegol (CZP) has been successfully used for the treatment of Crohn disease (CD); however, real-world data regarding the utility of CZP trough levels (CTLs) are lacking. We aimed to correlate CTL with CD outcomes and to determine frequency of CZP antibodies.

Methods

Retrospective evaluation of all CD patients on maintenance CZP with CTL obtained between 2016 and 2019. Outcomes included: median CTL, presence of anti-CZP antibodies, biochemical response (BR), clinical response (CR), radiologic response (RR), radiologic healing (RH), and mucosal healing (MH).

Results

Seventy-seven CD patients were included. Median CTL was 18.9 µg/mL (interquartile range, 7.6-35.4). Twenty-three patients (27.3%) had positive antibody levels, with lower median CTL compared to patients with no antibodies (0.0 vs 29.8; P < 0.0001). Median CTL levels were higher in patients with vs without CR (30.4 vs 10.3 µg/mL; P = 0.0015) and RR (29.6 vs 5.8 µg/mL; P = 0.006). CZP dosing at least every 2 weeks was associated with higher odds of achieving MH (odds ratio, 3.2; 95% confidence interval, 1.03-9.97). CTL resulted in change in clinical management in 62.7% of cases and presence of CMZ antibodies was associated with an odds ratio of 5.83 (95% confidence interval, 1.57-21.73) of change in management. Receiver operating characteristic curve and quartile analysis suggested that CTL >19 µg/mL is associated with increased rates of CR and RR.

Conclusions

Higher CTL was significantly associated with CR and RR. The rate of CZP antibodies was 27.3%. Our data suggest maintenance CTL of ≥19 µg/mL should be achieved in order to optimize outcomes in clinical practice.

Therapeutic Drug Monitoring for Current and Investigational Inflammatory Bowel Disease Treatments

This article reviews therapeutic drug monitoring (TDM) use for current inflammatory bowel disease (IBD) treatments. IBD comprises Crohn's disease and ulcerative colitis-chronic gastrointestinal inflammatory disorders. Treatment options for moderate to severe IBD include thiopurines; methotrexate; biologic agents targeting tumor necrosis factor, α4β7 integrin or interleukins 12 and 23; and Janus kinase inhibitors. TDM is recommended to guide treatment decisions for some of these agents. Published literature concerning TDM for IBD treatments was reviewed. S.D.L., R.S., and E.V.L. drew on their clinical experiences. Polymorphisms resulting in altered enzymatic activity inactivating thiopurine metabolites can lead to myelotoxicity and hepatotoxicity. Increased elimination of biologic agents can result from immunogenicity or higher disease activity, leading to low drug concentration and consequent nonresponse or loss of response. TDM may aid treatment and dose decisions for individual patients, based on monitoring metabolite levels for thiopurines, or serum drug trough concentration and antidrug antibody levels for biologic agents. Challenges remain around TDM implementation in IBD, including the lack of uniform assay methods and guidance for interpreting results. The Janus kinase inhibitor tofacitinib is not impacted by enzyme polymorphisms or disease activity, and is not expected to stimulate the formation of neutralizing antidrug antibodies. TDM is associated with implementation challenges, despite the recommendation of its use for guiding many IBD treatments. Newer small molecules with less susceptibility to patient variability factors may fulfill the unmet need of treatment options that do not require TDM, although further study is required to confirm this.

Monitoring vedolizumab and ustekinumab drug levels in patients with inflammatory bowel disease: hype or hope?

Therapeutic drug monitoring (TDM) plays a vital role in implementing precision medicine in inflammatory bowel disease (IBD), and may contribute to increased effectiveness, lower rates of drug toxicity and cost savings. While expert panels advocate the use of reactive TDM for anti-tumor necrosis factor (anti-TNF) agents, TDM is not yet widely recommended for non-anti TNF biologicals. We provide an overview of the observational evidence of the value of TDM in case of vedolizumab and ustekinumab. We also shed light on obstacles that need to be addressed before establishing wide acceptance of TDM in the field of IBD. In this respect, new analytical techniques and modelling approaches are being developed to further optimize efficacy of TDM and to facilitate general acceptance of this tool in personalizing IBD management.

