Current options and investigational drugs for the treatment of eosinophilic esophagitis

Effectiveness of treatment with budesonide orodispersible tablets in 76 patients with eosinophilic oesophagitis - real-life experience from the population-based DanEoE cohort

BACKGROUND

Eosinophilic oesophagitis (EoE) is a chronic immune-mediated disease. In Denmark, the budesonide orodispersible tablet (BOT) is recommended as a second-line treatment for proton pump inhibitor-refractory EoE patients.

AIMS

To evaluate the effectiveness of treatment with BOT in adult EoE patients in a population-based setting in Denmark.

METHODS

This was a retrospective, registry-based, DanEoE cohort study of all 76 adult EoE patients treated with BOT and diagnosed between 2007 and 2021 in the North Denmark Region. After medical record revision, the EoE diagnosis was defined according to the AGREE consensus. Symptomatic response was based on the information found in the patients' medical reports and histologic remission was defined as <15 eosinophils per high-power field (eos/hpf).

RESULTS

Histologic remission was achieved in 89% of the patients treated with BOT who underwent histologic evaluation. Clinicohistologic remission was achieved in 71% of the patients who underwent both symptomatic and histologic evaluation. Despite histologic remission, 18% of patients still experienced symptoms. Non-responders were found in 7% of the patients. Complications were rare, with dilation of strictures performed in 7% and food bolus obstruction (FBO) occurring in 3%. Discontinuation of the treatment due to unacceptable side effects was observed in 11% of the treated patients.

CONCLUSIONS

Treatment with BOT effectively induced histologic remission in most of the EoE patients. Despite achieving histologic remission, approximately 1/5 of the patients were still symptomatic. Complications were rare. In non-responders and those with unacceptable side effects, alternative treatment options such as biologic agents might be needed.

Genomic insights into pediatric intestinal inflammatory and eosinophilic disorders using single-cell RNA-sequencing

Introduction

Chronic inflammation of the gastrointestinal tissues underlies gastrointestinal inflammatory disorders, leading to tissue damage and a constellation of painful and debilitating symptoms. These disorders include inflammatory bowel diseases (Crohn's disease and ulcerative colitis), and eosinophilic disorders (eosinophilic esophagitis and eosinophilic duodenitis). Gastrointestinal inflammatory disorders can often present with overlapping symptoms necessitating the use of invasive procedures to give an accurate diagnosis.

Methods

This study used peripheral blood mononuclear cells from individuals with Crohn's disease, ulcerative colitis, eosinophilic esophagitis, and eosinophilic duodenitis to better understand the alterations to the transcriptome of individuals with these diseases and identify potential markers of active inflammation within the peripheral blood of patients that may be useful in diagnosis. Single-cell RNA-sequencing was performed on peripheral blood mononuclear cells isolated from the blood samples of pediatric patients diagnosed with gastrointestinal disorders, including Crohn's disease, ulcerative colitis, eosinophilic esophagitis, eosinophilic duodenitis, and controls with histologically healthy gastrointestinal tracts.

Results

We identified 730 (FDR < 0.05) differentially expressed genes between individuals with gastrointestinal disorders and controls across eight immune cell types.

Discussion

There were common patterns among GI disorders, such as the widespread upregulation of MTRNR2L8 across cell types, and many differentially expressed genes showed distinct patterns of dysregulation among the different gastrointestinal diseases compared to controls, including upregulation of XIST across cell types among individuals with ulcerative colitis and upregulation of Th2-associated genes in eosinophilic disorders. These findings indicate both overlapping and distinct alterations to the transcriptome of individuals with gastrointestinal disorders compared to controls, which provide insight as to which genes may be useful as markers for disease in the peripheral blood of patients.

Proton pump inhibitor effect on esophageal protein signature of eosinophilic esophagitis, prediction, and evaluation of treatment response

BACKGROUND

Recently, we have identified a dysregulated protein signature in the esophageal epithelium of eosinophilic esophagitis (EoE) patients including proteins associated with inflammation and epithelial barrier function; however, the effect of proton pump inhibitor (PPI) treatment on this signature is unknown. Herein, we used a proteomic approach to investigate: (1) whether PPI treatment alters the esophageal epithelium protein profile observed in EoE patients and (2) whether the protein signature at baseline predicts PPI response.

