Of all the foods a child can be allergic to, egg is one of the most challenging due to its widespread and sometimes undetectable use in many products.

Yet, physicians must do detective work to figure out the best approach to treat egg allergy.

“We’re relying on tons of different protocols that people are using and relying on products that are being purchased in the grocery store,” said Robert A. Wood, MD, professor of pediatric allergy and immunology at Johns Hopkins University in Baltimore. “Both from the research standpoint and the clinical side, oral immunotherapy [OIT] has continued to grow, but it’s a somewhat dissatisfying state that we’re in.”

Some studies have estimated that 0.9% of children and 1.3% of children younger than 5 years have the allergy. In recent years, physicians have increasingly turned to OIT. But clinicians cannot rely on standardized protocols on OIT for egg allergy. The National Institute of Allergy and Infectious Diseases advises against clinicians using allergen-specific immunotherapy for all food allergies, saying that the safety and therapeutic effect have not been proven. The guidelines, however, on the modality and emerging research on OIT have not been updated since first publishing in 2011.

Over a year ago, a task force was formed by the American Academy of Allergy, Asthma & Immunology and the American College of Allergy, Asthma and Immunology to write immunotherapy guidelines that will provide more clarity for clinicians on OIT for food allergies. A spokesperson for the groups said no release date has been set.

“There isn’t a manual that shows what dose and whether the powdered or baked egg approach will desensitize a child or teen,” said Scott H. Sicherer, MD, director of the Elliot and Roslyn Jaffe Food Allergy Institute at the Icahn School of Medicine at Mount Sinai in New York City.

In many cases, children will outgrow this condition, thus requiring careful assessments of needed treatment to reduce risk. Studies estimate that 4% of children will outgrow their allergy to egg by age 4 years, 37% by age 10 years, and 68% by age 16 years.

Like any treatment, OIT comes with risks, including anaphylaxis, gastrointestinal upset, and the development of eosinophilic esophagitis.

Growing Pains

Much of the work published on OIT for egg is based on relatively small studies, often conducted at a single center, Wood said. The lack of larger trials leaves a lot of uncertainty in what a patient might consume for their immunotherapy, the risks, and the benefits.

Approaches for desensitizing children to eggs include exposure to extensively heated forms of egg or using small amounts of egg white powder.

Sicherer and co-authors over a decade ago published a seminal trial of children aged between 5 and 11 years who received up to 2 g of egg white powder per day in The New England Journal of Medicine. After 10 months, more than half passed an oral food challenge and were considered to be desensitized to egg. None of the children who received a placebo did so. Adverse reactions were oral or pharyngeal.

This year, other researchers published results in the Journal of Allergy and Clinical Immunology: Global, testing a lower, 300-mg daily maintenance dose of egg white protein powder in 15 patients. By the end of the study, 53% of participants developed tolerance to the protein equivalent of a full egg.

A New Drug Comes to Town

Wood was the principal investigator of the OUtMATCH trial, which compared the drug omalizumab for several food allergies with a placebo. The FDA first approved omalizumab in 2003 for allergic asthma. The drug interferes with the harm that can be triggered by excessive immunoglobulin E, a culprit in some food allergies.

The randomized, double-blind, placebo-controlled study enrolled children and adults who were allergic to peanuts and at least two other foods, including egg, milk, wheat, cashew, hazelnut, or walnut. While the trial’s primary endpoint was reaction to peanuts, the drug also fared well on secondary endpoints based on reduced reaction to other allergens.

Among the 46 study participants with egg allergies, 31, or 67%, were able to consume a single dose of egg protein without moderate-to-severe allergic symptoms.

The results led the FDA in 2024 to approve omalizumab for certain cases of food allergy. Researchers are now studying whether this drug could be used in combination with immunotherapy.

Parental Involvement

A parents’ commitment to OIT can be critical to success in treating egg allergy, said Jonathan Tam, MD, medical director of the Gores Family Allergy Center at Children’s Hospital Los Angeles, Los Angeles.

Opting for this approach means parents must enforce what can be burdensome restrictions on the child. These include not running after taking their dose, often for a period of 2 hours. Parents also need to be prepared to have someone watch the child for reactions.

Clinicians must educate parents and children on what to expect. Desensitization can take months, without a guarantee of complete success, Tam said.

“There is a lot of misunderstanding about it; a lot of people go into it with an idea like, ‘This is an absolute cure and it’s easy,’” Tam said.

Allergists said many parents will seek out research on solutions for their children, including OIT. Some may consider trying the protocols at home, without fully understanding potential risks.

With that in mind, pediatricians should make clear to parents the need for supervised care of their children in addressing allergies, Sicherer said.

“Parents might be tempted to try it on their own,” Sicherer told Medscape Medical News. “I emphasize, ‘Do not try this at home.’”

Wood reported receiving funding from Aimmune, ALK, DBV, Genentech, Novartis, Siolta, and Aravax, and consulting fees from Genentech. Tam has been a speaker for ARS Pharma. Sicherer reported having no relevant financial disclosures.

Kerry Dooley Young is a freelance journalist based in Washington, DC. She has covered medical research and healthcare policy for more than 20 years.