The Medical Management of Paediatric Crohn's Disease: an ECCO-ESPGHAN Guideline Update

OBJECTIVE

We aimed to provide an evidence-supported update of the ECCO-ESPGHAN guideline on the medical management of paediatric Crohn's disease [CD].

METHODS

We formed 10 working groups and formulated 17 PICO-structured clinical questions [Patients, Intervention, Comparator, and Outcome]. A systematic literature search from January 1, 1991 to March 19, 2019 was conducted by a medical librarian using MEDLINE, EMBASE, and Cochrane Central databases. A shortlist of 30 provisional statements were further refined during a consensus meeting in Barcelona in October 2019 and subjected to a vote. In total 22 statements reached ≥ 80% agreement and were retained.

RESULTS

We established that it was key to identify patients at high risk of a complicated disease course at the earliest opportunity, to reduce bowel damage. Patients with perianal disease, stricturing or penetrating behaviour, or severe growth retardation should be considered for up-front anti-tumour necrosis factor [TNF] agents in combination with an immunomodulator. Therapeutic drug monitoring to guide treatment changes is recommended over empirically escalating anti-TNF dose or switching therapies. Patients with low-risk luminal CD should be induced with exclusive enteral nutrition [EEN], or with corticosteroids when EEN is not an option, and require immunomodulator-based maintenance therapy. Favourable outcomes rely on close monitoring of treatment response, with timely adjustments in therapy when treatment targets are not met. Serial faecal calprotectin measurements or small bowel imaging [ultrasound or magnetic resonance enterography] are more reliable markers of treatment response than clinical scores alone.

CONCLUSIONS

We present state-of-the-art guidance on the medical treatment and long-term management of children and adolescents with CD.

Vedolizumab Trough Levels in Children With Anti-Tumor Necrosis Factor Refractory Inflammatory Bowel Disease

OBJECTIVES

Inflammatory bowel disease (IBD) can be successfully treated with vedolizumab. Studies in adult IBD patients have shown that differences in response to vedolizumab may be related to variability in vedolizumab trough levels, but in children with pediatric-onset IBD data regarding vedolizumab trough levels are not available. Thus far, the role of trough levels in pediatric-onset IBD treatment remains unclear. We aimed to investigate predictors of vedolizumab trough levels in pediatric-onset IBD patients.

METHODS

Data from anti-tumor necrosis factor refractory pediatric-onset IBD patients who received vedolizumab were collected retrospectively. Vedolizumab trough levels were measured in serum samples collected before each infusion. A linear mixed model was conducted to analyze factors that influence trough levels.

RESULTS

Twenty-six pediatric-onset IBD patients (14 ulcerative colitis [UC]), 9 Crohn Disease [CD], 3 IBD-unclassified [IBD-U]) received 258 vedolizumab infusions. Mean vedolizumab trough level at week 6 was 29.9 μg/mL (SD 17.8), and 11.5 μg/mL (SD 4.9) during maintenance therapy. CD patients had significantly lower trough levels than IBD-U patients (β 15.2; 95% confidence interval [CI] -1.1 to 29.2; P = 0.036). Higher fecal calprotectin (β -0.009; 95% CI -0.02 to -0.003; P = 0.007) and C-reactive protein levels (β -0.4; 95% CI -0.72 to -0.04; P = 0.027) were associated with lower trough levels, whereas shortening of time between infusions led to higher trough levels (β -0.77; 95% CI -0.9 to 0.64; P < 0.001).

CONCLUSIONS

In this group of pediatric-onset IBD patients, trough levels were significantly lower in CD patients compared with UC/IBD-U patients. Higher levels of inflammatory markers were associated with lower vedolizumab trough levels.

