New Developments in the Diagnosis and Treatment of Eosinophilic Esophagitis

Efficacy and Safety of Monoclonal Antibodies for the Treatment of Eosinophilic Esophagitis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND AND AIMS

Monoclonal antibodies (MAbs) have clinical benefits for treating several atopic diseases. However, consensus on its use for eosinophilic esophagitis (EoE) is lacking. The present meta-analysis aimed to compare the efficacy and safety of MAbs versus placebo for treating EoE.

METHODS

We searched PubMed, Embase, and Cochrane Library for randomized controlled trials (RCTs). The primary outcomes were changes in peak esophageal eosinophils count/high power field (HPF) and mean esophageal eosinophils count/HPF. The secondary outcomes were changes in the EoE-Histology Scoring System (EoE-HSS), Endoscopic Reference Score (EREFS), dysphagia score, and adverse events (AEs). We compared binary outcomes using risk ratio (RR) and continuous outcomes using mean difference (MD) or standardized mean difference (SMD), with 95% confidence interval (CI). Considering the diversity of mechanistic properties of MAbs, a pre-specified subgroup analysis by MAb mechanism of action was performed for all outcomes, provided that at least two studies were in each subgroup. Heterogeneity was assessed using Cochran's Q test and I2 statistics.

RESULTS

6 RCTs were included (533 patients). Compared to placebo, MAbs led to a significant reduction in peak esophageal eosinophils count/HPF (MD -0.78; CI 95% -0.87, -0.6801) and mean esophageal eosinophils count/HPF (SMD -0.79; CI 95% -1.5, -0.08). Moreover, MAbs significantly reduced EoE-HSS scores (grade score: SMD -9.31; 95% CI -13.95, -4.6701; stage score: SMD -10.18; 95% CI -15.06, -5.31), EREFS (SMD -5.95; CI 95% -9.19, -2.71) and dysphagia score (SMD -1.79; CI 95% -3.36, -0.23) without increasing AEs compared to placebo. Among those MAbs whose mechanism of action includes the blockage of the receptor for IL-13 (Dupilumab, QAX576, and RPC4046), the scores of EoE-HSS grade, EoE-HSS stage, EREFS, and dysphagia were significantly reduced, and they presented a similar risk of overall and serious AEs compared to placebo.

CONCLUSION

MAbs seem effective and safe in reducing esophageal eosinophil infiltrate, EoE-HSS score, EREFS score, and dysphagia symptoms in patients with EoE. However, further evidence is needed to establish its place in EoE management.

Current state of biologics in treating eosinophilic esophagitis

OBJECTIVE

Eosinophilic esophagitis (EoE) is a chronic, allergen-mediated, eosinophil-predominant, type 2 inflammatory disease that progresses to fibrostenosis of the esophagus if left untreated. This review focuses on biologics therapy in EoE.

DATA SOURCES

Manuscripts on EoE treatments are identified on PubMed.

STUDY SELECTIONS

Original research, randomized controlled trials, retrospective studies, meta-analyses, case series, and case reports of high relevance are selected and reviewed.

RESULTS

Biologics have been used as investigational therapies for EoE in clinical studies over the years, based on earlier work that identified key cytokines and mediators of eosinophilic inflammation and, more recently, type 2 inflammation that underlie EoE pathogenesis. Dupilumab, a monoclonal antibody that targets the interleukin (IL)-4Rα chain, thereby interfering with IL-4 and IL-13 binding with the receptor, was recently approved by the Food and Drug Administration for EoE. Dupilumab improved clinical symptoms, endoscopic scores, histologic inflammation, and esophageal distensibility. Several clinical trials that target key cytokines such as IL-5, IL-13, and thymic stromal lymphopoietin in EoE are still ongoing.

CONCLUSION

Topical corticosteroid, proton pump inhibitor therapy, elimination diet, and dilation are widely accepted treatment modalities for EoE. Dupilumab is the first Food and Drug Administration-approved therapy for EoE. Other studies evaluating biologics that target eosinophils, key cytokines, and inflammatory pathways in EoE are ongoing. Treatment algorithms are needed to position EoE therapies as they emerge.

