Pediatric Allergist at Emory University & Children’s Healthcare of Atlanta, Dr. Brian Vickery, talks about a new way to combat allergic reactions in children.
Interview conducted by Ivanhoe Broadcast News in 2023.
Peanut allergies are becoming more and more common. First of all, is this true? And if so, why?
VICKERY: Well, we can spend the rest of the afternoon on that question. It is indeed true that peanut allergies are more common than they used to be. That’s a perception that many people have, but actually, the evidence from the scientific literature, from large studies substantiates the fact that probably over the last 10 to 15 years, peanut allergies have tripled in prevalence.
Why is that?
VICKERY: Well, we don’t know the precise answer. We’re getting a little bit closer to understanding why, but it appears that it’s largely a combination of environmental factors that in concert work towards the development of allergic responses in susceptible hosts.
How are peanut allergies typically treated? If you can, talk about the phases. How are these typically treated?
VICKERY: The way we address peanut allergy depends on a number of factors; the age of the child, the severity of the presentation, and in part, the parent’s wishes. So many patients after diagnosis are still treated with avoidance. That is, we coach them on how to carefully eliminate all traces of peanuts from their diet, and then every patient receives an emergency kit containing medications like antihistamines and auto-injectable epinephrine to be used in the event of an accidental exposure to peanuts that causes an allergic reaction. Historically that was really all we ever had to offer any patient of any age. Now, because of research that’s been going on over about the last 20 years, we have the first FDA-approved option to treat patients 4-17, which is with an oral powder that’s used to expose patients to small bits of peanut protein that changes their immune response and protects them from those accidental exposures. That’s a new option called oral immunotherapy or OIT, that is increasingly used in clinical practice for older children.
Can you ever overcome the actual allergy itself or is it always with you?
VICKERY: Whether or not children outgrow allergies spontaneously, depends usually on the food itself, to the thing to which they are allergic. Some foods are much more commonly outgrown, like milk, egg, wheat, and soy allergy is very common in early life, but most of those kids are going to ultimately naturally outgrow those allergies and they’re going to go away. On the other hand, some foods like peanuts, tree nuts, cashew, walnut, and so on, and seafood like fish and shrimp, those allergies tend to persist throughout life.
Now there’s a peanut patch. What exactly is the peanut patch?
VICKERY: I mentioned earlier that there’s a new way to start to actively treat peanut allergies with oral exposure to small doses of peanut allergen, to change immune responsiveness, and to make patients less sensitive. That’s an approach that we are now starting to use in the clinic. The problem with oral immunotherapy is that it has some drawbacks. It’s hard for patients to do. They obviously don’t always like the taste of peanuts and find it difficult to consume. It causes a fair number of allergic reactions, so it’s not a treatment that’s right for everybody. What we’ve been studying are other ways to accomplish a similar objective. That is to expose patients to small bits of what they’re allergic to, to change their immune responses. What’s exciting is that you can actually do this through the skin. Through delivering peanut proteins through a patch that’s worn on the skin 24 hours a day, seven days a week.
How exactly does that work through the skin? I want to hear from you how to absorb through the skin and what happens in the body.
VICKERY: This approach that we’ve recently tested is called epicutaneous immunotherapy or EPIT. Where peanut proteins are coded on the underside of a small patch that’s about the size of a nickel or a coder, and it’s applied to the skin and sticks like a sticker. What happens is the humidity that comes off of the skin, releases the peanut protein off of the patch, it falls onto the skin, and then immune cells in the skin are actually able to pick up the allergenic protein and deliver it to the immune system to give it instructions on how to respond to peanut allergen.
What is the protocol? How long does a child have to wear this?
VICKERY: What was recently studied was the application of this epicutaneous peanut patch in peanut-allergic children aged one to three. They start by wearing the patch for just a short time. Half an hour or an hour. As they tolerate it, they gradually wear it for longer periods of time until they can wear it for 24 hours a day. At that point, they’re wearing a patch all the time. They put on a patch, at about the same time every day, repeating the process each day. They’re constantly exposing the body to small amounts of peanut protein. What was shown in this study is if patients do that for a year time, 52 weeks, their ability to tolerate peanut protein is substantially changed and they are much less sensitive to peanuts compared to those who wore a placebo patch.
This protocol and the question is, what have all the studies proven? Is it indeed working?