Higher vedolizumab serum levels do not increase the risk of adverse events in patients with inflammatory bowel disease

Background: Although its mechanism of action may confer a safety benefit, vedolizumab has still been associated with adverse events (AE). We investigated whether inflammatory bowel disease (IBD) patients with higher trough vedolizumab serum levels experienced an increased risk of AEs.Methods: This was a retrospective study of 76 IBD patients with at least one measurement of serum vedolizumab available. Vedolizumab levels ranged from <3.5 mcg/mL to 87.2 mcg/mL (median = 15.8 mcg/mL). The primary outcome was the rate of overall AEs. Secondary outcomes included the rates of infections, dermatologic reactions, infusion reactions, and other AEs. Multivariate logistic regression analysis was performed to evaluate the relationship between serum vedolizumab levels and AEs.Results: 19 patients out of 76 reported AEs. In patients with higher vedolizumab levels, there were 10 AEs reported out of 38 patients, which was not significantly different from the 9 AEs reported in 38 patients with lower vedolizumab levels (26.3% vs. 23.7%, p = .79). After adjustment for potential covariates, IBD patients with higher vedolizumab levels did not have higher odds of an AE than patients with lower levels (OR 0.92, 95% CI 0.30-2.81). Longer duration of therapy had higher odds of AEs, (OR of 1.04 at 95% CI 1.00-1.09, p = .0494 per additional month). None of the other variables were associated with a greater risk of AEs.Conclusions: There does not appear to be an increased risk of adverse events in IBD patients with higher vedolizumab levels, but duration of therapy may increase the risk of AEs.

Vedolizumab quantitation using high-resolution accurate mass-mass spectrometry middle-up protein subunit: method validation

Background While quantitation methods for small-molecule and tryptic peptide bottom-up mass spectrometry (MS) have been well defined, quantitation methods for top-down or middle-up MS approaches have not been as well defined. Therapeutic monoclonal antibodies (t-mAbs) are a group of proteins that can be used to both demonstrate the advantages of top-down or middle-up detection methods over classic tryptic peptide bottom-up along with the growing need for robust quantitation strategies/software for these top-down or middle-up methods. Bottom-up proteolytic digest methods for the t-mAbs tend to suffer from challenges such as limited peptide selection due to potential interference from the polyclonal immunoglobulin background, complicated workflows, and inadequate sensitivity and specificity without laborious purification steps, and therefore have prompted the search for new detection and quantitation methods. Time-of-flight along with Orbitrap MS have recently evolved from the research and/or pharmaceutical setting into the clinical laboratory. With their superior mass measurement accuracy, resolution and scanning speeds, these are ideal platforms for top-down or middle-up characterization and quantitation. Methods We demonstrate a validated, robust, middle-up protein subunit detection and quantitation method for the IgG1 t-mAb, vedolizumab (VEDO), which takes advantage of the high resolution of the Orbitrap MS detection and quantitation software to increase specificity. Results Validated performance characteristics met pre-defined acceptance criteria with simple workflows and rapid turnaround times: characteristics necessary for implementation into a high-volume clinical MS laboratory. Conclusions While the extraction method can easily be used with other IgG1 t-mAbs, the detection and quantitation method may become an option for measurement of other proteins.

Vedolizumab in the Treatment of Ulcerative Colitis: An Evidence-Based Review of Safety, Efficacy, and Place of Therapy

INTRODUCTION

Selective blockade of the integrins and mucosal adhesion molecules is a promising therapeutic strategy for ulcerative colitis (UC). Vedolizumab (VDZ), a humanized IgG1 monoclonal antibody against α4β7 integrin, selectively blocks the trafficking of the leukocytes into the gastrointestinal tract through its binding with the α4β7 integrin.

AIM

In this review, we provide an overview of the unique mechanism of VDZ, along with its efficacy, safety, and pharmacokinetic and pharmacodynamic data obtained from clinical trials, observational studies, and meta-analyses.

EVIDENCE REVIEW

A positive exposure-efficacy relationship with regard to clinical remission and clinical response was apparent in VDZ induction therapy. No drug-specific safety signals are currently available.

PLACE IN THERAPY

VDZ has been shown to be effective as first- or second-line induction and maintenance therapy in UC.

CONCLUSION

VDZ is a safe and effective treatment option for patients with UC. Prolonged VDZ induction therapy may contribute to improved outcomes in patients with UC, particularly those previously treated with tumor necrosis factor-α. Prospective head-to-head study of VDZ and other biologics would alter the positioning of VDZ much more clearly.

