Post-Induction Adalimumab Concentration is Associated with Short-Term Mucosal Healing in Patients with Ulcerative Colitis

A prediction method for the individual serum concentration and therapeutic effect for optimizing adalimumab therapy in inflammatory bowel disease

OBJECTIVES

Adalimumab (ADM) therapy is effective for inflammatory bowel disease (IBD), but a significant number of IBD patients lose response to ADM. Thus, it is crucial to devise methods to enhance ADM's effectiveness. This study introduces a strategy to predict individual serum concentrations and therapeutic effects to optimize ADM therapy for IBD during the induction phase.

METHODS

We predicted the individual serum concentration and therapeutic effect of ADM during the induction phase based on pharmacokinetic and pharmacodynamic (PK/PD) parameters calculated using the empirical Bayesian method. We then examined whether the predicted therapeutic effect, defined as clinical remission or treatment failure, matched the observed effect.

RESULTS

Data were obtained from 11 IBD patients. The therapeutic effect during maintenance therapy was successfully predicted at 40 of 47 time points. Moreover, the predicted effects at each patient's final time point matched the observed effects in 9 of the 11 patients.

CONCLUSION

This is the inaugural report predicting the individual serum concentration and therapeutic effect of ADM using the Bayesian method and PK/PD modelling during the induction phase. This strategy may aid in optimizing ADM therapy for IBD.

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

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

Prospective Observational Evaluation of the Time-Dependency of Adalimumab Immunogenicity and Drug Concentration in Ulcerative Colitis Patients: the POETIC II Study

BACKGROUND AND AIMS

Home self-injection of the human anti-tumour necrosis alpha [anti-TNFα] monoclonal adalimumab complicates prospective serial-sampling studies. Although a recent study examined adalimumab levels and immunogenicity in Crohn's disease [CD] patients, prospective real-world data from ulcerative colitis [UC] patients are lacking.

METHODS

A three-monthly home-visit programme from induction was established prospectively for UC patients. Clinical scores were determined at each visit, and sera were obtained for assessment of drug and anti-adalimumab antibody levels. Calprotectin was measured using a smartphone-based app. This cohort was compared to a parallel prospective cohort of adalimumab-treated CD patients [POETIC1].

RESULTS

Fifty UC patients starting adalimumab [median follow-up 28 weeks] were compared to 98 adalimumab-treated CD patients [median follow-up 44 weeks]. Only 11/50 UC patients [22%] continued treatment to the end of the follow-up compared with 50/98 [51%] CD patients (odds ratio [OR] = 0.27, p = 0.001). Loss of response was significantly more common in UC patients [OR = 3.2, p = 0.001]. Seventeen patients [34%] in the UC cohort developed anti-adalimumab antibodies, 9/17 [52.9%] as early as week 2. There was no difference between patient cohorts in the overall development of anti-adalimumab antibodies [34% vs 30.6%, respectively, OR = 1.67, p = 0.67], nor was there a difference in early immunogenicity [OR = 1.39, p = 0.35]. There was no difference in low drug levels [<3 µg/mL] between the two cohorts [OR = 0.87, p = 0.83].

CONCLUSIONS

Loss of response to adalimumab therapy was significantly more common in the UC compared to the CD cohort and was driven by a higher rate of non-immunogenic, pharmacodynamic parameters.

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.

Predictor of primary response to antitumor necrosis factor-α therapy for inflammatory bowel disease: a single-center observational study

BACKGROUND

It is necessary to find reliable and appropriate predictors of primary response to anti-TNFα therapy (infliximab and adalimumab) in inflammatory bowel disease (IBD) so as to avoid treatment failure and select optimal treatment. The aim of this study is to reveal useful predictors of the response to anti-TNFα treatment from baseline to 2 months after initial administration of anti-TNFα for individual IBD patients using our pharmacokinetic and pharmacodynamic (PK/PD) model at the time of second administration.

METHODS

We retrospectively analyzed 26 IBD patients who received anti-TNFα. In the PK/PD model, inflammation was assumed to be suppressed based on the action of anti-TNFα at the rate constant of Kanti-TNFα (day-1). Kanti-TNFα0 (day-1) is Kanti-TNFα in the absence of anti-TNFα. We expressed inflammation caused by factors not affected by the action of anti-TNFα using the rate constant Kelse (day-1). Using univariate and multivariate linear regressions, we statistically analyzed factors related to the improvement of disease activity index.

RESULTS

The significant correlation between Kanti-TNFα0/Kelse and the improvement of disease activity index was shown in Crohn's disease patients (univariate: estimated value 2.4; P = 0.003; and multivariate: 1.8; P = 0.012) and ulcerative colitis patients (univariate: 0.12; P = 0.011), and no other factors were significant.

CONCLUSION

This is the first study to present a useful predictor of primary response to anti-TNFα of individual IBD patients at second administration. The Kanti-TNFα0/Kelse ratio may help to select the optimal therapeutic drug and avoid the improper continuous administration of anti-TNFα in the induction phase.

Therapeutic drug monitoring for biological medications in inflammatory bowel disease

Therapeutic drug monitoring (TDM) is the measurement of serum drug concentrations and anti-drug-antibodies (ADA) for biologic therapies used to treat inflammatory bowel disease (IBD). The aim of this article is to review the current literature concerning reactive and proactive TDM for both adults and children with IBD. Although optimal trough concentration windows for some of these medications are not well defined, there is mounting evidence to suggest that reactive TDM is associated with favorable therapeutic outcomes, including less immunogenicity, greater drug exposure, and a decreased risk of treatment failure. Moreover, while the exact mechanism of loss of response is not fully elucidated, the vast majority of studies have reported a decreased incidence of nonresponse and secondary loss of response when TDM is implemented. Proactive TDM, while even less understood in the literature, employs a schedule of preemptive analysis of serum trough concentrations to accordingly adjust the patient's biologic dosage. Proactive TDM may decrease the need for IBD-related surgery/hospitalization, and therefore merits future studies of investigation.

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.

Proactive versus Reactive Therapeutic Drug Monitoring: Why, When, and How?

BACKGROUND

Up to a third of inflammatory bowel disease) patients show primary nonresponse to antitumor necrosis factor (anti-TNF) biological therapy, and of those who respond, up to 40% develop secondary loss of response (LOR). Therapeutic drug monitoring (TDM) plays a crucial role in assessing patients with LOR to guide therapy by giving more of the drug or switching to a different biological agent. Although reactive TDM is suggested or recommended by the majority of gastroenterology associations, proactive TDM seems to be more controversial.

SUMMARY

In this article, we discuss the updated guidelines on TDM and will also discuss the available data supporting proactive and reactive TDM in patients with Crohn's disease and those with ulcerative colitis using the different available biological agents.

KEY MESSAGES

Therapeutic drug monitoring (TDM) is a valuable tool to aid in inflammatory bowel disease (IBD) therapy optimization. Reactive TDM is widely accepted in IBD patients with suspected loss of response, especially in those receiving antitumor necrosis factor (anti-TNF) agents. Proactive TDM is emerging as a reasonable approach to patients initiated on anti-TNF therapy, specifically infliximab and, to some extent, adalimumab, particularly for patients with severe ulcerative colitis and fistulizing Crohn's disease. Similarly, TDM may play a role in patients considering de-escalation from combination therapy. To date, proactive TDM is not widely applied to ustekinumab and vedolizumab and more data are required before this becomes part of clinical practice.

