A MODEL TO EVALUATE THE COST-EFFECTIVENESS OF ORAL THERAPIES IN THE MANAGEMENT OF PATIENTS WITH MAJOR DEPRESSIVE-DISORDERS

The introduction of a new antidepressant, venlafaxine, a serotonin nor epinephrine reuptake inhibitor (SNRI), has provided researchers with t he opportunity to take a closer look at the issues involved in selecti ng a product for a formulary. To aid decision makers in considering th e adoption of this new therapy, a pharmacoeconomic simulation model wa s developed to evaluate the cost-effectiveness of SNRIs versus traditi onal oral therapies in the management of patients with major depressiv e disorders (MDDs) from a cost-based payer perspective. Four treatment regimens for MDD were compared: tricyclic antidepressants, selective serotonin reuptake inhibitors, heterocyclic antidepressants, and SNRIs . The principles of decision analysis were used to calculate outcome p robabilities based on data from a meta-analysis. The expected cost of each regimen was calculated using cost data from a survey of three hea lth maintenance organizations located in Missouri, Massachusetts, and California. The model suggests that SNRI therapy demonstrates the high est level of cost-effectiveness in an inpatient setting when using bot h brand and generic acquisition costs of the drugs. When comparing tre atment regimens for out-patients, the generic heterocyclic antidepress ants demonstrate the highest level of cost-effectiveness; when using b rand acquisition costs, the SNRIs demonstrate the highest level of cos t-effectiveness. Sensitivity analysis calculated the robustness of the conclusions to all major parameters.