Economic Evaluation of Patiromer in Patients with Concomitant Heart Failure and Chronic Kidney Disease in Italy

Background Hyperkalaemia (HK), in patients with heart failure (HF) with and without chronic kidney disease (CKD), is potentially life-threatening. Risk of HK is further heightened in those patients receiving renin–angiotensin–aldosterone system inhibitors (RAASi), used to reduce cardiovascular morbidity and mortality in HF. Patiromer, an oral potassium (K+) binder, has been shown to reduce the risk of HK and enable optimal RAASi dosing. We evaluated the cost-effectiveness of patiromer in HF patients with CKD in the Italian setting, utilising results from the recent DIAMOND clinical trial, which assessed long-term use of patiromer in HK management. Methods An established Markov model was adapted to include data from DIAMOND using the National Health Service (NHS) perspective. In DIAMOND, patients received patiromer during a run-in period (up to 12 weeks) to achieve optimal RAASi without HK. However, this led to low mean K+ concentrations in the placebo arm, resulting from a legacy effect of patiromer in the run-in phase of the trial. Therefore, the DIAMOND population was adjusted to a real-world population to better represent the K+ levels in the standard of care (SoC) arm. Mean K+ concentration for baseline and the patiromer arm was calculated from the overall population at baseline (screening phase) and after treatment (end of run-in period), respectively. Lifetime trajectories were estimated for quality-adjusted life years (QALYs), life years (LYs) and costs. Results The economic evaluation model calculated a discounted total average cost per patient of €109,900 for patiromer and €64,847 for SoC. Patiromer generated a gain of 1.97 LYs (1.55 QALYs) compared with SoC. The incremental cost-effectiveness ratio (ICER) for patiromer was €29,060/QALY gained versus SoC. Conclusion Applying DIAMOND data, patiromer is deemed to be cost-effective at a willingness-to pay threshold of €40,000 per QALY gained in Italy.