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Improving CYP2C19 phenotyping using stereoselective omeprazole and 5‐hydroxy‐omeprazole metabolic ratios

Year: 2024
Type: article
Abstract: Omeprazole (OME) is a CYP2C19 phenotyping probe, marketed as a racemic (S)/(R) mixture or as an S-enantiomer. Both CYP2C19 and CYP3A4 enzymes mediate (R)-OME hydroxylation to (R)-5-hydroxyomeprazole, while (S)-OME is exclusively hydroxylated via CYP2C19. This study investigates OME and its 5-hydroxymetabolite enantiomers' pharmacokinetics using data from two studies involving healthy volunteers. In Study A, volunteers received OME alone in Session 1, OME combined with voriconazole and fluvoxamine in Session 2 and finally OME with rifampicin in Session 3. In Study B, volunteers received OME alone in Session 1, OME combined with voriconazole in Session 2 and finally OME with fluvoxamine in Session 3. Despite low metabolic ratio values of (S)-OME, detectable modulation of CYP2C19 activity suggests both (R)- and (S)-OME isomers could effectively assess CYP2C19 activity. Further research is needed for precise cut-offs in different phenotype groups.
Language: English
Subfield: Pharmacology
Open Access status: hybrid
Estimated APC paid: $4,430
OpenAlex ID: W4403302645
FWCI: 1.094
Cites: 16
Cited by: 3
Related to: 10