Present and Future Therapeutic Approaches to Barrier Dysfunction

There is converging and increasing evidence, but also uncertainty, for the role of abnormal intestinal epithelial barrier function in the origin and development of a growing number of human gastrointestinal and extraintestinal inflammatory disorders, and their related complaints. Despite a vast literature addressing factors and mechanisms underlying changes in intestinal permeability in humans, and its connection to the appearance and severity of clinical symptoms, the ultimate link remains to be established in many cases. Accordingly, there are no directives or clinical guidelines related to the therapeutic management of intestinal permeability disorders that allow health professionals involved in the management of these patients to carry out a consensus treatment based on clinical evidence. Instead, there are multiple pseudoscientific approaches and commercial propaganda scattered on the internet that confuse those affected and health professionals and that often lack scientific rigor. Therefore, in this review we aim to shed light on the different therapeutic options, which include, among others, dietary management, nutraceuticals and medical devices, microbiota and drugs, and epigenetic and exosomes-manipulation, through an objective evaluation of the scientific publications in this field. Advances in the knowledge and management of intestinal permeability will sure enable better options of dealing with this group of common disorders to enhance quality of life of those affected.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

DISCUSSION

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

Higher Maintenance Adalimumab Trough Levels are Associated With Achievement of Advanced Remission Targets in Patients With Inflammatory Bowel Disease

BACKGROUND

Biomarker normalization and endoscopic remission are superior to clinical remission in achieving improved long-term clinical outcomes in patients with inflammatory bowel diseases.

GOAL

To study whether higher maintenance adalimumab levels are associated with clinical remission, biomarker normalization, and endoscopic remission.

STUDY

Data were collected retrospectively from the patients' medical records. We defined clinical remission as a Harvey Bradshaw Index ≤5 or a partial Mayo score ≤2 for Crohn's disease (CD) and ulcerative colitis (UC), respectively, biomarker normalization as a C-reactive protein <0.5 mg/dL and/or calprotectin <250 (mg/kg), endoscopic remission as a (simple endoscopic score-CD) ≤3/4 for ileal/extensive CD, respectively, or an endoscopic Mayo score ≤1 for UC, and deep remission as the combination of clinical and endoscopic remission with normal biomarkers.

RESULTS

Ninety-seven patients were included (82 CD and 15 UC). Patients who achieved clinical remission, biomarker normalization, or endoscopic remission had higher serum trough adalimumab levels compared with patients not in remission [mean (M)±standard error (SE)=8.98±0.78 vs. 5.92±0.96 μg/mL; P=0.016, 9.38±0.85 vs. 5.48±0.87 μg/mL; P=0.002; 9.13±0.88 vs. 6.02±0.77 μg/mL; P=0.019, respectively]. Receiver-operating curve analysis showed that an adalimumab level of ≥8.25 μg/mL was associated with deep remission (sensitivity 84%, specificity 70%, area under the curve 0.775; P<0.001).

CONCLUSION

Clinical remission, biomarker normalization, and endoscopic remission are positively associated with adalimumab trough levels. Adalimumab level of ≥8.25 μg/mL is associated with deep remission. This study provides additional data to guide therapeutic drug monitoring with adalimumab.

Clinical outcomes and predictors of response for adalimumab in patients with moderately to severely active ulcerative colitis: a KASID prospective multicenter cohort study

Background/Aims

This study assessed the efficacy and safety of adalimumab (ADA) and explored predictors of response in Korean patients with ulcerative colitis (UC).

Methods

A prospective, observational, multicenter study was conducted over 56 weeks in adult patients with moderately to severely active UC who received ADA. Clinical response, remission, and mucosal healing were assessed using the Mayo score.

Results

A total of 146 patients were enrolled from 17 academic hospitals. Clinical response rates were 52.1% and 37.7% and clinical remission rates were 24.0% and 22.0% at weeks 8 and 56, respectively. Mucosal healing rates were 39.0% and 30.1% at weeks 8 and 56, respectively. Prior use of anti-tumor necrosis factor-α (anti-TNF-α) did not affect clinical and endoscopic responses. The ADA drug level was significantly higher in patients with better outcomes at week 8 (P<0.05). In patients with lower endoscopic activity, higher body mass index, and higher serum albumin levels at baseline, the clinical response rate was higher at week 8. In patients with lower Mayo scores and C-reactive protein levels, clinical responses, and mucosal healing at week 8, the clinical response rate was higher at week 56. Serious adverse drug reactions were identified in 2.8% of patients.

Conclusions

ADA is effective and safe for induction and maintenance in Korean patients with UC, regardless of prior anti-TNF-α therapy. The ADA drug level is associated with the efficacy of induction therapy. Patients with better short-term outcomes were predictive of those with an improved long-term response.

Therapeutic monitoring of adalimumab at non-trough levels in patients with inflammatory bowel disease

Adalimumab (ADA) trough level and anti-ADA antibody (AAA) positivity influence mucosal healing and loss of response in patients with inflammatory bowel disease (IBD). In this study, we clarified the correlation between ADA monitoring, including non-trough level, and real-world IBD clinical outcomes. This retrospective, observational, single-center study involved patients with ulcerative colitis (19) and Crohn's disease (33) treated with ADA from January 2007 to August 2018. Serum ADA and AAA levels were measured 4‒14 days after ADA administration. The AAA positivity rate was 23.1% (12/52). ADA continuity was higher in AAA-negative patients than in AAA-positive patients (P = 0.223). Receiver operating characteristic (ROC) analysis revealed that a serum AAA cut-off of 9.2 μg/mL was associated with ADA continuity. The ADA level was significantly higher in the endoscopic remission group than in the non-remission group (P = 0.02). Based on the ROC curve analysis results of serum ADA level and endoscopic remission, the cut-off value of the serum ADA level was set to 11.1 μg/mL. Under the combined use of ADA with immunomodulators and AAA positivity, ADA continuity was significantly higher when the serum AAA level at 4-14 days after ADA administration was ≥9.2 μg/mL. Furthermore, endoscopic remission can be expected with a serum ADA level of ≥11.1 μg/mL. Overall, to predict clinical outcomes, it would be useful to measure the blood level of ADA regardless of the timing of the trough.

Association of Early Postinduction Adalimumab Exposure With Subsequent Clinical and Biomarker Remission in Children with Crohn's Disease

BACKGROUND

Data on the association between early postinduction serum adalimumab (ADA) trough levels (TLs) and objective outcomes are scarce. The aim of this study was to investigate whether early ADA TLs at weeks 4 and 8 are associated with clinical and biomarker remission at week 24 in pediatric Crohn's disease (CD).

METHODS

Adalimumab TLs at weeks 4 and 8 were prospectively measured in anti-TNF-naïve children initiating treatment with ADA monotherapy for luminal inflammatory CD. The primary outcome was combined clinical and biomarker remission at week 24, defined as achieving steroid-free clinical remission (Pediatric CD activity index <10) and biomarker remission (fecal calprotectin <250 µg/g and CRP <5 µg/mL).

RESULTS

Among 65 patients, 39 (60%) achieved combined clinical/biomarker remission at week 24 without dose escalation. Adalimumab TLs at both weeks 4 and 8 were significantly higher in remitters vs nonremitters at week 24 (P < 0.001 and P = 0.002, respectively). Adalimumab levels at weeks 4 and 8 were good predictors of combined clinical/biomarker remission at week 24 (area under the curve, 0.887, 95% CI, 0.798-0.942; and area under the curve, 0.761, 95% CI, 0.632-0.899, respectively). The best ADA TL cutoffs at weeks 4 and 8 for predicting clinical/biomarker remission at week 24 were 22.5 µg/mL (80% sensitivity, 90% specificity, positive likelihood ratio [LR+] 8.0, negative LR [LR-] 0.2) and 12.5 µg/mL (94% sensitivity, 60% specificity, LR+ 2.4, LR- 0.1), respectively. Higher induction doses per m2 correlated positively with TLs at weeks 4 and 8.

CONCLUSION

Greater early ADA exposure is associated with superior clinical/biomarker outcomes at week 24.

Predictive value of blood concentration of biologics on endoscopic inactivity in inflammatory bowel disease: A systematic review

BACKGROUND

Although blood concentration of biologics is an important composition of disease management in inflammatory bowel disease (IBD) patients, complexity and uncertainty of biological management encourage many disputes in predicting the outcome of IBD patients through blood concentration of biologics.

