Trial Outcomes & Findings for Follow up of LEAP Participants and Their Families (NCT NCT03546413)

This longer-term follow-up of the LEAP study participants assessed whether the benefits of regular early-life peanut consumption are maintained over many years when followed by consumption of peanut ad lib, in the amount and at frequency chosen by the individual participant. The LEAP siblings and parents cohorts were also enrolled concurrently with the LEAP participant cohort.

Follow up of LEAP Participants and Their Families

Peanut allergy status at LEAP Trio Visit 144 was determined by peanut challenge where possible. Participants who met criteria for peanut oral allergy syndrome in the absence of primary peanut allergy were not considered peanut allergic. Individuals who reported consuming at least 2 g of peanut protein without reaction on at least one occasion in the last year were considered peanut tolerant. If oral challenge was not possible and participants did not meet the above criteria for tolerance, peanut allergy status was determined by an internally and externally validated novel peanut allergy prediction model using data for peanut wheal size (mm), peanut specific IgE (kU/L), Ara h1 (kU/L), Ara h2 (kU/L) and Ara h3 (kU/L)

Peanut sensitization in the siblings of the LEAP Participants was defined as meeting at least one of the following criteria: Specific-IgE ≥0.35 kU/L or Specific-IgE to individual peanut component Ara h2 ≥0.1 kU/L, or Skin prick test wheal to peanut ≥3mm

At LEAP Trio Visit 144, participants were asked to provide responses to questions about their peanut protein consumption. Responses obtained at LEAP Trio Visit 144 were based on the recollection of peanut consumption during the 4 weeks prior to the LEAP Trio study Visit 144.

Skin prick tests were performed to assess participants for potential peanut allergy, select food allergens, and select aeroallergens

Participants had blood draws to assess specific-IgE measurements to peanut, select food allergens and select aeroallergens

Eczema severity was assessed using a modified Scoring Atopic Dermatitis (SCORAD) assessment. The range of the SCORAD is 0-103. A score of 0 indicates no eczema, scores between 0 and 15 indicate mild eczema, scores between 15 and 40 indicate moderate eczema, and scores greater than 40 indicate severe eczema.

Participants were classified as having eczema using standard methodology. Participants were assessed for eczema using a modified Scoring Atopic Dermatitis System (SCORAD) and using participant report of a history of eczema. The range of the SCORAD is 0-103. A score of 0 indicates no eczema, scores between 0 and 15 indicate mild eczema, scores between 15 and 40 indicate moderate eczema, and scores greater than 40 indicate severe eczema.

Participants were classified as having asthma if they meet at least one of the following definitions: 1. Participant report of cough, wheeze, or shortness of breath that was responsive to therapy with bronchodilators on two or more occasions in the previous 24 months; or required one visit to a physician in the previous 24 months; or occurred during the night, during early morning, or upon exercising in the intervals between exacerbations at any time in the previous 12 months. 2. Participant report of an asthma diagnosis with current use of asthma medications (short-acting beta-agonist or controller) 3. Participant report of transient wheeze on exposure to a suspected allergen with confirmatory allergy tests

Participants were considered to have perennial rhinitis if they demonstrated a sensitization to the aeroallergen and clinical history of rhinoconjunctivitis symptoms experienced when exposed to the relevant allergen. Sensitization to the relevant allergen was defined as: 1. Allergen specific IgE ≥ 0.35 kU/L, or 2. Skin prick test wheal size to allergen ≥ 3 mm.

Participants were considered to have seasonal rhinitis if they demonstrated a sensitization to a seasonal aeroallergen and clinical history of rhinoconjunctivitis symptoms experienced when exposed to the allergen during the relevant season. Sensitization to the relevant allergen was defined as: 1. Allergen specific IgE ≥ 0.35 kU/L, or 2. Skin prick test wheal size to allergen ≥ 3 mm

Peanut allergy status at LEAP Trio Visit 144 was determined by peanut challenge where possible. Participants who met criteria for peanut oral allergy syndrome in the absence of primary peanut allergy were not considered peanut allergic. Individuals who reported consuming at least 2 g of peanut protein without reaction on at least one occasion in the last year were considered peanut tolerant. If oral challenge was not possible and participants did not meet the above criteria for tolerance, peanut allergy status was determined by an internally and externally validated novel peanut allergy prediction model using data for peanut wheal size (mm), peanut specific IgE (kU/L), Ara h1 (kU/L), Ara h2 (kU/L) and Ara h3 (kU/L)

Peanut-related adverse events were reported from reactions experienced during or within 30 days after the LEAP Trio Visit 144 peanut oral food challenge (peanut OFC)