Skip to main content
OpenTrials
Completed

NCT Number: NCT03505489

The Effect of Deep Inhalation on Mannitol Responsiveness

The study will assess how the inhalation technique used (deep inhalations versus tidal breathing) influences the results of a mannitol challenge test and a methacholine challenge test, if at all.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Asthma Bronchial Diseases Hypersensitivity Hypersensitivity, Immediate Immune System Diseases Lung Diseases Lung Diseases, Obstructive Respiratory Hypersensitivity Respiratory Tract Diseases

Age range

18 year–75 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 3

Primary location

Asthma Research Lab - University of Saskatchewan

Saskatoon, Saskatchewan, S7N 0W8, Canada

About this study

This study will look at airway responsiveness to inhaled methacholine and mannitol administered with and without deep inhalation. This study will also investigate the role of airway inflammation on these responses, using sputum differential cell counts and fractional exhaled nitric oxide.

This is a single center, open label, randomized study. Individuals with stable asthma will be eligible for enrollment. The study will consist of two parts, screening and testing.

Part 1: Screening

Participants will undergo consent procedures and assessments of fractional exhaled nitric oxide levels, airway responsiveness to methacholine and sputum induction. If participants show airway responsiveness to methacholine (i.e. methacholine PC20 16mg/mL), they will be scheduled to undergo the testing part of the study.

Part 2: Testing

Participants will be randomized to undergo two methacholine or two mannitol challenges. Further randomization will occur with respect to whether the standard challenge method or the modified challenge method is performed first.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • signed informed consent
  • men and women between 18 and 75 years of age
  • FEV1 at first measurement of greater than or equal to 65% predicted
  • methacholine provocative concentration causing a 20% in FEV1 at screening that is less than or equal to 16mg/ml
  • generally good health
  • stable asthma

Exclusion criteria

  • respiratory infection within 4 weeks of screening visit
  • worsening of asthma within 4 weeks of screening visit
  • lung disease other than asthma
  • significant medical comorbidity
  • current smoker or ex-smoker with significant smoking history
  • currently pregnant or breastfeeding

Treatment and study plan

Deep inhalation technique

Procedure

Use of deep inhalations for administration of inhalant

Tidal breathing technique

Procedure

Use of tidal breathing for administration of inhalant

methacholine

Drug

Methacholine direct bronchoconstrictor used for bronchoprovocation challenge

Other names: Provocholine

Mannitol

Drug

Mannitol indirect bronchoconstrictor used for bronchoprovocation challenge

Other names: Aridol

Primary outcomes

  1. Effect of deep inhalation (versus tidal breathing) on mannitol provocative dose causing a 15% fall in forced expiratory volume in one second (FEV1)

    Time frame: 24 hours between mannitol challenges

    Shift in mannitol provocative dose causing a 15% fall in forced expiratory volume

Secondary outcomes

  1. Effect of airway inflammation on methacholine and mannitol challenge results-fractional exhaled nitric oxide

    Time frame: up to 2 weeks, from baseline to end of study

    Collection of fractional exhaled nitric oxide at screening - analysis of resulting measurement indicative of degree of baseline airway inflammation

  2. Effect of airway inflammation on methacholine and mannitol challenge results-sputum

    Time frame: up to 2 weeks, from baseline to end of study

    Collection of sputum at screening - analysis for differential cell counts indicative of degree of baseline airway inflammation

  3. Effect of deep inhalation (versus tidal breathing) on methacholine provocative

    Time frame: 24 hours between methacholine challenges

    Shift in methacholine provocative dose causing a 20% fall in forced expiratory volume

Sponsors and collaborators

Lead sponsor

University of Saskatchewan

Other

Registry information

Important dates

Study start
2018
Primary completion
2019
Study completion
2019
First posted
Apr 23, 2018
Registry last updated
May 15, 2019

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.