Exploring Pharmacogenetic Difference Using Adverse Event Database: An Example of Clopidogrel and Cardiovascular Events

Background: Poor clopidogrel metabolizers, carrying a cytochrome P450 2C19 loss-of-function allele, are more frequent among East Asians than Caucasians/White. Materials & methods: The Korea adverse event reporting system database and a case/noncase study design were used to examine the disproportionality of cardiovascular events following clopidogrel use. The US FDA's adverse event reporting system database was also analyzed for comparison. Results: In the Korea adverse event reporting system data, the clopidogrel reporting odds ratio for cardiovascular events was 7.34, more than double that of ticagrelor. In the FDA's adverse event reporting system data, the clopidogrel reporting odds ratio was 4.69, lower than that of ticagrelor. Adjustment for covariates did not change the trend. Conclusion: Considering the prevalence of poor clopidogrel metabolizers and the reported cardiovascular events among Koreans, rigorous clinical management is required for clopidogrel users.