Possible interaction between clopidogrel and CYP3A4-metabolised atorvastatin or non-CYP3A4-metabolised rosuvastatin was investigated based on pharmacokinetic parameters of clopidogrel and its metabolites as well as the platelet reactivity test in patients undergoing coronary angiography/angioplasty.

The study involved 50 patients (62.7 ± 7.8 years old) who underwent coronary angiography/angioplasty and were treated with clopidogrel and atorvastatin or rosuvastatin during the six months after the procedure. The P2Y12 reaction units (PRU) and pharmacokinetic parameters of clopidogrel, diastereoisomers of thiol metabolite (inactive H3 and active H4), and inactive carboxylic metabolite were measured 12–18 h and six months after the coronary angiography/angioplasty.

There were no significant differences in concentrations of clopidogrel and its metabolites including the H4 active metabolite in plasma of patients co-treated with clopidogrel and atorvastatin or rosuvastatin. The use of statins did not affect the pharmacokinetic parameters of the studied compounds. A significant correlation was found between the C_max and AUC_0-t of the active H4 isomer and platelet aggregation in a group of patients treated with rosuvastatin but not in the atorvastatin group. No significant differences in PRU values were observed between the atorvastatin and rosuvastatin groups at the beginning of the study (171.4 ± 54.3 vs 146.3 ± 48.1 PRU, p = 0.192) as well as at six months (173.7 ± 45.8 vs 157.3 ± 54.9 PRU, p = 0.562). However, in a small group of patients, who were discharged from atorvastatin to rosuvastatin, an increase in the PRU values accompanied by a decreased AUC of the H4 active isomer was observed.

The study confirmed that the systemic exposure to clopidogrel and its active H4 isomer of thiol metabolite, as well as the antiplatelet effect of the drug, were not negatively affected by co-administration of atorvastatin as compared with rosuvastatin.