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

Mirikizumab Exposure-Response Relationships in Patients with Moderately-to-Severely Active Ulcerative Colitis in Randomized Phase II and III Studies

Mirikizumab is a humanized anti-interleukin-23p19 monoclonal antibody being developed for ulcerative colitis (UC) and Crohn's disease. We characterized the relationship of mirikizumab systemic exposure with efficacy and safety end points in patients with UC using phase II (NCT02589665) and III (NCT03518086, NCT03524092) trial data. Exposure-response models were developed for clinical remission, clinical response, endoscopic remission, and change in modified Mayo score following induction (50-1,000 mg i.v. every 4 weeks) and maintenance (200 mg s.c. every 4 or 12 weeks) treatment. These models evaluated observed and pharmacokinetic model-predicted mirikizumab exposures as the exposure measure. Key safety event rates were compared across mirikizumab exposure quartiles in the phase III trial. Mirikizumab efficacy in patients with UC showed an apparent positive association with systemic exposure following both induction and maintenance. However, further analysis found this relationship to be overstated by the presence of confounding factors that were not among the tested patient covariates. While prior biologic experience and baseline disease severity showed statistically significant influences on estimated placebo effect, no patient factors affected the mirikizumab effect parameters in any of the phase III exposure-response models. There was no apparent mirikizumab concentration relationship with any adverse event of special interest. When the phase II and III data and confounding are considered together, efficacy was unlikely to be strongly affected by variation in exposures across individual patients at the phase III dose. Together with the previously demonstrated mirikizumab exposure insensitivity to patient factors, these findings indicate that mirikizumab dose adjustment to patient characteristics is not required.

Proactive Therapeutic Drug Monitoring Is Associated With Increased Drug Persistence in Patients With Inflammatory Bowel Disease Treated With Intravenous Vedolizumab

BACKGROUND

There are limited data regarding therapeutic drug monitoring (TDM) of non-anti-tumor necrosis factor therapy in inflammatory bowel disease (IBD). This study aimed to evaluate the efficacy of proactive TDM in IBD patients treated with intravenous (iv) vedolizumab (VDZ).

METHODS

This single-center retrospective cohort study included consecutive IBD patients treated with maintenance iv VDZ therapy undergoing TDM from November 2016 to March 2023. Patients were followed through June 2023 and were divided in to 2 groups: those who had at least 1 proactive TDM vs those who underwent only reactive TDM. A survival analysis was performed to evaluate drug persistence, defined as no need for drug discontinuation due to loss of response, serious adverse event, or an IBD-related surgery.

RESULTS

The study population consisted of 94 patients (proactive TDM, n = 72) with IBD (ulcerative colitis, n = 53). Patients undergoing at least 1 proactive TDM compared with patients having only reactive TDM demonstrated a higher cumulative probability of drug persistence (Log-rank P < .001). In multivariable Cox proportional hazard regression analysis, at least 1 proactive TDM was the only factor associated with drug persistence (hazard ratio, 14.3; 95% confidence interval [CI], 3.8-50; P < .001). A ROC analysis identified a VDZ concentration of 12.5 µg/mL as the optimal drug concentration threshold associated with drug persistence (area under the ROC curve: 0.691; 95% CI, 0.517-0.865; P = .049).

CONCLUSION

In this single-center retrospective study reflecting real-life clinical practice, proactive TDM was associated with increased drug persistence in patients with IBD treated with iv VDZ.

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

Comparing the efficacy of vedolizumab between males and females: a post-hoc analysis of GEMINI-1 and VARSITY

Vedolizumab is a first-line treatment option for ulcerative colitis. There are differences in incidence of ulcerative colitis between males and females, but whether sex affects treatment outcomes is less clear. We examined sex-based differences in patients with ulcerative colitis initiated on vedolizumab from two major randomized controlled trials (RCTs). We conducted a post-hoc analysis on participants with ulcerative colitis from the VARSITY and GEMINI-1 RCTs who received vedolizumab. Outcomes of interest were rates of clinical improvement, clinical remission, and endoscopic improvement at weeks 6, 14, and 52 in male and female participants, as were differences in concentrations of trough vedolizumab and C-reactive protein; 1009 persons in GEMINI-1 and VARSITY trials were included. Male and female patients had similar disease characteristics aside from males being more likely to have Mayo 3 grade endoscopic severity at baseline (62.8 vs. 48.9%, P  < 0.001). At week 6, females were more likely to have endoscopic improvement (47.4 vs. 35.2%, P  = 0.001) and increased vedolizumab trough levels [34.0 (23.0-44.5) vs. 28.9 (19.0-34.6), P  < 0.001]. The probability of achieving clinical remission (28.9 vs. 34.5%, P  = 0.057) or endoscopic improvement (35.5 vs. 39.3%, P  = 0.212) at week 52 was not different between males and females. Females with ulcerative colitis treated with vedolizumab appear more likely to achieve early endoscopic improvement than males, though longer-term outcomes demonstrated no difference. Further studies are required to better understand mechanisms through which sex or sex-associated factors could influence response to therapy in ulcerative colitis.

Evaluation of the transition from intravenous to subcutaneous vedolizumab in patients with inflammatory bowel disease

AIMS

The aim of the study is to evaluate the clinical and biochemical response of inflammatory bowel disease patients treated with vedolizumab, 16 weeks after transitioning from intravenous (iv) to subcutaneous (sc).

METHODS

An observational, prospective, single-center cohort study was performed. Patients with inflammatory bowel disease and maintenance treatment with vedolizumab, stable for at least 4 months, were offered to switch to sc formulation. At the same time of treatment administration a blood test was performed, with vedolizumab levels and fecal calprotectin.

RESULTS

Forty-three patients were included, 12 of them (27.9%) chose to transition to sc formulation. All included patients remained in remission during follow-up. At week 16 no significant differences were found in terms of calprotectin levels in patients on iv treatment (mean 146.6±SD 45.9) vs. sc (159.26±53.9) (p=0.9). Vedolizumab serum levels at week 16 were higher in the sc group (22,364.3±5141.6) vs. iv (11,425.9±1514.2) (p=0.009). At week 16, 9 (75%) of the patients in the sc group were highly satisfied with the medication and 11 (91.7%) considered it easy to administer. Four patients (12.9%) in the iv group and 2 (16.6%) in the sc group presented mild adverse effects. The 2 cases (100%) of the sc group the adverse event was local inflammation at the injection site.

CONCLUSION

In our experience, vedolizumab sc is a convenient alternative to iv administration. Vedolizumab serum levels in patients who transitioned to sc were higher than iv formulation.