AIM

To verify the predictive value of blood concentration of biologics on endoscopic inactivity in IBD patients under different situations.

METHODS

We searched PubMed/MEDLINE, Embase, and Web of Science up to May 2020 and identified IBD patients as the research cohort as well as the correlations between blood concentration of biologics and endoscopic inactivity in IBD patients as the research direction.

RESULTS

A total of 23 articles with 30 clinical studies and 1939 IBD patients were included. The predictive cut-off value of blood concentration of infliximab on mucosal healing should be 2.7-10.6 μg/mL in IBD. Blood concentration of infliximab reaching 5.0-12.7 μg/mL or more increased the probability of fistula healing/closure in perianal fistulizing Crohn's disease. Blood concentration of adalimumab reaching 7.2-16.2 μg/mL or more could predict mucosal healing in IBD. The predictive cut-off value of blood concentration of adalimumab on fistula healing/closure should be 5.9-9.8 μg/mL in perianal fistulizing Crohn's disease. Blood concentration of vedolizumab surpassing 25.0 μg/mL indicated mucosal healing in ulcerative colitis patients under maintenance therapy and the predictive cut-off value of blood concentration on mucosal healing or endoscopic remission under induction therapy in IBD could be 8.0-28.9 μg/mL.

CONCLUSION

Blood concentration of biologics should not be utilized to predict endoscopic inactivity of IBD independently due to discrepancies in clinical studies, whereas conducting therapeutic drug monitoring intensively contributes to precise therapy.

Predictors and Early Markers of Response to Biological Therapies in Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD) are chronic conditions that primarily affect the gastrointestinal tract, with a complex pathogenesis; they are characterized by a significant heterogeneity of clinical presentations and of inflammatory pathways that sustain intestinal damage. After the introduction of the first biological therapies, the pipeline of therapies for IBD has been constantly expanding, and a significant number of new molecules is expected in the next few years. Evidence from clinical trials and real-life experiences has taught us that up to 40% of patients do not respond to a specific drug. Unfortunately, to date, clinicians lack a valid tool that can predict each patient’s response to therapies and that could help them in choosing what drug to administer. Several candidate biomarkers have been investigated so far, with conflicting results: clinical, genetic, immunological, pharmacokinetic and microbial markers have been tested, but no ideal marker has been identified so far. Based on recent evidence, multiparametric models seemingly hold the greatest potential for predicting response to therapy. In this narrative review, we aim to summarize the current knowledge on predictors and early markers of response to biological therapies in IBD.

Optimization of biologics to reduce treatment failure in inflammatory bowel diseases

Moderate to severe inflammatory bowel disease patients can fail to respond to conventional therapy and/or to biologic treatment. In the era of TNFα antagonists and other non-anti-TNF biologic drugs, it is important to review the literature on biologic treatment failure, which could be defined as primary non-response, secondary loss of response and intolerance. Therapeutic drug monitoring (TDM), that is, drug trough level and antidrug antibodies, should enable to determine the mechanisms of treatment failure and to optimize drug efficacy. There is a consensus on reactive TDM at the time of loss of response. Proactive TDM could be of interest during induction and/or maintenance, but randomized controlled trials are required.

Optimizing Antitumor Necrosis Factor Treatment in Pediatric Inflammatory Bowel Disease With Therapeutic Drug Monitoring

Biological agents have revolutionized inflammatory bowel disease treatment but primary nonresponse and secondary loss of response are common with resulting adverse outcomes. Clinical trials demonstrated an association between serum drug concentrations, as well as the presence of antidrug antibodies, and loss-of-response. Therapeutic drug monitoring (TDM), defined as the evaluation of drug concentrations and antidrug antibodies, is appearing as a strategy to optimize treatment and take full advantage from these drugs. TDM appears to be a promising tool in clinical practice, especially in pediatric patients, who have pronounced fluctuations in the pharmacokinetics of the drugs.The authors present a literature review about antitumor necrosis factor therapy optimization based on personalized treatment strategies according to TDM and possible strategies to recapture loss of response, including an algorithm for practical management.

Therapeutic Drug Monitoring of Biologics During Induction to Prevent Primary Non-Response

Biologic therapies have revolutionized the management of inflammatory bowel disease [IBD], but primary and secondary non-responses occur in a significant proportion of patients. Therapeutic drug monitoring [TDM] now has an established role in the treatment algorithm for managing secondary loss of response to anti-tumour necrosis factor [anti-TNF] agents during maintenance therapy. Data to support the use of TDM in the management of secondary loss of response to vedolizumab and ustekinumab are emerging. The potential to prevent primary non-response to biologic agents during induction is of equal, and potentially greater, clinical importance. Again, most data supporting the use of 'proactive' TDM during induction pertains to the use of anti-TNF agents, but signals of efficacy for the use of TDM during induction with other biologic classes are now appearing. This review aims to summarize data on the use of TDM during induction to prevent pharmacokinetic primary non-response to all three classes of biologic therapy currently available for the treatment of IBD.

Long-term Outcomes of Adalimumab Therapy in Korean Patients with Ulcerative Colitis: A Hospital-Based Cohort Study

BACKGROUND/AIMS

Studies on long-term outcomes of adalimumab therapy in non-Caucasian patients with ulcerative colitis (UC) are lacking.

METHODS

We analyzed long-term outcomes of Korean UC patients treated with adalimumab at the Asan Medical Center, Seoul, Korea.

RESULTS

Between July 2013 and October 2018, adalimumab therapy was started in a total of 100 patients with UC (65 males [65.0%]; median age, 39.5 years [interquartile range, 23.3 to 49.8 years]; and median disease duration, 3.0 years [interquartile range, 1.0 to 7.0 years]). The median duration of adalimumab therapy was 13.5 months (interquartile range, 4.0 to 32.0 months). Eight of 100 patients (8.0%) received induction therapy only, four (4.0%) of whom ultimately underwent colectomy. Of 92 patients who received adalimumab maintenance therapy, 30 (30.0%) stopped adalimumab therapy due to loss of response, and one patient (1.0%) was lost to follow-up. Among the 92 patients who received adalimumab maintenance therapy, the cumulative proportions of patients remaining on adalimumab maintenance therapy were 70.0% at 1 year and 48.9% at 5 years. High partial Mayo score after 8 weeks of adalimumab therapy (hazard ratio [HR], 1.217; 95% confidence interval [CI], 1.040 to 1.425; p=0.014) and a history of exposure to two biologic agents before adalimumab therapy (HR, 4.722; CI, 1.033 to 21.586; p=0.045) were predictors of adalimumab discontinuation.

CONCLUSIONS

Long-term outcomes of adalimumab therapy in Korean UC patients appear to be comparable to those in previously published Western studies. Furthermore, previous exposure to multiple biologic agents before adalimumab therapy and disease activity after 8 weeks of adalimumab therapy were predictors of adalimumab discontinuation.

Potential Utility of Therapeutic Drug Monitoring of Adalimumab in Predicting Short-Term Mucosal Healing and Histologic Remission in Pediatric Crohn's Disease Patients

BACKGROUND

Limited data exist regarding mucosal healing (MH) and therapeutic drug monitoring (TDM) in pediatric Crohn's disease (CD) patients treated with adalimumab (ADL). We aimed to investigate the associations between ADL trough levels (TLs) and MH, and between ADL TLs and histologic remission (HR) at 16 weeks from ADL treatment in pediatric CD patients.

METHODS

This was a prospective study on moderate-to-severe luminal pediatric CD patients receiving ADL. Ileocolonoscopies and biopsies, as well as clinical activity assessments, laboratory examinations, including tests for ADL TLs and antibody to ADL, were performed 16 weeks after ADL initiation. MH was defined as a Simple Endoscopic Score for CD of 0. HR was defined as the complete absence of microscopic inflammation.

