Clinical Trial Details
— Status: Enrolling by invitation
Administrative data
| NCT number |
NCT02497261 |
| Other study ID # |
B2015:052 |
| Secondary ID |
|
| Status |
Enrolling by invitation |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
July 2015 |
| Est. completion date |
December 2024 |
Study information
| Verified date |
March 2024 |
| Source |
University of Manitoba |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational
|
Clinical Trial Summary
The purpose of this study is to determine if avoidance of peanut by children with positive
allergy testing to peanut in the first 5 years of life increases the likelihood of developing
a persistent peanut allergy by age 5 years. To answer this question, the investigators need
to determine which children with positive allergy testing to peanut have reactions after
eating peanut (allergic to peanut) and which are able to tolerate eating peanut (not
allergic).
The investigators plan to conduct double-blind placebo-controlled peanut challenges (gold
standard for peanut allergy diagnosis) for CHILD study (http://www.canadianchildstudy.ca)
participants who had positive skin prick testing to peanut at ages 1, 3 or 5 years (in other
words, children who are sensitized to peanut, but may or may not be allergic to peanut) and
who are avoiding peanut without ever having had a reaction or whose history suggests that
they may have outgrown a known peanut allergy. These challenges will not change a child's
ability to tolerate peanut, but will determine if children who are avoiding peanut are
allergic to peanut (and need to continue avoiding peanut) or clinically tolerant to peanut
(and may continue to eat peanut after passing the challenge).
Description:
Introduction:
Food allergy has reached epidemic levels in Canada and peanut allergy is the most prevalent
and one of the more persistent food allergies among Canadian children and adults. Avoidance
or later introduction of peanut has been proposed as a possible cause of the increased rates
of peanut sensitization and allergy. Although delaying the introduction of peanut into
children's diets is no longer recommended, many parents continue to worry about introducing
peanut and some will not introduce peanut into their child's diet without a negative skin
prick test to peanut. However, some children who have never had a reaction to peanut can eat
and tolerate peanut despite being sensitized (having a positive skin prick test) to peanut.
The purpose of this study is to determine if avoidance of peanut by children with positive
skin prick testing to peanut in the first 5 years of life increases the likelihood of
developing a persistent peanut allergy by age 5 years. To answer this question, the
investigators need to determine which children with positive skin prick testing to peanut
have reactions after eating peanut (allergic to peanut) and which are able to tolerate eating
peanut (not allergic).
Specific Objectives:
1. To conduct double-blind placebo-controlled peanut challenges among 5-year-old children
who are sensitized to and avoiding peanut, to determine if they are allergic to peanut
(and need to continue avoiding peanut) or clinically tolerant to peanut (and may
continue to eat peanut after passing the challenge)
2. To determine the relative risk of developing peanut allergy among peanut-sensitized
children who have been eating versus avoiding peanut.
Challenge Procedure:
Double-blind placebo-controlled food challenges are the gold standard clinical practice for
diagnosis of food allergies, and involve the child undergoing separate challenges to the food
and to a placebo so that the child, parents, and physicians and nurses administering the
challenge are masked regarding which challenge is to the food and which is to the placebo.
All children will undergo challenges to both peanut and placebo, in a randomized order. These
challenges will not change a child's ability to tolerate peanut, but will determine if
children who are avoiding peanut are allergic to peanut (and need to continue avoiding
peanut) or clinically tolerant to peanut (and may continue to eat peanut after passing the
challenge).
The challenges will be conducted in clinical units set up for food challenges, by a research
nurse and a pediatric allergist with expertise and experience in managing food allergies and
oral food challenges. Each child will undergo a challenge to peanut on one day and a
challenge to placebo on another day. The peanut will be concealed in a vehicle, such as a
shake or smoothie. One of the challenges will contain peanut and the concealing vehicle and
the other challenge will contain only the vehicle. The challenge foods will be prepared by a
team member who is not otherwise involved in the challenges. A study worker not involved in
the challenges will also be in charge of randomizing the two challenges to peanut or placebo
and of decoding the challenge food identity after both challenges are completed. The
children, their families, the research nurse and the pediatric allergist will not know
whether the challenge food contains the peanut or the placebo until both challenges have been
completed. This procedure helps to distinguish symptoms that occur due to anxiety (equally
likely to occur in both the peanut and placebo challenges) and those that are a reaction to
peanut (occur only during the peanut challenge).
Children who do not develop any symptoms of anaphylaxis (e.g. hives, swelling, trouble
breathing, vomiting, abdominal pain or changes in their level of consciousness) during the
challenge or the 2-hour observation period after the challenge will have passed the challenge
and will be considered clinically tolerant; they will be encouraged to continue eating peanut
at home at least once per week. Children who develop any of these symptoms during the
challenge containing peanut will be considered allergic, especially if symptoms did not occur
during the challenge containing only the vehicle.