VICKERY: What the studies have shown is that number one, it’s a feasible approach that children will wear this patch, that it’s quite safe from a systemic allergic reaction perspective. There are some redness and itchiness, as you can imagine underneath where the patch goes on, but from an immunotherapy perspective, it seems to be associated with a better safety profile than what we see in oral immunotherapy. It offers a modest level of protection. That is, the immune responsiveness to peanuts changes. Patients seem to be able to tolerate more peanut exposure. Now eventually, it’s not full protection. This is not a cure and this does not reverse the allergy and make it go away completely. It just lessens the sensitivity levels so that the amount of peanut required to cause an accidental exposure would be significantly greater than without the treatment. To put that in real-world terms, on average, a child that’s allergic to peanuts will react to about 100 milligrams or less of peanut protein. That’s about one-third of one peanut kernel. When we say just avoid peanuts and be careful, that’s hard to do because this is the amount of peanut protein that’s in a bite or two of a peanut-containing food. Patients are not only allergic but are usually quite sensitive to small amounts. This treatment can shift it to where it now takes two, or three peanuts worth of protein before they react. That’s a big difference clinically. This is the treatment that would be worn in somebody who is still being careful to avoid all traces of peanuts, but we know that things happen in the kitchen, at the restaurant, or at the daycare despite our best efforts. This change in their sensitivity level keeps them protected when accidents like that occur.
What are the risks? Are there any risks to this treatment?
VICKERY: The risks are mainly related to local irritation and skin inflammation underneath the patch, which can be uncomfortable. Because again, you wear a patch 24 hours a day so you never really get a break. We treat that with topical medications and sometimes even oral allergy medicines like a typical antihistamine type medicine. Some rare patients find it intolerable and need to take the patch off. They can, if it’s particularly itchy that day, they can remove the patch and then replace it the next day. Anaphylaxis, or remorse significant allergic reaction that involves multiple body parts can happen while wearing the patch. It was more common in the active group than in the placebo group in this study, but it’s still a relatively rare side effect. Overall, the safety profile looks really quite favorable.
How much of a game-changer is this for these kids?
VICKERY: There is no treatment that’s FDA approved for kids under four years of age who have a peanut allergy. As I mentioned, there is now one treatment available for kids four to 17, but there’s nothing for kids under four, which was the age group studied in this trial. This is the phase three trial, which is the last set of testing that products have to undergo before they could be considered for approval by the FDA. We now have a positive phase three study of a new treatment for a very common condition for which there are no current alternatives. If this treatment does become approved by the FDA, It would become the first viable option for patients this age to be treated for their peanut allergy in a way that is pretty safe and pretty patient-friendly. A lot of people would consider that really a breakthrough game-changing type of result.
What’s next for this patch?
VICKERY: We don’t know. Now it’s up to the sponsor, or the manufacturer of the drug to file for approval and then for the FDA to consider that application. We don’t know if that’ll happen, or when it will happen, or when the answer will come from the FDA. It’s important to remember that right now this remains experimental. It’s not something that we can use in the clinic just yet. We will be eagerly waiting to find out, if is there an application on file with the FDA and what the FDA thinks about it. Hopefully, they’ll approve it and it will become a reality for patients in the clinic. Then older patients will be testing a new version of this patch. A similar idea, but one that’s designed to be worn by older kids where it’s been engineered to stick a little better on the skin because in the past with older children, this same patch has not stuck very well and tends to fall off, which has limited its effectiveness. The same company has now designed Version 2.0 of this patch, and we’ll be testing it in a new phase three trial for kids aged four to seven starting this summer.
The final question I have for you is, do you think this patch concept could be something that could be applied to other food allergies, the patch concept?
VICKERY: Yes. In fact, it’s being studied. There is a milk patch that has been studied by the same company, as well as potentially an egg program. Theoretically, this could be used to treat multiple allergens over time. The peanut program is the one that’s furthest along now. But we certainly know that while peanut allergy is a big problem, there are many kids who are allergic to other common foods like milk and egg and tree nuts in cashew and Walmart and so on and those patients need solutions too. I think peanut is a proof-of-concept and the first thing to be investigated. But I think you’ll probably see efforts to address those other really common allergies as well.
In final question for you, do we leave anything out that you wanted in?
VICKERY: In general, the statistics suggest that food allergies now affect about eight percent of kids in the US, which is about one and 13, or one or two kids in every single classroom. As we talked about, this has now become a bigger and bigger problem over time, the prevalence of food allergy does seem to be increasing. That’s a really common condition, eight percent of kids. As I say, historically, we have not been able to offer these patients very much in terms of treatment that is starting to change with research. Still, most patients depend on avoidance strategies and because avoidance is hard, food allergies send a child to the emergency room approximately every three minutes in this country. This is a huge problem and one that we’re actively working to develop solutions for.
END OF INTERVIEW
This information is intended for additional research purposes only. It is not to be used as a prescription or advice from Ivanhoe Broadcast News, Inc. or any medical professional interviewed. Ivanhoe Broadcast News, Inc. assumes no responsibility for the depth or accuracy of physician statements. Procedures or medicines apply to different people and medical factors; always consult your physician on medical matters.
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