Adjunctive Cilostazol Versus High Maintenance-dose Clopidogrel According to Cytochrome 2C19 Polymorphism — ACCEL-2C19  

Coronary Artery Disease Clinical Trial

Official title: CYP 2C19 Polymorphism and Response to Adjunctive Cilostazol and High Maintenance-dose Clopidogrel in Patients Undergoing Elective Percutaneous Coronary Intervention

Status Completed

Clinical Trial Summary

The purpose of this study is to determine the impact of adjunctive cilostazol versus high maintenance-dose clopidogrel on platelet inhibition in carriers and non-carriers of the loss-of-function CYP2C19 mutant allele.

Clinical Trial Description

The additional platelet inhibition with clopidogrel, a thienopyridine inhibitor of the platelet P2Y12 adenosine diphosphate (ADP) receptor, has reduced the risk of ischemic events after coronary stent implantation. Because of inter-individual variability in platelet response to clopidogrel, a significant proportion of suboptimal platelet inhibition has been reported. In addition, persistent residual platelet reactivity measured with platelet function testing has shown the association with the cardiovascular outcomes after percutaneous coronary intervention (PCI).

Various clinical factors and genetic polymorphisms have been studied to predict the degree of antiplatelet response to clopidogrel. Interestingly, recent studies found that carriers of the loss-of-function hepatic cytochrome (CYP) 2C19 allele had significantly lower levels of the active metabolite of clopidogrel, diminished platelet inhibition, and a higher rate of major adverse cardiovascular events than did non-carriers, in the setting of PCI and acute coronary syndrome (ACS). These findings raise the need of solutions to overcome enhanced post-clopidogrel platelet reactivity by the influence of the loss-of-function CYP2C19 allele. Increasing the dose of clopidogrel and new potent P2Y12 antagonists (such as prasugrel) may be alternative antiplatelet regimens in patients with the loss-of-function CYP variant.

Cilostazol reversibly induces platelet inhibition via its blockade of phosphodiesterase (PDE) type 3 and is catalysed mainly by CYP3A. A recent study demonstrated that adjunctive cilostazol to dual antiplatelet therapy (triple antiplatelet therapy) intensified platelet inhibition as compared with a high maintenance-dose (MD) of 150 mg/day. Therefore, triple antiplatelet therapy could also be an alternative antiplatelet therapy to improve platelet inhibition and clinical outcomes in carriers of CYP2C19 mutant allele.

We compared the enhanced inhibition of platelet aggregation by adjunctive cilostazol 100 mg twice daily versus high-MD clopidogrel 150 mg/day in patients treated with elective coronary stenting, according to the CYP2C19 polymorphism. ;

Study Design

Allocation: Randomized, Endpoint Classification: Pharmacokinetics/Dynamics Study, Intervention Model: Parallel Assignment, Masking: Single Blind (Investigator), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Coronary Artery Disease
• Coronary Disease
• Myocardial Ischemia
• Percutaneous Coronary Intervention

• NCT number: NCT01012193
• Study type: Interventional
• Source: Gyeongsang National University Hospital
• Status: Completed
• Phase: Phase 4
• Start date: January 2008
• Completion date: September 2009