Treatment of young toddlers with peanut oral immunotherapy (OIT) may be the key to inducing remission of peanut allergy, a clinical trial finds.
Six months after completing OIT, one-fifth of children ages 1 to 3 years old with peanut allergy were able to consume the equivalent of 1.5 tablespoons of peanut butter without reacting. Those children met the threshold for remission set by the researchers conducting the IMPACT study.
This clearly shows the ability to eat peanut safely in treated young children “lasts a long time, even for a small group,” says Dr. Edwin Kim. The allergist led the clinical trial site at the University of North Carolina at Chapel Hill. Food allergy remission through therapy has been an elusive target. So the results in the toddlers achieving remission after two years on OIT are exciting, Kim tells Allergic Living.
The goal with peanut oral immunotherapy to date (in patients over the age of 4) has been desensitization, in which the allergic patient needs to take daily allergen doses to maintain protection against an allergen exposure. But Kim cautions that even with the new study’s finding of actual remission in some younger kids, more research is needed to assess whether there is potential for relapse.
The study’s results, published in The Lancet medical journal, show that a majority of the 96 participants who received peanut protein in a daily dose were desensitized to peanuts immediately after treatment. Those participants were able to tolerate 5 grams of peanut protein (equivalent to 16 to 17 peanuts or 1.5 tablespoons of peanut butter) without reaction at an exit oral food challenge.
These children then were not fed peanut for six months, and a second oral challenge followed this abstinence period. This time, 21 percent of the kids could still tolerate the 5 grams of peanut. They are the kids considered in allergy remission.
OIT and Toddlers’ Immune Advantage
Though a small number of participants were 1-year-olds, the results suggest remission hopes are high for the youngest patients. Seventy-one percent of the 1-year-olds were in the group that experienced remission.
“I’m very hopeful. To me, the ticket is getting in early,” says Kim, who is the pediatric allergy and immunology division chief at UNC Health, and director of the UNC Food Allergy Initiative. “We were hopeful going into the study based on our understanding of the immune system.”
The researchers approached the study theorizing that OIT treatment could be more effective in younger patients. They knew that this is when the immune system is more malleable. “We can change the direction of what their immune system is doing,” Kim says.
Aside from younger age, toddlers with lower peanut IgE antibody levels at the start of the trial also achieved the most promising results. When a child is young and experiences a first allergic reaction, that is when the IgE level tends to be small. Kim explains that this provides a window of opportunity when OIT treatment might be most effective.
The idea of OIT for kids diagnosed with a peanut allergy at a young age can be worrisome for families though. This is especially so, since young toddlers can’t articulate their needs. With the IMPACT trial, coaching and availability of the research team played a big role in helping families through the process.
Kim says the team made sure families understood there are risks. He was not surprised that most participants who were taking peanut flour in this study had mild to moderate reactions. (Twenty-one children got epinephrine for 35 moderate reactions). But he was glad to have protocols to manage the reactions safely. “We showed we could do this, and families can do this safely,” he says.
How the IMPACT Trial Worked
The IMPACT clinical trial was conducted at five U.S. medical centers. It was sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), and the lead investigators are Dr. Wesley Burks (UNC Health) and Dr. Stacie Jones (University of Arkansas).
Participants: 146 enrolled, ages 1 to 3 years, with a history of peanut allergy. To qualify for the OIT study, toddlers had to be reactive to half a gram or peanut protein or less. Participants were divided into two groups: 96 kids were assigned to take flour containing peanut protein, while another 50 kids were placed on a placebo flour. In this double-blind study, families and researchers did not know which group a child was in.
Study: Children ate gradually increasing doses each day for 30 weeks up to 2 grams of peanut protein (equivalent to about 8 peanuts). They had a daily dose of peanut or placebo mixed into food for two years, ending with an oral challenge of up to 5 grams of peanut protein. Then, participants avoided peanuts for six months. They returned for another oral challenge of up to 5 grams of peanut protein.
At the end of the treatment period, 71 percent of the toddlers who were eating peanut were desensitized (compared to 2 percent in the placebo group). After the six-month period of peanut avoidance, 21 percent on treatment could still eat 5 grams of peanut without reacting. They were considered in remission.
“Even with a super high bar, we’re getting more than 70 percent,” Kim says, noting the significant amount of peanut in the oral challenge.
The trial investigators are working to find out where the study participants are now, since the study ended in 2018. They are asking participants how much peanut they are eating, along with whether they have had side effects.
“We are hopeful about the results for treatment in younger kids,” Kim says.