Peanut sublingual immunotherapy (SLIT) was associated with significant desensitization in toddlers, ages 1 to 4 years, with no safety issues, a randomized trial showed.
During the placebo-controlled trial, cumulative tolerated dose in the peanut SLIT group increased to 4,333 mg of peanut protein versus 143 mg in the placebo group (P<0.0001), according to Edwin Kim, MD, of the University of North Carolina Food Allergy Initiative in Chapel Hill.
The treatment effect achieved with peanut SLIT was stronger than that previously reported in studies involving older children and it tended to last longer, Kim said during his presentation at the American Academy of Allergy, Asthma & Immunology virtual meeting.
The study is among the first to examine peanut SLIT safety and efficacy in toddlers, and Kim told Ƶ that as more children are introduced to allergic foods during infancy, very early identification of food sensitization will become more common.
"If we can capture these kids at 7 or 8 months of age, we may have more success desensitizing them," he said.
Kim noted that peanut SLIT has been shown to be associated with varying degrees of sensitization in earlier, small clinical trials, but those trials involved older children and even teenagers. The strongest desensitization in these previous trials was observed in the youngest children, he added.
Kim's group included 50 children (average age 2.2 years) with food challenge-confirmed peanut sensitivity (positive peanut-specific IgE and skin prick test).
In the peanut SLIT group, 21 children were white and there were no Black children. In the placebo group, 23 children were white and there were two Black children. A total of 84% and 76% of the children had atopic dermatitis and 28% and 24% had asthma, respectively. The groups were similar across gender, peanut skin-prick tolerance, and double-blind peanut challenge.
Participants were randomized 1:1 to receive peanut SLIT at a daily maintenance dosage of 4-mg peanut protein versus placebo for 36 months. Desensitization was assessed through double-blind, placebo-controlled food challenge (DBPCFC) to 4,333 mg of peanut protein. Sustained unresponsiveness, indicating desensitization, was also assessed by DBPCFC 3 months after discontinuing peanut SLIT.
A total of 36 children (19 peanut SLIT; 17 placebo) completed the desensitization DBPCFC.
Kim reported that 14 children in the peanut SLIT group passed the desensitization DBPCFC, and 12 passed the sustained responsiveness DBPCFC versus 0 and 2 toddlers, respectively, in the placebo group.
Peanut skin-prick test decreased from 10 mm to 3.25 mm with peanut SLIT versus 11.5 mm to 12 mm with placebo (P<0.0001).
Out of approximately 20,000 total doses given, symptoms were associated with 1,031 peanut SLIT doses and 629 placebo doses. Oral itch, skin itch, and gastrointestinal symptoms were the most common symptoms, and no children required epinephrine.
Kim noted that peanut specific IgE and skin testing demonstrated immune modulation in parallel with the clinical responses seen in the trial.
"In this younger cohort, there was a higher percentage of patients demonstrating sustained unresponsiveness than previously reported with peanut SLIT, and also for a longer duration -- 3 months in this case compared to 3 to 4 weeks in previous trials," he said.
SLIT therapy is administered using a dropper, and the treatment is placed under the tongue. It is intended to be held there for 2 minutes before swallowing.
Kim acknowledged that full compliance with the 2-minute recommendation probably did not occur with the study cohort.
"There are tricks of the trade parents learn, like singing songs," he said. "We do our best to train [the children], but it's not likely we are getting full compliance with the 2 minutes in all the young children."
He added that it's possible a portion of the sublingual drops linger in the mouth even after children swallow. "We had concerns, so to see the results we saw despite them was very, very exciting to us," Kim said.
Disclosures
The study was supported by Food Allergy Research and Education (FARE). Database management was provided by the Advance Research Association.
Primary Source
American Academy of Allergy, Asthma & Immunology
Kim E, et al "Safety and efficacy of peanut sublingual immunotherapy in toddler-aged peanut-allergic children" AAAAI 2021; Abstract L2.