Phase 1: Run-in/steroid withdrawal | Phase 2: Steroid trial | ||||||||||
14 day run-in | Steroid withdrawal till LOC or 28 days | Screening for progression to phase 2* | Fluticasone 500 μg bd 28+ days | ||||||||
Visit | 1† | 2 | 3.1 | (3.2) | (3.3) | 3.4 | 4.1 | 4.2 | |||
Clinical assessment | × | ||||||||||
Skin prick testing | × | ||||||||||
Feno | × | × | × | ||||||||
Spirometry | × | × | × | × | × | × | × | ||||
Bronchodilator response | × | × | × | ||||||||
Blood tests including IgE | × | ||||||||||
ACQ, ACT, AQLQ | × | × | × | ||||||||
HS challenge | × | ||||||||||
Sputum induction | × | × | |||||||||
Methacholine challenge | × | ||||||||||
AMP challenge | × | × | |||||||||
Diary | × | × | × |
↵* See text for further details regarding progression through screening visits and criteria for progression to phase 2.
↵† Steroid-naïve subjects progressed immediately from visit 1 to visit 3.1.
ACQ, Asthma Control Questionnaire; ACT, Asthma Control Test; AQLQ, Asthma Quality of Life with Standardised Activities; AMP, adenosine monophosphate; Feno, fraction of exhaled nitric oxide; HS, hypertonic saline; IgE, immunoglobulin E; LOC, loss of control.