Immunologic Basis of Food Protein-Induced Enterocolitis Syndrome

This is a phase I multicenter clinical trial that aims to find the optimal dose for conducting a novel low-dose, multi-day oral food challenge (OFC) protocol for diagnosing food protein-induced enterocolitis syndrome (FPIES). Individuals ages 1-60 years with a history of suspected or confirmed FPIES will be eligible for enrollment. Recruitment is expected to occur over 3 years.

At the time of enrollment, participants will undergo screening (Visit 0) and complete a baseline gastrointestinal symptom diary. At Visit 1 (Day 1), participants will undergo a supervised Low Dose OFC to their FPIES trigger. Those who react will be considered low-threshold reactors and recommended to continue strict avoidance of their FPIES trigger. For participants who do not react at the Day 1 Low Dose OFC, continued participation involves a daily home challenge on Days 2-7. Participants will be provided with a diary to monitor symptoms. If objective or persistent subjective symptoms develop, participants will be advised to contact the study team before consuming any further doses. Participants will return for Visit 2 on Day 8. Those who reported symptoms that led to discontinuation of the home challenge will undergo biospecimen collection. Those who tolerated the Day 1 supervised and Days 2-7 home challenges will undergo a High Dose OFC to their suspected FPIES trigger. Those who tolerate this challenge will be considered to have outgrown their FPIES and instructed to introduce the food regularly at home. Those who react will be considered high-threshold reactors and advised to continue strict avoidance of their FPIES trigger and continue routine allergy care.