• Posted November 9, 2023

Special Toothpaste Might Curb Peanut Allergy in Adults

Researchers are testing a toothpaste that aims to let patients who are sensitive to peanuts and other foods simply brush their allergies away.

Doctors already treat some food allergy patients with oral immunotherapy -- feeding them tiny, portioned and gradually increasing bits of their allergen under supervision for some time.

The new strategy is a twist on that. Called oral mucosal immunotherapy (OMIT), it relies on the lining of the mouth, which has a lot of immune response cells, to desensitize patients.

All they have to do is brush with a specially formulated toothpaste containing peanut protein. Called INT301, it's dispensed in a metered dose and cleans the teeth at the same time.

"The immunotherapy is conveniently administered by just brushing your teeth once a day so you don't have to get an injection,"said researcher Dr. William Berger, a pediatric allergist at CHOC at Mission Hospital, Mission Viejo, Calif. "You don't have to eat something. You don't have to prepare something. You just get up in the morning just like you normally would do and brush your teeth."

Berger is scheduled to present his findings Saturday at a meeting of the American College of Allergy, Asthma and Immunology in Anaheim, Calif. Research presented at meetings is typically considered preliminary until published in a peer-reviewed journal.

To test the treatment, he and his team enrolled 32 adults ages 18 to 55 who had a peanut allergy. Over 48 weeks, some used the actual toothpaste, in increasing strengths. Others were given a placebo.

Researchers said everyone given the peanut toothpaste consistently tolerated the pre-specified highest dose. No systemic reactions, either moderate or severe, were seen.

For participants who had non-systemic reactions, most were oral itching that was mild and temporary.

"In our study, we had really excellent safety data,"Berger said.

Ninety-seven percent of study participants adhered to the treatment, and no one quit. Berger called the toothpaste a safe and convenient option for people with peanut allergy.

This Phase 1 trial was meant to assess safety, adherence and tolerance of the highest dose.

Makers of the toothpaste have submitted results to federal regulators , and the U.S. Food and Drug Administration (FDA) has given the green light to conduct a trial in kids ages 4 to 17.

"We want to protect patients, especially the pediatric population, children, from the accidental exposure to peanuts,"Berger said. "A very, unfortunately, common cause of anaphylaxis in children is ingestion of food allergens that they're allergic to and peanut being the most common."

Researchers could eventually study this in other foods that are a common source of allergens, such as a variety of tree nuts.

In addition to the larger analysis, they also did a smaller one involving five patients who were successfully exposed to larger doses of peanut.

"It's a small number of participants, but that gives us even greater hope that these larger trials are really going to pave the way for the development of this product,"Berger said.

Dr. Joyce Hsu, director of the Brigham and Women's Hospital Food Allergy Center in Boston, called the study -- and the toothpaste -- interesting but said much more data and proof of principle were needed. She was not involved in the research.

She also noted the author's involvement in the company making the toothpaste.

This "means that the study really needs to be externally and independently validated,"Hsu said.

"There is just so much more data on the relative efficacy of oral immunotherapy," she said, adding there is an increasing amount of data on sublingual immunotherapy for food allergies.

Instead of eating a tiny portion of the allergen, that method involves holding a liquid (suspension) containing the allergen under the tongue to absorb it through the mouth.

"Sublingual is something that people are studying because it tends to have fewer reactions than oral immunotherapy,"Hsu said. Though it may also be less protective, it may serve as a bridge for someone to build tolerance to eventually get to oral immunotherapy.

These therapies are meant to increase a person's tolerance so they are less likely to have a severe reaction with an accidental exposure.

"We are always looking for new ways to make life safer for patients with food allergies, but it's always really important to have really good studies that validate both the mechanism and the modality of delivery,"Hsu said. "And we want to make sure that things are not just safe, but also effective so that you're not committing to something without getting benefit out of it."

More information

The U.S. Food and Drug Administration has more on food allergies.

SOURCES: William Berger, MD, pediatric allergist, CHOC at Mission Hospital, Mission Viejo, Calif.; Joyce Hsu, MD, director, Brigham and Women's Hospital Food Allergy Center, Boston; presentation, American College of Allergy, Asthma and Immunology meeting, Nov. 11, 2023, Anaheim, Calif.