Omalizumab Approved to Prevent Accidental Food Allergy Reactions

Jennifer Middleton, MD, MPH
Posted on February 26, 2024

Parenting a child with a food allergy—or living with a food allergy as an adult—can feel perpetually stressful. Patients and their families must remain constantly vigilant for the presence of their allergen(s) in their surroundings knowing that an accidental exposure can be life threatening. Although no cure for food allergies is yet available, a new treatment that can markedly decrease the chance of a life-threatening event after an accidental exposure may provide peace of mind to these patients and families.

Omalizumab (Xolair) is an established monoclonal antibody treatment for allergic asthma, chronic hives, and nasal polyps. The U.S. Food and Drug Administration (FDA) approved omalizumab earlier this month for people one year and older "who [are] allergic to peanut and at least two other foods, including milk, egg, wheat, cashew, hazelnut or walnut.” The FDA based its decision primarily on an interim analysis of a phase III trial of 168 patients, one to 55 years of age with the previous multiple food allergies, who were randomized to 16 to 20 weeks of either placebo or omalizumab. There were “66.7% [who] achieved the primary endpoint (>600 mg peanut protein) compared with [6.7%] on placebo (odds ratio (OR) 28.0 (95% CI 9.2-112), P<0.0001). Similar results were seen for the other foods at a threshold of >1000 mg (tree nuts (ORs 9.53-21.9), milk.” The patients randomized to omalizumab tolerated these portions of their food allergies without “symptoms like body hives, persistent coughing, or vomiting.” (600 mg of peanut protein is about 2.5 peanuts; 1,000 mg is roughly equivalent to 3.5 cashews, 0.25 of an egg, and 30 cc of milk.) Patients using omalizumab will still need to avoid intentional exposure to the foods they’re allergic to, and they will also still need to be prepared with an epinephrine auto-injector (Epi-Pen) because sizable proportions of participants in the study still had a reaction after allergen exposure.

Approximately 1 in every 16 U.S. adults has a food allergy, although this proportion is not evenly distributed across gender and ethnic groups. Women (7.8%) have higher rates than men (4.6%), and non-Hispanic Black adults (8.5%) have higher rates than Hispanic (4.4%), non-Hispanic White (6.2%), and non-Hispanic Asian (4.5%) adults. The populations with higher rates of food allergy are also the populations more likely to be living in poverty and/or have insufficient health insurance coverage in the United States. Given omalizumab’s cost ($2,900 a month for children and $5,000 a month for adults) and its limited distribution drug status, there is significant risk of inequities regarding its access and affordability. It remains to be seen whether Genentech, the subsidiary of Novartis and Roche who distributes Xolair, will provide sufficient assistance through its current financial assistance programs.

Certainly, though, the use of omalizumab may be life changing to the “people with allergies – and their families – [who] live with consistent anxiety about exposure to allergens and often avoid dining out and other social situations.” We can ensure that our patients who are potentially eligible for this treatment are referred to specialists with access to omalizumab—and we can also remind them that this treatment is not a substitute for continued caution. If you’d like to read more, read the AFP’s STEPS (safety, tolerability, effectiveness, price, and simplicity) article for omalizumab’s 2005 approval for asthma, a 2023 AFP article, “Chronic Asthma Treatment,” that discusses omalizumab for that indication, and another 2023 AFP article, “Food Allergies: Diagnosis, Treatment, and Prevention.” An AFP By Topic on Allergy and Anaphylaxis is available if you’d like to dig deeper.