Comparative lung bioavailability of fluticasone/salmeterol via a breath-actuated spacer and conventional plastic spacers.

Author(s): Nair A, McKinlay L, Williamson P, Short P, Burns P, Lipworth BJ

Affiliation(s): Asthma & Allergy Research Group, Division of Medical Sciences, Ninewells Hospital & Medical School, University of Dundee, Dundee, Scotland. a.nair@dundee.ac.uk

Publication date & source: 2011-04, Eur J Clin Pharmacol., 67(4):355-63. Epub 2011 Jan 15.

Publication type: Randomized Controlled Trial; Research Support, Non-U.S. Gov't

PURPOSE: This study compares the in vivo relative lung bioavailability of Hydrofluoroalkane (HFA) Seretide delivered via unprimed and unwashed Aerochamber Plus (AP) or Volumatic (VM) spacers, a integrated breath-actuated vortex Synchro-Breathe (SB) device and an Evohaler pMDI (EH) device using adrenal suppression and early fall in serum potassium (K) as surrogates for respirable dose. METHODS: Seventeen healthy volunteers completed this randomised double-blind, double-dummy crossover study. Single doses of placebo/Seretide 250 (total dose ex valve fluticasone 2000 mcg/salmeterol 200 mcg) were administered via the devices. Overnight urinary cortisol/creatinine (OUCC) and serum K were measured at baseline and after each dose. RESULTS: Significant suppression of OUCC and K occurred from baseline with the SB, AP and VM but not with the EH devices. The geometric mean fold suppression (95% confidence interval, p) was: EH, 1.59 (0.80-3.14, p=0.40); AP, 4.26 (3.01-6.02, p<0.001); VM, 3.11 (1.99-4.78, p<0. 001); SB, 3.29 (2.04-5.24, p<0.001). For K, the arithmetic mean fall (mmol/l) (95% confidence interval; p) was: EH, -0.10 (-0.25-0.05, p=0.18); AP, -0.23 (-0.41 to -0.04, p=0.02); VM, -0.22 (-0.44 to -0.01, p=0.04); SB, -0.28 (-0.42 to -0.13, p=0.001). CONCLUSIONS: The breath-actuated SB device was comparable to 'out of the box' small and large volume spacers and produced similar improvements in relative systemic lung bioavailability for fluticasone and salmeterol.