Clinical Validation Study in Allergic Conjunctivitis to Birch Pollen During Allergen Challenge in ALYATEC EEC
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|ClinicalTrials.gov Identifier: NCT04641130|
Recruitment Status : Completed
First Posted : November 23, 2020
Last Update Posted : December 16, 2020
|Condition or disease||Intervention/treatment||Phase|
|Allergic Conjunctivitis||Other: Exposure to birch pollen in EEC||Not Applicable|
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||16 participants|
|Intervention Model:||Single Group Assignment|
|Masking:||None (Open Label)|
|Official Title:||Validation and Reproducibility Study of the ALYATEC Allergen Exposure Chamber by Determining the Concentration of Birch Pollen Allergen Inducing Conjunctivitis in Subjects Allergic to Birch Pollen.|
|Actual Study Start Date :||July 13, 2017|
|Actual Primary Completion Date :||August 30, 2017|
|Actual Study Completion Date :||September 11, 2017|
Experimental: Exposure to birch pollen
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.
Other: Exposure to birch pollen in EEC
Patients are exposed to airborne birch pollen allergen. The duration of each exposure is 4h maximum.
- Determine the concentration of birch pollen allergen (in ng/m3 of Bet v1) necessary to induce a conjunctival response in at least 50% of subjects allergic to birch. [ Time Frame: 4 hours exposure in EEC ]A positive conjunctival response is defined by an Abelson score ≥ 5.
- Evaluate the reproducibility of allergen exposure in the ALYATEC EEC [ Time Frame: 4 hours exposure in EEC ]The reproducibility of the exposure will be assessed by measuring the quantity of birch pollen allergen (ng Bet v1) inducing a conjunctival response during step 2.
- Study the effect of EEC birch pollen exposure on symptoms of rhino-conjunctivitis. [ Time Frame: 4 hours exposure in EEC ]
The effect of the exposure on the rhinoconjunctival response will be assessed by Rhinoconjunctivitis Total Symptom Score (RTSS).
The RTSS is the sum of 6 rhinoconjunctivitis symptom scores: sneezing, rhinorrhea, nasal pruritus, nasal congestion, ocular pruritus and watery eyes.
Each symptom is graded in a 4-point scale as follows: 0: no symptoms, 1: mild symptoms, 2: moderate symptoms, 3: severe symptoms. It ranges from 0 to 18. The lower the score, the better the outcome.
- Study the effect of EEC birch pollen exposure on symptoms of rhinitis [ Time Frame: 4 hours exposure in EEC ]
The effect of the exposure on the rhinitis response will be assessed by rhinitis Visual Analogue Scale (VAS).
The rhinitis VAS is a measurement of patient's subjective evaluation of symptoms severity. Patients will score the severity of their nasal symptoms on a scale, with 0 meaning no symptoms and 10 meaning the worst symptoms.
- Study the effect of EEC birch pollen exposure on symptoms of conjunctivitis. [ Time Frame: 4 hours exposure in EEC ]
The effect of the exposure on the conjunctival response will be assessed by Conjunctivitis Visual Analogue Scale (VAS).
The conjunctivitis VAS is a measurement of patient's subjective evaluation of symptoms severity. Patients will score the severity of their ocular symptoms on a scale, with 0 meaning no symptoms and 10 meaning the worst symptoms.
- Measure the amount of particles carrying the allergens. [ Time Frame: 4 hours exposure in EEC ]The amount of particles carrying the allergen will be measured with counters located in the exposure chamber.
- Measure the aerodynamic diameter of the particles carrying the allergens. [ Time Frame: 4 hours exposure in EEC ]The aerodynamic diameter of the particles carrying the allergen will be measured with counters located in the exposure chamber.
- Evaluate changes in mitochondrial respiration [ Time Frame: 4 hours exposure in EEC ]The changes in mitochondrial respiration will be done by evaluating the modifications of the I to IV complex of the mitochondrial respiratory chain, before and after allergen exposure
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04641130
|Strasbourg, Grand Est, France, 67000|
|Principal Investigator:||Frédéric de Blay, Pr.||Alyatec|