Vedolizumab Efficacy, Safety, and Pharmacokinetics With Reduced Frequency of Dosing From Every 4 Weeks to Every 8 Weeks in Patients With Crohn's Disease or Ulcerative Colitis

BACKGROUND AND AIMS

Vedolizumab was shown to be safe and effective for the treatment of Crohn's disease [CD] and ulcerative colitis [UC] in the GEMINI Long-Term Safety [LTS] study. The vedolizumab Extended Access Program [XAP] provides patients with continued treatment. This XAP pharmacokinetics [PK] sub-study investigated vedolizumab efficacy, safety, and PK.

METHODS

Vedolizumab dosing frequency was reduced from every 4 weeks [Q4W] to every 8 weeks [Q8W] at XAP enrolment, and patients were followed for 56 weeks. Outcomes included: efficacy, loss of clinical benefit, and re-escalation to Q4W dosing; and vedolizumab PK, immunogenicity, and adverse events.

RESULTS

Among 167 enrolled patients [CD = 88, UC = 79], 80 [91%] with CD and 73 [92%] with UC completed 56 weeks; 76 [86%] and 71 [90%] with CD and UC, respectively, remained on Q8W dosing for 56 weeks. Clinical remission, corticosteroid-free clinical remission, and C-reactive protein levels were stable among patients remaining on Q8W through Week 56. Four patients with CD and two with UC resumed Q4W dosing [three with CD regained clinical response]. Patients with CD who completed Week 56 on Q8W dosing had median trough vedolizumab concentrations of 43.6 µg/mL at enrolment and 10.4 µg/mL at Week 56; concentrations were 42.4 µg/mL and 13.3 µg/mL, respectively, in patients with UC. Treatment-related adverse events were infrequent; no new or serious adverse events related to vedolizumab were reported.

CONCLUSIONS

In the XAP-PK sub-study, adherence to Q8W dosing was high, with no loss of efficacy; very few patients required re-escalation to Q4W. There were no new safety signals.

Extent of Mucosal Inflammation in Ulcerative Colitis Influences the Clinical Remission Induced by Vedolizumab

Randomized controlled clinical trials and real-life observations indicate that less than 50% of patients with Crohn’s disease (CD) or ulcerative colitis (UC) respond to vedolizumab, a humanized monoclonal antibody that blocks the α4β7 integrin. Since α4β7-expressing lymphocytes mainly infiltrate the left colon, we assessed whether localization of CD and UC influences vedolizumab-induced remission. One hundred and eighty-one patients (74 CD and 107 UC) receiving vedolizumab in 3 referral centers were retrospectively evaluated for clinical remission at week 14. Demographic and clinical characteristics were compared between remitters and non-responders, and multivariable multinomial analysis was performed to identify predictors of remission. Remission was achieved in 17 CD (23%) and 34 UC (32%) patients, respectively. In CD, localization of the lesions did not influence clinical remission. In UC, the remitters had more frequently a distal/left-sided colitis (21/34, 62%) as compared to the non-responders (9/47, 19%), and extensive colitis was more frequent in the non-responders (38/47, 81%) than in the remitters (13/34, 38%). The multivariable multinomial analysis showed that distal/left-sided colitis was associated with a higher probability of clinical remission while extensive colitis was inversely associated with induction of remission. Data indicate that UC patients with distal or left-sided colitis are more likely to achieve remission than patients with extensive colitis following vedolizumab treatment.

Distinct Cutoff Values of Adalimumab Trough Levels Are Associated With Different Therapeutic Outcomes in Patients With Inflammatory Bowel Disease

Background and Aims

We aimed to evaluate the relationship of serum adalimumab trough levels (ATL) with disease activity of inflammatory bowel disease (IBD) patients in a large, well-characterized referral center-based cohort.

Methods

We compared serum ATL between those with clinical, biochemical, or endoscopic/radiologic disease activity and those without.

Results

A total of 236 patients with IBD were included. Higher cutoff levels were associated with endoscopic and/or radiologic responses (cutoff value: 5.3 mcg/mL, P = 0.003) compared with improvement in C-reactive protein (cutoff value: 4.3 mcg/mL, P = 0.031).

Conclusions

Higher cutoff ATL was associated with endoscopic and/or radiologic response.

