Pharmacoeconomic Analysis of Sitagliptin/Metformin for the Treatment of Type 2 Diabetes Mellitus: A Cost-Effectiveness Study

Abstract

Objectives

To assess the cost-effectiveness and cost utility of sitagliptin/metformin for the treatment of type 2 diabetes mellitus compared to those of glibenclamide/metformin in a semiprivate hospital and to compare the cost-effectiveness and cost utility of sitagliptin/metformin in a semiprivate hospital to those in the public health system (PHS) of Ecuador in 2019.

Methods

A cost-effectiveness study considering the probability of cardiovascular death as the outcome and quality-adjusted life-year as a measure of utility, estimating direct medical costs in US dollars by a model case from the perspective of the third payer. The results will be presented as an incremental cost-effectiveness ratio. One-way and 2-way sensitivity analyses with tornado diagrams were performed.

Results

Direct medical costs were lower at the hospital than from the PHS in Ecuador. Considering the drugs metformin/sitagliptin, the total cost was $35.69 less in the hospital ($880.38) than from the comparator ($916.07). The highest percentage of direct medical costs corresponded to drugs (between 63.94% and 84.65%). An ICER of –$19 131.61 was obtained at the Hospital Un Canto a la Vida and –$1621.85 at PHS. In addition, the cost per quality-adjusted life-year earned was $611.11. Sensitivity analysis showed that the probability of drug use and the relative risk of cardiovascular death associated with such prescription were parameters that most affected the model.

Conclusions

The combination therapy metformin/sitagliptin compared to metformin/glibenclamide was shown not to be cost-effective in the Hospital Un Canto a la Vida, and highly cost-effective in the PHS.