Omalizumab in IgE-Mediated Food Allergy: A Systematic Review and Meta-Analysis

To evaluate the use of omalizumab, an anti-IgE monoclonal antibody, in the treatment of patients with IgE-mediated food allergy

This systematic review and meta-analysis identified 953 patients (children and adults of any age) across 36 studies with clinician-diagnosed IgE-mediated food allergy to single or multiple foods. Study participants were treated with omalizumab as monotherapy or as an adjunct to oral immunotherapy (OIT) for food allergy.

A registered systematic review of literature was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify randomized clinical trials, controlled clinical trials, and observational studies through December 2020 that investigated use of omalizumab monotherapy or omalizumab + OIT in the management of IgE-mediated food allergy. Risk of bias was assessed using the Cochrane risk of bias tool and ROBINS-1 scale.

Meta-analysis was performed to compare the effect of omalizumab treatment to placebo or preomalizumab treatment of outcomes related to food tolerance, successful desensitization, changes in allergen-specific biomarkers, quality of life, and safety.

Literature review identified 36 total studies (9 randomized clinical trials, 19 controlled clinical trials, 8 observational studies comprising approximately 1000 subjects). Omalizumab was administered as monotherapy in 12 studies and as an adjunct to OIT in 24 studies. There was an increase in the tolerated dose of multiple foods in patients who received omalizumab monotherapy (risk ratio = 24.88; 95% confidence interval, 6.35–97.45; I 2 = 0%) or omalizumab + OIT (risk ratio = 1.72; 95% CI, 1.16–2.55; I 2 6%). Omalizumab treatment also increased rates of successful desensitization and improved quality of life metrics for both patients and parents across multiple study time points. Although there was no significant decrease in food-specific or total IgE levels in either omalizumab monotherapy or omalizumab + OIT patients, omalizumab treatment was associated with increased IgG4 levels. Finally, there were no major safety concerns in either omalizumab monotherapy or omalizumab + OIT studies.

Overall, this meta-analysis provides evidence for the efficacy and safety of omalizumab in facilitating some degree of tolerance and desensitization to single or multiple foods in patients with IgE-mediated food allergies.

Food desensitization with oral immunotherapy has emerged as a promising treatment of IgE-mediated food allergy that expands patients’ management options beyond simply allergen avoidance. However, patients undergoing OIT experience an increased incidence of allergic reactions, which may be treatment limiting. Thus, there has been substantial interest in the use of biologics such as omalizumab to facilitate food allergy treatment. Apart from OIT, monotherapy with a biologic agent may also offer an attractive option to improve margin of safety without the risk of OIT-associated reactions. This study was the first systematic review and meta-analysis to demonstrate the efficacy and safety of omalizumab treatment as either monotherapy or adjunctive therapy to OIT in patients with IgE-mediated food allergy.

Questions remain as to how omalizumab-facilitated OIT will compare with omalizumab monotherapy in the treatment of food allergy, questions which will hopefully be answered with the completion of the eagerly anticipated phase III OUtMATCH (Omalizumab as Monotherapy and as Adjunct Therapy to Multiallergen OIT in Food Allergy Participants; ClinicalTrials.gov Identifier NCT03881696).