The benefits of regularly consuming peanut-containing foods early in life to prevent the development of peanut allergy persist even after stopping peanut consumption for one year, new clinical trial findings show.
The trial, called LEAP-On, was supported by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, and conducted by the NIAID-funded Immune Tolerance Network or ITN.
The results were published online March 4 in the New England Journal of Medicine and presented at the annual meeting of the American Academy of Allergy, Asthma and Immunology in Los Angeles.
The LEAP-On study is an extension of the Learning Early About Peanut Allergy (LEAP) study.
The researchers designed the LEAP study based on observations that Israeli children have lower rates of peanut allergy than Jewish children of similar ancestry residing in the UK. Israeli children typically start consuming peanut-containing foods, including this snack made from peanuts and puffed corn, early in life.
LEAP showed that regular peanut consumption begun in infancy and continued until five years of age led to an 81% reduction in development of peanut allergy in infants deemed at high risk because they already had severe eczema, egg allergy or both.
At the end of LEAP, participants who enrolled in LEAP-On were instructed to avoid peanut consumption for one year to help investigators determine whether continuous peanut consumption is required to maintain protection against development of peanut allergy.
After the avoidance period, peanut allergy prevalence was determined, as it was in LEAP, by an oral food challenge.
Only 4.8% of the children who had regularly consumed peanut-containing foods during LEAP were allergic to peanut following the year of peanut avoidance.
In comparison, the prevalence of peanut allergy was 18.6% among those who had avoided peanut throughout LEAP and LEAP-On.
Adherence to peanut avoidance was high overall, as assessed with a questionnaire and confirmed by quantifying peanut protein in dust samples collected from participants’ beds.
Some of the original peanut-consumers occasionally consumed peanut during the year-long avoidance period, but intermittent, low-dose peanut consumption did not result in new cases of peanut allergy.
The investigators are planning longer-term follow-up of the study participants to assess whether the benefits of regular early-life peanut consumption are maintained over many years when followed by consumption of peanut ad lib, or as much and as often as desired.
