Drug cuts risk of allergic reactions to peanuts and other foods

Severe food allergies can cause anxiety over normally fun activities like eating with other people. MP Studio / Adobe Stock

Food allergies affect more than 7% of children nationwide. For those with severe allergies, normally fun activities like eating out or sampling desserts can cause a lot of anxiety. Even small traces of nut, egg, wheat, or other common foods could cause dangerous allergic reactions. These severe reactions, called anaphylaxis, can quickly lead to trouble breathing, tightened throat, and a rapid drop in blood pressure.

To prevent such reactions, affected people have to avoid allergy-triggering foods. Many need to carry rescue medications in case of accidental ingestion. The only treatment, called oral immunotherapy, is onerous and has significant side effects. It involves eating tiny daily doses of allergy-causing foods under a doctor’s supervision. Doses are gradually increased to build up tolerance, which can take months. Although many allergy specialists use this approach, the only oral immunotherapy approved by the U.S. Food and Drug Administration is for peanut allergy.

Researchers have been exploring a different treatment approach that targets an immune protein called IgE, which plays a key role in allergies. In small clinical trials, a monoclonal antibody that binds IgE, called omalizumab, showed promise for treating food allergy. The drug had previously received FDA approval for treating other conditions, including moderate to severe allergic asthma.

A multistage clinical trial was launched five years ago with NIH support and oversight to test omalizumab for food allergies. In the initial stage of the study, researchers tested to see if omalizumab would be safe and effective in treating patients who had multiple food allergies. The study enrolled 177 children and adolescents, ages 1 to 17, and three adults. All were allergic to peanuts and at least two other specified foods. These were milk, egg, wheat, walnut, cashew, and hazelnut. The participants reacted to less than 100 mg of peanut protein (about half a peanut) and less than 300 mg of the other foods.

Participants were randomly assigned to receive injections of omalizumab or an inactive placebo every two to four weeks for 16 to 20 weeks. Neither participants nor the researchers knew who was receiving medication vs. placebo. The participants were then tested to see if they could tolerate more of their allergy-inducing foods than at the start of the study. Results were reported in the New England Journal of Medicine on February 25, 2024.

The scientists found that 79 of 118 patients who received omalizumab (67%) could eat at least a single 600 mg dose of peanut protein without a moderate or severe allergic reaction. That dose is equal to about 2.5 peanuts. In contrast, only 4 of 59 who received placebo (7%) could safely consume that amount. Similar results were seen for the other foods.

Many omalizumab-treated participants could eat 1,044 mg of peanut protein, or about four peanuts. And 44% could eat over 5,000 mg, or close to 25 peanuts.

On February 16, 2024, omalizumab received FDA approval for the reduction of allergic reactions to one or more foods based on findings from the trial. FDA noted that people who take omalizumab must continue to avoid foods they are allergic to. Future studies will continue to assess omalizumab and oral immunotherapy approaches for people with multiple food allergies.

“People with food allergies and their caregivers need to maintain constant vigilance to avoid foods that could cause a potentially life-threatening allergic reaction. This is extremely stressful, especially for parents of young children,” says Dr. Jeanne Marrazzo, director of NIH’s National Institute of Allergy and Infectious Diseases (NIAID). “Although food avoidance remains critical, the findings show that a medicine can help reduce the risk of allergic reactions to common foods and may provide protection from accidental exposure emergencies.”