• Posted April 28, 2025

Exposure Therapy For Peanut Allergy Effective In Adults

Adults with peanut allergies can be safely treated using exposure therapy to increase their resistance, new clinical trial results show.

More than two-thirds of participants (67%) gained the ability to tolerate at least five peanuts without an immune reaction, researchers report in the journal Allergy.

This is the first trial to test exposure therapy in adults, researchers said. Such therapy is typically performed in children, whose immune systems are still evolving.

Under exposure therapy, patients are given daily doses of their food allergen to build up their tolerance.

“Constant fear of life-threatening reactions place(s) a huge burden on people with peanut allergy,” said senior researcher Stephen Till, a professor of allergy at King’s College London in the U.K. “The only way to manage a peanut allergy is strict avoidance and treatment of allergic reactions, including with adrenaline.”

While peanut immunotherapy is known to be effective in kids, Till said in a news release that this trial provides preliminary evidence that adults can also be desensitized, which improves their quality of life.

“The average tolerated dose of peanuts increased 100-fold over the course of the trial,” he said.

For the clinical trial, 21 people age 18 to 40 with peanut allergy were treated with daily doses of peanut flour mixed in their food.

The goal was for patients to achieve a daily dose of one gram of peanut flour without reaction for at least four weeks. They then were randomly assigned to be challenged either with a dose of peanut or a placebo.

Patients then continued daily dosing for at least three more months before leaving the trial.

“We are very pleased with the results,” Till said. “The efficacy rate is broadly in line with peanut oral immunotherapy trials in children." 

The next stage of research will be confirming this in larger trials. Researchers will also be looking to identify adult patients would be most likely to benefit from oral immunotherapy and whether it can lead to long-term tolerance in this age group.

People with peanut allergies live in constant fear that something they eat will have been inadvertently exposed to peanut, said lead researcher Hannah Hunter, a specialist allergy dietitian from Guy’s and St Thomas’ NHS Foundation Trust in the U.K.

“Everyday situations such as eating in restaurants and social events are anxiety provoking and our patients tell us that the condition also affects travel choices and career options,” she said in a news release.

“We found that quality of life significantly improved after oral immunotherapy and fear of food also decreased,” Hunter added. “Many participants who completed the trial told us that the treatment had been life-changing and they were no longer living in fear.”

One participant in the trial, a 28-year-old man named Chris, had suffered from peanut allergies since he was a baby.

“I’m so proud to have been part of this trial and so happy to say that I used to be allergic to peanuts but thanks to this trial, this is no longer a concern,” Chris said in a news release. “Me and my family were always anxious that even a trace of peanut could be life-threatening.”

He called the trial "an interesting experience," noting that he had always "associated the taste and smell of peanuts with fear and death."

Chris said he began the trial by ingesting a small amount of peanut flour with yogurt and by the end was able to eat four peanuts in a single sitting. 

"Now, I have four peanuts every day with my breakfast to maintain my immunity,” he said.

“Before, a tiny mistake could have life-threatening impacts but now I don’t have the fear that I might collapse and die from eating a takeaway,” Chris concluded.

More information

Children’s Hospital of Philadelphia has more on exposure therapy for food allergies.

SOURCE: King’s College London, news release, April 23, 2025