Safety and Repeatability of Bronchial Challenge With Grass-pollen

Study Overview
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Brief Summary
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The study is meant to establish a one-step challenge with grass-pollen in patients sensitized for grass-pollen. Therefore the investigators compare a multi-step challenge with grass-pollen with an one-step challenge in order to survey the repeatability and safety.

Detailed Description
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Background: Specific provocation with inhaled allergens is an established tool in clinical practice and research, supporting the understanding of pathophysiology of allergic asthma, and analysing the efficacy of new therapies. This study examines the repeatability of a bolus-dose inhalative allergen challenge with grass pollen. Method: Forty grass pollen allergics should undergo an incremental-dose grass pollen challenge to calculate their PD20-dose. This calculated dose will be applicated twice to analyse the repeatability of the bolus dose challenge. Before and twenty-four hours after the provocation, exhaled nitric oxid (FeNO) will be determined as a marker of bronchial inflammation.

Official Title
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Repeatability of a Single Concentration and Single-step Bronchial Allergen Challenge With Grass Pollen

Conditions
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Allergic Asthma

Intervention / Treatment
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* Procedure: inhalative grass-pollen provocation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age >12 <45 years known sensitization for grass-pollen informed consent Exclusion Criteria: age <12 >45 years clinical asthma requiring regular inhalation vital capacity <80% FEV1 < 75% chronic disease conditions or infections pregnancy inhalative or systemic steroid use substance abuse incapability of understanding the study's purpose and performance

Ages Eligible for Study
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Minimum Age: 12 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| grass allergy, bronchial challenge<br>subjects with known allergy against grass-pollen undergo bronchial challenges | Procedure: inhalative grass-pollen provocation<br>* Subjects undergo allergen challenges with incremental doses of grass pollen allergen. In subjects, who develop a fall in FEV1 of more than 20%, this will be followed by two single-step challenges.<br>* Other names: Viasys APS, Allergopharma allergen;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| repeatability of a bolus-dose inhalative allergen challenge with grass pollen |  | feb 2007 - aug 2008 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| kappa-index of concordance: reliability of the three procedures titrated skin prick-test, incremental challenge and bolus challenge with grass pollen. |  | feb 2007 - dec 2007 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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PD20 FEV1, grass pollen, one-step