Cost-Effectiveness Analysis of Initiating Type 2 Diabetes Therapy with a Sodium–Glucose Cotransporter 2 Inhibitor Versus Conventional Therapy in Japan

Introduction: Many patients with type 2 diabetes mellitus (T2DM) suffer from complications that impose substantial burdens on prognosis and medical costs. Accumulating evidence has demonstrated the clinical benefit of sodium–glucose cotransporter 2 inhibitors (SGLT2i) on cardiovascular and renal complications. However, the health economic impact of SGLT2i remains unclear. The aim of this study was to evaluate the cost-effectiveness of initiating antidiabetic therapy with an SGLT2i using Japanese real-world data. Methods: We constructed a natural history model incorporating heart failure (HF), myocardial infarction, stroke, chronic kidney disease, and end-stage renal disease (ESRD) as complications. The target population comprised patients with T2DM who newly initiated their first oral glucose-lowering drugs. By using a population-based microsimulation, we estimated the 10-year medical costs in Japanese yen (JPY) and outcomes (hospitalization for/development of complications and quality-adjusted life years [QALY]) for patients who initiated antidiabetic therapy with an SGLT2i or conventional therapy. Sensitivity analyses included a probabilistic sensitivity analysis (PSA) with 1,000,000 iterations. Results: In the base-case analysis, the total medical cost per person was JPY 1,638,806 versus JPY 1,825,033 and the QALYs were 8.732 versus 8.513 for the SGLT2i strategy versus the conventional strategy, respectively. Thus, initiating treatment with an SGLT2i was dominant, more effective (QALY gain), and lower cost. When treating 10,000 patients, the SGLT2i strategy would reduce all-cause deaths by 410 (552 vs 962), HF events by 201 (897 vs 1098), and ESRD events by 16 (16 vs 32) versus the conventional strategy. The PSA revealed that the probability of dominance for initiating SGLT2i therapy was 90.5%, demonstrating the robustness of the results. Conclusion: Our results suggest that initiating T2DM treatment with SGLT2i, aimed at managing cardiovascular and renal complications from the early stages of diabetes, can improve the clinical outcome and reduce cost burden of T2DM.