METHODS

We evaluated the protein signature of esophageal biopsies using a cohort of adult EoE (n = 25) patients and healthy controls (C) (n = 10). In EoE patients, esophageal biopsies were taken before (pre) and after (post) an 8-week PPI treatment, determining the histologic response. Eosinophil count PostPPI was used to classify the patients: ≥15 eosinophils/hpf as non-responders (non-responder) and < 15 eosinophils/hpf as responders (R). Protein signature was determined and differentially accumulated proteins were characterized to identify altered biological processes and signaling pathways.

RESULTS

Comparative analysis of differentially accumulated proteins between groups revealed common signatures between three groups of patients with inflammation (responder-PrePPI, non-responder-PrePPI, and non-responder-PostPPI) and without inflammation (controls and responder-PostPPI). PPI therapy almost reversed the EoE specific esophageal protein signature, which is enriched in pathways associated with inflammation and epithelial barrier function, in responder-PostPPI. Furthermore, we identified a set of candidate proteins to differentiate responder-PrePPI and non-responder-PrePPI EoE patients before treatment.

CONCLUSION

These findings provide evidence that PPI therapy reverses the alterations in esophageal inflammatory and epithelial proteins characterizing EoE, thereby providing new insights into the mechanism of PPI clinical response. Interestingly, our results also suggest that PPI response could be predicted at baseline in EoE.

Determinant factors for first-line treatment choice and effectiveness in pediatric eosinophilic esophagitis: an analysis of the EUREOS EoE CONNECT registry

This study compared short-term effectiveness of proton pump inhibitors (PPI), swallowed topical corticosteroids (STC), and dietary therapies in reversing clinical and histological features in pediatric patients with eosinophilic esophagitits (EoE). Determinants for treatment choice and PPI therapy effectiveness were also assessed.  A cross-sectional study analysis of patients under 18 years old recruited onto the multicenter EoE CONNECT registry was performed. Clinico-histological response was defined as symptomatic improvement plus a peak eosinophil count below 15 per high-power field after treatment. Effectiveness of first-line options used in monotherapy was compared. Overall, 393 patients (64% adolescents) receiving PPI, STC, or dietary monotherapy to induce EoE remission were identified. PPI was the preferred option (71.5%), despite STC providing the highest clinico-histological response rates (66%) compared to PPI (44%) and diet (42%). Logistic regression identified fibrotic features and recruitment at Italian sites independently associated to first-line STC treatment; age under 12 associated to dietary therapy over other options. Analysis of 262 patients in whom PPI effectiveness was evaluated after median (IQR) 96 (70-145) days showed that this effectiveness was significantly associated with management at pediatric facilities and use of high PPI doses. Among PPI responders, decrease in rings and structures in endoscopy from baseline was documented, with EREFS fibrotic subscore for rings also decreasing among responders (0.27 ± 0.63 vs. 0.05 ± 0.22, p < 0.001).    Conclusion: Initial therapy choice for EoE depends on endoscopic phenotype, patient's age, and patients' origin. High PPI doses and treatment in pediatric facilities significantly determined effectiveness, and reversed fibrotic endoscopic features among responders. What is Known: • Proton pump inhibitors are widely used to induce and maintain remission in EoE in real practice, despite other first-line alternative therapies possibly providing higher effectiveness. What is New: • Proton pump inhibitors represent up to two-thirds of first-line monotherapies used to induce EoE remission in pediatric and adolescent patients with EoE. The choice of STC as first-line treatment for EoE was significantly associated with fibrotic features at baseline endoscopy and recruitment in Italian centers; age less than 12 years was associated with dietary therapy. • PPI effectiveness was found to be determined by use of high doses, attendance at pediatric facilities, presenting inflammatory instead of fibrotic or mixed phenotypes, and younger age. Among responders, PPI therapy reversed both inflammatory and fibrotic features of EoE after short-term treatment.

Swallowed topical corticosteroids for eosinophilic esophagitis: Utilization and real-world efficacy from the EoE CONNECT registry

BACKGROUND

Swallowed topical corticosteroids (tC) are common therapy for patients with eosinophilic esophagitis (EoE). Widely heterogeneous results have occurred due to their active ingredients, formulations and doses.

OBJECTIVE

To assess the effectiveness of topical corticosteroid therapy for EoE in real-world practice.

