Tailored Adjunctive Cilostazol Therapy Based on CYP2C19 Genotyping in Patients With Acute Myocardial Infarction - The CALDERA-GENE Study.

BACKGROUND

Patients with reduced-function CYP2C19 genotypes on dual antiplatelet therapy (DAPT) with aspirin and clopidogrel show higher clinical risk for acute myocardial infarction (AMI). We investigated the effect of CYP2C19 genotype-tailored adjunctive cilostazol therapy on treatment of AMI.

METHODS AND RESULTS

The study group of 138 patients with suspected AMI were screened for CYP2C19 genotype immediately after percutaneous coronary intervention (PCI) using a SPARTAN RX point-of-care device. Carriers of the CYP2C19 reduced-function allele were randomized into DAPT (Carrier/DAPT) and DAPT plus 14-day cilostazol (Carrier/DAPT+Cilostazol) groups, while noncarriers were treated with DAPT (Noncarrier/DAPT). After exclusion of 10 patients, the remaining 128 patients were analyzed for P2Y12 reaction unit (PRU) using VerifyNowP2Y12 system, and levels of biomarkers immediately after, and 1, 14, and 28 days after PCI. DAPT+Cilostazol reduced PRU levels in carriers (n=46) to those found in the Noncarrier/DAPT group (n=40), and significantly lower than those of the Carrier/DAPT group (n=42) at 14 days post-PCI. Discontinuation of cilostazol for 14 days was associated with a significant rise in PRU levels to those of the Carrier/DAPT group at 28 days post-PCI. Plasma B-type natriuretic peptide levels at 14 days post-PCI were lower in Carrier/DAPT+Cilostazol than in the other 2 groups, and the levels increased to those of the other groups at 28 days post-PCI after withdrawal of cilostazol.

CONCLUSIONS

Adjunctive cilostazol therapy tailored to CYP2C19 genotype seemed useful in AMI patients with the CYP2C19 reduced-function allele.