ENTERPRET: A Randomized Controlled Trial of Vedolizumab Dose Optimization in Patients With Ulcerative Colitis Who Have Early Nonresponse

BACKGROUND & AIMS

Patients with ulcerative colitis (UC) may experience nonresponse to biologics, possibly as a result of low drug exposure. This trial assessed the efficacy of dose optimization in patients with UC who have early nonresponse to vedolizumab and high drug clearance.

METHODS

ENTERPRET was a phase 4, open-label, randomized, controlled trial that included patients with moderate to severe UC who had high drug clearance at week 5 (serum concentration, <50 μg/mL) and nonresponse to standard vedolizumab treatment at week 6. At week 6, eligible patients were randomized 1:1 to receive standard dosing (300 mg every 8 weeks) or dose-optimized vedolizumab (600 mg at week 6, then 300 mg every 4 weeks; or 600 mg at week 6, then 600 mg every 4 weeks [based on week 5 serum concentration]). The primary end point was endoscopic improvement at week 30.

RESULTS

Of 278 enrolled patients, 132 (47.5%) had a clinical response at week 6. From week 6, 108 patients received standard (n = 53) or dose-optimized vedolizumab (n = 55); among patients with nonresponse at week 6, 86.5% had high drug clearance. At week 30, 10 patients (18.9%) who received standard vedolizumab had endoscopic improvement vs 8 patients (14.5%) who received dose-optimized vedolizumab. Five patients (9.4%) who received standard vedolizumab had clinical remission at week 30 vs 5 patients (9.1%) who received dose-optimized vedolizumab; clinical response was observed in 17 (32.1%) and 17 patients (30.9%), respectively. Safety event rates were similar among treatment groups.

CONCLUSIONS

In patients with early nonresponse and high drug clearance, vedolizumab dose optimization is probably not required. A proportion of patients benefited from continued treatment irrespective of the dose received.

CLINICALTRIALS

gov: NCT03029143.

Exposure-efficacy relationship of vedolizumab subcutaneous and intravenous formulations in Crohn's disease and ulcerative colitis

BACKGROUND AND AIMS

This posthoc analysis of the GEMINI and VISIBLE studies in ulcerative colitis (UC) and Crohn's Disease (CD) assessed exposure-efficacy of vedolizumab intravenous (IV) and subcutaneous (SC).

METHODS

A previously described population pharmacokinetic model was used to predict average serum and trough concentrations at steady state (Cav,ss, Ctrough,ss) and simulate the transition from vedolizumab IV to SC. Efficacy was defined as clinical remission at week 52: complete Mayo score ≤ 2 points and no individual subscore > 1 point (UC), and CD activity index score ≤ 150 points (CD).

RESULTS

Data were from 1968 patients (GEMINI 1 [n = 334], VISIBLE 1 [n = 216], GEMINI 2 [n = 1009], VISIBLE 2 [n = 409]) who received maintenance treatment with vedolizumab IV-Q8W, IV-Q4W, SC-Q2W, or placebo. Model-predicted Cav,ss for IV-Q8W and SC-Q2W was similar in UC and CD. Cav,ss was higher for IV-Q4W than IV-Q8W and SC-Q2W. Ctrough,ss values from IV and SC aligned well with pooled observed Ctrough by treatment group in UC and CD. Cav,ss was equivalent for SC and IV. For UC and CD, efficacy rates were greater in patients in the highest quartiles of vedolizumab exposure for both formulations.

CONCLUSION

Exposure-efficacy relationships for IV and SC vedolizumab administration were comparable, confirming that both are equally effective during maintenance treatment.

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.

Precision medicine in inflammatory bowel disease

Inflammatory bowel disease (IBD) is an incurable disease characterized by remission-relapse cycles throughout its course. Both Crohn's disease (CD) and ulcerative colitis (UC), the two main forms of IBD, exhibit tendency to develop complications and substantial heterogeneity in terms of frequency and severity of relapse, thus posing great challenges to the clinical management for IBD. Current treatment strategies are effective in different ways in induction and maintenance therapies for IBD. Recent advances in studies of genetics, pharmacogenetics, proteomics and microbiome provide a strong driving force for identifying molecular markers of prognosis and treatment response, which should help clinicians manage IBD patients more effectively, and then, improve clinical outcomes and reduce treatment costs of patients. In this review, we summarize and discuss precision medicine in IBD, focusing on predictive markers of disease course and treatment response, and monitoring indices during therapeutic drug monitoring.

Understanding the molecular mechanisms of anti-trafficking therapies and their clinical relevance in inflammatory bowel disease

In patients with inflammatory bowel disease (IBD), a combination of dysbiosis, increased intestinal permeability, and insufficient regulatory responses facilitate the development of chronic inflammation, which is driven by a complex interplay between the mucosal immune system and the environment and sustained by immune priming and ongoing cellular recruitment to the gut. The localization of immune cells is mediated by their expression of chemokine receptors and integrins, which bind to chemokines and adhesion molecules, respectively. In this article, we review the mechanisms of action of anti-trafficking therapies for IBD and consider clinical observations in the context of the different mechanisms of action. Furthermore, we discuss the evolution of molecular resistance to anti-cytokines, in which the composition of immune cells in the gut changes in response to treatment, and the potential implications of this for treatment sequencing. Lastly, we discuss the relevance of mechanism of action to combination therapy for IBD.

Drug Clearance in Patients with Inflammatory Bowel Disease Treated with Biologics

Biological therapy is very effective for treating patients with moderate to severe inflammatory bowel disease (IBD). However, up to 40% can have primary non-response, and up to 50% of the patients can experience a loss of response to anti-tumor necrosis factor therapy. These undesirable outcomes can be attributed to either a mechanistic failure or pharmacokinetic (PK) issues characterized by an inadequate drug exposure and a high drug clearance. There are several factors associated with accelerated clearance of biologics including increased body weight, low serum albumin and immunogenicity. Drug clearance has gained a lot of attention recently as cumulative data suggest that there is an association between drug clearance and therapeutic outcomes in patients with IBD. Moreover, clearance is used by model informed precision dosing (MIDP) tools, or PK dashboards, to adjust the dosing for reaching a target drug concentration threshold towards a more personalized application of TDM. However, the role of drug clearance in clinical practice is yet to be determined. This comprehensive review aims to present data regarding the variables affecting the clearance of specific biologics, the association of clearance with therapeutic outcomes and the role of clearance monitoring and MIPD in patients with IBD.

