Active clinical trials for "Peanut Hypersensitivity"

This prospective, cross-sectional study is designed to improve understanding of how early-life introduction of peanuts may promote the development of tolerance at 12 years of age and will serve as an additional safety evaluation of this nutritional intervention.

The recent finding that early introduction of peanut can prevent ~70-90% of peanut allergy is a major step towards prevention of food allergy. However, because that finding was from a clinical trial in a very select population, there are several major questions that must be answered in order to implement these findings into clinical practice without causing more harm than good. These questions include who, if anyone, should be screened prior to early introduction for peanut allergy, how this screening should be done, and what quantity of peanut ingestion is needed to prevent peanut allergy. The goal of this project is to answer these critical questions so that the potential of these recent findings can be realized. To that end, 400 infants at high-risk of peanut allergy will be enrolled. These infants will be given a peanut skin prick test, peanut food challenge and have blood drawn for measurement of peanut IgE, and then will be followed for assessment of peanut consumption and development of peanut allergy until 3 years of age.

An oral tolerance induction (OTI) protocol is conducted at the allergy Unit of Saint Vincent Hospital of Lille (France) in standard care since 2006. This protocol consists in exposing patients to regularly increasing doses of allergen. This protocol induces an increase of the threshold reactive dose (the minimum dose of allergen that triggered a reactive reaction) and a decrease of the quantity of specific immunoglobulin E (sIgE) against peanut proteins. The protocol is ended when the patient reaches a threshold reactive dose of 2942mg of peanut proteins, corresponding to 14 peanuts of middle size, which is the maximum dose of peanut that can be found in standard product in France. The investigators wish to study the evolution of the threshold reactive dose and of the sIgE of patients that have followed the OTI protocol. All the needed data are available in the medical records so the study will be conducted on retrospective data.

Food allergy affects up to 10% of the population. The mainstay of management involves dietary avoidance and provision of rescue medication in the event of an accidental reaction. The Integrated approaches to food allergen and allergy management (iFAAM) collaboration is an EU-funded academic/clinical/industry consortium with the aim to improve allergen risk management including food labelling. Much of this work requires the validation of the minimum 'eliciting dose' for the food-allergic population and how this can be translated into risk management. A number of studies (including iFAAM and the TRACE study - NCT01429896) have assessed the eliciting dose for peanut allergic patients, using food challenges where peanut-allergic individuals are eat incremental doses of peanut under strict medical supervision. In this extension study, peanut-allergic subjects will have undergone (in a cross-over manner) three double-blind, placebo-controlled food challenges to peanut: incremental doses of peanut in a water-continuous matrix; incremental doses of peanut baked into a cookie biscuit; a single dose of peanut in a water-continuous matrix. The differences in eliciting dose, symptom pattern and underlying physiological mechanisms will provide essential data on how the presentation and consumption of peanut affects the amount needed to trigger an allergic reaction, to inform industry and food regulators as to how to best protect the food-allergic population.

Food allergy is a common problem, affecting 5-8% of the population. Peanut allergy causes reduced quality of life due to the perceived high risk of severe reactions. Patients rely on accurate labeling of both loose and pre-packed foods, but these are often ambiguous and unhelpful. There is a common conception that labeling is 'over-cautious'. Peanut-allergic consumers face increasingly restricted food choices in complying with this advice due, in part, to the proliferation of advisory labels such as 'may contain peanuts'. This contributes to the reduces quality of life of affected individuals. For industry to provide more accurate and helpful labeling, certain characteristics of the food-allergic population need to be defined. Firstly, the minimum 'eliciting dose' for the population has been estimated by studying large groups of peanut allergic patients who are challenged with peanut ingestion in increasing amounts. From these, an eliciting dose that provokes a reaction in 10% of the food-allergic population has been estimated at between six and 14mg of peanut protein. Translation of population eliciting doses (ED) into acceptable levels of allergen contamination for the population requires consideration of a 'safety factor'- to account for individual variability in dose threshold and severity. Data suggest such variability depends in part on extrinsic factors (exercise and sleep restriction). Each factor may have a different effect in scale and direction. The investigators are proposing a cross-over trial with 85 peanut-allergic adults who will each undergoing a baseline peanut challenge followed by repeat challenges with extrinsic factors applied, in random order (repeat baseline, +exercise and +sleep restriction). These data will further define ED for the UK population and a safety factor derived from shift in threshold, to inform industry and protect the allergic population.

