Antihistamines in Eosinophilic Esophagitis

Study Overview
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Brief Summary
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Researchers are assessing the safety and effectiveness of antihistamines in the treatment of eosinophilic esophagitis.

Detailed Description
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The purpose of this research is to determine if antihistamines are safe and effective for the treatment of eosinophilic esophagitis. Antihistamines are frequently used for the treatment of gastroesophageal reflux disease and allergic disorders, and we hypothesize they will be effective in the treatment of eosinophilic esophagitis as well. The two antihistamines used in this study are loratadine and famotidine.

Official Title
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A Phase II, Randomized, Placebo-controlled Study Evaluating the Efficacy of Antihistamines in the Treatment of Eosinophilic Esophagitis (the ATEE Study)

Conditions
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Eosinophilic Esophagitis

Intervention / Treatment
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* Drug: Famotidine
* Drug: Loratadine
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients over the age of 18, male and female. Patients who carry the diagnosis of Eosinophilic Esophagitis (EoE) based on esophageal biopsies obtained within 6 months prior to enrollment (>15 eosinophils per hpf on at least 2 esophageal levels) Subjects must be able to give appropriate informed consent Exclusion Criteria: Not willing or able to sign consent. Patients who have used topical or systemic corticosteroid therapy for any reason in the previous 6 weeks. Patients who have been treated with acid-suppressing medications (PPI or H2 receptor antagonists) in the previous 6 weeks. Patients on immunosuppressive or immunomodulating medications in the previous 6 weeks. Patients with known allergies or hypersensitivity to anti-histamines. Patients who have contraindications to the procurement of esophageal biopsies including patients who have known bleeding disorders, a history of bleeding diathesis, or who are currently using warfarin or clopidogrel. Patients who have a contraindication to the performance of an esophagogastroduodenoscopy (EGD) including previous cardiopulmonary arrest during an endoscopic procedure. Patients who are pregnant.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Treatment Group<br>Participants receive Famotidine 40 mg tab twice daily by mouth and Loratadine 10 mg tab once daily by mouth for 12 weeks. | Drug: Famotidine<br>* 40 mg tab twice daily by mouth for 12 week duration<br>Drug: Loratadine<br>* 10 mg tab once daily by mouth for 12 week duration<br>|
| Placebo Comparator: Placebo Group<br>Participants receive Famotidine placebo tablet matching Famotidine orally twice daily for 12 weeks, and Loratadine placebo tablet matching Loratadine orally daily for 12 weeks. | Drug: Placebo<br>* Contains no active ingredient<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Adverse Events | Number of adverse events reported | 12 weeks | 
| Change in Maximum Eosinophil Count | Calculated by maximum eosinophils per esophagogastroduodenoscopy (EGD) high-power field (eos/hpf) after therapy with antihistamines. As measured by the percentage of change in maximum eosinophil count from baseline to 12 weeks. | 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Symptoms of Eosinophilic Esophagitis, as Measured by Dysphagia Symptom Questionnaire | Measured by the self-reported Dysphagia Symptom Questionnaire (DSQ). The DSQ ranges from 0 to 10, with a lower score indicating less symptoms and a higher score indicating more symptoms. | 12 weeks | 
| Change in Endoscopic Response, as Measured by the Endoscopic Reference Score | Percentage of subjects with endoscopic response as measured by the Eosinophilic Esophagitis (EoE) Endoscopic Reference Score (EREFS). The score ranges from 0 to 10, with a higher score indicating worse endoscopic findings of eosinophilic esophagitis. | 12 weeks | 
| Change in Histologic Response | Percentage of subjects with histologic response of ≤15 eos/hpf on biopsy at the lower and mid esophagus | 12 weeks |