Modified sequential Helicobacter Pylori eradication therapy using high dose omeprazole and amoxicillin in the initial phase in the extensive metaboliser turkish patients for CYP2C19 polymorphism is ineffective

Aim : To investigate whether the sequential therapy composed of high dose omeprazole and high dose amoxicillin in the first step was effective in eradication of H. pylori and whether there was a relation between effectiveness of the therapy and CYP2C19 gene polymorphism. Method : 134 dyspeptic patients with H. pylori were adminis- tered a modified sequential therapy composed of omeprazole 40 mg t.i.d. and amoxicillin 1000 mg t.i.d. for the first five days followed by omeprazole 20 mg b.d., metronidazole 500 mg t.i.d. and tetra- cycline 500 mg t.i.d. for the next five days. CYP2C19 genotype status was determined in patients. Hp eradication status was inves- tigated by C14 UNT four weeks after treatment. Results : The eradication rates were 64,9% in ITT and 74,3% in PP analysis. In subgroup analyses, eradication rates were 73,8% and 60,8% (p : 0,145) in ITT for peptic ulcer and non-ulcer dyspep- sia patients respectively and 86,1% and 69,1% (p : 0,052) in PP analysis for peptic ulcer and non-ulcer dyspepsia patients respec- tively. The difference was not significant. As for the CYP2C19 gene status, 81,5% of the patients had HoeM and 17,3% of the patients had HeEM, and eradication rates were 72% and 75% in ITT analysis for HoeM and HeEM respectively (p : 0.803) and 73.9% and 85.7% in PP analysis for HoeM and HeEM respectively (p : 0.347). There was not a significant difference in H. pylori eradica- tion rates between the two groups. Conclusion : This modified high-dose sequential therapy was ineffective in a Turkish sample, nearly all of whom had EM in terms of CYP2C19 gene status. (Acta gastroenterol. belg., 2014, 77, 3-7).