Real World Data Supports Omalizumab as Monotherapy for IgE-Mediated Food Allergy

Real-world evidence shows the efficacy and tolerability of omalizumab used as monotherapy or in conjunction with oral immunotherapy to treat an IgE-mediated food allergy.

“This study involved a substantial cohort of adult patients throughout Europe and highlights the significant efficacy of OMA in managing food allergies,” wrote investigators, led by Aikaterina Alexiou, MSc, from Charité Universitätsmedizin in Berlin, Germany.

As of now, no approved therapies exist in Europe for adults with IgE-mediated food allergies. Patients must avoid their allergen daily and rely on emergency medication, such as epinephrine, when needed. Oral immunotherapy is another option, licensed only as Palforzia in the United States and Europe to treat peanut allergy in children.

A little over a year ago, the US Food and Drug Administration (FDA) approved omalizumab (Xolair), a humanized monoclonal anti-IgE antibody that could reduce allergic reactions to multiple foods after accidental exposure.2 Xolair was approved as an injection for an IgE-mediated food allergy in adults and children ≥ 1 years to reduce allergic reactions.

However, omalizumab is not yet approved for IgE-mediated food allergies in Europe, only indicated for the treatment of severe persistent asthma, chronic spontaneous urticaria, and severe chronic rhinosinusitis.3

Patients experiencing anaphylaxis due to insect venom or food exposure can only receive omalizumab off-label when not suffering from coexisting chronic spontaneous urticaria or severe asthma.1 Investigators conducted a retrospective analysis of real-world data from patients across European countries who received omalizumab for food allergy and food-induced anaphylaxis.

The team included patients treated between 2002 and 2022, using data from the Anaphylaxis Registry and cooperative centers in Spain, Germany, and Switzerland. Participants completed structured questionnaires covering demographics, medical and food allergy history, diagnostic results (including oral food challenges), omalizumab treatment (type, dosage, safety), and oral immunotherapy details. Investigators also assessed laboratory test results, including total IgE, specific IgE, and basal serum tryptase, prior to treatment initiation.

Treatment responders included those with a negative oral food challenge (group A), reduced severity during challenge (group B), or no anaphylactic reactions (group C). Non-responders experienced repeated anaphylactic reactions during treatment, and partial responders had ≤1 food-induced reaction despite therapy.

The study included 62 patients: 52 from the Hospital Vall D’Hebron in Barcelona, Spain, 5 from Charité Universitätsmedizin, 4 from University of Leipzig, Germany, and 1 from University Hospital Basel in Switzerland. Most were female (52.9%), all Caucasian (100%), and the mean age was 30.6 years at treatment initiation (range: 9 – 59 years). Comorbidities included allergic rhinoconjuctivitis (69.4%), asthma (54.8%), atopic dermatitis (11.3%), and chronic spontaneous urticaria (8%).

Mean IgE levels were 606.6 kU/1 (median 289 kU/1), and mean tryptase levels of 4.4 μg/l (median 3.97 μg/l). Food allergy diagnosis was based on prior ≥ Grade 2 anaphylaxis (Ring & Messmer score), confirmed in 12.9% via food challenges and in 3.2% through medical history due to symptoms like urticaria.

Common allergens included tree nuts (43.5%), cow’s milk (41.9%), fruits (40.3%), and vegetables (40.3%). Others included legumes (6.5%), fish (6.5%), crustaceans (3.2%), wheat (3.2%), and seeds (1.6%).

Overall, 27.4% (n = 17) underwent omalizumab monotherapy, typically 300 mg subcutaneously every 4 weeks; 72.6% (n = 45) received omalizumab alongside oral immunotherapy. Omalizumab was used adjunctively for cow’s milk (35.5%), peach juice (32.6%), and eggs (5%).

Nearly all patients (98.4%) reported excellent safety, although 1 patient discontinued due to recurrent abdominal pain. Most (77.4%) continued treatment with or without oral immunotherapy for a mean of 5.5 years; 12 received it for > 7 years.

The study found 83.9% were responders, with 9.7% in group A (negative oral food challenge test), 9.7% in group B (reduced severity), and 64.5% in group C (no anaphylactic reactions). Only 1 patient was a non-responder, and 14.5% (n = 9) were partial responders.

Ultimately, 82.4% of those who underwent omalizumab monotherapy were responders. Among those treated with omalizumab and oral immunotherapy, response rates were 90.1% (cow’s milk), 75% (peach juice), and 100% (eggs).

“Notably, our study shows that OMA, particularly when combined with OIT, achieves higher response rates,” investigators concluded. “Regional variations in sensitization patterns underscore the need for tailored allergy treatment across populations.”

References

1. Alexiou A, Carreras-Kàtcheff S, Hartmann K, Treudler R, Tassinari P, Cardona V, Worm M. Efficacy of omalizumab in food allergic adults - A retrospective analysis. World Allergy Organ J. 2025 Apr 3;18(4):101048. doi: 10.1016/j.waojou.2025.101048. PMID: 40235675; PMCID: PMC11999602.

2. FDA Approves First Medication to Help Reduce Allergic Reactions to Multiple Foods After Accidental Exposure. US Food and Drug Administration. February 16, 2024. https://www.fda.gov/news-events/press-announcements/fda-approves-first-medication-help-reduce-allergic-reactions-multiple-foods-after-accidental#:~:text=Today%2C%20the%20U.S.%20Food%20and,accidental%20exposure%20to%20one%20or. Accessed April 24, 2025.

3. Xolair. European Medicines Agency. https://www.ema.europa.eu/en/medicines/human/EPAR/xolair. Accessed April 24, 2025.