05-05-2025
Severity of Reactions Linked to Stopping Oral Immunotherapy
Patients with food allergy who discontinued oral immunotherapy were those who were more likely to experience a reaction to the treatment than those who reached maintenance of allergen foods, according to research at the Pediatric Academic Societies 2025 Meeting.
They were also more likely to experience moderate and severe reactions, particularly mild abdominal pain, vomiting, diarrhea, and pruritus, reported Eirene Fithian, of the MD program at Weill Cornell Medical College in New York City, and colleagues in a poster.
'Oral immunotherapy discontinuation was low overall but varied by allergen, with higher discontinuation rates observed for allergens with a high incidence of severe reactions compared to the mean,' they reported.
Food allergy affects an estimated 8% of children and 10% of adults in the United States, but advances in oral immunotherapy have opened up treatment options for these individuals, the researchers noted.
'The fear of adverse reactions remains a barrier to treatment, yet little data exists on the role of adverse reactions in treatment discontinuation,' they wrote. 'Identifying factors associated with oral immunotherapy discontinuation is critical to addressing concerns and improving the safety and efficacy of oral immunotherapy.'
The researchers conducted a retrospective cohort study with data from 1003 patients, aged less than 1 year to 47 years, who underwent oral immunotherapy for peanut, tree nut, milk, egg, and/or sesame allergy at Latitude Food Allergy Care between 2018 and 2024. They assessed all treatment-related reactions in terms of frequency, type, and severity. They excluded patients lost to follow-up or updosing and stratified the remaining patients by those who discontinued treatment vs those who reached maintenance for all foods.
Those who discontinued treatment included 8.2% receiving oral immunotherapy for milk, 7.3% for sesame, 6.1% for egg, 5.2% for tree nut, and 5.1% for peanut. The overall discontinuation rate was 5%. (Some patients were receiving oral immunotherapy for multiple allergens, so there is overlap by allergen discontinuation rates.)
After adjusting for gender, age, and comorbidities, results revealed that patients undergoing oral immunotherapy for milk had more than twice the odds of discontinuing treatment (OR, 2.68; P < .05). The average incidence of severe reactions was 13%, but incidence was higher for milk (22%), sesame (20%), and egg (25%).
About 1 in 5 patients (20%) who discontinued therapy had any reaction compared with 5.2% overall and 4.0% of those who reached maintenance.
'Patients who discontinued oral immunotherapy had similar frequencies of experiencing mild reactions compared to those who reached maintenance but a higher incidence of moderate and severe reactions,' the researchers reported. Those who discontinued treatment also 'had a higher frequency of reactions to oral immunotherapy doses, including higher frequency of the top three reported symptoms of reaction: Mild abdominal pain, emesis or diarrhea, and pruritus compared to the overall mean of those who reached maintenance.'
Mild abdominal pain was reported in 5.5% of those who discontinued compared with 1.3% overall and 0.9% of those who reached maintenance. Vomiting or diarrhea occurred in 4.5% of those who discontinued treatment compared with 0.4% overall and 0.3% who reached maintenance. Pruritus occurred in 4.9% of those who discontinued compared with 2.1% overall and 1.9% of those who reached maintenance.
'The number of patients is very impressive and adds to the strengths of this retrospective study,' Jonathan Tam, MD, medical director of the Gores Family Allergy Center at Children's Hospital Los Angeles, Los Angeles, told Medscape Medical News . He also noted that the rate of patients who discontinued oral immunotherapy overall was lower than published rates in clinical trials, but the rate of severe reactions was conversely higher.
'Even given this rate of severe reactions, the discontinuation rate was generally low,' Tam said. 'Overall, the findings make sense and are a practical guide to helping patients make decisions oral immunotherapy.'
The authors did not report receiving external funding or having any disclosures. Tam was not involved with the study but is working with Latitude in a Children's Hospital of Los Angeles clinic.
