Increased omeprazole metabolism in carriers of the CYP2C19*17 allele; a pharmacokinetic study in healthy volunteers

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: The only existing study of CYP2C19*17-associated alterations in drug pharmacokinetics was retrospective and compared probe drug metabolic ratios. The CYP2C19*17 allele had been associated with a two- and fourfold decrease in omeprazole and S/R-mephenytoin metabolic ratios.

WHAT THIS STUDY ADDS: This study characterized the single-dose pharmacokinetics of omeprazole, along with the 5-hydroxy and sulphone metabolites, in CYP2C19*17/*17 and CYP2C19*1/*1 subjects. The observed differences in omeprazole AUC(infinity) suggest that the CYP2C19*17 allele is an important explanatory factor behind individual cases of therapeutic failure. AIMS To investigate the influence of the CYP2C19*17 allele on the pharmacokinetics of omeprazole, a commonly used CYP2C19 probe drug, in healthy volunteers.

METHODS: In a single-dose pharmacokinetic study, 17 healthy White volunteers genotyped as either CYP2C19*17/*17 or CYP2C19*1/*1 received an oral dose of 40 mg of omeprazole. Plasma was sampled for up to 10 h postdose, followed by quantification of omeprazole, 5-hydroxy omeprazole and omeprazole sulphone by high-performance liquid chromatography.

RESULTS: The mean omeprazole AUC(infinity) of 1973 h nmol l(-1) in CYP2C19*17/*17 subjects was 2.1-fold lower [95% confidence interval (CI) 1.1, 3.3] than in CYP2C19*1/*1 subjects (4151 h nmol l(-1), P = 0.04). A similar trend was observed for the sulphone metabolite with the CYP2C19*17/*17 group having a mean AUC(infinity) of 1083 h nmol l(-1), 3.1-fold lower (95% CI 1.2, 5.5) than the CYP2C19*1/*1 group (3343 h nmol l(-1), P = 0.03). A pronounced correlation (r(2) = 0.95, P < 0.0001) was seen in the intraindividual omeprazole AUC(infinity) and omeprazole sulphone AUC(infinity) values.

CONCLUSIONS: The pharmacokinetics of omeprazole and omeprazole sulphone differ significantly between homozygous CYP2C19*17 and CYP2C19*1 subjects. For clinically important drugs that are metabolized predominantly by CYP2C19, the CYP2C19*17 allele might be associated with subtherapeutic drug exposure.

Medienart:

E-Artikel

Erscheinungsjahr:

2008

Erschienen:

2008

Enthalten in:

Zur Gesamtaufnahme - volume:65

Enthalten in:

British journal of clinical pharmacology - 65(2008), 5 vom: 15. Mai, Seite 767-74

Sprache:

Englisch

Beteiligte Personen:

Baldwin, R Michael [VerfasserIn]
Ohlsson, Staffan [VerfasserIn]
Pedersen, Rasmus Steen [VerfasserIn]
Mwinyi, Jessica [VerfasserIn]
Ingelman-Sundberg, Magnus [VerfasserIn]
Eliasson, Erik [VerfasserIn]
Bertilsson, Leif [VerfasserIn]

Links:

Volltext

Themen:

Anti-Ulcer Agents
Aryl Hydrocarbon Hydroxylases
CYP2C19 protein, human
Cytochrome P-450 CYP2C19
EC 1.-
EC 1.14.14.1
Journal Article
KG60484QX9
Mixed Function Oxygenases
Omeprazole
Randomized Controlled Trial
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 23.07.2008

Date Revised 20.10.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1111/j.1365-2125.2008.03104.x

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM177804882