EoE Food Desensitization

This is a single-center, prospective, pilot clinical trial in which children ages 3-17 years with eosinophilic esophagitis (EoE) who have a known food that triggers EoE flares receive oral desensitization with that specific food antigen, followed by reintroduction of that food into the diet. The purpose of this study is to investigate the safety and feasibility of oral desensitization in children with EoE so that, if determined to be safe, can be repeated on a larger scale to determine efficacy.

Eosinophilic esophagitis (EoE) is a clinicopathologic disorder of the esophagus triggered by food and/or environmental allergens and is characterized by symptoms of esophageal dysfunction and eosinophilia of the esophagus. Current therapy is centered on controlling inflammation with steroids and/or food antigen avoidance. Such treatment options have significant side effects and reduce quality of life, especially in children. The purpose of the study is to discover a way for flare-provoking foods to be reintroduced into the child's diet without the need for medical therapy.

The study would involve children ages 3-17 years with biopsy-proven EoE who have a known flare-inducing food trigger. Following baseline blood work and esophagogastroduodenoscopy (EGD), the investigators will initiate oral desensitization treatment in which the child swallows a spray solution containing his or her specific food allergen extract in increasing concentrations twice daily for 4 months. The next phase of the study would involve reintroduction of the actual food for 4 weeks followed by repeat blood work and EGD. Success would be defined by having a peak eosinophil count \<15 per high power field on the final esophageal biopsy.

Oral food desensitization has been well-studied in patients with food allergies but never in patients with pre-existing EoE. In those studies, the adverse events included mild reactions, such as watery eyes, rhinitis, sneezing, throat pruritus, transient erythema and abdominal pain. These reactions usually did not require stopping desensitization and were well controlled by antihistamines and steroids. Benefits include children having a less restricted diet and eliminating the need for steroid therapy. This study should yield valuable information regarding the management of EoE, thereby improving the current understanding of its pathogenesis.

Eligibility Criteria:
Inclusion Criteria:

1. Pediatric patient, ages 3-17 years, with known diagnosis of EoE based upon esophageal biopsy demonstrating ≥15 eos/hpf and lack of symptomatic or histological response to PPI therapy and/or normal esophageal pH evaluation.
2. Known or suspected flare-inducing food trigger based upon supporting histological evidence.
3. Already undergoing a baseline EGD followed by food reintroduction and repeat EGD, as standard of care at the recommendation of the child's gastroenterologist.
4. Signed informed consent for the subject's participation in the study provided by the parent/ legal guardian and child/adolescent assent for subjects 7-17 years.
5. Assent by the patient's pediatric gastroenterologist for the patient's participation in the study.

Exclusion Criteria:

1. Presence of other disorders associated with similar clinical, histological or endoscopic features, such as PPI-responsive esophageal eosinophilia, esophageal eosinophilia associated with gastroesophageal reflux disease (GERD), Crohn's disease, infectious esophagitis (i.e. herpes simplex virus or candida), drug-associated esophagitis, collagen vascular disease, hypereosinophilic syndrome and eosinophilic gastroenteritis.
2. Previous or current diagnosis of cancer or leukemia.
3. History of chemotherapy within the past 3 months.
4. History of esophageal stricture or food impaction.
5. History of anaphylaxis or other severe adverse reaction to the specific food trigger being tested.