[Onset of action of formoterol in patients with moderate to severe, partially reversible airflow obstruction assessed by bodyplethysmography].
BACKGROUND
Formoterol is a long acting beta2-agonist used for the treatment of obstructive airway diseases. Compared with Salmeterol, Formoterol has a rapid onset of bronchodilation. There are only scant data regarding the comparative onset of action using bodyplethysmography in moderate to severely obstructive patients.


METHODS
In a mono-center, single-blinded parallel group study 60 patients (age: 61.9 +/- 12.8 years, 65 % male) with moderate to severe (mean FEV(1) 40.6 +/- 15.3 % of predicted), partially reversible (FEV(1) post bronchodilator > 15 % from baseline) airway obstruction were treated with either formoterol 12 microg bid or salmeterol 50 microg bid over a period of two weeks. Onset of action was measured by airway resistance (sRaw) before and after two weeks of treatment.


RESULTS
Compared with Salmeterol, Formoterol had a significantly faster onset of action (10 % decrease of Raw) at baseline (F: 1.4 +/- 0.9 vs. S: 15.1 +/- 34.5 min., p < 0.0001) and after two weeks of treatment (F: 6.2 +/- 21.6 vs. S: 51 +/- 135 min., p < 0.0001). Morning FEV(1) improved similarily during treatment in both study groups, when compared with baseline lung function (F: 1.38 +/- 0.64 vs. 1 +/- 0.41 l; S: 1.43 +/- 0.67 vs. 1 +/- 0.4 l, p < 0.05, both comparisons). Both treatments were well tolerated.


CONCLUSIONS
Formoterol produces a rapid improvement of airway resistance in patients with moderate to severe, partially reversible airway obstruction. The onset of bronchodilation was significantly faster for Formoterol compared with Salmeterol. Both drugs improved lung function similarily after two weeks of treatment. It is important to distinguish beta2-agonists not only into short- and long-acting but also into fast- and slow-acting.
Beier
J
J
Schwerpunkt Pneumologie, III. Medizinische Klinik und Poliklinik, Klinikum der Johannes Gutenberg-Universität, Mainz. j.beier@3-med.klinik.uni-mainz.de
Beeh
K M
KM
Tröger
K
K
Stenglein
S
S
Bräutigam
M
M
Buhl
R
R
Schmidt
E W
EW
D001993:Bronchodilator Agents / Q000627:therapeutic use; D004983:Ethanolamines / Q000627:therapeutic use*; D005260:Female; D000068759:Formoterol Fumarate; D006801:Humans; D008297:Male; D008875:Middle Aged; D010993:Plethysmography, Whole Body; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D016037:Single-Blind Method
D001993:Bronchodilator Agents; D004983:Ethanolamines; D000068759:Formoterol Fumarate