Cost-effectiveness of genotype-guided acenocoumarol therapy in atrial fibrillation: a pharmacogenomic simulation study in the chilean population

Cardiovascular diseases are the leading cause of death in Chile and worldwide, representing a major public health challenge that demands urgent preventive and therapeutic strategies. In atrial fibrillation, anticoagulation is essential, and in Chile acenocoumarol rather than warfarin, used in most countries, is the standard agent. Its dosing shows substantial interindividual variability due to CYP2C9 and VKORC1 polymorphisms. We developed a cohort-based Markov model to compare standard care, genotype-guided dosing, and genotype-guided dosing adjusted for population-level adherence in 123 Chilean patients with atrial fibrillation and 123 matched simulated individuals. Outcomes were measured as quality-adjusted life years (QALYs) and direct medical costs, with cost-effectiveness assessed at a willingness-to-pay (WTP) threshold of US$17,093, estimated using the international approach of approximating the country's GDP per capita rather than a Chilean policy-based value. Genotype-guided dosing achieved the highest effectiveness (2938.34 QALYs) with an incremental cost-effectiveness ratio of US$436.86/QALY versus standard care, remaining cost-effective in sensitivity analyses up to test prices far exceeding the current US$190. The adherence-adjusted strategy was weakly dominated. These results strongly support implementing pharmacogenetic testing for acenocoumarol dosing to optimize anticoagulation safety, efficacy, and cost-effectiveness in Chile.