[efficacy and safety of salmeterol in long-term therapy in patients with chronic obstructive airway diseases]

Abstract

Background: Salmeterol is a long-acting inhaled beta 2-agonist with a bronchodilating effect lasting over 10 to 12 hours.

Methods: A prospective, open, multi-centre study was performed to evaluate the efficacy and safety of inhaled salmeterol (50 micrograms BID) over a mean treatment period of 29 months (range: 4-1145 days) in 634 patients (54% male, age 45 +/- 15 years) with mild to moderate asthma or chronic obstructive pulmonary disease (COPD). Peak expiratory flow rates, rescue use of short acting beta 2-agonists and safety were study objectives. Patients were critically monitored for a possible loss of bronchodilator efficacy of salmeterol during long-term treatment.

Results: During the first month of salmeterol therapy, morning peak flow improved from 384 +/- 104 l/min to 413 +/- 112 l/min (p < 0.001), and use of rescue salbutamol was significantly reduced (21 +/- 21 to 8 +/- 14 puffs/week during daytime and 9 +/- 12 to 4.5 +/- 9 puffs/week during nighttime, p < 0.001 both comparisons). Peak flow improvement and reduction of short-acting beta 2-agonist use was maintained during the whole study period. Frequent adverse events were exacerbations of the underlying airway disease (24%) and infections (12%), while typical pharmacological side-effects like tremor or tachycardia where reported in less than 1% of all patients.

Conclusions: These results confirm the persistent efficacy and favourable safety profile of salmeterol during long-term therapy over more than two years. No clinical signs of a decreasing bronchodilator potency indicating tachyphylaxis were observed. Salmeterol treatment provides a therapeutic option to further improve the management and care of patients with moderate obstructive airway diseases.