Economic Evaluation of Canagliflozin versus Glimepiride and Sitagliptin in Dual Therapy with Metformin for the Treatment of Type 2 Diabetes in Italy

Abstract

Purpose To assess the treatment costs (direct medical costs) of canagliflozin versus glimepiride or sitagliptin 100 mg in patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin from the perspective of the Italian National Health Service. Methods A cost-minimization analysis (CMA) was conducted to compare the mean annual costs for a patient with T2DM treated with canagliflozin 100 or 300 mg, glimepiride (mean dose of 5.6 mg), or sitagliptin 100 mg. Two models were constructed to compare canagliflozin versus glimepiride and canagliflozin versus sitagliptin. Both models estimated annual patient costs using data from two clinical trials. In both models, only direct medical costs (antidiabetic drugs, concomitant drugs, hospitalizations, hypoglycemic events, glycemic control, genital mycotic infections, and weight) were considered. Italian costs were drawn from the literature and local sources. Uncertainty was assessed by deterministic sensitivity analyses and threshold analyses. Results Canagliflozin 100 and 300 mg were associated with lower expected costs (€2,785.46 and €2,979.52, respectively) versus glimepiride (€3,167.90). In the second comparison, canagliflozin 100 or 300 mg were also associated with lower expected costs (€2,820.05 and €3,013.96, respectively) versus sitagliptin 100 mg (€3,030.38). Sensitivity analyses generally supported the base case findings. Conclusions This CMA showed that treatment with canagliflozin 100 or 300 mg is a cost-saving strategy compared with glimepiride or sitagliptin 100 mg in patients with T2DM inadequately controlled with metformin from the perspective of the Italian National Health Service.