Recruitment and Residence of Intestinal T Cells - Lessons for Therapy in Inflammatory Bowel Disease

Targeting leukocyte trafficking in the management of inflammatory bowel disease [IBD] has been a significant therapeutic advance over the past 15 years. However, as with other advanced therapies, phase III clinical trials report response to trafficking inhibitors in only a proportion of patients, with fewer achieving clinical remission or mucosal healing. Additionally, there have been significant side effects, most notably progressive multifocal leukoencephalopathy in association with the α4 inhibitor natalizumab. This article reviews the mechanisms underpinning T cell recruitment and residence, to provide a background from which the strength and limitations of agents that disrupt leukocyte trafficking can be further explored. The therapeutic impact of trafficking inhibitors is underpinned by the complexity and plasticity of the intestinal immune response. Pathways essential for gut homing in health may be bypassed in the inflamed gut, thus providing alternative routes of entry when conventional homing molecules are targeted. Furthermore, there is conservation of trafficking architecture between proinflammatory and regulatory T cells. The persistence of resident memory cells within the gut gives rise to local established pro-inflammatory populations, uninfluenced by inhibition of trafficking. Finally, trafficking inhibitors may give rise to effects beyond the intended response, such as the impact of vedolizumab on innate immunity, as well as on target side effects. With significant research efforts into predictive biomarkers already underway, it is ultimately hoped that a better understanding of trafficking and residence will help us predict which patients are most likely to respond to inhibition of leukocyte trafficking, and how best to combine therapies.

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.

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.

Real world population pharmacokinetic study in children and young adults with inflammatory bowel disease discovers novel blood and stool microbial predictors of vedolizumab clearance

BACKGROUND

Vedolizumab for inflammatory bowel disease (IBD) is often intensified based on distinct pharmacokinetics in children. Prior adult-specific population pharmacokinetic models have identified limited covariates of drug clearance.

AIMS

To establish a population pharmacokinetic model for children and young adults to identify novel covariates of drug clearance to better account for paediatric-specific inter-patient variability in vedolizumab pharmacokinetics; a key secondary exploratory aim was to identify microbial signatures of pharmacokinetic outcomes in a subset of patients.

METHODS

The study included data from 463 observed vedolizumab concentrations (59 peaks and 404 troughs) from 74 patients with IBD (52 with Crohn's disease and 22 with ulcerative colitis or unclassified IBD, median age 16 years). Pharmacokinetic analysis was conducted with non-linear mixed effects modelling. For the evaluation of the exposure-response relationship, clinical outcomes were evaluated by trough levels, clearance and vedolizumab exposure. Whole-genome metagenomic sequencing was conducted at baseline and week 2.

RESULTS

A two-compartment population pharmacokinetic model was identified with a clear correlation between CL and weight, erythrocyte sedimentation rate, and hypoalbuminemia. Trough concentrations before infusion 3 (37 μg/ml) and before infusion 4 (20 μg/ml) best predicted steroid-free clinical remission at infusion 4. Using faecal metagenomics, we identified an early (baseline and week 2) abundance of butyrate-producing species and pathways that were associated with an infusion 4 trough concentration >20 μg/ml.

CONCLUSIONS

This novel paediatric vedolizumab pharmacokinetic model could inform precision dosing. While additional studies are needed, an abundance of faecal butyrate producers is associated with early response to vedolizumab, suggesting that microbial analysis may be beneficial to biological selection.

The use of therapeutic drug monitoring for early identification of vedolizumab response in Saudi Arabian patients with inflammatory bowel disease

Vedolizumab is a humanized monoclonal antibody used to treat moderate-to-severe inflammatory bowel disease (IBD). The aim of the study was to assess the effectiveness of the induction of vedolizumab trough level in predicting short-term (week 14) clinical outcomes, and covariates that affect the response in Saudi Arabian patients. This prospective, real-life study included a total of 16 patients (4 Crohn's disease (CD) and 12 ulcerative colitis (UC)) with a confirmed diagnosis of IBD and generally naïve to receiving vedolizumab therapy. Using ELISA assay, vedolizumab induction trough and peak levels were measured at weeks 0, 2, and 6. The follow-up assessment was at week 14, where clinical outcomes were measured using the partial Mayo score for UC, and the CD activity score (CDAI), and Harvey Bradshaw index (HBI) for CD. At week 14, 9 patients (52.9%) out of 16 patients demonstrated response to therapy; clinical remission was reported in 5 patients (29.4%), and in 4 cases a clinical response was noted (23.5%). Clinical remission at week 14 was linked significantly with week 6 median vedolizumab levels in responders (25.1 µg/ml 95% CI: 16.5-42.9) compared to non-responders (7.7 µg/ml, 95% CI: 4.6-10.6) (P = 0.002). Receiver operator curve analysis at week 6 identified a cut-off > 8.00 µg/mL for short-term clinical remission. Also, at week 14, BMI significantly correlated with week 6 vedolizumab trough levels (P = 0.02). No other covariates correlated with drug levels at any time point examined. Week 6 early vedolizumab trough level measurements in IBD patients predicted short-term week 14 clinical remission.

Therapeutic Drug Monitoring in Practice for Inflammatory Bowel Disease

PURPOSE OF REVIEW

To outline the development, rationale, and practical use of therapeutic drug monitoring in patients with inflammatory bowel disease.

RECENT FINDINGS

Therapeutic drug monitoring is traditionally discussed in terms of a proactive or reactive approach. However, these terms are not always consistently defined and can be confusing when translating research to clinical practice. Personalized approaches incorporating clinical context and precision medicine are emerging. Personalized therapeutic drug monitoring combines a structured and proactive strategy for monitoring biologic concentrations as well as identification of antidrug antibody development or subtherapeutic dosing in the setting of loss of response. Optimizing biologic therapy can improve outcomes and avoid loss of response. Why, when, and how we measure drug troughs and anti-drug antibodies is a moving target, though what is known is that the appropriate and evidence-based use of this practice prevents adverse events and improves outcomes in patients with inflammatory bowel disease.

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.

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.

Therapeutic drug monitoring in inflammatory bowel disease treatments

Recently, biological drugs have played a leading role in the treatment of inflammatory bowel disease, and therapeutic drug monitoring (TDM) may be useful in maximizing their effectiveness. TDM involves the measurement of serum drug and anti-drug antibodies concentrations as the basis for dosage adjustments or drug conversions to achieve a higher response rate. We believe that concentration thresholds should be individualized based on patients’ disease severity, extent and phenotype, and therapeutic purposes should also be considered, with higher cut-offs mainly needed for endoscopic and fistula healing than for symptomatic remission. Proactive and reactive TDM can help optimize treatment, especially in patients receiving anti-tumour necrosis factor, and guide dose adjustment or drug conversion with lower cost. TDM is a promising approach to achieve precision medicine and targeted medicine in the future.