Therapeutic drug monitoring with vedolizumab in inflammatory bowel disease

Therapeutic drug monitoring (TDM) is a useful tool for decision-making process in patients with inflammatory bowel disease (IBD) treated with anti TNF-α drugs, especially when experiencing loss of response. Growing evidences support the existence of exposure-response relationship with vedolizumab, but the utility and the appropriate use of TDM in clinical practice is still under debate. In this review, we summarize all evidences supporting a TDM-guided approach for patients treated with vedolizumab, suggesting three potential scenarios: 1) early prediction of long-term outcomes; 2) verifying the best strategy in case of loss of response; 3) maximizing therapeutic efficacy during maintenance treatment. Vedolizumab through concentrations <20 µg/mL at week 6 and >12 µg/mL seem to be associated with more favorable outcomes. No comparative studies have been conducted so far to demonstrate the advantage of adopting a TDM-guided versus an empirical approach for managing primary or secondary nonresponses. The frequency of antibodies to vedolizumab detection is quite low (up to 4% in pivotal trials), suggesting, unlike of anti TNF-α agents, a low probability of experiencing an immune-mediated pharmacokinetic failure in clinical practice. Future prospective and controlled studies are warranted to establish the guidance on the use of a TDM-guided approach with vedolizumab in clinical practice.

Systematic review with meta-analysis: association between vedolizumab trough concentration and clinical outcomes in patients with inflammatory bowel diseases

BACKGROUND

There has been limited evaluation of the association between vedolizumab trough concentration and clinical outcomes in patients with inflammatory bowel diseases (IBD).

AIM

To perform a systematic review and meta-analysis to evaluate the potential role of therapeutic drug monitoring (TDM) for vedolizumab.

METHODS

Through a systematic literature search through 28 February 2019, we identified five cohort studies (558 patients, 42% with ulcerative colitis) reporting the association between vedolizumab trough concentration and clinical outcomes in patients with IBD. We calculated mean difference (MD) in vedolizumab trough concentration in patients achieving vs not achieving clinical outcomes, and qualitatively synthesized thresholds associated with favourable outcomes.

RESULTS

In patients with UC, median vedolizumab trough concentrations were consistently higher in patients achieving clinical remission (median, 14.3 μg/mL vs 10.5 μg/mL; MD, 5.1 μg/mL, 95% CI, 2.8-7.4) or endoscopic remission (median, 13.0 μg/mL vs 9.7; MD, 5.1 μg/mL, 95% CI, 2.2-7.9). In patients with CD, there was no significant difference in median vedolizumab trough concentrations in patients achieving vs not achieving clinical remission (MD, 2.0 μg/mL; 95% CI, -0.5 to 4.5) or endoscopic remission (MD, 3.6 μg/mL; 95% CI, -1.4 to 8.6). In patients with UC, week 6 vedolizumab trough concentrations ≥18.5-20.8 μg/mL, and maintenance trough concentrations ≥9.0-12.6 μg/mL were associated with favourable clinical outcomes. Antibodies to vedolizumab were reported in 1.7%-3.0% patients on maintenance therapy.

CONCLUSION

Based on meta-analysis, patients with UC who achieve endoscopic and clinical remission have significantly higher vedolizumab trough concentration during maintenance therapy. Vedolizumab trough concentration >20 μg/mL at week 6, and >12 μg/mL during maintenance may be associated with better outcomes, though cause-effect relationship remains unclear. Prospective studies on reactive and proactive therapeutic drug monitoring of vedolizumab (vs empiric dose escalation) are warranted.

Achieving Mucosal Healing in Inflammatory Bowel Diseases: Which Drug Concentrations Need to Be Targeted?

Biologicals introduced a major shift in the treatment of patients suffering from inflammatory bowel diseases. Despite providing a tight disease control for many patients, a considerable proportion of patients will fail to respond favorably to treatment or will lose response over time. Therapeutic drug monitoring emerged as a valuable tool to guide clinical decision making as serum drug concentrations have been linked to outcomes. Focusing on mucosal healing as the ultimate treatment goal, different drug concentration thresholds to achieve this outcome have been identified in the literature and are summarized in this review. For therapeutic drug monitoring to be successful in guiding clinical decision making, the used assay, the sampling time point, and the outcome that is aimed for should be taken into account when interpreting drug concentration thresholds. Awareness of these essential aspects among clinicians will improve the implementation of therapeutic drug monitoring and aid in making an evidence‐based decision.