RESULTS

Seventeen subjects (13 males, 4 females) were included. At 16 weeks from ADL initiation, 14 (82.4%), 8 (47.1%), and 4 (23.5%) patients achieved clinical remission, MH, and HR, respectively. ADL TLs were significantly higher in patients who achieved MH compared to those who did not (13.0 ± 6.5 vs. 6.2 ± 2.6 μ/mL, respectively; P = 0.023) and also significantly higher in patients who achieved HR compared to those who did not (17.9 ± 5.3 vs. 6.8 ± 2.5 μ/mL, respectively; P = 0.02). The optimal TL for predicting MH was 8.76 μ/mL.

CONCLUSION

Serum ADL TLs at 16 weeks were significantly higher in pediatric patients with CD who achieved MH and HR, respectively. TDM may guide in optimizing treatment efficacy and better target MH in the era of treat-to-target.

Matrix Metalloproteinase 3 Predicts Therapeutic Response in Inflammatory Bowel Disease Patients Treated With Infliximab

BACKGROUND AND AIMS

Inflammatory bowel diseases (IBDs) are treated with anti-TNF agents. Strategies to monitor response to therapy may improve clinical control of the disease and reduce economical costs. Previous evidence suggests cleavage of infliximab (IFX) by Matrix Metalloproteinase 3 (MMP3) as a mechanism leading to loss of response. Our study aimed to evaluate if MMP3 serum levels could be considered an early marker of anti-TNF nonresponse and to analyze the correlation with other biochemical markers of treatment failure such as IFX trough levels and anti-IFX antibodies, inflammatory markers, and albumin levels.

METHODS

Retrospectively, 73 IBD patients who had received IFX for at least 1 year were enrolled: 35 patients were responders and 38 were nonresponders at 52 weeks. Clinical and biochemical data (Harvey-Bradshaw index [HBI], Mayo score, body mass index [BMI], C-reactive protein [CRP], fecal calprotectin and albumin levels), MMP3 serum levels, and drug monitoring were assessed at baseline, postinduction, and 52 weeks.

RESULTS

The MMP3 levels were similar at baseline (19.83 vs 17.92 ng/mL), but at postinduction, patients who failed to respond at 1 year had significantly higher levels than patients who responded (26.09 vs 8.68 ng/mL, P < 0.001); the difference was confirmed at week 52 (29.56 vs 11.48 ng/mL, P < 0.001). The MMP3 levels tended to be higher in patients without antidrug antibodies than in patients with antidrug antibodies at postinduction and 52 weeks.

CONCLUSIONS

The MMP3 serum determination may represent an early marker of response to infliximab.

Early Adalimumab and Anti-Adalimumab Antibody Levels for Prediction of Primary Nonresponse in Ankylosing Spondylitis Patients

This study aimed at exploring the concentration‐effect relationship of adalimumab and early adalimumab and anti‐adalimumab antibody (AAA) levels in predicting primary nonresponse in a real‐world pilot cohort of patients with ankylosing spondylitis. Thirty‐one patients were included. The Ankylosing Spondylitis Disease Activity Score improved with increasing adalimumab trough level at week 12 and reached a major improvement with levels between 8 and 12 μg/mL. Moreover, weeks 4 and 2 adalimumab levels below 4.28 and 3.37 μg/mL were predictive of primary nonresponse (area under the curve (AUC) = 0.89, 0.88; P = 0.0003, P = 0.034, respectively). Week 4 AAA signal‐to‐noise levels were significantly higher among primary nonresponders, and the cutoff for primary nonresponse prediction was above 5.31 (AUC = 0.81; P = 0.004). Adalimumab trough levels in a range of 8–12 μg/mL are optimum to reach major improvement, and lower adalimumab with higher AAA levels at the early stage (week 4) predict primary nonresponse by supporting proactive monitoring to optimize adalimumab therapy.

Patient sex does not affect endoscopic outcomes of biologicals in inflammatory bowel disease but is associated with adverse events

PURPOSE

Biological therapies are currently the mainstay in the treatment of patients with inflammatory bowel diseases (IBD). Several factors are known to influence the efficacy and tolerability of biologicals, such as CRP levels or previous biological use. Whether patient sex affects the efficacy or tolerability is unclear but would help with better risk and benefit stratification. This systematic review assesses patient sex on the efficacy and tolerability of biological therapies in IBD patients.

METHODS

A systematic literature review was performed using Embase (including MEDLINE), MEDLINE OvidSP, Cochrane Central Register of Controlled Trials, Web of Science and PubMed. The primary outcome was the influence of patient sex on endoscopic outcomes in IBD patients treated with biologicals. The secondary outcome was the influence of patient sex on adverse events. Studies were included in the assessment regardless of study type or setting.

RESULTS

The search yielded 19,461 citations; after review, 55 studies were included in the study, involving 28,465 patients treated with adalimumab, certolizumab pegol, infliximab, or vedolizumab. There was no significant association between patient sex and endoscopic efficacy in 41 relevant studies. Increased adverse events were associated with female sex in 7 out of 14 relevant studies.

CONCLUSIONS

There is no evidence for a sex difference in endoscopically measured response to biological therapies in IBD patients. However, there is an influence of sex on the occurrence of adverse events.

Association of Infliximab Levels With Mucosal Healing Is Time-Dependent in Crohn's Disease: Higher Drug Exposure Is Required Postinduction Than During Maintenance Treatment

BACKGROUND

Infliximab levels have been reported to be associated with mucosal healing (MH) in Crohn's disease (CD). However, whether the association differs between postinduction (week 14) and maintenance (week 30) has seldom been investigated. We aimed to analyze the association between serum infliximab trough levels and MH at the 2 different time points.

METHODS

A retrospective study of CD patients treated with infliximab in a tertiary referral center between January 2012 and May 2018 was conducted. MH was defined as absence of ulceration by endoscopy. Correlations between infliximab level and MH were investigated at 2 specific time points, weeks 14 and 30.

RESULTS

Median infliximab levels were higher in patients with MH than those without at weeks 14 (7.5 vs 1.5 μg/mL; P < 0.001) and 30 (5.9 vs 0.5 μg/mL; P < 0.001). The median levels in patients with MH at week 14 were higher than at week 30 (7.5 vs 5.9 μg/mL; P < 0.05). Multivariate analysis showed that infliximab level was independently associated with MH (both P < 0.001 at weeks 14 and 30). Infliximab level above 4.85 μg/mL and 2.85 μg/mL identified patients with MH at week 14 (area under the curve [AUC], 0.796; P < 0.001) and week 30 (AUC, 0.780; P < 0.001) with 80% specificity. The rates of MH reached a plateau (>85%) when infliximab levels were above 10 and 6 μg/mL at weeks 14 and 30, respectively.

CONCLUSIONS

Infliximab levels correlated with MH at weeks 14 and 30 in CD patients. Higher levels might be required to achieve MH at postinduction than during maintenance treatment.

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.

Vedolizumab use in patients with inflammatory bowel diseases undergoing surgery: clinical trials and post-marketing experience

Background

Patients with inflammatory bowel diseases frequently require surgery, but immunotherapies used in disease management may increase the risk of post-operative complications. We investigated frequencies of post-operative complications in patients who received vedolizumab-a gut-selective antibody approved for the treatment of moderately to severely active ulcerative colitis and Crohn's disease-in clinical-trial and post-marketing settings.

Methods

This post hoc analysis of safety data from GEMINI 1, GEMINI 2, and long-term safety studies included patients who had had colectomy or bowel surgery/resection. Data from the post-marketing Vedolizumab Global Safety Database were also analysed (data cutoff point: 19 May 2016). Adverse events relating to post-operative complications were identified using Medical Dictionary for Regulatory Activities preferred terms.

