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

Alyatec

Status: Completed

Conditions: Allergic Asthma; Allergy; Allergy to Cats

Treatments: Other: Exposure to Placebo; Other: Exposure to dose A and dose B of cat allergen; Other: Exposure to a single dose of cat allergen

Study type: Interventional

Funder types: Industry

Identifiers

NCT04678063

ALY-003

Details and patient eligibility

About

This is a randomized, double blind, cross-over study designed to determine the concentration of airborne cat allergen inducing bronchial response in asthmatic subjects allergic to cat, 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 cat allergen in Alyatec EEC.

Enrollment: 31 patients

Sex: All

Ages: 18 to 65 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Subjects having signed the informed consent
• Subjects affiliated to a social security scheme
• Non-specific bronchial hyperreactivity (HRBNS) assessed by a positive methacholine test
• FEV1 value > 70% of theoretical FEV1 value
• Asthma Control Test (ACT) ≥ 20/25 in 4 weeks prior to EEC exposure
• Women of childbearing potential should have a negative pregnancy test throughout the study period with effective contraception.

Group A:

• Cat allergic asthma (GINA 1, 2) associated with rhinitis and / or conjunctivitis symptoms triggered during an exposure to a cat.
• Positive skin prick-test to cat allergen extract (wheal diameter >3 mm compared to the negative control) Specific immunoglobulin E (IgE) for cat allergen > 0.7 kU/L

Group B:

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

Exclusion criteria

• Uncontrolled asthma, ACT asthma control questionnaire less than 20, in the last 4 weeks
• Uncontrolled asthma 2 weeks after interruption of LABA
• Long-term treatment by LABA, within 2 weeks prior to inclusion
• 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
• Subjects treated with oral corticosteroids in the 4 weeks prior to inclusion in the study
• History of severe acute asthma requiring hospitalization in intensive care or intubation
• Subjects treated with biotherapy in the 4 months prior to inclusion in the study
• Presence of a cat at home, or daily exposure to cat allergens
• Desensitization to cat allergens in the last 6 months
• Active tobacco: plus 10 cigarettes / day or tobacco history plus 10 PA

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Triple Blind

---

31 participants in 2 patient groups

Asthmatic subjects allergic to cat

Experimental group

Description:

Group A will be randomized into 2 subgroups of 10 subjects: group A1 and A2. Both subgroupes will be exposed to placebo on exposure 1 then Subgroup A1 will be exposed to dose A on exposure 2 and dose B on exposure 3. Subgroup A2 will be exposed to dose B on exposure 2 and dose A on exposure 3. Dose A and B correspond to different Allergen concentration in the EEC.

Treatment:

Other: Exposure to Placebo

Other: Exposure to dose A and dose B of cat allergen

Asthmatic allergic subjects not sensitized to cat

Active Comparator group

Description:

Group B will be exposed to placebo at exposure 1, and then at exposure 2, the concentration of cat allergens corresponding to the dose that achieved the main objective (Dose A or B).

Treatment:

Other: Exposure to Placebo

Other: Exposure to a single dose of cat allergen