Cost-effectiveness in unstable economies: the case of sacubitril/valsartan in heart failure with reduced ejection fraction in Argentina

Background Sacubitril/valsartan (an Angiotensin receptor-neprilysin inhibitor—ARNI) is one of the cornerstones in the management of patients with heart failure with reduced ejection fraction (HFrEF) having demonstrated significant reductions in both mortality and hospitalisations as compared with enalapril. It proved to be a cost-effective treatment in many countries with stable economies. In Argentina, a country with chronic financial instability and a fragmented health care system, the estimation of its cost-effectiveness requires to consider local financial data. Objectives To estimate the cost-effectiveness of sacubitril/valsartan in HFrEF in Argentina. Methods We populated an Excel-based cost-effectiveness model, previously validated, using inputs from the pivotal phase-3 PARADIGM-HF trial and from local sources. As the main problem to consider was the financial instability, we adopted a differential approach to cost discounting based on the opportunity cost of capital. Thus, a discount rate for costs were set at 31.6%, using the BADLAR rate published by the Central Bank of Argentina. Discount for effects were set at 5% as is the current practice. Costs were expressed in Argentinian pesos (ARS). We used the perspective for both the social security and private payers at a 30-year horizon. The primary analysis was the incremental cost-effectiveness ratio (ICER) versus enalapril, the previous standard of care. Alternative scenarios performed included a 5% cost discount rate and 3 a 5-year horizon (as is usually used). Results In Argentina the cost-per quality adjusted life-year (QALY) gained for sacubitril/valsartan versus enalapril was 391,158 ARS and 376,665 ARS for a social security and a private payer, respectively, at a 30- year horizon. These ICERs were under the cost- effectiveness threshold of 520,405.79 ARS (1 Gross domestic product (GDP) per capita) suggested by Argentinian health technology assessment bodies. Probabilistic sensitivity analysis showed an acceptability of sacubitril/valsartan as a cost-effective alternative of 86.40% and 88.25% for social security and private payers, respectively. Conclusion Sacubitril/valsartan is a cost-effective treatment in HFrEF using local inputs that considered the financial instability. For both payers considered the cost per QALY gained are under the cost-effectiveness threshold considered.