title: Lower loading dose of prasugrel compared with conventional loading doses of clopidogrel and prasugrel in korean patients undergoing elective coronary angiography: a randomized controlled study evaluating pharmacodynamic efficacy.
abstract: OBJECTIVE
  Although prasugrel allows for rapid and potent platelet inhibition, the efficacy and safety of lower doses of prasugrel for patients of East Asian ethnicity has not yet been investigated. We compared the effect of a lower loading dose (LD) of prasugrel with conventional LDs of clopidogrel and prasugrel in Korean patients.
  
  
  METHODS
  Forty-three Korean patients undergoing coronary angiography were enrolled in the study. Participants were randomly administered LDs of clopidogrel 600 mg, prasugrel 30 mg or prasugrel 60 mg prior to coronary angiography. Platelet reactivity was assessed at baseline and at the time of peak platelet inhibition using light transmission aggregometry (LTA), the VerifyNow assay, and multiple electrode aggregometry.
  
  
  RESULTS
  Although baseline platelet reactivity between the groups showed no significant differences, at the time of peak platelet inhibition, the prasugrel 30 mg (18.9±10.0%) and 60 mg groups (13.8±10.8%) showed significantly more potent platelet inhibition than the clopidogrel 600 mg group (52.9±15.8%; p<0.001) by LTA. However, there were no significant differences between the prasugrel 30 mg and 60 mg groups (p=0.549).
  
  
  CONCLUSIONS
  The loading effect of prasugrel 30 mg was more potent than clopidogrel 600 mg and was not significantly different from prasugrel 60 mg.
authors.affiliation: Department of Cardiology, Dong-A University Hospital, Busan, Korea.
authors.forename: Dong Hyun
authors.initials: DH
authors.lastname: Lee
authors.affiliation: Department of Cardiology, Dong-A University Hospital, Busan, Korea. ; Regional Clinical Trial Center, Dong-A University Hospital, Busan, Korea.
authors.forename: Moo Hyun
authors.initials: MH
authors.lastname: Kim
authors.affiliation: Regional Clinical Trial Center, Dong-A University Hospital, Busan, Korea.
authors.forename: Long Zhe
authors.initials: LZ
authors.lastname: Guo
authors.affiliation: Regional Clinical Trial Center, Dong-A University Hospital, Busan, Korea.
authors.forename: Min Kyu
authors.initials: MK
authors.lastname: Park
authors.affiliation: Regional Clinical Trial Center, Dong-A University Hospital, Busan, Korea.
authors.forename: So Jeong
authors.initials: SJ
authors.lastname: Yi
keywords: Clopidogrel; Coronary artery disease; Platelet function tests; Population heterogeneity; Prasugrel