A wearable patch could prevent severe allergic reactions in young children with a peanut allergy, according to the results of a promising clinical trial.

The late-stage trial, involving more than 200 children ages 1 to 3 with peanut allergies, found that after wearing the experimental patch for about 22 hours a day for one year, 67% were able to tolerate 300 to 1,000 milligrams of peanut protein: The equivalent of one to four peanuts. He the findings were published Wednesday night in the New England Journal of Medicine.

“Surprisingly, not only did the amount of peanuts increase [tolerance] in these children, but the nature of the reaction also changed. There was a decrease in the number of serious reactions,” said Dr. Matthew Greenhawt, the study’s lead author and director of the Children’s Hospital Colorado Food Challenge and Research Unit.

The patch, a product called Viaskin from biopharmaceutical company DBV Technologies, contains a small dose of peanut protein equivalent to about 1/1,000 of a peanut kernel. A new patch is applied each day and placed between the shoulder blades so that the protein is absorbed by the skin. The immune cells then carry the protein to other parts of the body, where it helps suppress the allergic response, according to the company.

There are no approved treatments for children under 4 years of age with peanut allergies. The Food and Drug Administration has one approved however, for those ages 4-17: a powder called Palforzia that can be mixed into foods like applesauce, yogurt, or pudding. The powder is also intended to reduce the risk of severe allergic reactions by increasing children’s tolerance to peanuts over time.

Viaskin’s trial, however, is the first to study a non-oral option for this younger age group.

Dr. Pharis Mohideen, chief medical officer for DBV Technologies, said Viaskin’s goal is not to make children tolerate peanut butter and jelly sandwiches or to eliminate an allergy entirely.

«We’re trying to build a protective shell for them so that if there’s an accidental exposure to peanuts, they don’t have a reaction, or that reaction is very mild, and you don’t send them to the emergency room,» he said.

Mohideen added that getting children with allergies to a point where they can tolerate various peanut kernels is «absolutely life-changing» and would ease parental anxiety about taking their children to restaurants or on planes.

“If a label says ‘may contain peanuts,’ but you know you can tolerate a whole kernel of peanuts, the likelihood that that product is safe is pretty high,” he said.

Approximately 1 in 50 children in the US have a peanut allergy. TO report 2018 found that the prevalence of peanut allergies in the country had tripled in the previous two decades, but the reasons for this trend are not entirely clear.

Up to 20% of people with a peanut allergy eventually get over italthough some people’s allergies get worse over time.

In Viaskin’s trial, four of the participating young children developed anaphylaxis, an allergic response often characterized by shortness of breath, throat swelling, pale skin, blue lips, fainting, or dizziness. The reactions were not considered serious, although three required epinephrine, an injection better known as an EpiPen.

Greenhawt said most of the side effects in the trial were localized skin reactions.

Other research on interventions for peanut allergy is ongoing. Researchers from the UNC School of Medicine recently completed a phase 2 trial in children 1 to 11 years of age that involved putting a small amount of peanut protein under the tongue. Of the 47 children who completed treatment, 70% could tolerate the equivalent of about three peanuts and 36% could tolerate the equivalent of about 16 peanuts.

Viaskin is also being studied in children 4 to 7 years of age and has previously been studied in adolescents and adults. But Greenhawt said the patch appears to be more effective in young children because younger children’s immune systems are more malleable.

Dr. Kanwaljit Brar, a pediatric allergy and immunology specialist at Hassenfeld Children’s Hospital at NYU Langone, said the majority of her patients with peanut allergies are infants and young children. Older pediatric patients of hers have seen improvements with Palforzia, she added, but it’s not right for everyone because it requires doctor visits every two weeks and isn’t covered by all insurance providers.

The patch could remove some of those barriers to access, Barr said. «I actually have a daughter with a peanut allergy, and this would be a great option for someone like me who is a very busy parent,» she said.

Mohideen said that DBV Technologies eventually plans to submit Viaskin to the FDA for approval, but added that the agency has asked the company to collect more safety data on the patch in both toddlers and children before applying it. There is no specific timeline yet for completing an application, he said.