METHODS

Cross-sectional study analysis of the multicentre EoE CONNECT registry. Clinical remission was defined as a decrease of ≥50% in dysphagia symptom scores; histological remission was defined as a peak eosinophil count below 15 per high-power field. The effectiveness in achieving clinico-histological remission (CHR) was compared for the main tC formulations.

RESULTS

Overall, data on 1456 prescriptions of tC in monotherapy used in 866 individual patients were assessed. Of those, 904 prescriptions with data on formulation were employed for the induction of remission; 234 reduced a previously effective dose for maintenance. Fluticasone propionate formulations dominated the first-line treatment, while budesonide was more common in later therapies. A swallowed nasal drop suspension was the most common formulation of fluticasone propionate. Doses ≥0.8 mg/day provided a 65% CHR rate and were superior to lower doses. Oral viscous solution prepared by a pharmacist was the most common prescription of budesonide; 4 mg/day provided no benefit over 2 mg/day (CHR rated being 72% and 80%, respectively). A multivariate analysis revealed budesonide orodispersible tablets as the most effective therapy (OR 18.9, p < 0.001); use of higher doses (OR 4.3, p = 0.03) and lower symptom scores (OR 0.9, p = 0.01) were also determinants of effectiveness.

CONCLUSION

Reduced symptom severity, use of high doses, and use of budesonide orodispersible tablets particularly were all independent predictors of tC effectiveness.

Proton-Pump Inhibitors in Eosinophilic Esophagitis: A Review Focused on the Role of Pharmacogenetics

Proton-pump inhibitors (PPIs) are the most administered first-line treatment for eosinophilic esophagitis (EoE). However, only around half of EoE patients respond histologically to a double dosage of PPI. In addition, 70% of responders maintain EoE in remission after tapering the PPI dose. In order to avoid endoscopy with biopsies-the only accurate method of assessing PPI response-efforts have been made to identify PPI responder patients. The clinical or endoscopic features and biomarkers evaluated so far, however, have not proven to be sufficient in predicting PPI response. Although new approaches based on omics technologies have uncovered promising biomarkers, the specialized and complex procedures required are difficult to implement in clinical settings. Alternatively, PPI pharmacogenetics based on identifying variations in CYP2C19 and STAT6 genes have shown promising results in EoE, and could easily be performed in most laboratories. Other genetic variations have also been associated with PPI response and may explain those cases not related to CYP2C19 or STAT6. Here, we provide an overview of PPI treatment in EoE and evidence of how genetic variations in CYP2C19 and other genes could affect PPI effectiveness, and also discuss studies evaluating the role of pharmacogenetics in predicting PPI response in patients with EoE.

Fibrous Remodeling in Eosinophilic Esophagitis: Clinical Facts and Pathophysiological Uncertainties

Eosinophilic esophagitis (EoE) is a chronic, progressive, type 2 inflammatory disease with increasing global prevalence. An eosinophil-predominant inflammation that permeates the epithelium and deeper esophageal layers characterizes the disease. Several cytokines, mainly derived from inflammatory T-helper 2 (Th2) cells and epithelial cells, are involved in perpetuating inflammatory responses by increasing surface permeability and promoting tissue remodeling characterized by epithelial-mesenchymal transition (EMT) and collagen deposition. This leads to esophageal strictures and narrow caliber esophagi, which are proportional a patient's age and untreated disease length. Pathophysiological mechanisms leading to EoE have been described in recent years, and transforming growth factor beta (TGF)-beta have been involved in fibrotic phenomena in EoE. However, evidence on the dependence of these phenomena on TGF-beta is scarce and contradictory. This review provides state-of-the art knowledge on intimate mechanisms of esophageal fibrosis in EoE and its clinical consequences.

Reproducibility and Generalizability of the Web-Based Tool to Predict Lamina Propria Fibrosis in Eosinophilic Esophagitis

We investigated reproducibility and generalizability of the recently developed web-based model to predict lamina propria fibrosis (LPF) in esophageal biopsies with inadequate lamina propria (LP) from patients with eosinophilic esophagitis (EoE) using an independent dataset (N = 183). For grade and stage scores of LPF, the area under the curve for predictive model was 0.77 (0.69-0.84) and 0.75 (0.67-0.82), and its accuracy was 78% and 72%, respectively. These model performance metrics were similar to that of the original model. A significant positive correlation was noted between the models' predictive probability and the grade and stage of LPF assessed by a pathologist (grade: r2 = 0.48, P < 0.001; and stage: r2 = 0.39, P < 0.001). These results support the reproducibility and generalizability of the web-based model to predict the presence of LPF in esophageal biopsies with inadequate LP in EoE. Additional studies are warranted to refine the web-based predictive models to provide predictive probability for sub-scores of LPF severity.

