TY - JOUR
T1 - Impact of P-glycoprotein on clopidogrel absorption
AU - Taubert, Dirk
AU - von Beckerath, Nicolas
AU - Grimberg, Gundula
AU - Lazar, Andreas
AU - Jung, Norma
AU - Goeser, Tobias
AU - Kastrati, Adnan
AU - Schömig, Albert
AU - Schömig, Edgar
PY - 2006/11
Y1 - 2006/11
N2 - Objective: The antiplatelet activity of clopidogrel is characterized by considerable interindividual differences. Variable intestinal absorption is suggested to contribute to the inconsistencies in response. We tested the hypothesis that the intestinal efflux transporter P-glycoprotein (P-gp) limits the oral bioavailability of clopidogrel and that variance in the MDR1 gene encoding P-gp predicts absorption variability. Methods and Results: P-gp-mediated transport of clopidogrel was assessed by transflux, influx, and efflux experiments by use of Caco-2 cells. Inhibition of P-gp activity by different modulators increased the absorptive clopidogrel flux across Caco-2 monolayers from 0.51 ± 0.19 pmol/cm2 (mean ± SD) at baseline by a maximum of 5- to 9-fold (P < .001) and the intracellular accumulation from 0.99 ± 0.11 pmol/mg protein by a maximum of 2.5-fold (P < .001) in response to 1-μmol/L clopidogrel and decreased clopidogrel efflux to the level of passive diffusion. In 60 patients with coronary artery disease who underwent percutaneous coronary intervention, the peak plasma concentration (Cmax) and the total area under the plasma concentration-time curve (AUC) of clopidogrel and its active metabolite after a single oral loading dose of 300, 600, or 900 mg were tested for correlation with the MDR1 genotype. In the 300-mg and 600-mg groups (but not in the 900-mg group) Cmax and AUC values were lower in subjects homozygous for the MDR1 3435T variant compared with subjects with the 3435C/T and 3435C/C genotypes. After the 600-mg loading dose, Cmax values (mean ± SD) of clopidogrel and its active metabolite in 3435T/T carriers were 13.3 ± 5.2 ng/mL and 2.5 ± 1.2 ng/mL, respectively, compared with 49.7 ± 41.6 ng/mL (P = .001) and 6.6 ± 3.6 ng/mL (P = .011), respectively, in 3435C/T and 3435C/C carriers; AUC values were 1502 ± 463 ng/mL × min for clopidogrel and 209 ± 99 ng/mL × min for its active metabolite in 3435T/T carriers compared with 7057 ± 5443 ng/mL × min (P = .0006) and 744 ± 541 ng/mL × min (P = .011), respectively, in 3435C/T and 3435C/C carriers. Conclusions: Clopidogrel absorption and thereby active metabolite formation are diminished by P-gp-mediated efflux and are influenced by the MDR1 C3435T genotype.
AB - Objective: The antiplatelet activity of clopidogrel is characterized by considerable interindividual differences. Variable intestinal absorption is suggested to contribute to the inconsistencies in response. We tested the hypothesis that the intestinal efflux transporter P-glycoprotein (P-gp) limits the oral bioavailability of clopidogrel and that variance in the MDR1 gene encoding P-gp predicts absorption variability. Methods and Results: P-gp-mediated transport of clopidogrel was assessed by transflux, influx, and efflux experiments by use of Caco-2 cells. Inhibition of P-gp activity by different modulators increased the absorptive clopidogrel flux across Caco-2 monolayers from 0.51 ± 0.19 pmol/cm2 (mean ± SD) at baseline by a maximum of 5- to 9-fold (P < .001) and the intracellular accumulation from 0.99 ± 0.11 pmol/mg protein by a maximum of 2.5-fold (P < .001) in response to 1-μmol/L clopidogrel and decreased clopidogrel efflux to the level of passive diffusion. In 60 patients with coronary artery disease who underwent percutaneous coronary intervention, the peak plasma concentration (Cmax) and the total area under the plasma concentration-time curve (AUC) of clopidogrel and its active metabolite after a single oral loading dose of 300, 600, or 900 mg were tested for correlation with the MDR1 genotype. In the 300-mg and 600-mg groups (but not in the 900-mg group) Cmax and AUC values were lower in subjects homozygous for the MDR1 3435T variant compared with subjects with the 3435C/T and 3435C/C genotypes. After the 600-mg loading dose, Cmax values (mean ± SD) of clopidogrel and its active metabolite in 3435T/T carriers were 13.3 ± 5.2 ng/mL and 2.5 ± 1.2 ng/mL, respectively, compared with 49.7 ± 41.6 ng/mL (P = .001) and 6.6 ± 3.6 ng/mL (P = .011), respectively, in 3435C/T and 3435C/C carriers; AUC values were 1502 ± 463 ng/mL × min for clopidogrel and 209 ± 99 ng/mL × min for its active metabolite in 3435T/T carriers compared with 7057 ± 5443 ng/mL × min (P = .0006) and 744 ± 541 ng/mL × min (P = .011), respectively, in 3435C/T and 3435C/C carriers. Conclusions: Clopidogrel absorption and thereby active metabolite formation are diminished by P-gp-mediated efflux and are influenced by the MDR1 C3435T genotype.
UR - http://www.scopus.com/inward/record.url?scp=33751080762&partnerID=8YFLogxK
U2 - 10.1016/j.clpt.2006.07.007
DO - 10.1016/j.clpt.2006.07.007
M3 - Article
C2 - 17112805
AN - SCOPUS:33751080762
SN - 0009-9236
VL - 80
SP - 486
EP - 501
JO - Clinical Pharmacology and Therapeutics
JF - Clinical Pharmacology and Therapeutics
IS - 5
ER -