title: Paraoxonase-1 is a major determinant of clopidogrel efficacy.
abstract: Clinical efficacy of the antiplatelet drug clopidogrel is hampered by its variable biotransformation into the active metabolite. The variability in the clinical response to clopidogrel treatment has been attributed to genetic factors, but the specific genes and mechanisms underlying clopidogrel bioactivation remain unclear. Using in vitro metabolomic profiling techniques, we identified paraoxonase-1 (PON1) as the crucial enzyme for clopidogrel bioactivation, with its common Q192R polymorphism determining the rate of active metabolite formation. We tested the clinical relevance of the PON1 Q192R genotype in a population of individuals with coronary artery disease who underwent stent implantation and received clopidogrel therapy. PON1 QQ192 homozygous individuals showed a considerably higher risk than RR192 homozygous individuals of stent thrombosis, lower PON1 plasma activity, lower plasma concentrations of active metabolite and lower platelet inhibition. Thus, we identified PON1 as a key factor for the bioactivation and clinical activity of clopidogrel. These findings have therapeutic implications and may be exploited to prospectively assess the clinical efficacy of clopidogrel.
authors.affiliation: Department of Cardiology, St. Antonius Hospital Nieuwegein, Nieuwegein, The Netherlands.
authors.forename: Heleen J
authors.initials: HJ
authors.lastname: Bouman
authors.forename: Edgar
authors.initials: E
authors.lastname: Schömig
authors.forename: Jochem W
authors.initials: JW
authors.lastname: van Werkum
authors.forename: Janna
authors.initials: J
authors.lastname: Velder
authors.forename: Christian M
authors.initials: CM
authors.lastname: Hackeng
authors.forename: Christoph
authors.initials: C
authors.lastname: Hirschhäuser
authors.forename: Christopher
authors.initials: C
authors.lastname: Waldmann
authors.forename: Hans-Günther
authors.initials: HG
authors.lastname: Schmalz
authors.forename: Jurriën M
authors.initials: JM
authors.lastname: ten Berg
authors.forename: Dirk
authors.initials: D
authors.lastname: Taubert
mesh_terms: D019943:Amino Acid Substitution; D043303:Aryldialkylphosphatase / Q000235:genetics* / Q000378:metabolism*; D001711:Biotransformation; D000077144:Clopidogrel; D003327:Coronary Disease / Q000188:drug therapy / Q000401:mortality / Q000601:surgery*; D005500:Follow-Up Studies; D005838:Genotype; D006720:Homozygote; D006801:Humans; D007700:Kinetics; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D011110:Polymorphism, Genetic; D015607:Stents; D013379:Substrate Specificity; D016019:Survival Analysis; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000627:therapeutic use; D013997:Time Factors
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D043303:Aryldialkylphosphatase; C468406:PON1 protein, human; D013988:Ticlopidine