COST-EFFECTIVENESS OF SHORTER DURATIONS OF TICAGRELOR-BASED DUAL ANTIPLATELET THERAPY FOLLOWING MYOCARDIAL INFARCTION

Abstract

Real-world persistence with ticagrelor-based dual antiplatelet therapy (DAPT) following an acute coronary syndrome is lower that of other P2Y12-receptor inhibitors. However, it is not known whether higher than expected rates of patient discontinuation of ticagrelor-DAPT warrants specific intervention. We therefore developed a cost-effectiveness decision analytic model to gauge the clinical impact of shorter durations of ticagrelor-DAPT. Decision trees were created to compare 3, 6, 9, and 12 months of ticagrelor-DAPT to a 12-month regimen of generic clopidogrel-DAPT for patients with myocardial infarction. Clinical outcome probabilities at three-month intervals were generated by estimating the lifetables from relevant landmark clinical trials (PLATO and CURE) and using Dirichlet probability distributions for multiple outcomes. Following ticagrelor discontinuation, patients were assumed to persist with aspirin monotherapy. Clinical outcomes considered in the model included cardiovascular death, myocardial infarction, and major bleeding. Stroke outcomes were not considered as there was no difference in this outcome in the trials. Cost data were derived from a combination of the medical literature and the Régie de l’Assurance-Maladie du Québec medication formulary and is expressed in 2018 Canadian dollars ($CAN). Quality of life weights were derived from the literature. We present our initial analysis of cost-effectiveness at one year (TABLE). Using a willingness-to-pay threshold of $50,000 per quality-adjusted life year (QALY), three months of ticagrelor-DAPT was cost-effective compared to 12 months of clopidogrel-DAPT at one year ($43,496/QALY), 57% probability of cost-effectiveness). Longer regimens of ticagrelor-DAPT were not cost-effective at one year, but are anticipated to be more attractive over a lifetime time horizon. Both cost and effectiveness projections are in line with prior cost-effectiveness models of ticagrelor-DAPT for acute coronary syndromes. Sensitivity analyses showed that the cost-effectiveness of ticagrelor-DAPT was sensitive to both the financial and quality of life costs of major bleeding and myocardial infarction. This analysis shows that even just 3 months of ticagrelor-DAPT is likely to be cost-effective compared to 12 months of clopidogrel-DAPT. As such, we conclude that clinicians should continue to preferentially prescribe ticagrelor-DAPT in appropriate patients and that no specific intervention is warranted at a provincial policy level to improve persistence rates with ticagrelor therapy following myocardial infarction.View Large Image Figure ViewerDownload Hi-res image Download (PPT)