By Amy Norton
health day reporter
THURSDAY, May 11, 2023 (HealthDay News) — A “peanut patch” worn on the skin may help protect toddlers who have life-threatening peanut allergies, according to a new clinical trial.
The patch is a form of immunotherapy, which means it exposes peanut-allergic children to tiny bits of peanut protein over time, in an effort to train the immune system to tolerate it better.
In the trial, researchers found that among toddlers who wore the peanut patch every day for a year, two-thirds had a significant reduction in their sensitivity to peanut protein: they could eat the equivalent from one to four peanuts without suffering an allergic reaction.
Although it may look like peanuts, experts say the level of tolerance is important.
The goal of immunotherapy is to prevent a severe reaction if a child accidentally ingests a small amount of peanut, said Dr. Alkis Togias of the US National Institute of Allergy and Infectious Diseases.
“It’s a positive study,” said Togias, who wrote an op-ed published with the results May 10 in the New England Journal of Medicine.
The patch tested in the trial, called Viaskin, is being developed by French biotech company DVB Technologies, which funded the research. It is not yet approved by the United States Food and Drug Administration.
If approved, Togias said: “I think that would only be a good thing.”
An estimated 2% of American children are allergic to peanuts, and for the most part the allergy continues into adulthood. This makes it the most common food allergy in children and the third most common in adults, according to the nonprofit organization Food Allergy Research and Education (FARE).
People with peanut allergies can suffer reactions, sometimes severe, from ingesting even a small amount of food – the amounts that are usually hidden in processed or prepared foods. They (or their parents) should therefore read food labels carefully and take other precautions to avoid exposure to peanuts.
But it’s not easy, says Togias, and accidents happen.
As for treatment, there is an oral form of immunotherapy approved by the United States Food and Drug Administration for peanut allergy, called Palforzia. It is a peanut flour product that can be mixed into foods, such as applesauce. But it is only approved for children 4 years and older.
“There are currently no FDA-approved treatment options for toddlers younger than 4 years old,” said Dr. Matthew Greenhawt, principal investigator of the new trial.
Oral immunotherapy is being studied for toddlers with peanut allergy. But Greenhawt said it’s always good to have multiple options on the table.
“What works for one family may not work for another,” he said.
Additionally, the patch approach may have fewer side effects, according to Greenhawt, a professor of pediatrics at Colorado Children’s Hospital/University of Colorado School of Medicine.
The patch, he said, “takes advantage” of the fact that the skin is the body’s largest immune system organ. This means that a smaller dose of peanut protein can be used, helping to circumvent the systemic side effects sometimes caused by oral immunotherapy – such as upset stomach, throat irritation and shortness of breath. .
These types of issues rarely occur with the patch, said Greenhawt, who is also a medical adviser at DBV Technologies.
The trial involved 362 toddlers, ages 1 to 3, who were randomly assigned to wear either the peanut patch or a placebo (inactive) patch every day for a year. Overall, 67% of the children on the actual treatment reached the end goal of the trial: their immune tolerance developed to the point of being able to ingest the equivalent of one to four peanuts without an allergic reaction.
This compared to 33% of children in the placebo group.
Rashes were the most common side effect with the peanut patch, while just under 2% of toddlers developed systemic symptoms rated as ‘mild to moderate’.
How would that compare to groundnut powder?
It’s hard to judge, Togias said, because no trial has compared head-to-head approaches.
But he pointed to a trial published last year that tested oral immunotherapy for children 1 to 3 years old with peanut allergy. The results, Togias said, suggest that the oral approach may have stronger effects in desensitizing the immune system.
On the other hand, he added, the skin patch may be safer.
A larger question about immunotherapy for peanut allergy, Togias said, is whether there is a time when it can be stopped. Palforzia is taken daily indefinitely, to maintain the immune system’s tolerance to peanut.
Greenhawt said the peanut patch is also designed for daily use, and trials so far (including one in older children) have followed patients for up to three years of use.
Jennifer Bufford, vice president of clinical operations at FARE, agreed that several types of immunotherapy would benefit families.
Bufford also noted that many people with peanut allergies are also allergic to other foods. “It will be interesting to see if the epicutaneous [via the skin] desensitization can be achieved for other common food allergens,” she said.
While there is some positive news on the treatment front, Togias made another point: Peanut allergies can also be prevented by introducing peanut products into babies’ diets once they are start eating solid foods.
More information
FARE has more on peanut allergy.
SOURCES: Matthew Greenhawt, MD, MBA, MSc, professor, pediatrics, section of allergy and immunology, Children’s Hospital of Colorado, University of Colorado School of Medicine, Aurora; Alkis Togias, MD, Branch Leader, Allergy, Asthma, and Respiratory Biology Branch, US National Institute of Allergy and Infectious Diseases, Bethesda, Md.; Jennifer Bufford, MS, vice president, clinical operations, food allergy research and education, McLean, Virginia; New England Journal of Medicine, May 11, 2023