Inhaled salmeterol/fluticasone propionate combination: a review of its use in persistent asthma

The long-acting beta2-agonist salmeterol and the corticosteroid fluticasone propionate are available as a combination inhalation device for the treatment of persistent asthma. Well designed studies in adults, adolescents and children aged > or =4 years, demonstrate that combined salmetero/fluticasone propionate 50/100, 50/250 and 50/500 microg administered via a dry powder inhaler (DPI) is clinically equivalent to concurrent delivery of the same dosages of the 2 drugs via separate DPIs. In adults and adolescents, combined salmeterol/fluticasone 50/100 and 50/250 microg twice daily produced rapid improvements in lung function that were consistently greater than those in patients receiving monotherapy twice daily salmeterol 50 microg, fluticasone propionate 100 or 250 microg or placebo in 2 well designed studies. Recipients of the combination had a significantly greater probability of completing 12 weeks of treatment than patients receiving monotherapy or placebo. The combination also produced significant improvements between baseline and end-point in all secondary outcome variables (morning and evening peak expiratory flow, daytime symptom scores, days and nights without asthma symptoms and requirements for as-needed beta-agonists) and health-related quality of life (QOL). Combination therapy was superior to monotherapy with salmeterol and placebo for all outcomes in both studies, and was superior to fluticasone propionate 100 microg for all but 1 outcome (nights without awakenings) in 1 study. Similar results were obtained in patients who had previously been using short acting beta2-agonists alone. Combined twice daily salmeterolfluticasone propionate 50/100 and 50/250 microg produced greater improvements in lung function than inhaled budesonide at higher dosages than fluticasone propionate in the combination. Combined salmeterol/fluticasone propionate 50/250 microg produced similar improvements in lung function to concurrent budesonide 800 microg plus formoterol 12 microg when given twice daily for 12 weeks. In another 12-week trial, combined salmeterol/fluticasone propionate 50/100 microg was more effective than oral montelukast 10 mg/day plus fluticasone propionate 100 microg twice daily in patients with suboptimally controlled asthma. Salmeterol/fluticasone is more cost effective than monotherapy with fluticasone propionate or budesonide. The most frequent adverse events associated with salmeterol/fluticasone propionate are headache, throat irritation, hoarseness and candidiasis.

Combined salmeterol/fluticasone propionate is as effective as the 2 drugs given concurrently via separate inhalers and significantly more effective than either drug given alone at the same nominal dosage. The combination is also significantly more effective than montelukast plus fluticasone propionate or monotherapy with inhaled budesonide. Furthermore, the combination is more cost effective than inhaled corticosteroid monotherapy.