With food allergies on the rise in children, there is a need for combination therapies to decrease the severity of allergic reactions. Researchers recently assessed the effectiveness of the antibody drug omalizumab with oral immunotherapy in treating children with multiple food allergies.
Allergic reactions are characterized by an overproduction of Immunoglobulin E (IgE) antibodies. Under normal circumstances, IgE is released against threats to the body’s immune system. In allergic individuals, IgE is released against normally benign substances, called allergens, resulting in an inflammatory response that can be life-threatening.
Studies have shown that exposure to small amounts of an allergen can reduce the severity of future allergic reactions. A procedure known as oral immunotherapy, which consists of consuming the allergen, has been shown to be effective in individuals with single-food allergies. Few studies have investigated the effect of oral immunotherapy on multi-food allergies, despite multi-food allergies representing approximately 30% of all food allergy cases. The British Medical Journal recently reported on a new study in this field.
Published in the Lancet Gastroenterology and Hepatology, the study investigated the effects of omalizumab on oral immunotherapy in children with multifood allergies. Omalizumab is an anti-IgE antibody that had been previously shown to decrease the severity of single-food allergic reactions. A total of 48 children between the ages 4 to 15 years with multiple food allergies took part in this trial. For a period of 16 weeks, they took either omalizumab with oral immunotherapy or a placebo with oral immunotherapy. The researchers measured desensitization at 36 weeks, which was defined as the ability to eat at least 2g of allergen foods without triggering a reaction.
Omalizumab Increased Desensitization
Of the children in the omalizumab group, 83% achieved desensitization to at least two of their allergens compared to only 33%of the placebo group. No serious adverse events were reported during the study, with only gastrointestinal side effects in both groups. The results suggest that omalizumab can provide a potent boost in desensitizing allergic children to their trigger foods.
The researchers caution that the long-term persistence of desensitization is unknown. Omalizumab’s effectiveness may also be limited in cases with very high IgE levels, such as children with atopic dermatitis. Further research will be required to understand the mechanisms involved and the potential therapeutic uses.
Written by Agustin Dominguez Iino, BSc
References:
(1) Mayor S. Antibody drug improves desensitisation with oral immunotherapy in children with multifood allergy, study finds. BMJ. December 2017. doi:10.1136/bmj.j5736.
(2 Allergy Treatment Spotlight: Oral Immunotherapy (OIT). Food Allergy Canada. http://foodallergycanada.ca/2017/06/allergy-treatment-spotlight-oral-immunotherapy-oit/. Published June 2, 2017.
(3) Facts and Statistics. Food Allergy Research and Education. https://www.foodallergy.org/life-food-allergies/food-allergy-101/facts-and-statistics
