Oral and sublingual peanut immunotherapy is not ready for general use

Abstract

Food oral immunotherapy (OIT) is an investigational peanut allergy treatment aimed to achieve specific oral tolerance induction. Allergic children are given titrated oral (or sublingual) doses of their allergen on a daily basis, unlike in subcutaneous immunotherapy (SCIT). OIT is theorized to cause a shift from a Th2 to a Th1 regulatory environment, reflected by increases in food-specific IgG4/IgE, and the production of FoxP3. Peanut OIT holds special promise because peanut allergy has an unfavorable natural history and is rarely outgrown. A high percentage of the participants experience symptoms during peanut OIT, including anaphylaxis, warranting epinephrine and/or discontinuation of therapy. This is a concerning fact given that the studies have mostly targeted only older children, with less historical reactivity for enrollment. The handful of peanut OIT studies have shown that some participants can be desensitized to peanut, but none have shown that long-term tolerance can be reestablished. Factors predictive of which patients are most likely to succeed and become desensitized through OIT are unknown. Some private practices have begun offering peanut OIT as a therapy. Such practice is potentially dangerous given the safety and efficacy of OIT in randomized controlled clinical trials is still not well established. Therefore, until further investigation emerges that conclusively demonstrates OIT is safe, intermediate and long-term outcomes are better established, the number of participants that experience symptoms is reduced, and proof of concept established in patients of all ages, (irrespective of past reaction severity), OIT is not ready for use in the general allergy practice.