Economic evaluation of duloxetine versus serotonin selective reuptake inhibitors and venlafaxine XR in treating major depressive disorder in Scotland

Major depressive disorders (MDD) are responsible for substantial direct and indirect health care costs. Despite the availability of numerous treatments, the need for effective pharmacotherapy remains. Duloxetine is a relatively balanced serotonin norepinephrine reuptake inhibitor (SNRI) with favourable clinical and tolerability profile. The cost-effectiveness of duloxetine versus established SSRIs, venlafaxine XR and mirtazapine was estimated in the UK.A decision analysis simulating clinical management of MDD was developed to estimate health and economic impacts of alternative treatments over one year. Patients on treatment experience remission, response without remission, no response, relapse or discontinue the initial regimen. Model outcomes were total treatment costs and quality-adjusted life years. Resource utilization data were derived from literature and practising UK psychiatrists and GPs. The robustness of findings with respect to modelling assumptions was assessed in extensive sensitivity analyses.With similar efficacy to venlafaxine XR but lower drug costs, duloxetine is less costly and marginally more effective than venlafaxine XR both in the overall MDD population and in a more severe subgroup. Duloxetine has a low cost-effectiveness ratio in primary care against SSRIs and mirtazapine, and was found cost-saving against mirtazapine in more severe patients.Cost-effectiveness results are sensitive to changes in efficacy parameters and resource use data were collected from physician panel.Duloxetine represents an important option in the treatment of MDD in the UK that can be recommended on economic grounds. With similar efficacy and different side-effect profile to venlafaxine XR it represents a valuable choice to MDD patients.