Esophageal Eosinophilia Is Common Among Relatives of Eosinophilic Esophagitis Patients

BACKGROUND & AIMS

Familial clustering of eosinophilic esophagitis (EoE) has been described, and we report on the biopsy-assessed prevalence of esophageal eosinophilia (EE) in first-degree family members. The aim was to determine the prevalence of EE in first-degree adult relatives (FDRs) of EoE patients.

METHODS

Index EoE patients diagnosed by EE (>15 eosinophils per high-power field) and proton pump inhibitor nonresponsiveness were identified and family trees were constructed. Adult FDRs were invited to undergo upper endoscopy with esophageal biopsies and to complete reflux, dysphagia, and allergy/atopy questionnaires. Questionnaire information was gathered only for those who responded as per institutional review board purview. Records from other children and adult FDRs with prior EoE diagnoses also were obtained when permission was obtained. Simple and multivariable logistic regression models were used to evaluate the unadjusted and odds ratios of EoE for demographic and clinical variables.

RESULTS

A total of 239 FDRs from 37 index EoE patients were identified. Seventy-one of 239 adult (age, >18 y) FDRs completed endoscopy and questionnaires and 18 of 71 FDRs had EE. An additional 17 FDRs were confirmed to have EE after external medical record retrieval, resulting in a total of 35 of 239 (14.6%) FDRs with EE. Significantly more male FDRs had EE compared with female FDRs (P = .027). Proton pump inhibitors, dysphagia, gastroesophageal reflux disease, asthma, and reflux symptoms predicted EE in FDRs. FDRs who had EE reported hay fever, allergic eye symptoms, and food allergy more frequently than those without EE (P = .03, P = .001, and P = .02, respectively). Specifically, younger age, higher serum eosinophils, being male, and having food allergies all were associated with higher odds of EoE (P = .0211, P = .0031, P = .0362, and P = .0089, respectively).

CONCLUSIONS

The prevalence of esophageal eosinophilia is extremely high and male-predominant in first-degree relatives of EoE patients. Symptoms of hay fever, allergic eye symptoms, and food allergy were predictors of EE in FDRs. Dysphagia did not predict esophageal eosinophilia. Family members of EoE patients are at risk for EE, particularly those who have atopic symptoms.

Outcomes of eosinophilic esophagitis in patients managed in a multidisciplinary clinic

Background: Eosinophilic esophagitis is a complex disease with an increasing prevalence. Multidisciplinary teams are often needed to manage this difficult-to-treat condition. Objective: To observe the clinical and histologic outcomes of patients with eosinophilic esophagitis after management in a multidisciplinary clinic. Methods: An observational, retrospective chart review was conducted to include all patients referred to the Walter Reed National Military Medical Center multidisciplinary eosinophilic esophagitis clinic between August 2012 and February 2021. Only patients who had at least one esophagogastroduodenoscopy before referral, one or more visits and endoscopy after multidisciplinary management, and documented clinical symptoms were included. Statistical analysis was performed by using McNemar and Wilcoxon tests. Results: A total of 103 patients were included in the study, with a mean age at diagnosis of 17.9 years. Management in the multidisciplinary clinic was associated with a reduction in solid-food dysphagia by 70.9%, poor growth by 70.8%, and emesis or regurgitation by 87.5%. We observed that 48.5% and 62.1% had histologic remission (<15 eosinophils/hpf) on the initial and any post-multidisciplinary endoscopy, respectively. Only seven patients (5.8%) with two or more visits and endoscopies did not achieve histologic remission. More than two-thirds of the patients (68.9%) required combination therapy to achieve remission. Conclusion: Although an observational study, these findings may suggest that the management of patients with eosinophilic esophagitis in a multidisciplinary clinic may improve the likelihood of clinical and histologic remission. Targeted management with a multidisciplinary approach may reduce overall morbidity and slow disease progression; however, more research is needed.