Appropriate Therapeutic Drug Monitoring of Biologic Agents for Patients With Inflammatory Bowel Diseases

BACKGROUND & AIMS

Therapeutic drug monitoring (TDM) is widely available for biologic therapies in patients with inflammatory bowel disease (IBD). We reviewed current data and provided expert opinion regarding the clinical utility of TDM for biologic therapies in IBD.

METHODS

We used a modified Delphi method to establish consensus. A comprehensive literature review was performed regarding the use of TDM of biologic therapy in IBD and presented to international IBD specialists. Subsequently, 28 statements on the application of TDM in clinical practice were rated on a scale of 1 to 10 (1 = strongly disagree and 10 = strongly agree) by each of the panellists. Statements were accepted if 80% or more of the participants agreed with a score ≥7. The remaining statements were discussed and revised based on the available evidence followed by a second round of voting.

RESULTS

The panel agreed on 24 (86%) statements. For anti-tumor necrosis factor (anti-TNF) therapies, proactive TDM was found to be appropriate after induction and at least once during maintenance therapy, but this was not the case for the other biologics. Reactive TDM was appropriate for all agents both for primary non-response and secondary loss of response. The panellists also agreed on several statements regarding TDM and appropriate drug and anti-drug antibody (ADA) concentration thresholds for biologics in specific clinical scenarios.

CONCLUSION

Consensus was achieved towards the utility of TDM of biologics in IBD, particularly anti-TNF therapies. More data are needed especially on non-anti-TNF biologics to further define optimal drug concentration and ADA thresholds as these can vary depending on the therapeutic outcomes assessed.

The Evolving Role of Thiopurines in Inflammatory Bowel Disease

PURPOSE OF REVIEW

With the advent of biologic therapies for the treatment of inflammatory bowel disease, the roles of thiopurines have continued to evolve. This review will focus on recent advances in pharmacology and the safety and efficacy of thiopurines as maintenance therapies for steroid-induced remissions and post-surgical maintenance of remission and as combination therapies to reduce immunogenicities of biologic agents.

RECENT FINDINGS

Due to pharmacogenetics of thiopurine S-methyltransferase, thiopurine dosing is more effectively based on monitoring of thiopurine metabolites rather than weight-based dosing. Thiopurines continue to have a role as maintenance therapy after steroid-induced remissions and in combination with biologics to induce and maintain remission. Safety monitoring includes measurements of blood counts, liver chemistries, and dermatologic evaluations and protection from sun exposure. Thiopurines appear to be safe during pregnancies and while very uncommon, lymphomas (including hepatosplenic T cell lymphomas) remain a recognized risk, particularly in younger and older males.

Association of trough vedolizumab levels with clinical, biological and endoscopic outcomes during maintenance therapy in inflammatory bowel disease

OBJECTIVE

To establish the relationship between trough vedolizumab levels and outcomes during maintenance therapy.

DESIGN

Cross-sectional service evaluation was performed on patients with inflammatory bowel disease (IBD) receiving maintenance vedolizumab therapy (minimum of 12 weeks following induction). Prior to infusion, data on clinical activity (Harvey-Bradshaw Index or partial Mayo score), trough C-reactive protein (CRP)/vedolizumab levels and faecal calprotectin were collected. Endoscopic data (±8 weeks from vedolizumab level testing) were obtained by review of medical records. Vedolizumab levels were processed using the Immundiagnostik monitor ELISA.

SETTING

The Edinburgh IBD Unit, Western General Hospital (tertiary IBD referral centre).

PATIENTS

Seventy-three patients (30 ulcerative colitis and 43 Crohn's disease) were identified who fulfilled inclusion criteria and had vedolizumab levels matched with clinical activity scores, CRP and faecal calprotectin. Of these, 40 patients also had matched endoscopic data.