Results

Of 58 total surgeries in patients included in GEMINI 1 and GEMINI 2, post-operative complications were reported for 3/51 vedolizumab-treated patients (5.9%) and 1/7 placebo-treated patients (14.3%). In the long-term safety study, 157/2,243 patients (7%) had colectomy or bowel surgery/resection; of these 157 patients who underwent surgery, 11 (7%) experienced a post-operative complication. Median time between last pre-operative vedolizumab dose and surgery was 23 days in GEMINI 1, 20 days in GEMINI 2, and 39‒40 days in the long-term safety study. In the post-marketing setting, based on data covering approximately 46,978 patient-years of vedolizumab exposure, post-operative complications were reported in 19 patients.

Conclusions

In clinical trials, complications of colectomy and bowel surgery/resection appeared infrequent, with minimal difference between vedolizumab and placebo. The frequency of post-operative complications in the post-marketing setting appears low.

Vedolizumab Trough Levels and Histological Healing During Maintenance Therapy in Ulcerative Colitis

BACKGROUND AND AIMS

Histological healing may be the ultimate therapeutic goal in ulcerative colitis [UC]. We investigated, for the first time, the association between vedolizumab trough levels and histological healing in UC.

METHODS

This is a single-centre retrospective cohort study including all consecutive UC patients on vedolizumab maintenance therapy who had a histological evaluation blindly to clinical data and underwent therapeutic drug monitoring, between June 2014 and March 2018. Per-event analysis was performed. Histological healing was defined as a Nancy histological index ≤1.

RESULTS

Thirty-five histological samples were analysed. Median [interquartile range] vedolizumab trough levels were higher in the group with histological healing (31.5 [25-49.1] μg/mL) compared with the group without histological healing (15 [9-26.6] μg/mL, p = 0.02). The higher vedolizumab trough level quartiles tended to be associated with greater rates of histological healing [p = 0.10]. A cut-off vedolizumab trough level of 25 μg/mL predicted histological healing with an accuracy of 74% and an area under the receiver operating curve of 0.62 [95% confidence interval 0.58-0.92, p = 0.004]. Bivariate analysis identified a vedolizumab trough level ≥25 µg/mL [p = 0.006], a partial Mayo score ≤1 [p = 0.008], C-reactive protein level <5 mg/L [p = 0.005] and a Mayo endoscopic subscore ≤1 [p = 0.0004] as factors associated with histological healing.

CONCLUSIONS

Histological healing was associated with higher vedolizumab trough levels during maintenance therapy in UC. A vedolizumab trough level threshold of 25 μg/mL proved most optimal to predict histological healing according to the Nancy histological index. Confirmation of these data in larger, independent cohorts is needed.

Proactive Therapeutic Drug Monitoring of Adalimumab Is Associated With Better Long-term Outcomes Compared With Standard of Care in Patients With Inflammatory Bowel Disease

BACKGROUND AND AIMS

Therapeutic drug monitoring [TDM] has proven to be effective for optimising anti-tumour necrosis factor [TNF] therapy in inflammatory bowel disease [IBD]. Nevertheless, the majority of data refer to infliximab and reactive testing or association studies. We aimed to compare the long-term outcome of patients with IBD who received at least one proactive TDM of adalimumab, with standard of care, defined as empirical dose escalation and/or reactive TDM.

METHODS

This was a multicentre retrospective cohort study. Patients on maintenance adalimumab therapy from June 2006 to December 2015 were eligible. We analysed time to treatment failure from start of adalimumab until the end of follow-up [July 2016]. Treatment failure was defined as drug discontinuation for secondary loss of response or serious adverse event or need for IBD-related surgery. Serum adalimumab concentrations and antibodies to adalimumab were measured using the Prometheus homogeneous mobility shift assay.

RESULTS

A total of 382 patients with IBD [Crohn's disease, n = 311, 81%] were included and received either at least one proactive TDM [n = 53] or standard of care [empirical dose escalation, n = 279; reactive TDM, n = 50]. Patients were followed for a median of 3.1 years [interquartile range, 1.4-4.8 years]. Multiple Cox regression analyses showed that at least one proactive TDM was independently associated with a reduced risk for treatment failure (hazard ratio [HR]: 0.4; 95% confidence interval [CI]: 0.2-0.9; p = 0.022).

CONCLUSIONS

This multicentre, retrospective cohort study reflecting real-life clinical practice provides the first evidence that proactive TDM of adalimumab may be associated with a lower risk of treatment failure compared with standard of care in patients with IBD.

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.

Actual Anti-TNF Trough Levels Relate to Serum IL-10 in Drug-Responding Patients With Crohn's Disease

BACKGROUND

Patients with Crohn's disease (CD) responding to anti-tumor necrosis factor (anti-TNF) show great variability in serum drug levels, even within the therapeutic range. We aimed at exploring the role of inflammatory, genetic, and bacterial variables in relation to anti-TNF through levels in CD patients.

METHODS

Consecutive CD patients receiving stable doses of infliximab or adalimumab were included. Clinical and analytical parameters were recorded. Cytokine response, bacterial DNA translocation, and several immune-related genes' genotypes were evaluated, along with serum through anti-TNF drug levels. A linear regression analysis controlled by weight and drug regimen was performed.

RESULTS

One hundred nineteen patients were initially considered. Five patients on infliximab and 2 on adalimumab showed antidrug antibodies in serum and were excluded. One hundred twelve patients were finally included (62 on infliximab, 50 on adalimumab). Fourteen patients on infliximab and 15 on adalimumab (22.6% vs 30%, P = 0.37) were receiving an intensified drug regimen. C-reactive protein (CRP), fecal calprotectin, Crohn's Disease Activity Index, leukocyte count, and albumin levels in plasma were not significantly associated with infliximab or adalimumab levels in the multivariate analysis. Serum interleukin-10 (IL-10) levels were directly related to infliximab (Beta = 0.097, P < 0.0001) and adalimumab levels (Beta = 0.069, P = 0.0241). The best multivariate regression model explaining the variability of serum infliximab and adalimumab levels included IL-10. Predicted drug levels by this model robustly fitted with actual drug levels (R2 = 0.841 for infliximab, R2 = 0.733 for adalimumab).

CONCLUSION

Serum IL-10 is significantly related to serum anti-TNF levels in CD patients, showing how the disposition of anti-TNF drugs is significantly influenced by the degree of immunological activation.

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.

Therapeutic drug monitoring with biologic agents in immune mediated inflammatory diseases

: Most exposure-response relationship studies show a positive correlation between biologic drug concentrations and favorable therapeutic outcomes in IMID with higher drug concentrations typically associated with more objective outcomes. Clinically, reactive TDM rationalizes the management of PNR and SLR to anti-tumor necrosis factor therapy and is emerging as the new standard of care in IBD as it is also more cost-effective than empiric dose escalation. Preliminary data suggest that proactive TDM with the goal to achieve a threshold drug concentration is associated with better therapeutic outcomes when compared to empiric drug optimization and/or reactive TDM of infliximab and adalimumab in IBD. However, more data from well-designed prospective studies are needed to prove the benefit of TDM-based algorithms in real life clinical practice in IMID.

Accuracy of the new rapid test for monitoring adalimumab levels

BACKGROUND

The loss of response to adalimumab (ADL) has been related to low serum concentrations at trough. Currently, most methods commercially available for the quantification of ADL are enzyme-linked immunosorbent assay (ELISA) based, with a turnaround time of approximately 8 h, delaying the target dosage adjustment to the subsequent infusion. In this study, we aimed to evaluate the performance of the newly available rapid-test ADL quantification assay by comparing it with three established ELISA methods, using spiked samples and a set of clinical samples.

METHODS

Spiked samples from control donors and 120 serum samples from inflammatory bowel disease (IBD) patients undergoing ADL therapy were quantified using lateral flow Quantum Blue^® Adalimumab and, the ELISA formats from Immundiagnostik, R-Biopharm and an in-house assay.

