Oral immunotherapy for children with a high-threshold peanut allergy.

BACKGROUND

Between 25% and 30% of children with peanut allergy (PA) have a relatively high-threshold peanut allergy (HTPA), with a single maximal tolerated dose (SMTD) higher than 100 mg of peanut protein (PP). However, this threshold may decrease with time, age, exercise, illness, sleep deprivation, and other covariates.

OBJECTIVE

To explore the feasibility of a simplified oral immunotherapy (OIT) protocol in a group of children with HTPA.

METHODS

Children with PA with an SMTD higher than 100 mg were placed on a 40-week OIT protocol of either 300 mg/d of PP or 100 mg/d for 20 weeks followed by 300 mg/d for 20 weeks. A repeat open peanut food challenge was performed after 40 weeks of treatment and at a 6-month follow-up visit. After the 40-week challenge, all children received a maintenance dosage of 2 gPP 3 times a week.

RESULTS

A total of 28 children with HTPA were enrolled, with 56% boys, 89% younger than 6 years old, and a mean SMTD of 304 mg (95% confidence interval 229-378). All were placed on the described OIT protocol. Overall, 2 children were not compliant and 3 had allergic reactions at home on the dose previously tolerated in clinic, 23 completed the 40-week protocol, and all were able to consume 2 g of PP. The mean tolerated dosage at the 6-month follow-up was 8 g. This enabled most children age-appropriate dietary inclusion of peanut-containing products.

CONCLUSION

In children with HTPA, a simple, fixed-dose OIT can be both safe and efficacious.