Effect of Genetic Differences in Omeprazole Metabolism on Cure Rates for Helicobacter pylori Infection and Peptic Ulcer

  1. Takahisa Furuta, MD;
  2. Kyoichi Ohashi, MD;
  3. Takashi Kamata, MD;
  4. Misako Takashima, MD;
  5. Kazuhiro Kosuge, PhD;
  6. Tsunehisa Kawasaki, MD;
  7. Hiroyuki Hanai, MD;
  8. Takahiro Kubota, MS;
  9. Takashi Ishizaki, MD; and
  10. Eizo Kaneko, MD
  1. From Hamamatsu University School of Medicine and Honda Motor Co., Ltd., Hamamatsu, Japan; and SRL, Inc., and International Medical Center of Japan, Tokyo, Japan. Acknowledgments: The authors thank Yasue Noda for PCR restriction fragment length polymorphism analysis of blood samples and thank endoscopy nurses Kiwako Tsuchiya, Miho Ijiri, Rie Suzuki, Tazuko Suzuki, Kayoko Imada, Terumi Yagi, and Emi Ichise for assistance. Grant Support: By Grants-in-Aid for Scientific Research from the Ministry of Education of Japan (08570577 and 10672149). Requests for Reprints: Takahisa Furuta, MD, First Department of Medicine, Hamamatsu University School of Medicine, 3600, Handa-cho, Hamamatsu 431-3192, Japan; e-mail, furuta@akiha.hama-med.ac.jp. Current Author Addresses: Drs. Furuta, Takashima, Hanai, and Kaneko: First Department of Medicine, Hamamatsu University School of Medicine, 3600, Handa-cho, Hamamatsu 431-3192, Japan.

    Abstract

    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 Helicobacter pylori infection and peptic ulcer achieved by using dual therapy with omeprazole and amoxicillin.

    Design: Prospective cohort study.

    Setting: University hospital and health service center in Hamamatsu, Japan.

    Patients: 62 patients with peptic ulcer and H. pylori infection.

    Intervention: Omeprazole and amoxicillin.

    Measurements: 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.

    Conclusion: 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.

    « Previous | Next Article »Table of Contents