RESULTS

The rapid-test assay had intraclass correlation coefficients of 0.590, 0.864 and 0.761 when comparing with the Immundiagnostik, R-Biopharm and in-house assays, respectively. For the five therapeutic windows, the accuracy was high: ADL rapid test compared with the Immundiagnostik (58-88%); R-Biopharm, 68-89%; and in house, 60-88%; and kappa statistics revealed 0.492-0.602, 0.531-0.659 and 0.545-0.682, respectively.

CONCLUSIONS

The Quantum Blue^® Adalimumab assay can replace the commonly used ELISA-based ADL quantification kits and it is a reliable alternative to these methods. This rapid-test assay enables the quantitative determination of ADL serum trough level in only 15 min. The developed assay allows measurement of ADL over a wide range. Hence, it represents a valuable tool for the clinician to assess the ADL trough level.

Vedolizumab exposure levels and clinical outcomes in ulcerative colitis: determining the potential for dose optimisation

BACKGROUND

Prospectively designed studies assessing the exposure-response profile of vedolizumab are lacking. Observational exposure-response data for vedolizumab are limited and have not been adjusted for potential confounding factors, particularly those that may affect vedolizumab clearance.

AIMS

To (a) investigate the vedolizumab exposure-response relationship after adjusting for potential confounding variables; (b) propose potential target serum vedolizumab concentrations for future study; (c) ascertain whether early vedolizumab serum concentrations were associated with short- and long-term clinical outcomes in adults with ulcerative colitis in GEMINI 1.

METHODS

Propensity-score-based case-matching analysis was performed using data from GEMINI 1 and an earlier large population pharmacokinetic study, with vedolizumab clearance or concentration as predictors of clinical remission and response, adjusted for age, weight, anti-tumour necrosis factor alpha therapy history, serum albumin and faecal calprotectin concentrations. Potential vedolizumab concentration targets at weeks 6, 14 and steady state were proposed. Association between early vedolizumab concentrations at weeks 2, 4 and 6 and clinical remission at weeks 14 and 52 was evaluated.

RESULTS

Among 693 patients with pharmacokinetic data at week 6, potential target vedolizumab concentrations at weeks 6, 14 and steady state were 37.1, 18.4 and 12.7 µg/mL respectively. Week 6 was identified as the earliest time at which vedolizumab concentrations were consistently associated with clinical remission at weeks 14 and 52.

CONCLUSIONS

In this comprehensively adjusted analysis, vedolizumab concentrations at week 6 were associated with short- and long-term remission. Potential induction and maintenance target concentrations were proposed for further study.

Evaluating mucosal healing using colon capsule endoscopy predicts outcome in patients with ulcerative colitis in clinical remission

AIM

To examine whether second generation of colon capsule endoscopy (CCE-2) is acceptable for assessing the severity of mucosal inflammation and evaluating mucosal healing using CCE-2 is able to predict outcome in ulcerative colitis (UC) patients, especially in clinical remission.

METHODS

A total of 30 consecutive UC patients in clinical remission were enrolled to undergo CCE-2. Clinical remission was defined as clinical activity index (CAI) ≤ 4 according to Rachmilewitz index. The rate of total colon observation and colon cleansing level were evaluated. Severity of mucosal inflammation in UC was assessed according to the Mayo endoscopic subscore (MES) and Ulcerative Colitis Endoscopic Index of Severity (UCEIS). Relapse-free survival was assessed. Acceptability of CCE-2 was assessed using a questionnaire survey.

RESULTS

The rate of total colon observation within its battery life was 93.3%. The proportion of “excellent” plus “good” cleansing level was 73.3%. The rate of mucosal healing (MES 0, 1) assessed by CCE-2 was 77.0%. The relapse-free survival rate was significantly higher in MES 0, 1 than in MES 2, 3 (P = 0.0435), and in UCEIS 0-3 than in UCEIS 4-8 (P = 0.0211), whereas there was no significant difference between CAI 0 and CAI 1-4 groups. A questionnaire survey revealed an overall acceptability of CCE.

CONCLUSION

CCE-2 is acceptable for assessing the severity of mucosal inflammation in UC patients, especially in clinical remission. Evaluating mucosal healing using CCE-2 was able to predict outcome.

Maintenance Adalimumab Concentrations Are Associated with Biochemical, Endoscopic, and Histologic Remission in Inflammatory Bowel Disease

BACKGROUND

A treat-to-target therapeutic approach is emerging as the new standard of care for treating inflammatory bowel disease (IBD), Crohn's disease (CD), and ulcerative colitis (UC).

AIMS

We aimed to investigate the association of serum adalimumab concentrations during maintenance therapy with biochemical, endoscopic, and histologic remission in IBD.

METHODS

This retrospective multicenter study included consecutive IBD patients on adalimumab maintenance therapy who had a C-reactive protein (CRP) within 1 week and/or endoscopic evaluation within 12 weeks of therapeutic drug monitoring between July 2013 and December 2016. Biochemical remission was defined as a normal CRP (≤ 5 mg/L). Endoscopic remission was defined as the absence of any ulceration/erosion or a Rutgeerts score of ≤ i1 for patients with an ileocolonic resection for CD and a Mayo endoscopic score of ≤ 1 for UC. Histologic remission was defined as the absence of any sign of active inflammation. Adalimumab concentrations were measured using the homogeneous mobility shift assay.

RESULTS

Ninety-one CRP levels and 72 colonoscopies from 98 IBD patients [CD: n = 72 (73%)] were evaluated. Based on receiver operating characteristic analyses, we identified an adalimumab concentration threshold of 11.8, 12, and 12.2 μg/mL in CD and 10.5, 16.2, and 16.2 μg/mL in UC to stratify patients with or without biochemical, endoscopic, or histologic remission, respectively. Adalimumab concentrations ≥ 12 μg/mL (OR 8; 95% CI 2-31.9; p = 0.003) and ≥ 12.2 μg/mL (OR 9.6; 95% CI 1.7-56.1; p = 0.012) were independently associated with endoscopic and histologic remission in CD, respectively.

CONCLUSIONS

This study demonstrates that higher maintenance adalimumab concentrations are associated with objective therapeutic outcomes in IBD.

Wide variation in the use and understanding of therapeutic drug monitoring for anti-TNF agents in inflammatory bowel disease: an inexact science?

BACKGROUND

We aimed to understand the way in which therapeutic drug monitoring (TDM) is used, understood and interpreted for anti-TNF agents in IBD.

RESEARCH DESIGN AND METHODS

We designed an 18-question survey that included 5 TDM-based clinical scenarios, for which the 'most appropriate' responses were based on the BRIDGe groups 'Anti-TNF Optimizer'. This resource combines TDM evidence with expert consensus.

RESULTS

We received 110 complete responses: 50 (45%) consultants, 30 (27%) trainees, 25 (23%) IBD nurse specialists and 5 (5%) gastroenterology pharmacists. Over half (61, 55%) only carry out TDM in non-response. The remainder use TDM routinely, including during stable maintenance therapy for patients in remission. Lower therapeutic thresholds used were variable. Most (82, 75%) were unsure whether their laboratory uses a drug-tolerant or drug-sensitive antidrug antibody assay and few (15, 14%) understand the difference. Consultants, high-frequency users (> 3requests/month) and clinicians with larger anti-TNF cohorts (> 100) were significantly more likely to select the 'most appropriate' answer to at least 1 of the 5 TDM-based clinical scenarios.

CONCLUSIONS

There exists marked heterogeneity in the practical use, understanding and interpretation of biologic TDM. Biologic decision-making, informed by TDM, should involve consultation with experienced clinicians who are frequent TDM users, ideally, as part of a multidisciplinary, biologics-focused IBD meeting.

ABBREVIATIONS

TDM: therapeutic drug monitoring; CNS: clinical nurse specialist; ELISA: enzyme-linked immunosorbent assay; RIA: radioimmunoassays; HMSA: homogenous mobility shift assays; BSG: British Society of Gastroenterology.

