Study on Peanut Allergy Treatment Offers Promise for Allergic Kids

Living with a peanut allergy can feel a lot like navigating a minefield when trying to determine which foods are safe for your child to eat. Whether you are eating out, on a playdate at a friend's house, or traveling with your child's soccer team, the risks of accidental exposure seem to linger around every corner. Despite even the best-laid plans and precautions, accidental exposures can and do happen.

But a new study published in the Journal of Allergy and Clinical Immunology shows promise in reducing some of those concerns peanut allergy families wrestle with every day. By desensitizing kids to peanuts, allergists may be able to reduce the risk that an accidental exposure could end in a trip to the emergency room.

"Unfortunately, even when parents are extremely careful, cross-contaminations and accidental exposures can happen," says Edwin Kim, M.D., MS, lead author of the study and associate professor of pediatrics at UNC School of Medicine. "This study shows that we can safely desensitize the majority of peanut-allergic children and provide some protection against the unexpected."

A Closer Look at the Study and Its Results

This recent study is actually phase two of a four-year clinical trial. Researchers were able to demonstrate that a peanut allergy treatment known as sublingual immunotherapy—or SLIT—is a safe and effective way to offer desensitization to peanuts in allergic kids.

"Back in 2011, we published our first study that showed after one year of treatment with 2 milligrams of peanuts, kids became desensitized," Dr. Kim says. "With this newer study, we wanted to focus more on longer-term results. [In other words], can sublingual immunotherapy really desensitize kids and how long-lasting is that change?"

Although this second study was small—with only 54 children—the results suggest that SLIT is extremely effective in desensitizing the majority of peanut-allergic children, ultimately protecting them from having reactions to unintended peanut exposures.

Nearly 70% of the peanut-allergic children who completed the study's treatment showed protection against accidental exposures and 36% showed full desensitization. In other words, those with full desensitization could tolerate 5,000 mg of peanut protein, or 16 peanuts, without having a reaction.

What's more, the results suggest the treatment tends to last longer than one might expect. A model of the time off of the treatment showed that on average, it would take 22 weeks for the child to become re-sensitized to small amounts of peanuts. This is great news, not only because of the longevity of the protection, but also because it means breaks in treatment will not derail the progress.

"From a parent's point of view, we know with any treatment life happens and it can be challenging to give this treatment every day," Dr. Kim says. "But what we are hoping is that the data shows that if they miss a day or so of treatment, the level of protection still lasts. From a practical aspect, a parent could potentially send their child away to a camp and know protection is there. Likewise, if the child gets sick and cannot take the treatment, we know that threshold is there and that it does not reset to zero."

How This New Treatment Differs From Oral Immunotherapy

Oral immunotherapy includes ingesting small amounts of peanut protein by mouth. SLIT uses a minuscule amount of peanut protein, equivalent to only 1/75th of a peanut kernel, Dr. Kim says. This treatment is taken under the tongue, where it is absorbed into the body.

"This is an important study that furthers our understanding of peanut immunotherapy in young children using a different approach than oral immunotherapy," says David Stukus, M.D., professor of clinical pediatrics in the division of allergy and immunology at Nationwide Children's Hospital. "[It also] offers new insight into using sublingual immunotherapy, which appears to have similar efficacy with decreased risk for causing allergic reactions."

In fact, during the study, only 4% of doses resulted in side effects—most of which were limited to itchiness in the patient's mouth. There weren't any side effects that called for treatment with epinephrine (EpiPen).

Another benefit to this therapy is that it uses a smaller dose of peanuts than oral immunotherapy and is also easier for kids to tolerate. They simply hold the liquid under their tongue for a minute and then swallow it, making it an extremely easy process that even young children can handle.

"Until we can get to a cure, the more options we have for patients and families to get them to the goals they want without adding a burden, the better it will be," Dr. Kim says. "What we don't want is to add to the burden food allergy families already experience. Sublingual immunotherapy may be something that can fit that bill—something that can provide the protection without increasing the burden or risk."

What Does This Mean for the Future of Peanut Allergies?

While sublingual immunotherapy requires a different protocol and process than traditional oral immunotherapy, Dr. Stukus says we may see increased adoption of the treatment in the next couple of years—especially since some allergists are already offering "off-label" immunotherapy.

That said, peanut immunotherapy should only be pursued with the guidance and supervision of a board-certified allergist. It is also important for parents to realize that this study demonstrates what the existing body of evidence consistently demonstrates—peanut immunotherapy of any kind does not offer a cure for the majority of people who pursue treatment, Dr. Stukus says.

"Most children can achieve desensitization and reach a maintenance dose, which can increase the amount they would need to eat on accident to cause a severe allergic reaction," he says. "Use of sublingual immunotherapy also appears to be safer compared with oral immunotherapy, but it will be important to see larger studies in a wider variety of children to better understand when and how to utilize it in clinical practice."

Another big question is whether peanut-allergy families are even willing to try any sort of immunotherapy treatment. "As an allergy parent, I see its value—especially for those with extremely severe peanut allergies," says a New Jersey mother of three, two of whom have allergies. "My children are allergic to other foods as well, so our avoidance procedures would still be needed."

The mom goes on to say she'd be hesitant to try this therapy, adding she was always afraid to even try peanut tolerance tests. "If my children had extremely severe allergies (such as being airborne allergic), I might feel differently. But I am always going to use avoidance and precaution." She says her 13 and 11-year-old children are now old enough to read labels and ask questions before eating anything.

Where Can You Find SLIT Treatment?

While the treatment option used in the study is not widely available among allergists in private practice, Dr. Kim says there is a company developing a form of sublingual immunotherapy for peanut allergies. It uses a tiny tablet that dissolves under the tongue—rather than a liquid placed under the tongue as used in this study.

"A safety study using this tablet is currently underway and hopefully will quickly lead to a treatment study that the Food and Drug Administration (FDA) can consider," he says. "There [also] are some clinics that are currently using available liquid peanut extracts similar to our study as an 'off-label' treatment for peanut allergy. Overall, the sublingual approach seems to be simple with good safety so I anticipate there to be growing interest in this in the near future."

He adds one benefit of clinics using the sublingual approach now is it can get to patients much faster than waiting for large clinical trials to be completed. But precautions need to be taken with regard to safety, distribution, and administration, as this approach may not be right for everyone.

"At this point, it is all about options—food allergies affect every family differently," Dr. Kim says. "Each family is looking for different things. But the more options we have for families to choose from, the better for all food allergy families."