Salmeterol. An appraisal of its quality-of-life benefits and potential pharmacoeconomic positioning in asthma.

Salmeterol is a selective beta 2-receptor agonist with a long duration of action that permits twice daily administration. It is effective in the prophylaxis of asthma symptoms, including nocturnal and exercise-induced asthma, and it has shown clinical benefits in both adults and children. Because of its slow onset of action, salmeterol is not intended for relief of acute symptoms. The addition of salmeterol 50 micrograms twice daily to existing asthma therapy has a positive effect on patient quality of life in the short term (up to 3 months), as assessed by the Living With Asthma Questionnaire and Asthma Quality of Life Questionnaire. This improvement in well-being appears to be greater than that associated with salbutamol (albuterol). Furthermore, in patients with asthma symptoms despite inhaled corticosteroid therapy, a reduced dose of corticosteroid plus salmeterol produced a greater improvement in quality of life as assessed by a daily symptom diary (but not by the Living With Asthma Questionnaire), and was more clinically effective than a higher dose of corticosteroid alone. Evaluation of the effects of salmeterol on quality of life compared with other standard therapies, and extension of these results into the long term are required to consolidate these conclusions. Salmeterol 50 micrograms twice daily was associated with an estimated incremental cost of 736 pounds per symptom-free patient in the final week of 7.5 months' therapy, 648 pounds per patient with improved morning (am) peak expiratory flow rate (PEFR) and 1013 pounds per patient with improved evening (pm) PEFR compared with salbutamol (400 micrograms twice daily) in a cost-effectiveness analysis. However, these results should be tested by sensitivity analyses and compared with the incremental costs of other asthma interventions more applicable to recommended clinical practice. The cost effectiveness of salmeterol relative to other asthma therapies, and the effect of salmeterol on patient quality of life in the long term require further investigation. However, when added to existing asthma therapy, salmeterol improves patient quality of life in the short term (up to 3 months). It may also have some beneficial effects on patient well-being when used to provide a steroid-sparing effect.