METHODS: Data on allopurinol ADR reports (2000-2018) were extracted from the Malaysian ADR database. We identified RMMs implemented between 2000 and 2018 from the minutes of relevant meetings and the national pharmacovigilance newsletter. We obtained allopurinol utilization data (2004-2018) from the Pharmaceutical Services Programme. To determine the impact of RMMs on ADR reporting, we considered ADR reports received within 1 year of RMM implementation. We used the Pearson χ2 test to examine the relation between the implementation of RMMs and allopurinol ADR reports.
RESULTS: The 16 RMMs for allopurinol-related SCARs implemented in Malaysia involved nine risk communications, four prescriber or patient educational material, and three health system innovations. Allopurinol utilization decreased by 21.5% from 2004 to 2018. ADR reporting rates for all drugs (n = 144 507) and allopurinol (n = 1747) increased. ADR reports involving off-label use decreased by 6% from 2011. SCARs cases remained between 20% and 50%. RMMs implemented showed statistically significant reduction in ADR reports involving off-label use for August 2014 [χ2(1, N = 258) = 5.32, P = .021] and October 2016 [χ2(1, N = 349) = 3.85, P = .0499].
CONCLUSIONS: RMMs to promote the appropriate use of allopurinol and prescriber education have a positive impact. We need further measures to reduce the incidence and severity of allopurinol-induced SCARs, such as patient education and more research into pharmacogenetic screening.
Methods: One hundred and three total pharmacogenetics papers involving the CYP2C9, CYP2C19, and CYP2D6 genes were analyzed for their country of origin, racial, and ethnic categories used, and allele frequency data. Correspondence between the major continental racial categories promulgated by National Institutes of Health (NIH) and those reported by the pharmacogenetics papers was evaluated.
Results: The racial and ethnic categories used in the papers we analyzed were highly heterogeneous. In total, we found 66 different racial and ethnic categories used which fall under the NIH race category "White", 47 different racial and ethnic categories for "Asian", and 62 different categories for "Black". The number of categories used varied widely based on country of origin: Japan used the highest number of different categories for "White" with 17, Malaysia used the highest number for "Asian" with 24, and the US used the highest number for "Black" with 28. Significant variation in allele frequency between different ethnic subgroups was identified within 3 major continental racial categories.
Conclusion: Our analysis showed that racial and ethnic classification is highly inconsistent across different papers as well as between different countries. Evidence-based consensus is necessary for optimal use of self-identified race as well as geographical ancestry in pharmacogenetics. Common taxonomy of geographical ancestry which reflects specifics of particular countries and is accepted by the entire scientific community can facilitate reproducible pharmacogenetic research and clinical implementation of its results.