MAIN OUTCOME MEASURES

The association of trough vedolizumab levels with clinical remission (Harvey-Bradshaw Index <5 or partial Mayo <2), biologic remission (faecal calprotectin <250 µg/g+CRP <5 mg/L) and endoscopic remission (Mayo score 0/no inflammation and ulceration on colonoscopy).

RESULTS

The median trough vedolizumab levels were similar between patients in and not in clinical remission (10.6 vs 9.9 µg/mL, p=0.54); biologic remission (10.6 vs 9.8 µg/mL, p=0.35) and endoscopic remission (8.1 vs 10.2 µg/mL, p=0.21). Quartile analysis revealed no significant increase in the proportion of patients in clinical remission, biologic remission or endoscopic remission with increasing trough vedolizumab levels (p<0.05).

CONCLUSIONS

In this cohort, trough vedolizumab levels were not associated with clinical, biological or endoscopic outcomes during maintenance therapy.

Therapeutic drug monitoring in inflammatory bowel disease: for every patient and every drug?

PURPOSE OF REVIEW

The current review provides an updated overview on the role of therapeutic drug monitoring (TDM) of biological therapies in inflammatory bowel disease (IBD). We examine the data behind TDM for the antitumor necrosis factor agents, vedolizumab and ustekinumab, in patients with IBD. In addition, we discuss reactive vs. proactive TDM.

RECENT FINDINGS

There is a positive correlation between biologic drug concentrations and favorable therapeutic outcomes in IBD, although the majority of data refer to antitumor necrosis factor therapy. Reactive TDM has rationalized the management of patients with IBD with loss of response to biological therapy. Moreover, reactive TDM of infliximab has been proven to be more cost-effective when compared with empiric dose optimization. Preliminary data suggest that proactive TDM of infliximab and adalimumab applied in patients with clinical response/remission is associated with better therapeutic outcomes compared with standard of care (empiric treatment and/or reactive TDM).

SUMMARY

For all biologics in IBD, there is a positive correlation between drug concentrations and favorable therapeutic outcomes. Reactive TDM is the new standard of care for optimizing biologic therapies in IBD, whereas recent data suggest an important role of proactive TDM for optimizing antitumor necrosis factor therapy in IBD.

Vedolizumab trough level monitoring in inflammatory bowel disease: a state-of-the-art overview

BACKGROUND

Therapeutic drug monitoring involves therapeutic modifications based on the measurement of drug levels and antidrug antibodies. The viability of therapeutic drug monitoring in vedolizumab-treated patients with inflammatory bowel disease remains questioned.

MAIN BODY

Accumulating evidence from clinical trials and real-world data suggests that an exposure-efficacy relationship may exist for vedolizumab in inflammatory bowel disease, but results are not as straightforward as they are for anti-tumour necrosis factor-α therapy. Robust target vedolizumab trough levels are currently missing, since available data are heterogenous and prospective, interventional pharmacokinetic-pharmacodynamic studies are lacking. The positioning of vedolizumab drug monitoring in therapeutic algorithms is yet to be defined.

CONCLUSION

Therapeutic drug monitoring has the potential to improve the outcome parameters of vedolizumab-treated patients with inflammatory bowel disease. Before the therapeutic drug monitoring of vedolizumab can be implemented in a widespread fashion, prospective studies are needed to evaluate the effect of vedolizumab dose optimisation. These studies should focus on objective disease markers and vedolizumab drug levels, and define thresholds for optimal drug exposure.

A product review of vedolizumab in inflammatory bowel disease

Vedolizumab is a monoclonal antibody to the α4β7 integrin that selectively reduces intestinal lymphocyte trafficking, thereby providing a safe and effective treatment option for patients with inflammatory bowel disease (IBD). This product review outlines the unique mechanism of vedolizumab in addition to efficacy, safety, pharmacokinetic and pharmacodynamic data from clinical trials, observational studies and meta-analyses. Vedolizumab has been shown to be effective as a first- or second-line induction and maintenance therapy in both ulcerative colitis (UC) and Crohn's disease (CD). Prolonged induction therapy may increase efficacy, particularly in tumor necrosis factor-alpha-exposed CD patients. To date, no drug-specific safety signals have been identified. In addition to the presence of an apparent exposure-response relationship, vedolizumab has demonstrated consistent pharmacodynamic effects on α4β7, mucosal vascular addressin cell adhesion molecule 1 and other cell adhesion molecules. Future efforts should focus on identifying predictive biomarkers capable of guiding personalized IBD treatment with vedolizumab.

