Rationale: To compare peanut-avoidance and early peanut-consumption as interventions for the prevention of peanut allergy (PA) within a randomised controlled trial.
Methods: This randomised control group study aimed to recruit 640 high-risk infants aged 4-11 months. High risk was defined as severe eczema and/or egg allergy. The 640 participants were to be stratified by peanut skin prick tests (SPT) results into one of two Strata; SPT-Negative Stratum (n=542) or the SPT-Positive Stratum (SPT 1-4mm, n=98). Participants were then randomly assigned to receive early high-dose peanut, or to complete peanut avoidance. The primary endpoint is the prevalence of clinically-defined PA between the two groups at 60 months of age. Secondary endpoints include allergic sensitization to select ingested and inhaled allergens, rhinoconjunctivitis and asthma. Analyses of Cellular and Humoral responses will be performed.
Results: Nine hundred participants were screened of which 640 were eligible for enrolment (98 assigned to the SPT-positive Stratum and 542 to the SPT-Negative Stratum). Demographics at enrolment: age (median 7.8 months, range 4-11), male (60%), ethnicity (Caucasian 74%, Mixed 14%, Black 8%, Asian 4%). 89.1% of participants met the study criteria for Severe Eczema and 65.3% of participants met the study definition of Egg Allergy; 52.0% met both criteria. None of the participants had consumed peanut prior to enrolment.
Conclusions: Enrolment of 640 high-risk infants into the LEAP Study has now successfully completed. It is hoped that the comparison between these two approaches, to be made at 60 months of age, will identify the best strategy for the prevention of peanut allergy.