Management of Paediatric Ulcerative Colitis, Part 1: Ambulatory Care-An Evidence-based Guideline From European Crohn's and Colitis Organization and European Society of Paediatric Gastroenterology, Hepatology and Nutrition

BACKGROUND

The contemporary management of ambulatory ulcerative colitis (UC) continues to be challenging with ∼20% of children needing a colectomy within childhood years. We thus aimed to standardize daily treatment of pediatric UC and inflammatory bowel diseases (IBD)-unclassified through detailed recommendations and practice points.

METHODS

These guidelines are a joint effort of the European Crohn's and Colitis Organization (ECCO) and the Paediatric IBD Porto group of European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN). An extensive literature search with subsequent evidence appraisal using robust methodology was performed before 2 face-to-face meetings. All 40 included recommendations and 86 practice points were endorsed by 43 experts in Paediatric IBD with at least an 88% consensus rate.

RESULTS

These guidelines discuss how to optimize the use of mesalamine (including topical), systemic and locally active steroids, thiopurines and, for more severe disease, biologics. The use of other emerging therapies and the role of surgery are also covered. Algorithms are provided to aid therapeutic decision-making based on clinical assessment and the Paediatric UC Activity Index (PUCAI). Advice on contemporary therapeutic targets incorporating the use of calprotectin and the role of therapeutic drug monitoring are presented, as well as other management considerations around pouchitis, extraintestinal manifestations, nutrition, growth, psychology, and transition. A brief section on disease classification using the PIBD-classes criteria and IBD-unclassified is also part of these guidelines.

CONCLUSIONS

These guidelines provide a guide to clinicians managing children with UC and IBD-unclassified management to provide modern management strategies while maintaining vigilance around appropriate outcomes and safety issues.

Anti-TNF Therapeutic Drug Monitoring in Postoperative Crohn's Disease

BACKGROUND

Anti-TNF prevents postoperative Crohn's disease recurrence in most patients but not all. This study aimed to define the relationship between adalimumab pharmacokinetics, maintenance of remission and recurrence.

METHODS

As part of a study of postoperative Crohn's disease management, some patients undergoing resection received prophylactic postoperative adalimumab. In these patients, serum and fecal adalimumab concentration and serum anti-adalimumab antibodies [AAAs] were measured at 6, 12 and 18 months postoperatively. Levels of Crohn's disease activity index [CDAI], C-reactive protein [CRP] and fecal calprotectin [FC] were assessed at 6 and 18 months postoperatively. Body mass index and smoking status were recorded. A colonoscopy was performed at 6 and/or 18 months.

RESULTS

Fifty-two patients [32 on monotherapy and 20 on combination therapy with thiopurine] were studied. Adalimumab concentration did not differ significantly between patients in endoscopic remission vs recurrence [Rutgeerts ≥ i2] [9.98µg/mL vs 8.43 µg/mL, p = 0.387]. Patients on adalimumab monotherapy had a significantly lower adalimumab concentration [7.89 µg/mL] than patients on combination therapy [11.725 µg/mL] [p = 0.001], and were significantly more likely to have measurable AAA [31% vs 17%, p = 0.001]. Adalimumab concentrations were lower in patients with detectable AAA compared with those without [3.59 µg/mL vs 12.0 µg/mL, p < 0.001]. Adalimumab was not detected in fecal samples. Adalimumab serum concentrations were lower in obese patients compared with in non-obese patients [p = 0.046].

CONCLUSION

Adalimumab concentration in patients treated with adalimumab to prevent symptomatic endoscopic recurrence postoperatively is, for most patients, well within the therapeutic window, and is not significantly lower in patients who develop recurrence compared with in those who remain in remission. Mechanisms of anti-TNF failure to prevent postoperative recurrence remain to be determined in these patients.

Early vedolizumab trough levels predict mucosal healing in inflammatory bowel disease: a multicentre prospective observational study

BACKGROUND

The correlation between vedolizumab trough levels during induction therapy and mucosal healing remains unknown.

AIM

To compare early vedolizumab trough levels in patients with and without mucosal healing within the first year after treatment initiation.

METHODS

We prospectively collected vedolizumab trough levels in all inflammatory bowel disease patients at weeks 2, 6 and 14 of vedolizumab treatment in three French referral centres between 1 June 2014 and 31 March 2017. Results of every patient that underwent mucosal assessment by magnetic resonance imaging and/or endoscopy in the first year after treatment initiation were analysed.

RESULTS

Median vedolizumab trough levels in the overall population (n = 82) were 27 μg/mL (interquartile range, IQR 21.2-33.8 μg/mL) at week 2, 23 μg/mL (IQR 15-34.5 μg/mL) at week 6 and 10.7 μg/mL (IQR 4.6-20.4 μg/mL) at week 14. Only median vedolizumab trough levels at week 6 differed between patients with and without mucosal healing within the first year after treatment initiation (26.8 vs 15.1 μg/mL, P = 0.035). A cut-off trough level of 18 μg/mL at week 6 predicted mucosal healing within the first year after the start of vedolizumab with an area under the receiver operating curve of 0.735 (95% confidence interval 0.531-0.939). A vedolizumab trough level above 18 μg/mL at week 6 was the only independent variable associated with mucosal healing within the first year of treatment (odds ratio 15.7, 95% confidence interval 2.4-173.0, P = 0.01).

CONCLUSION

Early therapeutic drug monitoring might improve timely detection of vedolizumab-treated patients in need for an intensified dosing regimen.

Subtherapeutic concentrations of infliximab and adalimumab are associated with increased disease activity in Crohn's disease

BACKGROUND

Low anti-tumor necrosis factor α (TNFα) serum concentrations may result in lack of treatment response in patients with inflammatory bowel disease. We determined the anti-TNFα drug concentrations in patients with inflammatory bowel disease and investigated whether or not subtherapeutic drug concentrations were associated with increased levels of disease activity.

METHODS

In a single-center cross-sectional study, we included patients with ulcerative colitis or Crohn's disease who were receiving infliximab or adalimumab maintenance therapy. Demographic data, disease activity symptom scores (Partial Mayo Score, Harvey Bradshaw Index), inflammatory markers [C-reactive protein (CRP), fecal calprotectin], antidrug antibodies and serum drug concentrations were recorded. Therapeutic drug concentrations were defined as 3-8 mg/liter for infliximab and 5-12 mg/liter for adalimumab.

RESULTS

Of 210 patients included, 137 (65.2%) had Crohn's disease. In the adalimumab group, subtherapeutic drug concentrations were measured in 16.7% of patients with ulcerative colitis and in 27.7% of patients with Crohn's disease. In the infliximab group, subtherapeutic drug concentrations were found in 23% (ulcerative colitis) and 30.3% (Crohn's disease) of patients. In Crohn's disease, subtherapeutic adalimumab concentrations were associated with higher fecal calprotectin and CRP concentrations compared with therapeutic concentrations. Subtherapeutic infliximab concentrations in patients with Crohn's disease were also associated with higher CRP concentrations compared with therapeutic concentrations.

CONCLUSIONS

The prevalence of subtherapeutic drug levels ranged from 17% to 30%. In patients with Crohn's disease, subtherapeutic serum drug concentrations were associated with significantly higher disease activity with both anti-TNFα agents. These findings were not observed in patients with ulcerative colitis. Clinicaltrials.gov identifier [NCT02134054].

Biological therapies in inflammatory bowel disease: Beyond anti-TNF therapies

The pharmacological management of inflammatory bowel disease (IBD) over the last two decades has transitioned from reliance on aminosalycilates, corticosteroids and immunomodulators to earlier treatment with anti-tumor necrosis factor (anti-TNF) therapy. Nevertheless, 20-30% of patients discontinue anti-TNF therapy for primary non-response and another 30-40% for losing response within one year of treatment. These undesirable therapeutic outcomes can be attributed to pharmacokinetic (anti-drug antibodies and/or low drug concentrations) or pharmacodynamic issues characterized by a non-TNF driven inflammation. The latter issues necessitate the use of medications with different mechanisms of action. Besides the biologics natalizumab, vedolizumab and ustekinumab that have already been approved for the treatment of IBD new non-anti-TNF therapies are currently under investigation including small molecule drugs against Janus kinase and sphingosine-1-phosphate receptors. This manuscript will review the medications that are in the later stages of development for the treatment of IBD and directed against immune targets other than TNF.

