The Comparison of Effects Between Increased Dose of Clopidogrel and Addition of Cilostazol

Official Title: “The Comparison of Effects Between Increased Dose of Clopidogrel and Addition of Cilostazol in Clopidogrel Non-Responders After Drug-Eluting Stent Implantation”

To compare the effect of increased dosing of clopidogrel and adding cilostazol to standard dose of clopidogrel after the insertion of drug-eluting stent in patients with clopidogrel resistance

Using dual antiplatelet agents with aspirin and clopidogrel is essential after drug-eluting stent implantation to prevent restenosis and stent thrombosis. However, variable platelet response and potential resistance to therapy have emerged with clopidogrel. Several studies showed that clopidogrel resistance is associated with increased cardiovascular events after coronary interventions. New antiplatelet therapeutic strategy of is needed in case of clopidogrel resistance. We started this study to compare the effect of double dosing of clopidogrel to 150mg per day and adding cilostazol to standard dose of clopidogrel after the insertion of drug-eluting stent in patients with clopidogrel resistance.

Intervention(s) in this Clinical Trial

• Drug: aspirin, clopidogrel
  • aspirin 100 mg plus clopidogrel 150mg qd
• Drug: aspirin, clopidogrel, cilostazol
  • aspirin 100mg qd,clopidogrel 75mg qd plus cilostazol 100mg bid

Arms, Groups and Cohorts in this Clinical Trial

• Experimental: A
  • Aspirin plus increasing clopidogrel group
• Experimental: B
  • Aspirin, clopidogrel plus cilostazol group

Primary Measures

• % platelet inhibition with VeryfyNow-P2Y12 assay, platelet function test
  • Time Frame: 4 weeks
    Safety Issue?: No

Secondary Measures

• P2Y12 reaction unit (PRU)
  • Time Frame: 4 weeks
    Safety Issue?: No

Inclusion Criteria:

• Patient with clopidogrel resistance with treatment of dual antiplatelet agent, aspirin and clopidogrel, for more than 4 weeks after drug-eluting stent
• Clopidogrel resistance is defined as a patients with platelet inhibition less than 30% in platelet function test(VerifyNow-P2Y12 assayTM, Accumetrics, San Diego, CA, USA)

Exclusion Criteria:

• Acute myocardial infarction within 2 weeks
• Unstable angina within 2 weeks
• History of using glycoprotein IIb/IIIa inhibitor within 1 month
• Cerebral infarction within 3 months
• Bleeding diathesis like coagulation disorder, thrombocytopenia (platelet count <
• 100,000/uL)
• history of gastrointestinal bleeding or genitourinary bleeding within 3 months
• needed oral anticoagulation
• aspirin, clopidogrel or cilostazol hypersensitivity
• congestive heart failure
• serum creatinine level >2mg/dl
• malignancy
• using cytochrome P450 inhibitor (eg, itraconazole)

Gender Eligibility for this Clinical Trial: Both

Minimum Age for this Clinical Trial: N/A

Maximum Age for this Clinical Trial: N/A

Are Healthy Volunteers Accepted for this Clinical Trial?: No

Lead Investigator: Samsung Medical Center Other

Overall Clinical Trial Officials and Contacts

Hyeon-Cheol Gwon, MD, PhD Principal Investigator Samsung Medical Center  

Information obtained from ClinicalTrials.gov on February 12, 2012

Link to the current ClinicalTrials.gov record. http://clinicaltrials.gov/show/NCT00620646

Study ID Number: 2006-12-026

ClinicalTrials.gov Identifier: NCT00620646

Health Authority: South Korea: Institutional Review Board