Genotyping makes some antiplatelet therapy more cost-effective

Tailoring antiplatelet therapy based on a person’s genetic information may be a cost-effective strategy when using prasugrel and ticagrelor after PCI, a study published online Feb. 17 in Annals of Internal Medicine found. In addition, the study found that ticagrelor may be cost-effective for all patients without the need for genotyping.

Clopidogrel (Plavix, Bristol-Myers Squibb) is typically the drug of choice after PCI, but it may cause more bleeding or thrombotic events in patients related to differences in the cytochrome P450 2C19 (CYP2C19) gene. Available testing has made it possible to tailor antiplatelet therapy based on genetics using new and more expensive drugs. The authors, led by Dhruv S. Kazi, MD, MSc, MS, of San Francisco General Hospital, sought to determine which dual antiplatelet therapy is most cost-effective.

Researchers conducted a cost-effectiveness analysis that compared drug-only strategies using clopidogrel, prasugrel (Daiichi Sankyo and Lilly USA) and ticagrelor (Brilinta, AstraZeneca) and strategies based on genotype using ticagrelor or prasugrel. As outcomes, they looked at direct costs, quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs).

They based their cost analysis on base-case cost of $30 per month for generic clopidogrel and also used the average wholesale price of $218 per month for the proprietary form. For prasugrel and ticagrelor, they used $220 and $261 per month. They also estimated the cost of genetic testing based on the different retail costs.

The investigators concluded that tailoring therapy based on genotype could make newer antiplatelet drugs more cost-effective.

The use of clopidogrel led to $179,301 in costs and 9,428 QALYs. Prasugrel along with genetic testing was better than prasugrel on its own, with an ICER of $35,800 per QALY compared with clopidogrel. Genotyping with ticagrelor was more cost-effective than genotyping with prasugrel ($30,200 per QALY compared to clopidogrel).

Using ticagrelor for all patients produced the highest QALYs, but it was also the most expensive. The ICER was $52,600 per QALY compared to genetic testing with ticagrelor.

The sensitivity analysis revealed that ticagrelor was considerably less cost-effective ($104,800 per QALY) because of the risk of thrombotic outcomes related to genotype. Genotyping prasugrel was the preferred strategy for patients unable to tolerate ticagrelor.

“Based on currently available evidence, genotyping patients having PCI for ACS [acute coronary syndrome], followed by the targeted use of ticagrelor in carriers of loss-of-function CYP2C19 alleles and clopidogrel in noncarriers is economically attractive compared with treating all patients with the newer agents or clopidogrel,” wrote the authors.

They also noted that ticagrelor for all patients may be a feasible alternative, but future research should focus on learning more about the newer drugs as well as prospectively assessing the role of tailoring antiplatelet therapy in these patients.