Oral immunotherapy can help infants with peanut allergies

A new study revealed that conducting oral immunotherapy on infants younger than 12 months old can safely overcome peanut allergy.

The research, published in The Journal of Allergy and Clinical Immunology: In Practice, was conducted by investigators at the University of British Columbia. In 2019, UBC researchers demonstrated that preschoolers could safely overcome peanut allergies and this study focused on evaluating infants younger than 12 months old.

"This treatment is affordable, very safe and highly effective, particularly if we can get the treatment going before the infant is 12 months old," said Edmond Chan, MD, FRCPC, the study's senior author and clinical professor and head of allergy and immunology in UBC's department of pediatrics at the BC Children's Hospital Research Institute in a statement.

For this study, researchers looked at outcomes for a group of 69 infants among a larger study group of 452 children aged five and under.

Oral immunotherapy is a treatment protocol in which a patient consumes small amounts of the allergenic food—in this case, peanut flour—with the dose gradually increased to a determined maximum amount. Here, the aim was to desensitize the child until they could have a full serving of peanut protein without triggering a dangerous reaction. To sustain their immunity, the child must continue to eat peanut products on a regular basis long term.

For this study, children visited a pediatric allergist in a community or hospital clinic approximately every two weeks to receive their peanut dose. Parents gave the same daily dose at home between clinic visits. After eight to 11 clinic visits, the children had built up to a "maintenance dose" of 300 milligrams of peanut protein, or the equivalent of about 1.3 grams of peanuts.

Symptoms or reactions were documented and parents were advised by clinicians on how to manage reactions at home.

According to the study, 42 infants completed the build-up period plus one year of maintenance dosing. Upon completion, none of them had more than a mild reaction to a 4,000-gram dose of peanut protein, compared to 7.7 per cent of the children aged one to five who completed the protocol.

Seven infants dropped out along the way. Four experienced reactions beyond mild, but none required epinephrine injections. Another 20 did not have their peanut tolerance assessed at the end, either by choice or because of long wait lists.

Infants were shown to be at less risk than toddlers and preschoolers, even before beginning the treatment. In initial testing, only 33.9 percent of infants had a reaction beyond mild, in comparison to 53.7 percent of one-to-five-year-old children.

The study found that the treatment worked equally well for both age groups. After a year of one peanut per day, approximately 80 percent of the children had developed a tolerance for 4,000 milligrams of peanut protein in one sitting—the equivalent of roughly 15 whole peanuts.

"Despite infants showing the best safety, we were still very satisfied with the safety of this treatment for older preschoolers,” Chan said in a statement. “The risk of a severe reaction is much lower than it is for school-age kids. Many of the interventions we use in medicine, such as medications or surgical procedures, carry a small amount of risk that is outweighed by the benefit. If this treatment is performed by well-trained allergists and clinicians then I'm really comfortable with the risk. It's actually very safe."

The first step in trying to prevent peanut allergies among at-risk children is to introduce them to age-appropriate, peanut-containing foods such as peanut butter or peanut flour at around six months of age. If the infant still develops a peanut allergy, Chan’s research suggests that oral immunotherapy can be an effective alternative to avoiding allergens for a lifetime. Trying to avoid allergens altogether carries different risks, such as poor quality of life, social isolation, and anxiety. 

With this new data, the next step recommended by Chan and his team is for practitioners to offer oral immunotherapy as soon as possible after failed food allergy prevention during infancy.