640 - Factors Associated with Discontinuation of Oral Immunotherapy Treatment for Food Allergies in Clinical Practice

Publication Number: 640.4760

Eirene Fithian, Weill Cornell Medicine, New York, NY, United States; Allison Anderson, Latitude Food Allergy Care, Seattle, WA, United States; Samuel Shrank, Latitude Food Allergy Care, Boulder, CO, United States; Zahida Rani Maskatia, Latitude Food Allergy Care, Redwood City, CA, United States; Charlene Thomas, Weill Cornell Medicine, New York, NY, United States; Priya Katari, Weill Cornell Medicine, New York, NY, United States; Perdita Permaul, NY-Presbyterian/Weill Cornell Medicine, New York, NY, United States

Background: Fear of adverse reactions remains a key barrier to the uptake of oral immunotherapy (OIT) to treat food allergies. Characterizing reactions in those who discontinued OIT is essential to understanding risk factors and optimizing treatment safety.

Objective: To assess the incidence and severity of adverse reactions in those who discontinued OIT in clinical practice.

Design/Methods: A retrospective cohort study was conducted using clinical data collected from 1003 patients (ages 0-47yo) undergoing OIT at Latitude Food Allergy Care from 2018-2024. All administered OIT doses were reviewed to identify OIT reactions. Reactions were assessed by frequency, specific allergen, and graded as mild, moderate, or severe. Statistical analysis assessed the association between OIT status and OIT-related reactions for patients on peanut, tree nut, milk, egg, and sesame OIT.

Results: Among patients who began OIT, 5% discontinued treatment, with the frequency of discontinuation differing by allergen: milk (8%), sesame (7%), egg (6%), peanut (5%), and tree nut (5%). A regression model, adjusted for gender, age, and comorbidities, revealed that patients undergoing OIT for milk had 2.68 times higher odds of discontinuing OIT (p < 0.05). Milk (76%, 95% CI: 67%-84%) and egg (75%, 95% CI: 68%-82%) were also associated with a significantly higher incidence of any reaction compared to the mean (63%, 95% CI: 60%-66%).

Patients who discontinued OIT had similar frequencies of experiencing any reaction (58%, 95% CI: 45%, 73%) compared to those who reached maintenance (56%, 95% CI 52%, 61%). However, they showed a higher incidence of moderate reactions (23%, 95% CI: 11%, 35%) and severe reactions (14%, 95% CI: 5%, 23%) compared to those who reached maintenance (moderate: 18%, 95% CI:14%, 21%; severe: 7%, 95% CI: 5%, 10%). Additionally, patients who discontinued OIT had a higher incidence of gastrointestinal symptoms per dose, such as emesis and diarrhea (3.6% vs. 0.3%) and mild abdominal pain (0.5% vs. 0.1%).

Conclusion(s): While the overall percentage of OIT discontinuation was low across all allergens, discontinuation was associated with a higher incidence of moderate and severe reactions as well as increased frequency of reactions by dose. The higher reaction rates observed in milk and egg OIT emphasize the need for targeted strategies to better manage OIT for these specific allergens and further research to understand the underlying factors contributing to these reactions.