PURPOSE OF THE STUDY.
The goal of this study was to establish the efficacy of oral immunotherapy (OIT) for the desensitization of children with peanut allergy.
Children ages 7 to 16 years with an immediate peanut hypersensitivity reaction and a positive result on skin prick test and double-blind, placebo-controlled food challenge (DBPCFC) to peanut were recruited from allergy clinics and national patient support groups.
In phase 1 of this unmasked, randomized, placebo-controlled trial, children in the active OIT group received 2 to 800 mg/d of peanut protein, and those in the control group continued to avoid peanut. The primary outcome was desensitization, defined as passing a DBPCFC to 1400 mg of peanut protein after 6 months. During phase 2, control participants remaining allergic to peanut received OIT and had a repeat DBPCFC.
Desensitization occurred in 24 (62%) of the 39 children on active OIT (95% confidence interval: 45–78) and in none of the 46 control children (95% confidence interval: 0–9; P < 0.001). Of the active OIT group, 84% (95% confidence interval: 70–93) tolerated at least 800 mg of peanut protein (∼5 peanuts), with a median increase in peanut threshold after OIT of 1345 mg (range: 45–1400 mg; P < 0.001). Similar results were seen in phase 2. Oral pruritus and gastrointestinal symptoms were the most common adverse effects. Wheezing occurred after 0.41% of doses and in 21 children, 1 of whom received intramuscular epinephrine; laryngeal edema occurred after 0.01% of doses and in 1 child. Basophil activation did not differ before and after desensitization.
OIT induced desensitization with a clinically meaningful increase in peanut threshold.
This large, well-designed clinical trial found comparable results to a double-blind, randomized, placebo-controlled study published in 2011. In the earlier study, 16 children in the treatment group (84%) completed 1 year of peanut OIT and tolerated a DBPCFC to 5000 mg of peanut protein, whereas the placebo group tolerated a median cumulative dose of 280 mg of peanut protein (Varshney P, Jones SM, Scurlock AM, et al. A randomized controlled study of peanut oral immunotherapy: clinical desensitization and modulation of the allergic response. J Allergy Clin Immunol. 2011;127:654–660). The 2014 study used a lower cumulative DBPCFC dose (1400 mg) and did not mask group allocation to active treatment or placebo. Although this study did not exclude children with severe asthma or life-threatening reactions to peanut, the numbers of these high-risk children completing the study were not reported. Wheezing and laryngeal edema were not universally treated with intramuscular epinephrine. The 1 participant who used intramuscular epinephrine was withdrawn from the study.
- Copyright © 2014 by the American Academy of Pediatrics