Budesonide/formoterol as maintenance and reliever treatment compared to fixed dose combination strategies - a Canadian economic evaluation.

OBJECTIVE To compare the cost-effectiveness of budesonide/formoterol in a single inhaler used as Maintenance and Reliever Therapy (SMART) versus fixed higher-dose budesonide/formoterol plus as-needed terbutaline reliever (FHDBF) or fixed dose fluticasone/salmeterol plus as-needed terbutaline reliever (FDFS) in controlling asthma in adults and adolescents. METHODS An economic evaluation was conducted by applying Canadian costs to the results of a large (N=3,335) international randomized, double-blind, controlled trial in which health resource utilization was prospectively collected. Although no Canadian subjects were enrolled in this clinical trial, it was assumed that the results would apply to Canadian patients. Primary outcome measurements included time to first exacerbation and the number of severe exacerbations. Costs included direct medical costs (physician/emergency room visits, hospitalizations, asthma drug costs) and productivity (absenteeism). The time horizon was six months, which corresponded to the duration of the trial. Prices were obtained from 2006 Canadian sources. Both healthcare and societal perspectives were considered. Deterministic univariate sensitivity analyses were conducted. RESULTS In the clinical trial, SMART was superior to FHDBF and FDFS with respect to total number of severe exacerbations (RR 0.72; 95% CI 0.57, 0.90; p=0.0048; RR 0.61; 95% CI 0.49, 0.76; p<0.001, respectively). Exacerbation rates (reported as events per patient per 6 months) were 0.12 for SMART, 0.16 for FHDBF, and 0.19 for FDFS. All treatments provided similar improvements in lung function, asthma control days and asthma-related quality of life. The mean cost per patient per 6 months was $545 in the SMART arm versus $690 in the FHDBF arm and $842 in the FDFS arm from the healthcare perspective; and $676 for SMART, $838 for FHDBF, and $954 for FDFS from the societal perspective. SMART was dominant (more effective, less expensive) in the base case analysis from both the healthcare and societal perspectives. The results were robust under sensitivity testing. CONCLUSIONS The SMART strategy, which allows budesonide/formoterol to be used as both maintenance and reliever medication, is dominant over the alternate strategies of fixed higher dose budesonide and formoterol plus as-needed terbutaline or fixed dose salmeterol and fluticasone plus as-needed terbutaline.