Eplerenone

Eplerenone (Inspra™) is a selective aldosterone blocker. When added to standard medical therapy, eplerenone significantly improved morbidity and mortality in patients with left ventricular (LV) systolic dysfunction and clinical evidence of heart failure following acute myocardial infarction (MI), in a well designed, placebo-controlled trial known as EPHESUS (Eplerenone Post-acute myocardial infarction Heart failure Efficacy and SUrvival Study). Although eplerenone was generally well tolerated, it was associated with a higher incidence of hyperkalaemia than placebo.

Cost-effectiveness analyses based on this trial have been performed in the US, The Netherlands, Germany, France and Spain. Direct medical costs were analysed based on prospectively collected resource-use data with local costs applied; modelling was conducted to calculate incremental costs per life-year or QALY gained, with survival curves assumed to remain parallel after treatment ended. Eplerenone was associated with a gain of 0.0304 life-years (≈11 days) compared with placebo during the study period.

Based on these analyses, eplerenone was cost effective compared with placebo in patients with LV systolic dysfunction and heart failure after an MI when added to standard therapy for 16 months. The incremental cost per life-year gained for eplerenone versus placebo (for a range of three different life-expectancy projections) was $US10 402–21 876 in the US (year 2001 costs, except for eplerenone [2004]) [equivalent to €12 274–25 814; mid-2001 exchange rate], €5365–12 795 for The Netherlands (year 2003 costs), €6956–14 628 for Germany, €5432–11 423 for France and €8626–18 141 for Spain (year of costing not reported). The US, Dutch, French and Spanish analyses estimated that >90% of observations for incremental cost per life-year gained were below a threshold of $US50 000 or €50 000.

Incremental costs per QALY gained for eplerenone versus placebo in the US, Dutch, French and Spanish analyses were $US15 330–32 405 (€18 089–38 238), €12 148, €8005–16 922 and €12 713–26 873, respectively.

Clinical and pharmacoeconomic data comparing eplerenone with another active drug, such as spironolactone, in this patient population are not available.

In conclusion, when added to standard therapy in patients with LV systolic dysfunction and heart failure after an acute MI, eplerenone was associated with significant reductions in mortality and morbidity compared with placebo. Despite some inherent limitations, available pharmacoeconomic data from Europe and the US indicate that eplerenone is a cost-effective treatment compared with placebo in terms of incremental cost per life-year gained in this patient population.