Pharmacogenetics in practice: safe, effective and cost-saving
Within the healthcare sector increasing use is being made of pharmacogenetic information, which means that drugs are being tailored to patients ever more effectively. Recently, Dutch cardiologists demonstrated in an extensive study that this can be a safe, effective and cost-saving approach when treating patients following a heart attack.
Study involving almost 2,500 heart-attack patients
This study, in which 8 Dutch centres were involved, screened patients for specific variants of the CYP2C19 gene that lead to a slow-acting or inactive CYP2C19 enzyme.
People who have such abnormal enzyme activity are at greater risk of suffering a stent thrombosis after an angioplasty when given the anticoagulant clopidogrel. As abnormal CYP2C19 enzyme activity is common, the more expensive drugs ticagrelor and prasugrel are currently used as standard, even though patients without a CYP2C19 mutation could be treated perfectly well with clopidogrel.
The study showed that around 30% of patients had a CYP2C19 gene mutation and only this group received the more expensive drugs. The largest group (almost 70%) had no mutation and was administered the (cheaper) drug clopidogrel. This genotyped group was compared with a control group in which all patients received the standard treatment involving the more expensive drugs ticagrelor and prasugrel.
After the study had ended it was established that there had been no difference in efficacy (anticoagulation) between the standard treatment (in which everyone received ticagrelor or prasugrel) and the genotyped study group (in which ticagrelor and prasugrel were administered only to patients with abnormal CYP2C19 enzyme activity). There were even fewer haemorrhages in the latter group. To summarise, pharmacogenetic screening resulted in fewer side effects and lower costs.
iGene also identifies CYP2C19 gene variants, along with other important pharmacogenetic markers. See here for the complete overview.
Claassens, Daniel MF, et al. "A genotype-guided strategy for oral P2Y12 inhibitors in primary PCI." New England Journal of Medicine (2019).