Cost effectiveness of fluticasone propionate plus salmeterol versus fluticasone propionate plus montelukast in the treatment of persistent asthma

Background: Asthma is a chronic disease, the two main components of which are inflammation and bronchoconstriction. Fluticasone propionate (FP) and salmeterol, a strategy that treats both main components of asthma, has been recently compared with FP plus montelukast in a randomised clinical trial. The present study reports economic evaluation of these two strategies. Objective: To determine the relative cost effectiveness when persistent asthma is treated with FP/salmeterol 100/50 mug twice daily administered via a single Diskus(R) inhaler device versus treatment with FP 100 mug twice daily via a Diskus(R) inhaler plus oral montelukast 10 mg once daily. Study design: A cost-effectiveness analysis was performed by applying cost unit data to resource utilisation data collected prospectively during a US randomised, double-blind, 12-week trial of FP/salmeterol (n=222) versus FP + montelukast (n=225). Patients were greater than or equal to15 years of age and were symptomatic despite inhaled corticosteroid (ICS) therapy. Patients and methods: Efficacy measurements in this analysis included improvement in forced expiratory volume in 1 second (FEV1) and symptom-free days. Direct costs included those related to study drugs, emergency room department visits, unscheduled physician visits, treatment of drug-related adverse events (oral candidiasis), and rescue medication (salbutamol [albuterol]). The study assumed a US third-party payer's perspective with costs in 2001 US dollars. Results: Treatment with FP/salmeterol resulted in a significantly higher proportion (p<0.001) of patients who achieved a ≥12% increase in FEV1 than treatment with FP + montelukast (54% [95% CI 47%, 61%] vs 32% [95% CI 26%, 38%]). Lower daily costs and greater efficacy of FP/salmeterol resulted in a cost-effectiveness ratio of $US6.77 (95% CI $US5.99, $US7.66) per successfully treated patient in the FP/salmeterol group compared with $US14.59 (95% CI $US12.12, $17.77) for FP + montelukast. In addition, FP/salmeterol achieved similar efficacy in terms of symptom-free days compared with FP + montelukast (31% [95% CI 26%, 35%] vs 27% [95% CI 23%, 32%]), but at a significantly lower daily per-patient cost ($US3.64 [95% CI $US3.60, $US3.68] vs $US4.64 [95% CI $US4.56, $US4.73]). Sensitivity analyses demonstrated the stability of the results over a range of assumptions. Conclusion: From a US third-party payer's perspective, these findings suggest that treating the two main components of asthma (inflammation and bronchoconstriction) with FP/salmeterol may not only be a more cost-effective strategy but may actually lead to cost savings compared with the addition of montelukast to low-dose FP in patients with persistent asthma. The results were found to be robust over a range of assumptions.