Effect of gender and CYP2C9 and CYP2C8 polymorphisms on the pharmacokinetics of ibuprofen enantiomers

Aim: To evaluate the effect of polymorphisms in CYP2C9 and CYP2C8 and gender on the pharmacokinetics of the enantiomeric forms of ibuprofen. Materials & methods: 122 healthy volunteers were genotyped for polymorphisms in CY2C8 and CYP2C9 using real-time PCR. Results:CYP2C8 polymorphisms affected neither R- nor S-ibuprofen. CYP2C9*3 and CYP2C9*2 carriers had a lower S-ibuprofen clearance and a higher S-ibuprofen AUC and half-life. R-ibuprofen clearance was decreased in CYP2C9*3 carriers. Gender affected R-ibuprofen and S-ibuprofen pharmacokinetics. Multiple regression analysis showed that CYP2C9*2, CYP2C9*3 and gender were associated with S-ibuprofen clearance, but only CYP2C9*3 was associated with R-ibuprofen clearance. Conclusion: The pharmacokinetics of S-ibuprofen and R-ibuprofen is affected by CYP2C9 polymorphisms and gender. CYP2C8 polymorphisms do not have a significant role. Original submitted 6 February 2015; Revision submitted 1 April 2015