Management of Eosinophilic Esophagitis During Oral Immunotherapy

Food allergies are antigen-driven diseases that can lead to IgE-mediated reactions of immediate hypersensitivity (eg, anaphylaxis triggered by a single food) or non-IgE reactions of delayed hypersensitivity such as eosinophilic esophagitis (eg, inability to eat multiple foods manifesting as abdominal pain, choking, dysphagia, vomiting, reflux, food impaction). Although both types of disease have their own unique set of challenges in diagnosis and management, it is a particularly vexing problem when a patient is afflicted by both conditions. This situation can happen when individuals with IgE-mediated food allergy undergo desensitization using currently available forms of oral immunotherapy. In this Grand Rounds Review, we review diagnostic approaches to oral immunotherapy-associated eosinophilic esophagitis, potential relationships between primary and secondary eosinophilic esophagitis, potential management approaches, areas of uncertainty, and upcoming research. Optimally supporting patients in their journey with food allergy requires shared decision making regarding alternative management strategies and the stimulation of robust research.

Long-term Efficacy and Tolerability of RPC4046 in an Open-Label Extension Trial of Patients With Eosinophilic Esophagitis

BACKGROUND & AIMS

The short-term efficacy of RPC4046, a monoclonal antibody against interleukin-13, has been shown in patients with eosinophilic esophagitis (EoE). We investigated the long-term efficacy and safety of RPC4046 in an open-label, long-term extension (LTE) study in adults with EoE.

METHODS

We analyzed data from 66 patients who completed the 16-week, double-blind, induction portion of a phase 2 study of RPC4046 (180 mg or 360 mg/wk) vs placebo and then completed a 52-week LTE, receiving open-label RPC4046 360 mg/wk. The study was conducted at 28 centers in 3 countries; patients were enrolled between September 2014 and January 2017. Outcomes were stratified by double-blind dose group and included esophageal eosinophil counts, EoE endoscopic reference score, EoE histologic scoring system score, symptom-based EoE activity index score, and safety.

RESULTS

By week 12 of the LTE, esophageal eosinophil mean and peak counts, total EoE endoscopic reference scores, and EoE histologic scoring system grade and stage scores did not differ considerably between patients who originally received placebo vs RPC4046. Most patients maintained responses through week 52. Symptom remission (symptom-based EoE activity index score, ≤20) increased from 14% at LTE entry to 67% at LTE week 52 in placebo‒RPC4046 patients and from 30% to 54% in RPC4046‒RPC4046 (either dose) patients. Of the 28 patients who did not have a histologic response to RPC4046 during the double-blind induction phase, 10 patients (36%) achieved response during the LTE. The most common adverse events were upper respiratory tract infection (21%) and nasopharyngitis (14%).

CONCLUSIONS

One year of treatment with RPC4046 is generally well tolerated and results in continued improvement and/or maintenance of endoscopic, histologic, and clinical measures of EoE disease activity relative to baseline.

TRIAL REGISTRATION

NCT02098473.

Allergies and Eosinophilic Esophagitis-Current Updates for the Pediatric Gastroenterologist

PURPOSE OF REVIEW

The purpose of this article is to review recent developments demonstrating the role of allergies, the utility of allergy testing, and the role of the allergist in eosinophilic esophagitis (EoE) management.

RECENT FINDINGS

The majority of patients with EoE have concurrent atopic disorders including food anaphylaxis, asthma, allergic rhinitis, and eczema. An atopic population likely is at greater risk for EoE. Delayed type hypersensitivity to food antigens is the most common pathogenic mechanism. Aeroallergens and pollen-food cross-reactivity also can trigger EoE. Th2 cell-mediated adaptive and innate immunity in response to epithelial damage occurs via IL-13- and IL-4-producing T cells and innate lymphoid cells. While IgE testing for foods is insufficient to build an elimination diet, IgE-mediated allergy may play a role in EoE severity and clinical course. There is strong evidence that Th2 immunity drives EoE. Optimal EoE management should include elucidating and managing EoE triggers and concurrent atopic diatheses.