Patient-led Remote IntraCapillary pharmacoKinetic Sampling (fingerPRICKS) for Therapeutic Drug Monitoring in patients with Inflammatory Bowel Disease

BACKGROUND AND AIMS

Because of COVID-19 public health restrictions, telemedicine has replaced conventional outpatient follow up for most patients with chronic immune-mediated inflammatory disorders treated with biologic drugs. Innovative solutions to facilitate remote therapeutic drug monitoring are therefore required. Low-volume intracapillary blood sampling can be undertaken by patients at home and samples returned by post to central laboratories. We sought to report the effect of the COVID-19 pandemic on requests for therapeutic drug monitoring and the equivalence, acceptability and effectiveness of low volume Patient-led Remote IntraCapillary pharmacoKinetic Sampling [fingerPRICKS] compared to conventional venepuncture.

METHODS

We undertook a cross-sectional blood sampling methods comparison study and compared sample types using linear regression models. Drug and antidrug antibody levels were measured using standard ELISAs. Acceptability was assessed using a purpose-designed questionnaire.

RESULTS

Therapeutic drug monitoring requests for adalimumab (96.5 [70.5-106] per week to 52 [33.5-57.0], p < 0.001) but not infliximab (184.5 [161.2-214.2] to 161 [135-197.5], p = 0.34) reduced during the first UK stay-at-home lockdown compared with the preceding 6 months. Fingerprick sampling was equivalent to conventional venepuncture for adalimumab, infliximab, vedolizumab and ustekinumab drug, and anti-adalimumab and anti-infliximab antibody levels. The median [interquartile range] volume of serum obtained using intracapillary sampling was 195 µL [130-210]. More than 87% [90/103] of patients agreed that intracapillary testing was easy and 69% [71/103] preferred it to conventional venepuncture. In routine care, 75.3% [58/77] of patients returned two blood samples within 14 days to permit remote assessment of biologic therapeutic drug monitoring.

CONCLUSIONS

Therapeutic drug monitoring can be undertaken using patient-led remote intracapillary blood sampling and has the potential to be a key adjunct to telemedicine in patients with immune-mediated inflammatory diseases.

Therapeutic drug monitoring of biologics in inflammatory bowel disease: unmet needs and future perspectives

Therapeutic drug monitoring (TDM) has emerged as a useful tool for optimising the use of biologics, and in particular anti-tumour necrosis factor (anti-TNF) therapy, in inflammatory bowel disease (IBD). However, challenges remain and are hindering the widespread implementation of TDM in clinical practice. These barriers include identification of the optimal drug concentration to target, the lag time between sampling and results, and the proper interpretation of anti-drug antibody titres among different assays. Solutions to overcome these barriers include the harmonisation of TDM assays and the use of point-of-care testing. Other unmet needs include well designed prospective studies and randomised controlled trials focusing on proactive TDM, particularly during induction therapy. Future studies should also investigate the utility of TDM for biologics other than anti-TNF therapies in both IBD and other immune-mediated inflammatory diseases such as rheumatoid arthritis and psoriasis, and the use of pharmacokinetic modelling dashboards and pharmacogenetics towards individual personalised medicine.

Proposed pathway for therapeutic drug monitoring and dose escalation of vedolizumab

Vedolizumab is a gut-selective monoclonal antibody approved for the management of Crohn's disease and ulcerative colitis. The available data demonstrate a favourable response to dose escalation in patients with primary non-response or secondary loss of response to vedolizumab. While therapeutic drug monitoring has a proven clinical utility for tumour necrosis factor antagonists, the available guidance for therapeutic drug monitoring and dose escalation of vedolizumab is rather limited. The present review proposes a practical algorithm to use vedolizumab trough levels in the management of treatment failure. Therapeutic drug monitoring can differentiate underexposed patients from those with mechanistic failure. Underdosed patients can respond to dose escalation instead of unnecessarily switching to other treatment modalities. We also review the safety and potential cost-effectiveness of vedolizumab dose escalation, the role of antidrug antibodies and the possible applicability of this strategy to subcutaneous vedolizumab.

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.

Transitioning from Intravenous to Subcutaneous Vedolizumab in Patients with Inflammatory Bowel Disease [TRAVELESS]

BACKGROUND AND AIMS

Subcutaneous [SC] vedolizumab presents the opportunity for inflammatory bowel disease [IBD] patients to manage their treatment at home. There are currently no data on the process of transitioning patients established on intravenous [IV] to SC vedolizumab as part of routine clinical care. The aim of this programme is to evaluate the clinical and biochemical outcomes of switching a cohort of IBD patients established on IV vedolizumab to SC, at 12 weeks following the transition.

METHODS

In all, 178 adult patients were offered the opportunity to transition to SC vedolizumab. Patients who agreed were reviewed prior to switching and at Week 12 [W12] after their first SC dose. Evaluation outcomes included disease activity scores, the IBD-Control Patient-Reported Outcome Measures [PROMs], and faecal calprotectin [FCP]. Reasons for patients declining or accepting transitioning, pharmacokinetics, adverse drug reactions, and risk factors for a poor outcome in SARS-CoV-2 infection were also assessed.

RESULTS

A total of 124 patients agreed to transition, of whom 106 patients had been on IV vedolizumab for at least 4 months. There were no statistically significant differences in disease activity scores or IBD-Control PROMs between baseline and W12. A statistically significant increase in FCP was observed [31 µg/g vs. 47 µg/g; p = 0.008], although this was unlikely to be clinically relevant. The most common adverse drug reaction reported was injection site reactions [15%]. Based on this cohort of patients, an expected reduction of £572,000 per annum is likely to be achieved.

CONCLUSIONS

Transitioning patients established on IV vedolizumab to SC appears to be safe and effective, with high patient satisfaction and multiple benefits for the health service.

A Practical Guide to Therapeutic Drug Monitoring of Biologic Medications for Inflammatory Bowel Disease

Therapeutic drug monitoring (TDM) is a useful strategy to optimize biologic medications for inflammatory bowel disease not responsive to standard dosing regimens. TDM is cost effective for anti-tumor necrosis factor agents in the setting of loss of response (reactive TDM). Optimizing drug dosing when patients are in remission (proactive TDM) may be beneficial in certain circumstances. However, frequently the serum drug concentration in isolation becomes the focus TDM. Additionally, the lines of reactive and proactive TDM can quickly blur in many common clinical settings. Physicians employing a TDM based strategy need to place the drug concentration in context with the inflammatory status of the patient, the underlying pharmacokinetics and pharmacodynamics of the drug, the risk of immunogenicity, and the therapeutic goals for the patient. Physicians should understand the limits of TDM and feel comfortable making therapeutic decisions with imperfect information. The goal of this narrative review is to provide a framework of questions that physicians can use to employ TDM effectively in practice.

