Cost-effectiveness of fluoxetine plus pindolol in patients with major depressive disorder: results from a randomized, double-blind clinical trial

Some preliminary studies have suggested that the β-adrenoceptor 5-HT1A antagonist pindolol (PIN) could increase the effect of selective serotonin reuptake inhibitors (SSRIs). We prospectively estimated the cost-effectiveness of fluoxetine and pindolol versus fluoxetine plus placebo, using results from the first double-blind randomized clinical trial comparing both treatments. Efficacy and medical care resource utilization were collected prospectively in a parallel, randomized, double-blind clinical trial conducted in a single centre in Spain. Average cost-effectiveness (cost/% response and cost/% remission) as well as the incremental cost-effectiveness were calculated for both treatments. A ‘bootstrap’ method was used to calculate confidence limits around the incremental cost-effectiveness ratio. A significantly greater percentage of patients (one-tailed P < 0.05) in the fluoxetine FLX + PIN group than in the FLX + PLA group had experienced a therapeutic response (74.5% versus 58.9%) at 6 weeks. Direct medical costs were lower in the FLX + PIN group (mean 2508 pesetas per patient) than in the FLX + PLA group (mean 31870 pesetas per patient). Hospital admissions due to worsening of depressive symptoms were significantly lower (P < 0.05) in the FLX + PIN group (0/55) than in the FLX + PLA group (4/56). The observed differences in average costs and percentage response in the study were - 29362 pesetas (< 0) and 15.6% (> 0), respectively, and the resulting cost-effectiveness ratio was negative. These outcomes indicate that the FLX + PIN option completely dominates FLX + PLA. These results suggest that, over a course of 6 weeks of treatment, the combination of fluoxetine and pindolol incurs lower direct medical costs than treatment with fluoxetine placebo. Despite their limitations, economic assessments in addition to clinical trials allow a ‘dynamic assessment’ on the potential success of the drug, both from a clinical and an economic point of view, allowing decisions on priorities to be made earlier.