Validation of Strasbourg Environmental Exposure Chamber ALYATEC in Mite Allergic Subjects With Asthma

Alyatec

Status: Completed

Conditions: Allergy to House Dust; Allergic Asthma; Allergy

Treatments: Other: Exposure to a single concentration of HDM allergen in EEC; Other: Exposure to three concentrations of HDM allergen in EEC; Other: Exposure to placebo in EEC

Study type: Interventional

Funder types: Industry

Identifiers

NCT04663880

ALY-001

Details and patient eligibility

About

This is a randomized, double blind, cross-over study designed to determine the concentration of airborne house dust mite allergen inducing bronchial response in asthmatic subjects allergic to mite, during allergen exposures in the Alyatec environmental exposure chamber (EEC).

The study was also designed to validate the specificity of the asthmatic reaction induced by exposure to airborne house dust mite allergen in Alyatec EEC.

Enrollment: 27 patients

Sex: All

Ages: 18 to 50 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Subjects having signed the informed consent
• Subjects affiliated to a social security scheme
• Positive metacholine test
• FEV1 value > 70% of theoretical FEV1 value
• Asthma Control Test (ACT) ≥ 20/25 in 4 weeks prior to EEC exposure

Group A:

• Mild allergic asthma to HDM (GINA 1 or 2) with associated rhinitis and/or conjunctivitis.
• Positive skin prick-test to Dpt and Df (wheal diameter >5 mm compared to the negative control)
• Specific immunoglobulin E (IgE) for Dpt and Df > 0.7 kU/L

Group B:

• Mild allergic asthma (GINA 1 or 2) not sensitized to HDM with associated rhinitis and/or conjunctivitis.
• Negative skin prick-test and specific IgE for Dpt and Df.
• Positive skin prick-test and specific IgE for another allergen.

Exclusion criteria

• Uncontrolled asthma
• Asthma Control Test (ACT) < 20/25 in 4 weeks prior to EEC exposure
• Use of oral corticosteroids in the 4 weeks preceding inclusion in the study
• Use of biotherapy in the 4 months preceding inclusion in the study
• Existence of a severe obstructive syndrome with FEV1 <70% of the theoretical value
• Obstruction triggered by spirometric evaluations
• Hospitalization for asthma or exacerbation in the last 4 weeks
• History of Acute Severe Asthma requiring hospitalization in intensive care or intubation
• Desensitization to dust mite allergens in the last 5 years
• Sensitization to allergens in the indoor environment (cat allergens or molds) with obvious exposure to these allergens
• Active tobacco: plus 10 cigarettes / day and tobacco history of +10 PA
• Uncontrolled systemic arterial hypertension
• Recent myocardial infarction (<3 months)
• Recent stroke (<3 months)
• Known arterial aneurysm
• Epilepsy under treatment
• Progressive tumor pathology
• Chronic renal pathology
• Hypersensitivity to one of the excipients used
• Subjects who participated in another clinical study in the three months prior to inclusion

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Quadruple Blind

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27 participants in 2 patient groups

Asthmatic subjects allergic to house dust mite

Experimental group

Description:

24 subjects were randomized in a doubleblinded manner into six subgroups. All were exposed first to placebo then in cross over to three different Der p1 concentrations, respectively 15, 25, and 46 ng/m3.

Treatment:

Other: Exposure to placebo in EEC

Other: Exposure to three concentrations of HDM allergen in EEC

Asthmatic subjects not allergic to house dust mite

Active Comparator group

Description:

13 subjects were exposed first to placebo then to Der p1 concentration of 25 ng/m3.

Treatment:

Other: Exposure to placebo in EEC

Other: Exposure to a single concentration of HDM allergen in EEC