Impact of Sodium Zirconium Cyclosilicate Plus Renin–Angiotensin–Aldosterone System Inhibitor Therapy on Short-Term Medical Costs in Hyperkalemia: OPTIMIZE II Real-World Study

Introduction Patients receiving cardiorenal-protective renin–angiotensin–aldosterone system inhibitors (RAASis) are at increased risk of developing hyperkalemia, which is associated with increased medical costs. The aim of this study was to evaluate the impact of adding sodium zirconium cyclosilicate (SZC) therapy on 3-month medical costs in patients who experienced hyperkalemia while receiving RAASi therapy. Methods The retrospective OPTIMIZE II study used medical and pharmacy claims data from IQVIA PharMetrics ® Plus. Patients aged ≥ 18 years who received SZC (≥ 60 day supply over 3 months’ follow-up) and continued RAASi between July 2019 and December 2021 (Continue RAASi + SZC cohort) were 1:1 exact and propensity score matched with patients who discontinued RAASi after hyperkalemia diagnosis and did not receive SZC (Discontinue RAASi + no SZC cohort). The primary outcome was hyperkalemia-related medical costs to payers over 3 months; all-cause medical and pharmacy costs were also analyzed. Results In the Continue RAASi + SZC ( n = 467) versus Discontinue RAASi + no SZC ( n = 467) cohort, there were significant reductions in mean per-patient hyperkalemia-related medical costs (reduction of $2216.07; p = 0.01) and all-cause medical costs (reduction of $6102.43; p < 0.001); mean hyperkalemia-related inpatient medical costs and all-cause inpatient and emergency department medical costs were significantly reduced. The reduction in all-cause medical cost in the Continue RAASi + SZC cohort offset an increase in the mean per-patient all-cause pharmacy cost (increase of $3117.71; p < 0.001). Conclusion RAASi therapy has well-established cardiorenal benefits. In OPTIMIZE II, management of RAASi-induced hyperkalemia with SZC was associated with lower hyperkalemia-related and all-cause medical costs than RAASi discontinuation without SZC, demonstrating medical cost savings with maintaining RAASi therapy with SZC.