Dose optimisation for Loss of Response to Vedolizumab- Pharmacokinetics and Immune Mechanisms

BACKGROUND

Real life data regarding pharmacokinetics of vedolizumab in patients needing dose optimisation are scarce. We set to examine whether pre-optimisation vedolizumab levels associate with therapy outcomes and which mechanisms explain the associations.

METHODS

A multicentre observational study assessed the outcome of dose increase in association with pre-escalation levels in vedolizumab-treated patients. SubsequentIy, α4β7 occupancy on peripheral blood [PB] and intestinal lamina propria [LP] tissues was investigated on various cellular subsets in patients undergoing lower endoscopy on infusion day. Cellular localisation of vedolizumab-bound α4β7 and effects on M1 and M2 macrophages were also explored.

RESULTS

A total of 161 inflammatory bowel disease [IBD] patients were included. Among 129/161 patients intensified during maintenance [Week 14 onward], pre-intensification trough levels were comparable or higher among those subsequently attaining post-optimisation clinical, biomarker, and endoscopic remission, compared with non-remitting patients [p = 0.09, 0.25, 0.04, respectively]. Similar results were demonstrated for those dose-optimised during induction [Week 6, n = 32]. In the immune sub-study [n = 43], free α4β7 receptors at trough were similarly low among patients with/without mucosal healing, on PB T cells [p = 0.15], LP T cells [p = 0.88], and on PB eosinophils [p = 0.08]. Integrin receptors on M1 and M2 macrophages were also saturated by low levels of vedolizumab and anti-inflammatory cytokine secretion was not increased. Co-localisation and dissociation experiments demonstrated membranal α4β7 receptors of two origins: non-internalised and newly generated α4β7, but re-binding was still complete at very low concentrations.

CONCLUSIONS

These results do not support pharmacokinetics as the mechanism responsible for loss of response to vedolizumab, nor do they support a need for higher drug concentration to enhance vedolizumab's immune effects. Higher pre-escalation levels may indicate less clearance [less severe disease] and higher likelihood of subsequent re-gained response, regardless of therapy escalation.

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.

Preoperative Serum Vedolizumab Levels Do Not Impact Postoperative Outcomes in Inflammatory Bowel Disease

BACKGROUND

Vedolizumab has been proposed to lead to fewer postoperative complications because of its gut specificity. Studies, however, suggest an increased risk of surgical site infections, yet the data are conflicting.

OBJECTIVE

This study aimed to assess the effect of vedolizumab drug levels on postoperative outcomes in patients undergoing major abdominal surgery for IBD.

DESIGN

This was a retrospective study of a prospectively maintained database.

SETTING

Patients were operated on by a single surgeon at an academic medical center.

PATIENTS

A total of 72 patients with IBD undergoing major abdominal surgery were included.

INTERVENTIONS

Patients were exposed preoperatively to vedolizumab.

MAIN OUTCOME MEASURES

The primary outcome measured was the postoperative morbidity in patients who had IBD with detectable vs undetectable vedolizumab levels.

RESULTS

A total of 72 patients were included in the study. Thirty-eight patients had detectable vedolizumab levels (>1.6 μg/mL), and 34 had undetectable vedolizumab levels. The overall rate of complications was 39%, and ileus was the most common complication. There were no significant differences in clinical variables between the detectable and undetectable vedolizumab level patient groups except for the time between the last dose and surgery (p < 0.01). There were 42 patients in the ulcerative colitis cohort; 48% had an undetectable vedolizumab level and 52% had a detectable vedolizumab level. There were no differences in any postoperative morbidity between ulcerative colitis groups. The Crohn's cohort had 27 patients; 48% had an undetectable vedolizumab levels and 52% had a detectable vedolizumab level. There was a significantly lower incidence of postoperative ileus in patients who had Crohn's disease with detectable vedolizumab levels compared with patients with an undetectable vedolizumab level (p < 0.04).

LIMITATIONS

Limitations include a low overall patient population and a high rate of stoma formation.

CONCLUSIONS

Serum vedolizumab levels do not influence postoperative morbidity in IBD. Vedolizumab may reduce the incidence of postoperative ileus in patients with Crohn's disease. See Video Abstract at http://links.lww.com/DCR/B574.

LOS NIVELES DE VEDOLIZUMAB EN SUERO PREOPERATORIO, NO AFECTAN LOS RESULTADOS POSTOPERATORIOS EN LA ENFERMEDAD INFLAMATORIA INTESTINAL

ANTECEDENTES:Se ha propuesto que el vedolizumab presenta menos complicaciones postoperatorias debido a su especificidad intestinal. Sin embargo, estudios sugieren un mayor riesgo de infecciones en el sitio quirúrgico, aunque los datos son contradictorios.OBJETIVO:Evaluar el efecto en los niveles del fármaco vedolizumab, en resultados postoperatorios de pacientes sometidos a cirugía mayor abdominal, por enfermedad inflamatoria intestinal.DISEÑO:Estudio retrospectivo de una base de datos mantenida prospectivamente.ENTORNO CLÍNICO:Pacientes intervenidos por un solo cirujano en un centro médico académico.PACIENTES:Un total de 72 pacientes con enfermedad inflamatoria intestinal sometidos a cirugía mayor abdominal.INTERVENCIONES:Exposición preoperatoria a vedolizumab.PRINCIPALES MEDIDAS DE VALORACIÓN:Morbilidad postoperatoria en pacientes con enfermedad inflamatoria intestinal, con niveles detectables versus no detectables de vedolizumab.RESULTADOS:Se incluyó en el estudio a un total de 72 pacientes. Treinta y ocho pacientes tuvieron niveles detectables de vedolizumab (> 1,6 mcg / ml) y 34 con niveles no detectables de vedolizumab. La tasa global de complicaciones fue del 39% y el íleo fue la complicación más común. No hubo diferencias significativas en las variables clínicas entre los grupos de pacientes con niveles detectables y no detectables de vedolizumab, excepto por el intervalo de tiempo entre la última dosis y la cirugía (p <.01). La cohorte de colitis ulcerosa tuvo 42 pacientes, el 48% con un nivel no detectable de vedolizumab y el 52% un nivel detectable de vedolizumab. No hubo diferencias en ninguna morbilidad postoperatoria entre los grupos de colitis ulcerosa. La cohorte de Crohn tuvo 27 pacientes, 48% con niveles no detectables de vedolizumab y el 52% con niveles detectables de vedolizumab. Hubo una incidencia significativamente menor de íleo postoperatorio en pacientes de Crohn con niveles detectables de vedolizumab, comparados con los pacientes con un nivel no detectable de vedolizumab (p <0,04).LIMITACIONES:Las limitaciones incluyen una baja población general de pacientes y una alta tasa de formación de estomas.CONCLUSIONES:Los niveles séricos de vedolizumab no influyen en la morbilidad postoperatoria de la enfermedad inflamatoria intestinal. Vedolizumab puede reducir la incidencia de íleo postoperatorio en pacientes de Crohn. Consulte Video Resumen en http://links.lww.com/DCR/B574.

