Published online: February 20, 2019
A drug to improve the control of allergic asthma has proved capable of raising a protective barrier even against anaphylaxis, the more severe form of food allergy. Allergy researchers at the Bambino Gesù Pediatric Hospital observed reactions to various food allergens in a group of children during treatment with the drug omalizumab. The results of the study have just been published in The Journal of Allergy and Clinical Immunology: In Practice by Fiocchi et al.
The researchers at the Pediatric Hospital of the Holy See have studied a group of 15 children and teenagers, aged between 6 and 18, suffering from severe allergic asthma associated with complex forms of food allergy (immediate reactions to 2 or more foods and/or unfeasibility of oral immunotherapy). The study lasted almost 3 years: during this period reactions to various food allergens were observed before and after the start of treatment with omalizumab, an active ingredient used to treat persistent severe allergic asthma. The drug acts directly against immunoglobulin E (IgE), which underlies asthmatic crises, preventing inflammatory attack. Of documented efficacy on the front of allergic asthma and chronic urticaria, to date the effects of omalizumab on other forms of allergy have been poorly investigated. The study has shown its positive effects also on severe food allergy, i.e. on the level of tolerability of food allergens during treatment for severe asthma.
The patients enrolled in the research showed immediate allergic reactions to 37 foods. Eighty per cent of them had already faced episodes of anaphylaxis. The researchers tested the levels of reactivity for 23 different foods (including milk, eggs, wheat, and hazelnut) before and after the start of treatment with omalizumab. The comparison of the data showed an increase in the allergen tolerance threshold from an initial 460 mg of protein to 8192 mg, which significantly reduced the risk of anaphylactic shock in case of involuntary contact with "forbidden" foods. In fact, during the observation period, the number of reactions to accidental allergen ingestion fell from 47 to 2 episodes recorded. Thanks to the protective action of the drug, over 70% of tested foods (15 out of 23) have been safely reintroduced into the children's diet, without the need for oral immunotherapy procedures. The remaining foods were almost completely tolerated. According to the opinion of parents and patients, expressed through a questionnaire, the quality of life increased on average by 40%.
"The study has allowed us to understand that with omalizumab food allergy reduces its danger and that very risky doses of food can become tolerated, almost eliminating the risk of anaphylactic shock", explains Alessandro Fiocchi, Head of Allergy of the Bambino Gesù Pediatric Hospital and Chair of the Food Allergy Committee of the World Allergy Organization. "With the administration of the drug the child gains a state of tolerance that allows him to breathe, eat and get in touch with allergens, even the most dangerous for him, without having damage. The results of our research now open the way to prospective studies on the appropriateness of using the treatment also for selected cases of patients with food allergy who do not have asthma”. Omalizumab is not included in any food allergy management guideline. Further studies are needed to evaluate its cost-effectiveness.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.