Many authors propose the strict avoidance of allergenic food as the only treatment for children known to be allergic to certain food. However, it has been observed an increase of the frequency and severity of the allergic accidents in these children in the long term. Other teams have suggested treating these allergies (in particular peanut allergies) by controlled and progressive reintroduction of the allergenic food. A good tolerance and a prevention of allergic reactions consecutive to the ingestion of the same allergenic food were observed. The immunological mechanisms of this type of treatment are not well known. A decrease of specific IgE and an increase of IgG4 have been observed in the case of egg allergies after this kind of treatment. Certain experiments realized in mice models testing the allergenic stimulation challenge showed an increase of lymphocytes T regulators (foxp3+ , CD4+, CD25+), stimulated by dendritic cells, and also an increase of interleukin 10, leading to the modification of the balance between Th1 and Th2.Our hypothesis is that after treating allergies by the reintroduction of the allergenic food, the immunological mechanism of acquisition of tolerance is associated to variations in populations of lymphocytes and in the activation or decrease of pro and anti-inflammatory cytokines. This reaction will be studied in two groups: 1. Children with a confirmed allergy to peanuts or nuts and 2. Children without antecedents of allergy or familiar atopy.

An important gap in the management of peanut allergy is that we do not know the threshold dose, below which most peanut allergic individuals will not react. There is likely a spectrum of reactivity to peanut where some individuals react to trace doses, whereas others are able to tolerate larger doses. The purpose of this study is to determine the minimum threshold dose needed to cause a mild objective reaction when peanuts are consumed by peanut-allergic individuals in a carefully controlled clinical setting. 30 peanut-allergic participants aged 7-65 years will undergo a two-day, double blind placebo controlled food challenge. Participants will be gradually fed increasing amounts of peanut, or placebo, until objective allergic symptoms are observed. Statistical modelling of individual threshold doses will be used to determine a population threshold dose, or a level of peanut to which 90% of the peanut-allergic population will not react. Knowledge of threshold doses at an individual and population level is valuable in that it provides critical information for the management of peanut allergy by individuals, their caregivers and health professionals, as well as knowledge of allergen risks to public health agencies and the food industry.

Food allergies are constantly increasing. Peanut and nut allergies are a major cause of allergic reactions. Diagnosed patients are also at risk, because 27% of the patients that had an allergic reaction have another one in the following year with the same food, despite a real improvement in industrial products labeling. The investigators have observed in the allergy Unit that patients (and/or their family) following an elimination diet, sometimes since several years, use very strict elimination strategies. Those strategies sometimes lead to incapacities to recognize the allergens. Yet, a good identification of the allergen is the key to a successful elimination and the non-identification a known risk factor. Ferdman shown in 2006 that 27% of the patients didn't recognize the allergen there were allergic to. However, this is a US study, and geographical specificities have an impact on food consumption and culture. Food allergology needs to take those two elements into account. For example, in France, a single food can have two names. It is the case of peanut, which can be called "arachide", or more frequently "cacahuète". The goal of the study is to observe patient aptitudes to recognize peanut (and the association between the two names) and other nuts available in France and define by the European law, using a plate with various food samples in seed or in shell. Thus, patients in care at the allergy Unit of Saint Vincent Hospital of Lille (France) and their families were surveyed with a standardized procedure at the beginning of their therapeutic education and their capacity to recognize various nuts, to identify peanut ("cacahuète" or "arachide") and to associate the two words "cacahuète" and "arachide" was assessed. It is a standard procedure in therapeutic education, and the responses have been systematically entered in the medical record. The main objective of this study is to describe peanut or nut allergic patient capacity (adult, children and/or the family) to visually identify the foods there are allergic to. The secondary objective of this study is to describe the capacity of patient that describe themselves as allergic to "arachide" to associate this word to the word "cacahuète".

Peanut allergy is a growing public health problem in developed countries with more and more hospitalizations for anaphylaxis. It has been determined that sensitization to certain peanut proteins such as rAra h 2, is predictive of allergy and could predict the severity of reaction (anaphylaxis) during Oral food challenges (OFC). So far, consensual threshold for cutaneous test and IgE as predictor in the positivity of OFC have not been determined. Identification of reactive doses for OFC and phenotype of patients would help to personalize management of patients subgroups, with an optimal security.

This is an open label expanded access program for male and female patients ≥ 4 years old.