Benefit of measuring vedolizumab concentrations in inflammatory bowel disease patients in a real-world setting

OBJECTIVES

We set out to determine the reasons for serum vedolizumab (VDZ) trough concentration (TC) measurements in inflammatory bowel disease (IBD) patients and to evaluate treatment modifications after therapeutic drug measurement (TDM). We also evaluated the effect of increased dosing on patients' response to VDZ therapy.

METHODS

We performed a retrospective cohort study of IBD patients who received VDZ therapy at Helsinki University Hospital and whose VDZ levels were measured between June 2014 and December 2018.

RESULTS

Altogether, 90 patients (32 Crohn's disease and 58 ulcerative colitis) and 141 VDZ TC measurements were included. 24.1% of measurements took place during induction and 75.9% during the maintenance phase. During induction, 64.7% reached the target TC >20µg/ml. During maintenance therapy, 82.2% of VDZ TCs were within or exceeded the suggested target range of 5-15µg/ml. Reasons for TDM were: secondary nonresponse (44.0%), assessment of adequate VDZ TC (25.5%), primary nonresponse (12.8%), adverse events (6.4%), and other (11.3%). No treatment changes occurred after 60.3% of VDZ measurements. Increased dose frequency was used after 25.5% of VDZ measurements and 33.3% of these patients experienced improvement. Altogether, 31 (34.4%) patients discontinued the therapy due to inadequate treatment response. No anti-vedolizumab antibodies were detected.

CONCLUSIONS

During the maintenance of VDZ therapy, the majority of VDZ TCs were within the suggested range. Measurement of VDZ TC did not lead to any treatment changes in two-thirds of patients. Dose optimization occurred in a quarter of patients and a third of them benefited from it.

Comparison of short- and long-term effectiveness between ustekinumab and vedolizumab in patients with Crohn's disease refractory to anti-tumour necrosis factor therapy

BACKGROUND

The best option between vedolizumab and ustekinumab after anti-tumour necrosis factor (TNF) failure remains unclear in Crohn's disease.

AIMS

To compare the short- and long-term effectiveness of vedolizumab and ustekinumab in Crohn's disease patients with prior anti-TNF exposure.

METHODS

All Crohn's disease patients treated with ustekinumab or vedolizumab after exposure to at least one anti-TNF agent were included from two referral centres. Primary endpoint was corticosteroid-free clinical remission defined as Crohn's disease activity index <150 at week 54. Deep remission (corticosteroid-free clinical remission and faecal calprotectin <100 µg/g) was assessed at week 14. Propensity-matched analyses were applied to make the two groups comparable.

RESULTS

Overall, 312 patients (ustekinumab = 224 and vedolizumab = 88) were included. After propensity score analysis, ustekinumab was more effective to achieve corticosteroid-free clinical remission at week 54 (49.3% vs 41.2%, P = 0.04) and deep remission at Week 14 (25.9% vs 3.8%, P = 0.02) than vedolizumab. The rate of primary nonresponders (6.7% vs 14.8%, P = 0.034) and the long-term risk of drug discontinuation due to therapeutic failure (HR = 1.53 [1.04-2.07], P = 0.029) were lower in patients treated with ustekinumab compared with vedolizumab. Predictors of ustekinumab failure were complicated phenotype (odds ratio [OR] = 2.35 [1.31-4.22]; P = 0.004) and anti-TNF primary non-response (OR = 2.55 [1.27-5.12]; P = 0.008). We did not find any predictor of corticosteroid-free clinical remission in patients treated with vedolizumab. Vedolizumab was less effective than ustekinumab in patients >35 years old (OR = 0.41 [0.19-0.87]), with noncomplicated phenotype (OR=0.42 [0.18-0.96]), no prior bowel resection (OR = 0.49 [0.24-0.96]), and no steroids at baseline (OR=0.47 [0.23-0.97]).

CONCLUSION

Ustekinumab was more effective to achieve early and long-term effectiveness than vedolizumab in Crohn's disease patients who previously failed response to anti-TNF agents.

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.

Personalized Medicine of Monoclonal Antibodies in Inflammatory Bowel Disease: Pharmacogenetics, Therapeutic Drug Monitoring, and Beyond

The pharmacotherapy of inflammatory bowel diseases (Crohn’s disease and ulcerative colitis) has experienced significant progress with the advent of monoclonal antibodies (mABs). As therapeutic proteins, mABs display peculiar pharmacokinetic characteristics that differentiate them from chemical drugs, such as aminosalicylates, antimetabolites (i.e., azathioprine, 6-mercaptopurine, and methotrexate), and immunosuppressants (corticosteroids and cyclosporine). However, clinical trials have demonstrated that biologic agents may suffer from a pharmacokinetic variability that could influence the desired clinical outcome, beyond primary resistance phenomena. Therefore, therapeutic drug monitoring (TDM) protocols have been elaborated and applied to adaptation drug doses according to the desired plasma concentrations of mABs. This activity is aimed at maximizing the beneficial effects of mABs while sparing patients from toxicities. However, some aspects of TDM are still under discussion, including time-changing therapeutic ranges, proactive and reactive approaches, the performance and availability of instrumental platforms, the widely varying individual characteristics of patients, the severity of the disease, and the coadministration of immunomodulatory drugs. Facing these issues, personalized medicine in IBD may benefit from a combined approach, made by TDM protocols and pharmacogenetic analyses in a timeline that necessarily considers the frailty of patients, the chronic administration of drugs, and the possible worsening of the disease. Therefore, the present review presents and discusses the activities of TDM protocols using mABs in light of the most recent results, with special attention on the integration of other actions aimed at exploiting the most effective and safe therapeutic effects of drugs prescribed in IBD patients.

