The 24 h duration of bronchodilator action of the budesonide/formoterol combination inhaler.
BACKGROUND
The duration of bronchodilator action of the long-acting beta-agonist formoterol when administered in the evening has not been investigated. In this study we have investigated whether a single evening dose of formoterol, administered from the combination budesonide/formoterol (BUD/F) Turbuhaler significantly attenuates the circadian rhythm in airway tone over 24 h.


METHODS
Twenty subjects with mild to moderate asthma (mean FEV1 84% predicted) participated in a double-blind, placebo-controlled, cross-over study. Subjects inhaled, in random order, placebo or BUD/F (2x100/6 microg) administered in the evening (2000 h) on two separate occasions. Lung function measurements including FEV1, specific airways conductance (sGaw) and maximum expiratory flow at 25-75% of vital capacity (MEF(25-75%)) were assessed at baseline, at 1 h and subsequently every 4 h post-dose for 24 h.


RESULTS
Compared with placebo, BUD/F significantly improved the three measures of airways function throughout the 24 h period, with a difference in FEV1 at 24 h of 0.20L (0.04-0.35L). BUD/F attenuated the biphasic pattern of the circadian rhythm in airway tone.


CONCLUSIONS
The single evening administration of formoterol from the combination BUD/F inhaler resulted in a duration of bronchodilation of at least 24 h.
Masoli
Matthew
M
Medical Research Institute of New Zealand, P.O. Box 10055, Wellington 6001, New Zealand.
Williams
Mathew
M
Weatherall
Mark
M
Beasley
Richard
R
D000280:Administration, Inhalation; D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D001993:Bronchodilator Agents / Q000008:administration & dosage*; D019819:Budesonide / Q000008:administration & dosage*; D019454:Chronotherapy; D002940:Circadian Rhythm / Q000187:drug effects; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004338:Drug Combinations; D004983:Ethanolamines / Q000008:administration & dosage*; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D000068759:Formoterol Fumarate; D006801:Humans; D008297:Male; D008448:Maximal Expiratory Flow Rate / Q000187:drug effects; D008875:Middle Aged; D016896:Treatment Outcome
D001993:Bronchodilator Agents; D004338:Drug Combinations; D004983:Ethanolamines; D019819:Budesonide; D000068759:Formoterol Fumarate