EoE Food Desensitization

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.

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.