Steroid Titration Against Mannitol IN Asthma

Study Overview
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Brief Summary
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The investigators hypothesise that titration of asthma medication against mannitol challenge results will reduce the number of mild asthma exacerbations, in one year, when compared with titration against BTS guidelines. To test this hypothesis the investigators propose a primary care, parallel treatment, patient blinded study in which matched groups of asthmatic patients will be treated in accordance either with BTS guidelines or with our treatment algorithm dependent on mannitol challenge result. Purpose of the study is to evaluate the efficacy of a treatment algorithm based on the measurement of airway hyperresponsiveness to mannitol challenge, a surrogate marker of airway inflammation, in the long term treatment of asthma in comparison to BTS guidelines.

Official Title
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Titrating Inhaled Steroid Dose Against Mannitol Hyper-responsiveness or BTS Outcomes: Comparative Effects on Asthma Exacerbations Over 1 Year

Conditions
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Asthma

Intervention / Treatment
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* Other: mannitol (an airway challenge agent)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male or female asthmatics aged >/= 16 years Females must be non pregnant and non lactating FEV1 >/= 50% predicted Mannitol PD10 </= 635 mg at end of step down period No recent exacerbations of asthma requiring oral prednisolone in the previous 3 months Able to perform all the techniques necessary to carry out the challenge testing and lung function and compliant with taking the study medication Good inhaler technique which will be reinforced at each study visit Exclusion Criteria: Male or female patients aged 15 or below FEV1 </= 50% predicted Patients who are currently taking a pulse of oral corticosteroids Patients with the following concomitant illnesses:bronchiectasis, allergic bronchopulmonary aspergillosis, COPD, heart failure, pulmonary fibrosis, rhino-sinusitis with polyps Immunocompromised patients Patients with recurrent LRTI Patients with documented aspirin induced asthma on LRTAs Pregnancy Known or suspected hypersensitivity to ICS or other excipients of the MDIs HIV/Hepatitis B or C positive

Ages Eligible for Study
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Minimum Age: 16 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Reference arm<br>Asthmatic patients managed as per British Thoracic Society guidelines by symptoms and lung function. | Other: mannitol (an airway challenge agent)<br> <br> |
| Active Comparator: Mannitol managed arm<br>Group of asthmatic patients managed according to their mannitol challenge. | Other: mannitol (an airway challenge agent)<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |