Clinical trial NCT00507039: Safety and Repeatability of Bronchial Challenge With Grass-pollen
Official title: Repeatability of a Single Concentration and Single-step Bronchial Allergen Challenge With Grass Pollen
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Allergic Asthma
Keywords: PD20 FEV1
grass pollen
one-step
Lead sponsor: Johann Wolfgang Goethe University Hospital
Sponsor class: OTHER
First posted: 2007-07-25
Enrollment: 47
Sex: ALL
Minimum age (years): 12
Maximum age (years): 45
Standard ages: CHILD
ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Subjects undergo allergen challenges with incremental doses of grass pollen allergen. In those subjects, who develop a fall in FEV1 of more than 20%, this is followed by two single-step challenges in an interval of at least seven days.

Brief summary: 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: 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.

Eligibility criteria: 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

Primary outcomes:
measure: repeatability of a bolus-dose inhalative allergen challenge with grass pollen
timeFrame: feb 2007 - aug 2008
Secondary outcomes:
measure: kappa-index of concordance: reliability of the three procedures titrated skin prick-test, incremental challenge and bolus challenge with grass pollen.
timeFrame: feb 2007 - dec 2007
Other outcomes:
Locations:
city: Frankfurt
country: Germany
facility: Goethe University, Department of Pulmonology
state: Hessen
Study officials:
affiliation: Goethe University, Department of Pulmonology
name: Stefan Zielen, M.D., Ph.D
role: PRINCIPAL_INVESTIGATOR
References:
citation: Cockcroft DW, Ruffin RE, Frith PA, Cartier A, Juniper EF, Dolovich J, Hargreave FE. Determinants of allergen-induced asthma: dose of allergen, circulating IgE antibody concentration, and bronchial responsiveness to inhaled histamine. Am Rev Respir Dis. 1979 Nov;120(5):1053-8. doi: 10.1164/arrd.1979.120.5.1053. No abstract available.
citation: Cockcroft DW, Murdock KY, Kirby J, Hargreave F. Prediction of airway responsiveness to allergen from skin sensitivity to allergen and airway responsiveness to histamine. Am Rev Respir Dis. 1987 Jan;135(1):264-7. doi: 10.1164/arrd.1987.135.1.264.