Prolonged Protection of the New Inhaled Corticosteroid Fluticasone Furoate Against AMP Hyperresponsiveness in Patients with Asthma

Introduction: Single-dose inhaled corticosteroids (ICS) induce direct anti-inflammatory effects in asthma thereby improving airway hyperresponsiveness (AHR). A novel enhanced-affinity ICS, fluticasone furoate (FF), demonstrated a prolonged duration of action in vitro. The aim of this study was to evaluate the efficacy and duration of action of a single dose of FF by studying protection against AHR to adenosine 5'-monophosphate (AMP) and effects on exhaled nitric oxide (eNO).

Methods: A randomized, double-blind, placebo-controlled, 6-way crossover study (FFA10026) was performed in 24 patients with allergic asthma (mean age 32.8 years, FEV(1) ≥ 70% predicted and PC(20) AMP ≤ 50 mg/ml). Each subject received a single dose of FF 1000 μg, fluticasone proprionate (FP) 1000 μg, or placebo at 2 (FF only), 14 or 26 h prior to AMP challenge and eNO measurement.

Results: FF significantly improved PC(20) AMP compared to placebo, the difference in doubling concentrations being 2.18 (95% confidence interval: 1.13-3.23), 1.54 (0.48-2.59), and 1.30 (0.26-2.34) at 2, 14 and 26 h. FP improved PC(20) AMP significantly at 14 h compared to placebo, but not at the 26-hour time point, the difference in doubling concentrations being 1.72 (0.70-2.75) and 0.33 (-0.69-1.34). There was no significant effect on eNO after either FF or FP at all time points. FF was well tolerated and there were no serious adverse events.

Conclusion: The new inhaled corticosteroid FF, but not FP, demonstrates prolonged protection up to 26 h against AHR to AMP in asthma patients.