Vedolizumab in Inflammatory Bowel Disease: West versus East

Background

Vedolizumab is a humanized immunoglobulin G1 monoclonal antibody, which binds to α4β7 integrin on T lymphocytes, thus disturbing the interaction with mucosal vascular addressin cell adhesion molecule 1 on the intestinal endothelial cells to interfere with lymphocyte trafficking to the gut.

Summary

Vedolizumab is a safe and effective drug to induce and maintain clinical remission in patients with Crohn's disease (CD) and ulcerative colitis (UC) in both clinical trials and real-world data. Various guidelines recommend vedolizumab as a first- or second-line treatment regimen for steroid-dependent, steroid, or immunomodulator refractory cases of UC and CD; however, it is more effective in anti-TNF-naive patients. The first head-to-head trial (VARSITY trial) comparing the efficacy of vedolizumab to adalimumab has shown better clinical remission and mucosal healing with vedolizumab.

Key Messages

In this review, we have discussed guidelines recommendation of vedolizumab use, as well as its safety data, use in special population, in presence of extraintestinal complications, therapeutic drug monitoring, data from Asian patients, along with other evolving concepts. Because of its excellent safety data and low immunogenicity, vedolizumab is an impressive option for patients with prior malignancy and less chance of reactivation of tuberculosis; however, cost remains an issue.

Association Between Vedolizumab Levels, Anti-vedolizumab Antibodies, and Endoscopic Healing Index in a Large Population of Patients with Inflammatory Bowel Diseases

BACKGROUND

The aim of this study was to assess the relationship between serum vedolizumab (VDZ) concentrations and antibodies to VDZ (ATV) in a large cohort of patients with inflammatory bowel diseases. Furthermore, we evaluated the association between serum VDZ concentrations and a novel serum-based biomarker panel designated as the endoscopic healing index (EHI), developed and validated for identifying mucosal inflammation in patients with Crohn's disease (CD).

METHODS

Retrospective study where results from patient samples submitted to a commercial clinical laboratory were included. Serum VDZ and ATV levels were analyzed using a drug-tolerant assay. In CD patients for whom both VDZ and EHI were available, VDZ concentrations were correlated with EHI. serum VDZ threshold analysis was performed using ROC curves, and the serum VDZ concentrations that best differentiated EHI < 20 (previously associated with endoscopic remission) were chosen.

RESULTS

A total of 9356 patients were included in the VDZ/ATV analysis. Detectable ATV was observed in 2.9% patients with significantly lower serum VDZ concentrations when compared to those with undetectable ATV [3.9 µg/mL (0-9.0) vs. 11.3 µg/mL (5.9-20.6), p < 0.0001]. Of the patients with serum VDZ result, 287 patients had a concomitant EHI test. An inverse correlation was observed between VDZ concentration and EHI (rho = - 0.20, p < 0.001). A serum VDZ concentration ≥ 15.7 µg/ml was best correlated wi th an EHI < 20 [AUROC: 0.67 (95% CI 0.57-0.77)].

CONCLUSIONS

Incidence of ATVs was low, but significantly associated with lower VDZ levels. A serum VDZ concentration threshold of ≥ 15.7 µg/ml was associated with endoscopic remission as defined by an EHI < 20.

Biologic Therapy for Ulcerative Colitis

Five biologics are approved for the treatment of ulcerative colitis (UC): infliximab, adalimumab, golimumab, vedolizumab, and ustekinumab. These drugs have varying levels of efficacy and are recommended as first-line treatment of moderate to severe UC. There has been only 1 head-to-head trial comparing the efficacy of the biologics, adalimumab and vedolizumab, which has important implications for management. Therapeutic drug monitoring of biologics, especially anti-TNF alpha agents, may improve the long-term efficacy of these agents. The future of treatment may include personalization of medications, based on patient-specific and disease-specific characteristics as well as biomarkers, along with appropriate therapeutic drug monitoring.

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.

Vedolizumab Serum Trough Concentrations and Response to Dose Escalation in Inflammatory Bowel Disease

Serum vedolizumab concentrations are associated with clinical response although, it is unknown if vedolizumab concentrations predict response to dose escalation. The aim of this study was to identify if vedolizumab trough concentrations predicted the response to vedolizumab dose escalation. We assessed a retrospective cohort of patients on maintenance vedolizumab dosing at five tertiary care centers with vedolizumab trough concentrations. Multivariate logistic regression was used to control for potential confounders of association of vedolizumab concentration and clinical status. Those who underwent a dose escalation were further examined to assess if vedolizumab trough concentration predicted the subsequent response. One hundred ninety-two patients were included. On multivariate analysis, vedolizumab trough concentration (p = 0.03) and the use of immunomodulator (p = 0.006) were associated with clinical remission. Receiver operator curve analysis identified a cut off of 7.4 μg/mL for clinical remission. Of the fifty-eight patients with dose escalated, 74% of those with a vedolizumab concentration <7.4 μg/mL responded versus 52% of those with a vedolizumab trough concentration ≥7.4 μg/mL (p = 0.08). After adjustment for relevant confounders, the odds ratio for response with vedolizumab concentration <7.4 μg/mL was 3.7 (95% CI, 1.1-13; p = 0.04). Vedolizumab trough concentration are associated with clinical status and can identify individuals likely to respond to dose escalation. However, a substantial portion of patients above the identified cut off still had a positive response. Vedolizumab trough concentration is a potentially helpful factor in determining the need for dose escalation in patients losing response.

Dissecting Common and Unique Effects of Anti-α4β7 and Anti-Tumor Necrosis Factor Treatment in Ulcerative Colitis

BACKGROUND AND AIMS

Vedolizumab is an anti-α4β7 antibody approved for the treatment of ulcerative colitis [UC]. Although it is assumed that vedolizumab blocks intestinal homing of lymphocytes, its effects on different intestinal cell populations are not fully stablished. In order to establish the unique mechanisms of action of vedolizumab in UC patients, we compared its effects to those induced by anti-tumour necrosis factor [TNF].

METHODS

Patients with active UC [endoscopic Mayo score >1] starting vedolizumab [n = 33] or anti-TNF [n = 45] and controls [n = 22] were included. Colon biopsies [at weeks 0, 14 and 46] and blood samples [at weeks 0, 2, 6, 14, 30 and 46] were used for cell phenotyping, transcriptional analysis [qPCR], and to measure receptor occupancy.

