Monday, February 9, 2015
Biologics and food allergy
Food allergy is an immune-mediated response to food proteins leading to symptoms affecting the skin, gastrointestinal tract or respiratory tract. Up to 8% if children and 5% if adults self-reported an allergy to at least one food. The incidence of food allergy has steadily increased over 18% between 1997-2007, suggesting that environmental influences may play a role. Despite this increase in prevalence, there are currently no approved treatments beyond allergen avoidance and treatment of reactions to accidental ingestion. Though the incidence of food allergy-related mortality is low, avoidance and fear of accidental ingestion significantly impairs the quality of life for children with food allergy and their caregivers. In their review, Bauer et al discuss the mechanisms that contribute to allergy with emphasis on future targets for biologics for the treatment of IgE mediated food allergy (J Allergy Clin Immunol 2015; 135(2): 312-323).
Recently there has been increased interest in the use of biologics which are selective immune antagonists for the treatment of allergic diseases, particularly asthma. Dupilumab, a biologic that binds to IL-4Rα and blocks the Th2 cytokines IL-4 and IL-13 activity has been successful in clinical trials for the treatment of asthma and atopic dermatitis. However, relatively few studies have investigated applications of biologics for the treatment of food allergy and no reported clinical trials have investigated the effectiveness of anti-Th2 cytokine treatments in context of food allergy. Recent basic and clinical studies have identified attractive new targets for food allergy therapeutics, including epithelial cell-derived mediators (such as IL-33 and TSLP), IgE-binding receptors (such as CD23) and IgE signaling pathways. A promising therapeutic for the treatment of food allergy is the drug omalizumab which binds IgE and reduces serum levels by 99%. If successful, omalizumab could allow for the use of rapid dose escalation protocols for allergen immunotherapy for food allergic patients. A new drug similar to omalizumab, ligelizumab is an anti-IgE antibody that binds free serum IgE, but with up to 12-times higher affinity, making it much more potent. Phase II trials are planned to assess the clinical efficacy of ligelizumab in subjects with atopic dermatitis and asthma.
Despite the increasing prevalence of food allergy and adverse impact on human health and quality of life, there is an unmet need for effective therapeutic options to treat food allergy. The authors detail a variety of potential treatment options for food allergy, although most studies have focused on asthma, allergic rhinitis, and atopic dermatitis, and future studies are needed to determine the effects on food allergic patients.