Safety and Repeatability of Bronchial Challenge With Grass-pollen

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

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT00507039

Enrollment

Registered

2007-07-25

Start date

2007-02-28

Completion date

2009-12-31

Last updated

2011-10-12

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Allergic Asthma

Keywords

PD20 FEV1, grass pollen, one-step

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.

Interventions

PROCEDUREinhalative 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.

Study design

Observational model

COHORT

Time perspective

CROSS_SECTIONAL

Eligibility

Sex/Gender

ALL

Age

12 Years to 45 Years

Healthy volunteers

Yes

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

Design outcomes

Primary

Measure	Time frame
repeatability of a bolus-dose inhalative allergen challenge with grass pollen	feb 2007 - aug 2008

Secondary

Measure	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

Countries

Germany

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026