Clinical trial NCT03546413: Follow up of LEAP Participants and Their Families
Official title: Follow up of Learning Early About Peanut Allergy (LEAP) Participants and Their Families: LEAP Trio (ITN070AD)
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Peanut Allergy
Keywords: food
peanut
allergy
prevention
Lead sponsor: National Institute of Allergy and Infectious Diseases (NIAID)
Sponsor class: NIH
Collaborators: name: Immune Tolerance Network (ITN)
name: PPD Development, LP
First posted: 2018-06-06
Enrollment: 1868
Sex: ALL
Minimum age (years): 0
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: * Original Learning Early About Peanut (LEAP) allergy study participants (NCT00329784): at high risk for peanut allergy, given the presence of severe eczema, egg allergy, or both
* Siblings of LEAP participants
* Parents of LEAP participants

Brief summary: This prospective, cross-sectional study was designed to improve understanding of how early-life introduction of peanuts may promote the maintenance of tolerance in adolescence and will serve as an additional safety evaluation of the original nutritional intervention.

Detailed description: Background: Food allergies and specifically peanut allergy (PA) are increasingly common conditions and are an important public health concern. Dietary avoidance of peanut in early life has been recommended in many countries. However, there is evidence that the prevalence of PA is decreased in countries where children are fed peanut beginning at an early age.

The LEAP (Learning Early About Peanut allergy) Study (Protocol ITN032AD, NCT00329784) demonstrated that the early consumption of peanut in high-risk infants successfully reduced the prevalence of peanut allergy at five years of age when compared to peanut avoidance. The LEAP-On Study (Protocol ITN049AD, NCT01366846) was a follow-on study to LEAP and demonstrated that children who consumed peanut in the LEAP study remained protected against developing peanut allergy after cessation of peanut consumption for a period of 12 months.

This LEAP Trio cohort study, a 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 peanut consumption is ad libitum (in the amount and frequency chosen by the individual participant).

The three cohorts in LEAP-Trio include:

* LEAP Participants (NCT00329784, NCT01366846)
* their Siblings and
* their Parents

The study began on July 5, 2018, with data collection continuing until August 31, 2022. This allowed for the enrollment of former LEAP participants aged 12 years.:

• The enrollment phase was 217 weeks (4 years, 2 months).

--The LEAP siblings and parents were enrolled concurrently with the LEAP participant.

• Study participation was defined as a single visit (Visit 144 months); however, more than one clinic appointment might have been required to complete all assessments and were required to be completed within 8 weeks of the in-person visit. Due to COVID-19, telephone visits were undertaken when participants were not able to or did not wish to come into the clinic or have a home visit. The visit window did not apply to the telephone visit. Participants who underwent a telephone visit were invited to subsequently undergo an in-person clinic visit or home visit.

Participant assessments included general medical, -dietary, -allergy (including but not limited to oral peanut food challenges for former LEAP participants and their siblings), and mechanistic assessments (involving the collection of biological specimens, a blood draw, skin prick testing, as examples, to explore hypotheses related to potential mechanisms of peanut allergy).

Eligibility criteria: Inclusion Criteria:

Inclusion Criteria - LEAP Participants:

* Participation in LEAP;
* At least 9.5 years of age
* Willingness to participate in at least one study data collection (i.e. questionnaire, skin pricking testing, or blood draw) procedure; and
* Assent by child and informed consent by parent or legal guardian.

Inclusion Criteria - LEAP Siblings:

* Sibling of LEAP participant;
* Willingness to participate in at least one study data collection (i.e. questionnaire, skin pricking testing, or blood draw); and
* Assent by child and informed consent by parent or legal guardian if child is younger than 16; siblings aged 16 and over will provide their own consent.

Inclusion Criteria - LEAP Parents:

* Biological parent of LEAP participant;
* Willingness to participate in at least one study data collection (i.e. questionnaire, skin pricking testing, or blood draw); and
* Informed consent (for participants only returning a Questionnaire, informed consent will be implied).