Infliximab trough concentrations during maintenance therapy are associated with endoscopic and histologic healing in ulcerative colitis

BACKGROUND

Endoscopic and histologic healing are emerging as new therapeutic goals in ulcerative colitis (UC), as these endpoints are associated with less relapse, hospitalization and colectomy.

AIM

To investigate the association of serum infliximab trough concentrations during maintenance therapy with endoscopic or histologic healing in UC.

METHODS

In this multi-center retrospective cohort study, we included consecutive patients with moderate-to-severe UC on infliximab maintenance therapy who had an endoscopic evaluation and underwent therapeutic drug monitoring within three months of the colonoscopy, between February 2008 and March 2016. Per event analysis was performed. Endoscopic healing was defined as Mayo endoscopic sub-score of ≤1. Histologic healing was defined as no or only focal mild active inflammation.

RESULTS

Seventy colonoscopies from 56 patients were evaluated. Infliximab trough concentrations (median [interquartile range]) were significantly higher in patients with endoscopic (11.3 [7.6-14.5] vs 6.3 [0-9.8] μg/mL, P < .001) or histologic (11.1 [6.7-14.5] vs 6.7 [0-9.9] μg/mL, P = .002) healing, respectively, compared to patients without healing. Receiver-operating characteristic analyses identified infliximab trough concentration thresholds of 7.5 (area under the curve [AUC]: 0.758) and 10.5 (AUC: 0.721) μg/mL to be associated with endoscopic and histologic healing, respectively. Multiple logistic regression analysis identified infliximab trough concentration ≥7.5 (P = .013; odds ratio [OR]: 4.3; 95% confidence intervals [CI]: 1.4-13.3) and ≥10.5 μg/mL (P = .013; OR: 3.8; 95% CI: 1.3-11) as independent factors associated with endoscopic and histologic healing, respectively.

CONCLUSIONS

This study demonstrated that infliximab trough concentrations during maintenance therapy are associated with endoscopic and histologic healing in patients with UC.

A Survey Study of Gastroenterologists' Attitudes and Barriers Toward Therapeutic Drug Monitoring of Anti-TNF Therapy in Inflammatory Bowel Disease

BACKGROUND

Therapeutic drug monitoring (TDM) may improve the efficacy and cost-effectiveness of anti-TNF therapy. A standardized approach of utilizing TDM has not been established. The objective of this study was to determine gastroenterologists' attitudes and barriers toward TDM of anti-TNF therapy in clinical practice.

METHODS

An 18-question survey was distributed to members of the American College of Gastroenterology and Crohn's and Colitis Foundation via email. We collected physician characteristics, practice demographics, and data regarding TDM use and perceived barriers to TDM. Factors associated with the use of TDM were determined by logistic regression analysis.

RESULTS

A total of 403 gastroenterologists from 42 US states (76.4% male) met inclusion criteria: 90.1% use TDM, mostly reactively for secondary loss of response (87.1%) and primary nonresponse (66%); 36.6% use TDM proactively. The greatest barriers to TDM implementation were uncertainty about insurance coverage (77.9%), high out-of-pocket patient costs (76.4%), and time lag from serum sample to result (38.5%). Factors independently associated with the use of TDM and proactive TDM were practice in an academic setting (P = 0.019), and more IBD patients seen per month (P = 0.015), and Crohn's and Colitis Foundation membership (P < 0.001), and more IBD patients on anti-TNF therapy per month (P = 0.006), respectively. If all barriers were removed, an additional one-third of physicians would apply proactive TDM.

CONCLUSIONS

Lack of insurance coverage, high out-of-pocket costs, and the time lag from test to result limit use of TDM in the United States. Validation of low-cost assays, point of care testing, and studies that standardize the use of TDM are needed to make TDM more commonplace.

Out-of-Pocket Cost Is a Barrier to Therapeutic Drug Monitoring in Inflammatory Bowel Disease

BACKGROUND

Therapeutic drug monitoring (TDM) is increasingly performed to optimize biologic therapy in inflammatory bowel disease (IBD). However, patients and physicians may be reluctant to perform TDM due to concerns related to potential out-of-pocket costs.

AIMS

The aim of this study was to evaluate patient understanding and attitudes toward TDM in different clinical scenarios with and without potential out-of-pocket costs.

METHODS

Adult IBD patients at a tertiary gastroenterology clinic were anonymously surveyed from March to September 2016 to assess their understanding of and willingness to undergo TDM in a variety of clinical scenarios, both with and without a potential out-of-pocket cost. Responses were analyzed for associations with changes in attitudes if out-of-pocket costs were involved.

RESULTS

Of 118 completed surveys, 68.2% of patients were aware of or had previously undergone TDM. Patient willingness to undergo TDM was high both with and without potential out-of-pocket costs (70 and 98%, respectively); however, patients were significantly less willing with out-of-pocket cost (p < 0.01). Higher disease-related quality of life scores, as measured by the short inflammatory bowel disease questionnaire (SIBDQ), was significantly associated with an increased willingness to assume a potential out-of-pocket cost (p = 0.007).

CONCLUSIONS

Overall, patients understand and are willing to undergo TDM in certain potentially beneficial clinical scenarios, however, are significantly less willing if paying out-of-pocket. A higher SIBDQ score was associated with an increase in willingness to undergo TDM when out-of-pocket cost was involved. Physicians should discuss TDM with their patients in order to make an informed and personalized treatment decision.

Improved Long-term Outcomes of Patients With Inflammatory Bowel Disease Receiving Proactive Compared With Reactive Monitoring of Serum Concentrations of Infliximab

BACKGROUND & AIMS

Monitoring serum concentrations of tumor necrosis factor antagonists in patients receiving these drugs as treatment for inflammatory bowel disease (IBD), also called therapeutic drug monitoring, is performed either after patient loss of response (reactive drug monitoring) or in patients in clinical remission in which the drug is titrated to a target concentration (proactive drug monitoring). We compared long-term outcomes of patients with IBD undergoing proactive vs reactive monitoring of serum concentrations of infliximab.

METHODS

We performed a multicenter, retrospective study of 264 consecutive patients with IBD (167 with Crohn's disease) receiving infliximab maintenance therapy. The subjects received proactive (n = 130) or reactive (n = 134) drug monitoring, based on measurements of first infliximab concentration and antibodies to infliximab, from September 2006 to January 2015; they were followed through December 2015 (median time of 2.4 years). We analyzed time to treatment failure, first IBD-related surgery or hospitalization, serious infusion reaction, and detection of antibodies to infliximab. Treatment failure was defined as drug discontinuation for loss of response or serious adverse event, or need for surgery.

RESULTS

Multiple Cox regression analysis independently associated proactive drug monitoring, compared with reactive monitoring, with reduced risk for treatment failure (hazard ratio [HR], 0.16; 95% confidence interval [CI], 0.09-0.27; P < .001), IBD-related surgery (HR, 0.30; 95% CI, 0.11-0.80; P = .017), IBD-related hospitalization (HR, 0.16; 95% CI, 0.07-0.33; P < .001), antibodies to infliximab (HR, 0.25; 95% CI, 0.07-0.84; P = .025), and serious infusion reaction (HR, 0.17; 95% CI, 0.04-0.78; P = .023).

CONCLUSIONS

In a retrospective analysis of patients with IBD receiving proactive vs reactive monitoring of serum concentration of infliximab, proactive monitoring was associated with better clinical outcomes, including greater drug durability, less need for IBD-related surgery or hospitalization, and lower risk of antibodies to infliximab or serious infusion reactions.