Cost-effectiveness of clopidogrel versus aspirin for chronic maintenance therapy after percutaneous coronary intervention: results from the HOST-EXAM Extended study

초록

BACKGROUND The HOST-EXAM Extended (Harmonizing Optimal Strategy for Treatment of coronary artery disease Extended Antiplatelet Monotherapy) study demonstrated long-term (6 years) superior efficacy and safety of clopidogrel monotherapy compared with aspirin monotherapy during the chronic maintenance period after percutaneous coronary intervention (PCI). We evaluate the cost-effectiveness of clopidogrel monotherapy compared to aspirin monotherapy during the chronic maintenance period after PCI. METHODS A Markov model was used for patients in a chronic maintenance period after PCI incorporating primary efficacy and safety results from the HOST-EXAM Extended study. The healthcare costs and quality-adjusted life years (QALYs) for each treatment were derived from the perspectives of the Korean, US, and UK healthcare systems. Healthcare costs were estimated using data and literature from each country, while utilities were derived from the literature for each country. Transition probabilities were primarily derived from the HOST-EXAM Extended study. Deterministic and probabilistic sensitivity analyses were conducted to explore parameter uncertainty. RESULTS From the Korean healthcare system perspective, clopidogrel monotherapy yielded 0.189 additional QALYs than aspirin monotherapy with incremental lifetime healthcare costs of USD 3,156. This led to an incremental cost-effectiveness ratio (ICER) of USD 16,711 per QALY gained. The cost-effectiveness was most sensitive to the risk of cardiovascular death during the follow-up. From the US and UK healthcare system perspectives, clopidogrel monotherapy decreased healthcare costs by USD 4,564 and USD 1,031 per patient compared with aspirin monotherapy while yielding additional QALYs by 0.258 and 0.251, respectively. CONCLUSIONS The results of this study suggest that clopidogrel monotherapy could be a more cost-effective treatment strategy than aspirin monotherapy during the chronic maintenance period after PCI.