Empiric treatment with aspirin and ticagrelor is the most cost-effective strategy in patients with minor stroke or transient ischemic attack.

BACKGROUND: Patients with minor ischemic stroke or transient ischemic attacks (TIAs) are often treated with dual antiplatelet therapy regimens as part of secondary stroke prevention. Clopidogrel, an antiplatelet used in these regimens, is metabolized into its active form by the CYP2C19 enzyme. Patients with loss of function (LOF) mutations in CYP2C19 are at risk for poorer secondary outcomes when prescribed clopidogrel. AIMS: We aimed to determine the cost-effectiveness of three different treatment antiplatelet regimens in ischemic stroke populations with minor strokes or TIAs and how these treatment regimens are influenced by the LOF prevalence in the population. METHODS: Markov models were developed to look at the cost-effectiveness of empiric treatment with aspirin and clopidogrel versus empiric treatment with aspirin and ticagrelor, versus genotype-guided therapy for either 21 or 30 days. Effect ratios were obtained from the literature, and incidence rates and costs were obtained from the national data published by the Singapore Ministry of Health. The primary endpoints were the incremental cost-effectiveness ratios (ICERs). RESULTS: Empiric treatment with aspirin and ticagrelor was the most cost-effective treatment. Genotype-guided therapy was more cost-effective than empiric aspirin and clopidogrel if the LOF was above 48%. Empiric ticagrelor and aspirin was cost saving when compared to genotype-guided therapy. Results in models of dual antiplatelet therapy for 30 days were similar. CONCLUSION: This study suggests that in patients with minor stroke and TIA planned for dual antiplatelet regimens, empiric ticagrelor and aspirin is the most cost-effective treatment regimen. If ticagrelor is not available, genotype-guided therapy is the most cost-effective treatment regimen if the LOF prevalence in the population is more than 48%.

Cost Effectiveness of Genotype-Guided Antiplatelet Therapy in Asian Ischemic Stroke Patients: Ticagrelor as an Alternative to Clopidogrel in Patients with CYP2C19 Loss of Function Mutations.

BACKGROUND: Patients with ischemic stroke are often treated with clopidogrel monotherapy as part of secondary stroke prevention. The prevalence of loss of function (LOF) mutations in the CYP2C19 gene is higher in Asians than in Western populations. Patients with loss of function (LOF) mutations are at risk for poorer secondary outcomes when prescribed clopidogrel. OBJECTIVE: We aimed to determine the cost effectiveness of genotype-guided antiplatelet therapy in an Asian population with the aim of prescribing ticagrelor as an alternative to patients with LOF mutations. METHODS: Markov models were developed to look at the cost effectiveness of genetic testing of CYP2C19, with patients who screened positive for LOF alleles being switched to ticagrelor compared to universal clopidogrel treatment. Effect ratios were obtained from the literature and incidence rates and costs were obtained from the national data published by the Singapore Ministry of Health. Lifetime costs and quality-adjusted life-years (QALYs) were calculated. The primary endpoints were the incremental cost-effectiveness ratios (ICERs). RESULTS: The prevalence of the LOF mutations was 61% in the population, with 65% of ethnic Chinese, 60% of ethnic Indian, and 53% of ethnic Malay patients having LOF mutations. Based on this prevalence, the overall ICER of genetic testing was S$33,839/QALY with ICERS of S$30,755/QALY, S$33,177/QALY, and S$41,470/QALY for Chinese, Indians, and Malays, respectively. CONCLUSION: This study suggests that it is cost effective to screen for LOF mutations in the CYP2C19 gene in ischemic stroke populations, with ticagrelor as a substitute for clopidogrel in those with LOF mutations.