Published Online: September 5, 2016
Oral immunotherapy is a promising approach to treating food allergies, allowing patients to build up tolerance by consuming the food in initially small and gradually increasing amounts. However, many patients have hypersensitivity reactions during the desensitization process, forcing them to discontinue therapy. One appealing new approach to decreasing reactions in highly allergic patients is to add omalizumab, an anti-IgE antibody approved for use in severe asthma and chronic urticaria.
In the current issue of The Journal of Allergy and Clinical Immunology (JACI), Lynda Schneider and colleagues examine the efficacy of omalizumab in facilitating peanut desensitization in 37 highly allergic patients. The double-blind, placebo-controlled study took place at four U.S. centers and allocated patients to 12 weeks of treatment with either omalizumab or placebo in a 7:2 ratio. Subjects then underwent a rapid one-day desensitization of increasing doses of peanut up to a maximum single dose of 250 mg of peanut protein (equivalent to about one peanut) if tolerated. Peanut dose was then increased weekly to 2000 mg daily over an additional eight weeks. The study drug was then stopped, and subjects continued on daily peanut for an additional six weeks. They were then challenged to 4000 mg of peanut protein (equivalent to approximately 17 peanuts). Those who passed the challenge continued on this peanut dose until the end of the study.
Three quarters of highly peanut-allergic patients treated with omalizumab for 12 weeks were able to tolerate a single dose 250 mg of peanut protein on the first day of desensitization. A similar proportion progressed to 2000 mg of protein within eight weeks and maintained this desensitized state for up to 33 weeks after discontinuing omalizumab. Only one of eight placebo treated patients was able to meet these endpoints. Overall, rates of reactions were acceptable, and severe reactions were rare.
This study indicates that omalizumab allows rapid desensitization to peanut during oral immunotherapy and may be an attractive therapy for patients with severe peanut allergy.
The Journal of Allergy and Clinical Immunology (JACI) is an official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.