Evaluation of the relationship between polymorphisms in CYP2C19 and the pharmacokinetics of omeprazole, pantoprazole and rabeprazole.

Aim: To evaluate the possible association between polymorphisms in CYP2C19 and the pharmacokinetics of omeprazole, rabeprazole and pantoprazole.
Materials & Methods: 151 healthy volunteers were evaluated for polymorphisms in the CYP2C19 gene using real-time polymerase chain reaction. Plasma concentrations were measured using high-performance liquid chromatography coupled to mass spectrometry.
Results: Carriers of the *2 allele displayed poor metabolism for all the PPIs studied (around 50% decrease in clearance). Subjects with the *17 allele showed a light increase in clearance compared with *1/*1 (not significant).
Conclusion: CYP2C19*2 is associated with decreased clearance of all the PPIs, that could be associated with higher drug efficacy. CYP2C19*17 could increase clearance of these drugs, although the effect seems small.