Safety and Repeatability of Bronchial Challenge With Grass-pollen
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.
|Study Design:||Observational Model: Cohort
Time Perspective: Cross-Sectional
|Official Title:||Repeatability of a Single Concentration and Single-step Bronchial Allergen Challenge With Grass Pollen|
- repeatability of a bolus-dose inhalative allergen challenge with grass pollen [ Time Frame: feb 2007 - aug 2008 ] [ Designated as safety issue: No ]
- kappa-index of concordance: reliability of the three procedures titrated skin prick-test, incremental challenge and bolus challenge with grass pollen. [ Time Frame: feb 2007 - dec 2007 ] [ Designated as safety issue: No ]
|Study Start Date:||February 2007|
|Study Completion Date:||December 2009|
|Primary Completion Date:||September 2008 (Final data collection date for primary outcome measure)|
grass allergy, bronchial challenge
subjects with known allergy against grass-pollen undergo bronchial challenges
Procedure: inhalative grass-pollen provocation
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.
Other Name: Viasys APS, Allergopharma allergen
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.
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.
|Goethe University, Department of Pulmonology|
|Frankfurt, Hessen, Germany, 60590|
|Principal Investigator:||Stefan Zielen, M.D., Ph.D||Goethe University, Department of Pulmonology|