New approaches to diet therapy for eosinophilic esophagitis

PURPOSE OF REVIEW

An empiric step-up (2-4-6) elimination diet remains the most common dietary approach in clinical practice when treating eosinophilic esophagitis (EoE). However, research in this field has fallen behind pharmacological therapy. This review aims to summarize novel approaches to dietary therapy for EoE.

RECENT FINDINGS

A first prospective multicenter study in 41 pediatric patients (mean age 9 years) has evaluated the efficacy of a cow's milk elimination diet. This dietary approach led to histological remission in 51% of patients, albeit a caveat is that up to 80% of patients were receiving concomitant therapy with proton pump inhibitors. In a series of 18 adult patients with documented milk-induced EoE, ingestión of 400 ml of sterilized milk (boiled for up to 20 min) daily for 8 weeks did not induce histologic relapse in two-thirds of patients.

SUMMARY

Milk elimination diet is effective in one-half of pediatric EoE patients and should likely be the first choice in children with EoE (within a step-up dietary approach). Promising data on tolerance of sterilized milk in adults with milk-induced EoE (66%) merit further replication in children, which may radically improve quality of life for patients and their caregivers.

Current treatment options and long-term outcomes in patients with eosinophilic esophagitis

INTRODUCTION

Dietary and pharmacological (proton pump inhibitors, swallowed topical corticosteroids) therapies are effective for induction of clinical and histological remission of eosinophilic esophagitis. However, data evaluating their long-term efficacy and safety is limited.

AREAS COVERED

Since eosinophilic esophagitis is chronic, clinical, endoscopic, and histological features usually recur when successful treatments are stopped. In untreated patients, persistent esophageal eosinophilic inflammation may progress to fibrostenosis over time, giving place to strictures and narrow-caliber esophagi. This article comprehensively reviews available data on long-term maintenance of eosinophilic esophagitis with pharmacological and dietary treatment. It also discusses limitations re: available literature and outlines data gaps on adherence to therapy and monitoring disease activity in the long-term.

EXPERT OPINION

Evidence indicates that long-term maintenance therapy may decrease the risk of esophageal stricture, food bolus impaction, and need for dilation in patients with eosinophilic esophagitis. Further knowledge on eosinophilic esophagitis phenotypes is needed to ascertain who will benefit best from sustained therapy. Unanswered questions include an adequate definition for sustained remission, best strategies for maintenance drugs and diets, enhancement of treatment adherence, and proper monitoring for long-term surveillance.

Drug treatment strategies for eosinophilic esophagitis in adults

INTRODUCTION

Eosinophilic esophagitis (EoE) is a clinical and pathological disorder, characterized by symptoms of esophageal dysfunction, and eosinophil-predominant inflammation restricted to the esophagus. Treatment outcomes include symptomatic remission, histological and endoscopic normalization and improving quality of life. Besides dietary modifications and endoscopic dilation, drugs available are swallowed topical corticosteroids (STCs) with reduced bioavailability and proton pump inhibitors (PPI).

AREAS COVERED

Herein, the authors review the current treatment strategies for EoE in adults, providing the reader with their expert perspectives. The authors give discussion to the value of PPIs as a first-line therapy for EoE, in addition to the use of STCs. The current development of new formulations of STCs targeting the esophagus and novel therapies aimed at blocking molecular pathways are also discussed. Finally, the authors briefly look at the value of monoclonal antibodies targeting IL-5RA, IL-13, IL-4 or Siglec8, and oral S1PR agonists to the treatment of EoE.

EXPERT OPINION

Viscose formulations of STC designed to coat the esophagus and new effervescent orodispersible tablets provide increased effectiveness at low doses. Investigational therapies that target several Th2-associated diseases seem useful in EoE. Comparative effectiveness and cost-utility analyses will help to position them in a complex therapeutic scenario.