Skip to main content
OpenTrials
Completed

NCT Number: NCT04641130

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

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).

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Allergic Conjunctivitis Conjunctival Diseases Conjunctivitis Conjunctivitis, Allergic Eye Diseases Hypersensitivity Hypersensitivity, Immediate Immune System Diseases

Age range

18 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Alyatec

Strasbourg, Grand Est, 67000, France

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

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

Treatment and study plan

Exposure to birch pollen in EEC

Other

Patients are exposed to airborne birch pollen allergen. The duration of each exposure is 4h maximum.

Primary outcomes

  1. 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.

Secondary outcomes

  1. 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.

  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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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

Sponsors and collaborators

Lead sponsor

Alyatec

Industry

Registry information

Official study 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.

Important dates

Study start
2017
Primary completion
2017
Study completion
2017
First posted
Nov 23, 2020
Registry last updated
Dec 16, 2020

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.