Maneuvering Clinical Pathways for Crohn's Disease

PURPOSE OF REVIEW

Crohn's disease management has changed significantly with increasing use of biologics. We review the recent literature on the clinical management of Crohn's disease and new approaches in selecting and optimizing therapy.

RECENT FINDINGS

Recent studies have addressed the efficacy of proactive anti-TNFα trough level monitoring, the efficacy of biosimilars, and the efficacy and immunogenicity of newer biologics including anti-integrin therapy and anti-IL12/23 therapy. Optimizing anti-TNFα therapy according to trough concentrations correlates with improved remission rates. Patients can be switched from the reference drug to a biosimilar, or vice versa, without a measurable change in efficacy, safety, or immunogenicity. Immunomodulators are effective in decreasing immunogenicity and boosting anti-TNFα drug level. The anti-integrin and anti-IL12/23 therapies are effective as induction and maintenance therapy with low immunogenicity and excellent safety profiles. Patients at high risk for post-operative recurrence should be started on a biologic therapy within 4 weeks post-op. Multiple biologic therapies are currently available for treatment of Crohn's disease including anti-TNFα therapy, anti-integrin therapy, and anti-IL12/23 therapy. The choice of first-line therapy should be based on individual risk-benefit analysis, route of administration, and patient preference. Patient with inadequate response should have their trough level checked and therapy optimized. Therapeutic prophylaxis for post-operative recurrence should be based on patient's risk factors for recurrence.

Mucosal healing in inflammatory bowel disease: Expanding horizon

Management of inflammatory bowel diseases has witnessed paradigm shift from 5-aminosalicylic acid and glucocorticoids to various immunosuppressant and biological agents. Targets of therapy have also been changed drastically from symptomatic improvement to mucosal, histological healing, and recently transmural healing. Mucosal healing is associated with reduced need of steroid therapy, hospitalization, and surgery. However, whether mucosal healing alters the natural history of disease remains to be proven. Though assessment of mucosal healing is traditionally done by endoscopic examination, newer tests like fecal calprotectin, capsule endoscopy, and magnetic resonance enterography have also shown promising results. Various immunosuppressants and biologicals are the main therapy being used to achieve mucosal healing. This review focuses on the need for achieving mucosal healing, its long-term benefits, various methods and algorithm for diagnosis, and achievement of mucosal healing.

Early vedolizumab trough levels predict combined endoscopic and clinical remission in inflammatory bowel disease

Background

The relationship between vedolizumab trough levels and combined endoscopic and clinical remission is unknown.

Objective

To compare vedolizumab trough levels in patients with and without combined remission within the first year of treatment.

Methods

We prospectively collected vedolizumab trough levels in 51 consecutive patients (28 Crohn's disease (CD) and 23 ulcerative colitis (UC)) before all infusions up to week 22, and at weeks 38 and 54, with concentrations measured after study completion. Centrally read endoscopy was performed at a median of 46 weeks. The primary outcome was combined endoscopic (CD: Simple endoscopic score for CD (SES-CD) < 4 without ulceration; UC: Mayo endoscopic subscore ≤ 1) and clinical remission (CD: resolution of abdominal pain; UC: resolution of rectal bleeding; both: resolution of altered bowel habit).

Results

Median vedolizumab trough levels at weeks 6 (25.7 vs 15.6 µg/mL; P = 0.015) and 22 (15.1 vs 4.9 µg/mL; P = 0.001) were higher in patients with combined remission. A threshold of 22 µg/mL at week 6 (area under the curve (AUC) 0.733; 95% confidence interval 0.567-0.899) and 8 µg/mL at week 22 (AUC 0.819; 95% confidence interval 0.692-0.946) predicted combined remission.

Conclusion

Early vedolizumab trough levels predicted combined endoscopic and clinical remission highlighting their possible use in clinical practice.