A Randomized Controlled Study of Peanut Oral Immunotherapy: Clinical Desensitization and Modulation of the Immune Response
PURPOSE OF THE STUDY.
To determine if peanut oral immunotherapy (OIT) was safe and effective in inducing desensitization in peanut-allergic children. Previous studies on peanut OIT did not include a placebo control.
Studied were 28 children aged 1 to 16 with peanut allergy defined by clinical history of reaction after ingestion, an elevated peanut immunoglobulin E (IgE) level of >15 kU/L, or an IgE level of >7 kU/L if a significant reaction had occurred within the previous 6 months. All subjects had had a positive skin-prick test result to peanut.
Subjects began with an initial dose escalation, with build-up visits every 2 weeks, until a maintenance dose of 4000 mg was reached. Home dosing was continued daily between build-up visits. An oral food challenge (OFC) to peanut occurred around week 48, after at least 1 month of maintenance. Skin-prick testing, cytokine production, and peanut IgG4 and IgE and T-regulatory cell levels were assessed during treatment.
Peanut OIT significantly increased the amount of peanut tolerated at the OFC compared with placebo (mean: 5000 vs 280 mg, respectively; P < .001). Three peanut OIT-treated subjects withdrew because of adverse allergic effects. The peanut-OIT group showed a reduction in skin-test size and interleukin 5 and interleukin 13 levels and increases in peanut IgG4, and IgE, and T-regulatory cell levels.
The results of this study clearly showed that peanut OIT induces desensitization as well as marked changes in the immune response in subjects with peanut allergy.
This study is novel in that it is the first placebo-controlled study of peanut OIT. The study found dramatic efficacy for OIT in inducing desensitization to peanut, as well as concomitant immunologic changes. If OIT is going to become a mainstay of therapy for food allergy, future research will need to address adverse effects of OIT, the optimal duration of OIT, and the efficacy of OIT in inducing long-term tolerance. The sublingual route of immunotherapy for peanut was evaluated in a companion study reported on in the same issue and also showed promise for efficacy and safety (Kim EH, Bird JA, Kulis M, et al. J Allergy Clin Immunol. 2011;127:640–646).
- Copyright © 2011 by the American Academy of Pediatrics