Peanut Oral Immunotherapy in Children with High-Threshold Peanut Allergy.

Background: Approved therapeutics for peanut allergy are not designed for the many patients with allergic reactions to more than one peanut.

Methods: We randomly assigned (1:1) participants 4 to 14 years of age reacting to a challenge of between 443 mg and 5043 mg of peanut protein to peanut oral immunotherapy (P-OIT) using home-measured peanut butter versus peanut avoidance. The primary end point was the difference between groups in the proportion tolerating a two-dose-level increase or 9043 mg of peanut protein. For ingestion participants tolerating 9043 mg, sustained unresponsiveness (tolerance off treatment) was tested after 16 weeks of ad lib ingestion followed by 8 weeks of abstinence.

Results: Of 73 participants, 38 were randomly assigned to P-OIT and 35 to avoidance. Thirty-two of 38 participants in the ingestion group (84.2%) and 30 of 35 in the avoidance group (85.7%) underwent the primary outcome food challenge. The primary analysis with prespecified multiple imputation for missing values showed 100% success for ingestion versus 21.0% for avoidance (between-group difference, 79.0 percentage points; 95% confidence interval [CI], 64.6 to 93.5; P<0.001). All 32 treated and 3 out of 30 avoiders (10%) tolerated 9043 mg. In the intention-to-treat analysis, sustained unresponsiveness occurred in 68.4% (26/38) on P-OIT versus 8.6% (3/35) tolerating 9043 mg among those avoiding (between-group difference, 59.9 percentage points; 95% CI, 42.4 to 77.3). No dosing reactions were greater than grade 1 severity, and no serious adverse events were reported.

Conclusions: In this trial of P-OIT using store-bought, home-measured peanut versus peanut avoidance in high-threshold peanut allergy, those treated achieved significantly higher rates of desensitization with a durable response off treatment. (Funded by the National Center for Advancing Translational Sciences [UL1TR004419] and the National Institute of Allergy and Infectious [U19AI136053]; ClinicalTrials.gov number, NCT03907397.).