Key Points:
Empagliflozin is cost-effective for the treatment of CKD in patients with an urine albumin-to-creatinine ratio of 30 mg/g or more.
Empagliflozin is not cost-effective for the treatment of CKD in patients with an urine albumin-to-creatinine ratio <30 mg/g.
Background: The Study of Heart and Kidney Protection with Empagliflozin (EMPA-KIDNEY) expanded the CKD population that may benefit from sodium-glucose cotransporter 2 inhibitors in terms of eGFR and urine albumin-to-creatinine ratio. This enables a cost-effectiveness analysis of empagliflozin in subgroups stratified by these two parameters.
Methods: A cost–utility analysis using the Markov model was performed to evaluate the cost-effectiveness of adding empagliflozin to the standard treatment for CKD in Japan over 20 years of observation. Each cohort with the initial eGFR (≥45 but <60 ml/min per 1.73 m2, ≥30 but <45 ml/min per 1.73 m2, or ≥20 but <30 ml/min per 1.73 m2) and urine albumin-to-creatinine ratio (<30 mg/g, ≥30 but <300 mg/g, or ≥300 mg/g) within the defined ranges was analyzed. The changes in eGFR were determined on the basis of the EMPA-KIDNEY study. An incremental cost-effectiveness ratio of <¥5,000,000 (approximately $35,500) per quality-adjusted life-year (QALY) was considered cost-effective. One-way deterministic analyses, probabilistic sensitivity analyses, and scenario analyses were conducted to ensure the robustness of the results.
Results: The addition of empagliflozin to the standard treatment was associated with lower costs and higher QALYs in the macroalbuminuria or microalbuminuria cohorts while the incremental cost-effectiveness ratios in the negative albuminuria cohorts were >¥5,000,000 per QALY, regardless of the initial eGFR. The probabilities of empagliflozin being cost-effective were >84% in the macroalbuminuria or microalbuminuria cohorts but <30% in the negative albuminuria cohorts. Scenario analyses where empagliflozin suppressed the eGFR decline in the negative albuminuria cohorts showed that the drug was cost-effective in CKD stage G3b and G4 cohorts. Empagliflozin was not cost-effective in patients with CKD stage G3a and microalbuminuria with the observation period of 10 years.
Conclusions: In patients meeting the enrollment criteria for the EMPA-KIDNEY trial, the addition of empagliflozin to the standard treatment of CKD was judged as cost-effective for patients with albuminuria but not for those without albuminuria in the Japanese health care system.