Clinical Validation Study in Allergic Conjunctivitis to Birch Pollen During Allergen Challenge in ALYATEC EEC

Alyatec

Status: Completed

Conditions: Allergic Conjunctivitis

Treatments: Other: Exposure to birch pollen in EEC

Study type: Interventional

Funder types: Industry

Identifiers

NCT04641130

ALY-002B

Details and patient eligibility

About

This is a single center open study designed to determine the concentration of airborne birch pollen inducing an allergic conjunctivitis response in individuals allergic to birch pollen, during allergen exposures in the Alyatec environmental exposure chamber (EEC).

Enrollment: 16 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
• Subjects with birch pollen rhinitis and conjunctivitis with:
• A history of rhinoconjunctivitis for at least the last 2 consecutive pollen seasons.
• A positive skin prick-test to birch (wheal diameter >6 mm compared to the negative control),
• Specific immunoglobulin E (IgE) for birch> 0.1 kIU/l
• Women of childbearing potential must have a negative pregnancy test during the entire study period with an effective means of contraception: oral contraceptives, intrauterine device, condom with spermicide for at least one month before inclusion in the study and for the duration of the study. At each study visit and each exposure on D1, a urine pregnancy test will be performed.
• A positive conjunctival provocation test to birch during the screening visit at a dilution of 100IR/ml maximum

Exclusion criteria

• Known asthmatic subjects allergic to birch pollen
• 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
• Desensitization to birch pollen in the last 5 years
• Uncontrolled chronic pathologies (hypertension, cardiac, respiratory, renal pathology).
• Active autoimmune disease
• Uncontrolled systemic hypertension
• Subjects who participated in another clinical study in the three months prior to inclusion
• Pregnancy and breast feeding
• Inability to understand and act upon the information provided

Trial design

Primary purpose: Other

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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16 participants in 1 patient group

Exposure to birch pollen

Experimental group

Description:

Step 1: dose validation 16 subjects are exposed for 2 consecutive days (D1 + D2), to the same aerial concentration of Bet v1. The main objective is achieved if the Abelson score is ≥ 5 on J1 or J2. If the main objective is achieved for the 60 ng/m3 concentration, 8 responder subjects will directly perform step 2. If the main objective is not achieved for the 60 ng/m3 concentration, the subjects will be exposed between 7 to 10 days after exposure 1, to an allergen concentration of 120 ng/m3 (Exposure 2: D1 + D2). Step 2: reproducibility Once the allergen concentration has been determined (step 1), 8 of the responder subjects from step 1 are exposed again to this same concentration, during 2 additional exposures (Exposure 3: D1 + D2 and Exposure 4: D1 + D2), at least 7 days apart. A wash-out period of at least 7 days is observed between step 1 and 2. The duration of allergen exposure will be a maximum of 4 hours for all exposures.

Treatment:

Other: Exposure to birch pollen in EEC