RESULTS

Vedolizumab, in contrast to anti-TNF, significantly reduced the proportion of α4β7+ cells within intestinal T subsets while preserving the percentage of α4β7+ plasma cells. The marked decrease in α4β7 did not change the percentage of colonic αEβ7+ cells [at 46 weeks]. Both vedolizumab and anti-TNF significantly downregulated inflammation-related genes in the colon of responders [Mayo score < 2]. Moreover, both treatments significantly decreased the percentage of intestinal, but not blood, total lymphocytes [T and plasma cells], as well as the proportion of α4β1+ cells within intestinal T lymphocytes.

CONCLUSIONS

Our data show that while vedolizumab and anti-TNF block two unrelated targets, they induce remarkably similar effects. On the other hand, vedolizumab's unique mechanism of action relies on blocking intestinal trafficking of α4β7 T cells, despite effectively binding to B and plasma cells that express α4β7.

Positioning Biologic Therapies in the Management of Pediatric Inflammatory Bowel Disease

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

Therapeutic drug monitoring in patients on biologics: lessons from gastroenterology

PURPOSE OF REVIEW

To give an overview on the role of therapeutic drug monitoring (TDM) of biologics in patients with inflammatory bowel disease (IBD).

RECENT FINDINGS

Numerous prospective exposure-response relationship studies and post-hoc analyses of randomized controlled trials (RCTs) show a positive correlation between biologic drug concentrations and favorable clinical outcomes in IBD. These studies also demonstrate that higher drug concentrations appear to be needed to achieve more stringent objective therapeutic outcomes. Reactive TDM rationalizes the management of primary nonresponse and secondary loss of response to antitumor necrosis factor (anti-TNF) therapy and is more cost-effective when compared with empiric dose optimization. Furthermore, recent data suggest that proactive TDM, with the goal of targeting a threshold drug concentration, is associated with better therapeutic outcomes when compared with empiric dose escalation and/or reactive TDM of infliximab or adalimumab. Finally, proactive TDM can also efficiently guide infliximab de-escalation or discontinuation in patients with IBD in remission.

SUMMARY

Reactive TDM is currently considered as standard of care, whereas proactive TDM is emerging as a new therapeutic strategy for better optimizing anti-TNF therapy in IBD. However, more data from prospective studies are needed before a wide implementation of TDM-based algorithms in real life clinical practice for newer biologics.

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.

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.

How, When, and for Whom Should We Perform Therapeutic Drug Monitoring?

The implementation of therapeutic drug monitoring (TDM) in the inflammatory bowel disease practice has evolved over the years. In the early days, the focus was merely on measuring and reporting drug concentrations. Later, these concentrations were considered in light of target concentrations that are related to clinical response. This not only allowed passively predicting a patient's future response, but it also triggered physicians and pharmacists to actively use the information to optimize the drug dosage to induce and maintain a clinical response in the future. Although reactive TDM, testing at time of loss of response, is widely accepted in practice, especially for anti-tumor necrosis factor antibodies, there are less data for the other monoclonal antibodies belonging to other classes. Besides reactive testing, there is a movement toward proactively adjusting biologic dosing to prevent loss of response, in keeping with the tight control philosophy of inflammatory bowel disease care. This review highlights the various assays available to measure drug concentrations and antidrug antibodies, as well as algorithmic approaches to TDM, the unmet needs and required studies to enable pharmacokinetics principles to be applied in the future.

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.

Influence of Drug Exposure on Vedolizumab-Induced Endoscopic Remission in Anti-Tumour Necrosis Factor [TNF] Naïve and Anti-TNF Exposed IBD Patients

BACKGROUND AND OBJECTIVES

Vedolizumab has demonstrated efficacy and safety in patients with Crohn's disease [CD] and ulcerative colitis [UC]. Endoscopic outcome data are limited, especially in anti-tumour necrosis factor [TNF] naïve patients. The present study compared endoscopic outcome in anti-TNF naïve and exposed patients, and explored if this was affected by drug exposure.

METHODS

We retrospectively analysed all patients initiating vedolizumab at our tertiary referral centre since 2015. For UC, endoscopic improvement was defined as a Mayo endoscopic subscore ≤1 at week 14. For CD, endoscopic remission was defined as absence of ulcerations at week 22. Vedolizumab trough concentrations were measured at week 6, week 14 and during maintenance.

RESULTS

A total of 336 patients were identified [53.3% CD], 20% of them being anti-TNF naïve. Endoscopic improvement was achieved by 56.1% of UC patients and endoscopic remission by 39.1% of CD patients. Endoscopic outcomes were significantly better in anti-TNF naïve vs exposed patients [all: 67.2% vs 42.0%, p = 0.0002; UC: 74.4% vs 50.0%, p = 0.02; CD: 57.1% vs 35.8%, p = 0.03]. Achievement of endoscopic end points significantly impacted long-term treatment continuation [p = 9.7 × 10-13]. A better endoscopic outcome was associated with significantly higher drug exposure in both CD and UC.

CONCLUSIONS

The results of this observational, single-centre real-life study suggest that vedolizumab may induce endoscopic remission in both CD and UC. Although anti-TNF naïve patients had a significantly better outcome, 42% of anti-TNF exposed patients still benefited endoscopically. A clear exposure-endoscopic response relationship exists, but not all patients will benefit from treatment intensification. Hence, predictive biomarkers remain necessary.

PODCAST

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Vedolizumab in the treatment of inflammatory bowel disease: evolving paradigms

Inflammatory bowel diseases, comprising Crohn's disease (CD) and ulcerative colitis (UC), are chronic, relapsing and remitting immune-mediated inflammatory diseases affecting the gastrointestinal tract. Vedolizumab is the first licensed drug in a group of 'gut-selective' biological agents used to treat inflammatory bowel diseases. The GEMINI registrational trials established the efficacy of vedolizumab for the induction and maintenance of remission in both CD and UC, with the most favourable results in tumour necrosis factor (TNF)-antagonist-naive patients. In recent years, a wealth of 'real-world' data has emerged supporting positive clinical, endoscopic and histological outcomes in patients treated with vedolizumab (VDZ) as well as reassuring safety data. More recently, the results of the first head-to-head trials of VDZ and TNF antagonists have been reported, as well as the results of a number of studies exploring the role of therapeutic drug monitoring with VDZ. This review brings together data reported on VDZ to date, including from the GEMINI trials, real-world data and emerging studies regarding therapeutic drug monitoring and immunogenicity. The safety profile of VDZ is also reviewed. Evolving treatment paradigms are explored, including data regarding the role of VDZ in perianal CD, post-operative complications and recurrence, extraintestinal manifestations and pregnancy.