A Bronchoscopy Study to Assess the Effects of Inhaled Corticosteroids on Adult Healthy Volunteers

This is a randomized, single-blind, controlled, single centre bronchoscopy study designed to assess the effects of fluticasone propionate on airway gene expression and cellularity in healthy adult controls without asthma. This study will allow a more accurate assessment of the changes in gene/protein expression and cellularity that drive severe treatment-resistant asthma by allowing for the effects that are due to corticosteroids rather than the disease to be considered. This improved mechanistic understanding is important to identify novel therapeutic targets in severe asthma, and to support the development of novel therapeutics. The primary endpoint is the corticosteroid-inducible gene expression pattern in healthy airways.

Approximately 30 healthy adult subjects (age 18-65) will be randomised in a 2:1 ratio to one of two study groups: i) patients will receive fluticasone propionate 500 mcg b.i.d. via Accuhaler for 4 weeks (n=20), or ii) patients will receive no treatment for 4 weeks (n=10). Bronchoscopy will be performed in all patients at baseline, prior to the start of the treatment period and at the end of week 4. The PI, Genentech and Leicester laboratory support staff will be blinded to treatment allocation. A control arm is included to assess the repeatability of the planned analyses, the stability of the gene expression profiles measured during this study period, and to provide a comparator to the treatment group.

Written informed consent for participation in the study must be obtained before performing any study-specific tests or evaluations. Consent will be obtained at the screening visit. At screening, important co-morbidities will excluded . Patients will also be randomised at this screening visit.

To ensure there are sufficient data for analysis, if a subject withdraws before completion of the study, they will be replaced with another subject.