Exclusion Criteria:

* There are no exclusion criteria for LEAP Participants, LEAP Siblings, LEAP Parents

Primary outcomes:
measure: Percentage of LEAP Participants With Peanut Allergy
timeFrame: Assessments were performed on consented LEAP Participants at the time of the LEAP Participant's Visit 144 (when the LEAP Study (NCT00329784) Participant was approximately 12 years old (age approximately 144 months)).
measure: Percentage of Younger Siblings With Peanut Sensitization
timeFrame: Assessments were performed on consented siblings at the time of the LEAP Participant's Visit 144 (when the LEAP Study (NCT00329784) Participant was approximately 12 years old (age approximately 144 months)).
Secondary outcomes:
measure: Average Weekly Peanut Protein Consumption of LEAP Participants, Younger Siblings, Older Siblings and Parents
timeFrame: Assessments were performed on consented LEAP Participants and family members at the time of the LEAP Participant's Visit 144 (when the LEAP Study (NCT00329784) Participant was approximately 12 years old (age approximately 144 months)).
measure: Peanut Skin Prick Test Wheal Size for LEAP Participants, Younger Siblings, Older Siblings and Parents
timeFrame: Assessments were performed on consented LEAP Participants and family members at the time of the LEAP Participant's Visit 144 (when the LEAP Study (NCT00329784) Participant was approximately 12 years old (age approximately 144 months)).
measure: Peanut Specific-IgE Measurements for the LEAP Participants, Younger Siblings, Older Siblings, and Parents
timeFrame: Assessments were performed on consented LEAP Participants and family members at the time of the LEAP Participant's Visit 144 (when the LEAP Study (NCT00329784) Participant was approximately 12 years old (age approximately 144 months)).
measure: SCORAD Score for the Eczema Severity in LEAP Participants, Younger Siblings and Older Siblings
timeFrame: Assessments were performed on consented LEAP Participants and family members at the time of the LEAP Participant's Visit 144 (when the LEAP Study (NCT00329784) Participant was approximately 12 years old (age approximately 144 months)).
measure: Percentage of LEAP Participants, Younger Siblings, Older Siblings, and Parents With Eczema
timeFrame: Assessments were performed on consented LEAP Participants and family members at the time of the LEAP Participant's Visit 144 (when the LEAP Study (NCT00329784) Participant was approximately 12 years old (age approximately 144 months)).
measure: Percentage of LEAP Participants, Younger Siblings, Older Siblings, and Parents With Asthma
timeFrame: Assessments were performed on consented LEAP Participants and family members at the time of the LEAP Participant's Visit 144 (when the LEAP Study (NCT00329784) Participant was approximately 12 years old (age approximately 144 months)).
measure: Percentage of LEAP Participants, Younger Siblings, Older Siblings, and Parents With Perennial Rhinitis
timeFrame: Assessments were performed on consented LEAP Participants and family members at the time of the LEAP Participant's Visit 144 (when the LEAP Study (NCT00329784) Participant was approximately 12 years old (age approximately 144 months)).
measure: Percentage of LEAP Participants, Younger Siblings, Older Siblings and Parents With Seasonal Rhinitis
timeFrame: Assessments were performed on consented LEAP Participants and family members at the time of the LEAP Participant's Visit 144 (when the LEAP Study (NCT00329784) Participant was approximately 12 years old (age approximately 144 months)).
measure: Percentage of LEAP Younger Siblings, Older Siblings and Parents With Peanut Allergy
timeFrame: Assessments were performed on consented family members at the time of the LEAP Participant's Visit 144 (when the LEAP Study (NCT00329784) Participant was approximately 12 years old (age approximately 144 months)).
measure: Percentage of LEAP Participants, Younger Siblings and Older Siblings With at Least One Peanut-related Adverse Event
timeFrame: Within 30 days after peanut OFC performed on consented LEAP Participants and family members at the time of the LEAP Participant's Visit 144 (when the LEAP Study (NCT00329784) Participant was approximately 12 years old (age approximately 144 months)).
Other outcomes:
Locations:
city: London
country: United Kingdom
facility: Evelina London Children's Hospital
Study officials:
affiliation: Evelina Children's Hospital, Guy's and St. Thomas's NHS Foundation Trust
name: Gideon Lack, MD
role: STUDY_CHAIR
References:
citation: Sever ML, Calatroni A, Roberts G, du Toit G, Bahnson HT, Radulovic S, Larson D, Byron M, Santos AF, Huffaker MF, Wheatley LM, Lack G. Developing a Prediction Model for Determination of Peanut Allergy Status in the Learning Early About Peanut Allergy (LEAP) Studies. J Allergy Clin Immunol Pract. 2023 Jul;11(7):2217-2227.e9. doi: 10.1016/j.jaip.2023.04.032. Epub 2023 May 3.