Effect of genetic differences in omeprazole metabolism on cure rates for Helicobacter pylori infection and peptic ulcer.
BACKGROUND
Omeprazole is metabolized by S-mephenytoin 4'-hydroxylase (CYP2C19) in the liver. In persons with a poor-metabolizer genotype for CYP2C19, the therapeutic efficacy of omeprazole may be increased.


OBJECTIVE
To investigate whether CYP2C19 genotype status is associated with cure rates for Helicobacterpylori infection and peptic ulcer achieved by using dual therapy with omeprazole and amoxicillin.


METHODS
Prospective cohort study.


METHODS
University hospital and health service center in Hamamatsu, Japan.


METHODS
62 patients with peptic ulcer and H. pylori infection.


METHODS
Omeprazole and amoxicillin.


METHODS
CYP2C19 genotype status and cure rates for H. pylori infection and peptic ulcer.


RESULTS
Cure rates for H. pylori infection were 28.6% (95% CI, 13.1% to 48.7%), 60% (CI, 38.6% to 83.0%), and 100% (CI, 66.4% to 100%) in the rapid-, intermediate-, and poor-metabolizer groups, respectively. Healing rates for both duodenal and gastric ulcer in the three groups were roughly parallel with cure rates for H. pylori infection.


CONCLUSIONS
The results of the genotyping test for CYP2C19 seem to predict cure of H. pylori infection and peptic ulcer in patients who receive dual therapy with omeprazole and amoxicillin.
Furuta
T
T
Hamamatsu University School of Medicine and Honda Motor Co., Ltd., Japan. furuta@akiha.hama-med.ac.jp
Ohashi
K
K
Kamata
T
T
Takashima
M
M
Kosuge
K
K
Kawasaki
T
T
Hanai
H
H
Kubota
T
T
Ishizaki
T
T
Kaneko
E
E
D000328:Adult; D000658:Amoxicillin / Q000627:therapeutic use; D000897:Anti-Ulcer Agents / Q000493:pharmacokinetics* / Q000627:therapeutic use; D001189:Aryl Hydrocarbon Hydroxylases; D065731:Cytochrome P-450 CYP2C19; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism; D004359:Drug Therapy, Combination; D005260:Female; D005838:Genotype; D016481:Helicobacter Infections / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism*; D016480:Helicobacter pylori; D006801:Humans; D008099:Liver / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D006899:Mixed Function Oxygenases / Q000235:genetics / Q000378:metabolism; D009853:Omeprazole / Q000493:pharmacokinetics* / Q000627:therapeutic use; D010406:Penicillins / Q000627:therapeutic use; D010437:Peptic Ulcer / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D011446:Prospective Studies
D000897:Anti-Ulcer Agents; D010406:Penicillins; D000658:Amoxicillin; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D001189:Aryl Hydrocarbon Hydroxylases; C045793:CYP2C19 protein, human; D065731:Cytochrome P-450 CYP2C19; D009853:Omeprazole