LEAP Study Results
The results of the Immune Tolerance Network’s (ITN) “Learning Early About Peanut” (LEAP), discussed on February 23, 2015 at the American Academy of Allergy, Asthma & Immunology Annual Meeting and published in the New England Journal of Medicine, demonstrate that consumption of a peanut-containing snack by infants who are at high-risk for developing peanut allergy prevents the subsequent development of allergy. The LEAP study, designed and conducted by the ITN with additional support from FARE and led by Professor Gideon Lack at King's College London, is the first randomized trial to prevent food allergy in a large cohort of high-risk infants.
Of the children who avoided peanut, 17% developed peanut allergy by the age of 5 years. Remarkably, only 3% of the children who were randomized to eating the peanut snack developed allergy by age 5. Therefore, in high-risk infants, sustained consumption of peanut beginning in the first 11 months of life was highly effective in preventing the development of peanut allergy.
“For decades allergists have been recommending that young infants avoid consuming allergenic foods such as peanut to prevent food allergies,” notes Professor Lack, the lead investigator for the LEAP study. “Our findings suggest that this advice was incorrect and may have contributed to the rise in the peanut and other food allergies.”
Analysis data and figures from the published manuscript are available to the public on the ITN’s clinical research portal, TrialShare.
About the LEAP Study
Peanut allergy is an aberrant response by the body’s immune system to harmless peanut proteins in the diet. The prevalence of peanut allergy has doubled over the past 10 years in the US and other countries that advocate avoidance of peanuts during pregnancy, lactation, and infancy. The LEAP study was based on a hypothesis that regular eating of peanut-containing products, when started during infancy, will elicit a protective immune response instead of an allergic immune reaction.
LEAP (Learning Early About Peanut allergy) was a randomized controlled clinical trial designed and conducted by the Immune Tolerant Network (ITN) to determine the best strategy to prevent peanut allergy in young children. 640 children between 4 and 11 months of age who were identified as high risk for peanut allergy, based on an existing egg allergy and/or severe eczema, were enrolled in the study.
The children were randomly assigned to two groups – avoidance or consumption:
| Study Group | Instructions until the age of 5 |
|---|---|
| Consumption | Consumed a peanut containing snack with three or more meals (equivalent to 6 grams of peanut protein each week) |
| Avoidance | Did not ingest peanut-containing foods |
The proportion of each group that developed peanut allergy by 5 years of age was used to determine which approach - avoidance or consumption - works best for preventing peanut allergy.
All participants received allergy testing, dietary counselling, physical examinations and were asked to provide occasional blood samples for use in examining differences in immune system development in each of the study groups.