Determination of Grass Pollen Allergen Concentration Inducing Rhinoconjunctivitis Symptoms in Subjects Allergic to Grass Pollen in ALYATEC Allergen Exposure Chamber

Alyatec24 enrolled

Overview

The aim of this study is to determine the optimal concentration of grass pollen allergens inducing rhinoconjunctivitis in subjects allergic to grass pollen in ALYATEC allergen exposure chamber. Four concentrations of grass pollen allergen (Phl p 5) are tested during 3-hour exposures: 0, 30, 60 and 90 ng/m3.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

OTHER

Masking

QUADRUPLE

Enrollment

Conditions

Allergic Rhinitis Due to Grass Pollen

Interventions

Grass Pollen Allergen ExposureOTHER

After the screening visit, subjects are randomized into 3 groups presenting a sequence of allergen concentrations with randomly defined concentrations of Ph l p 5 (0, 30, 60 and 90 ng/m3). Each participant undergo four different 3-hour exposure sessions to grass pollen allergen corresponding to the four different allergen concentrations.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 65 Years

Medical Language ↔ Plain English

Main Inclusion Criteria: * Subjects with symptoms of allergic rhinoconjunctivitis to grass pollen without associated asthma, requiring anti-allergic treatment for at least 2 consecutive pollen seasons; * Subjects with positive skin prick tests to grass pollen extracts (Phleum pratense): papule diameter ≥ 5 mm compared to the negative control (NaCl reaction \< 2 mm)); * Subjects with Phl p 5 specific recombinant Immunoglobulin E ≥ 0.70 kIU/L; * Forced expiratory volume in 1 second (FEV1) ≥ 70% of predicted value at screening and before allergenic exposures; * Women of childbearing age must have a negative pregnancy test at screening and before exposure visits; Main Exclusion Criteria: * Specific immunotherapy (SIT) to grass pollen allergens for more than one month in the 3 years preceding the screening visit; * Ongoing specific immunotherapy to another allergen * History of anaphylaxis following exposure to grass pollen or grass SITs; * Asthma * Ear, Nose \& Throat or ocular surgical intervention in the 6 months preceding inclusion;

Locations (1)

ALYATEC

Strasbourg, France

Outcomes

Primary Outcomes

Optimal concentration of grass allergens (Phl p 5 in ng/m3) to induce a positive rhino-conjunctivitis response in subjects allergic to grass pollen during 3 hours of exposure to grass pollen allergens in the ALYATEC Environmental Exposure Chamber (EEC)

The optimal concentration of grass pollen allergens Phl p 5 in ng/m3 will be determined by evaluating the Area Under the Curve (AUC) of the rhino-conjunctivitis TSS (Total Symptoms Score). The value of the TSS varies from 0 (no symptom) to 24 (highest symptoms)

Time frame: 0 to 3 hours

Secondary Outcomes

Time to obtain a rhino-conjunctivitis response during the 3 hours of exposure to grass pollen allergens in the ALYATEC EEC

The exposure time will be determined by the time necessary to obtain the first uncorrected TSS (Total Symptoms Score) score ≥ 12 and corrected ≥ 10. The value of the TSS varies from 0 (no symptom) to 24 (highest symptoms)

Time frame: 0 to 3 hours

Optimal concentration of grass allergens (Phl p 5 in ng/m3) to induce a positive rhinitis response in subjects allergic to grass pollen during 3 hours of exposure to grass allergens in the ALYATEC Environmental Exposure Chamber (EEC)

The optimal concentration of grass pollen allergens Phl p 5 in ng/m3 will be determined by evaluating the Area Under the Curve (AUC) of the rhinitis-related questions of the TSS (nasal congestion, rhinorrhea, nasal itching, sneezing). The value of the rhinitis-related questions of the TSS varies from 0 (no symptom) to 12 (highest symptoms)

Time frame: 0 to 3 hours

Frequency of bronchial response during 3 hours of exposure in the ALYATEC EEC

The frequency of bronchial response will be assessed by determining the number of subjects presenting at least one drop of FEV1 ≥ 20% during the 3 hours of exposure in ALYATEC EEC.

Time frame: 0 to 3 hours

Use of concomitant medications during and after exposures in the EEC ALYATEC

Data from ClinicalTrials.gov

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