High-dose proton pump inhibitor plus amoxycillin for the treatment or retreatment of Helicobacter pylori infection

Background : The combination of 120 mg of omeprazole (40 mg t.d.s.) and amoxycillin has been reported to be effective for treating H. pylori infections.
Methods : Normal volunteers with H. pylori infection received high-dose omeprazole (40 mg t.d.s.) or lansoprazole (60 mg t.d.s.) plus amoxycillin 750 mg t.d.s. for 14 days. The studies were open label and not randomized as those receiving omeprazole plus amoxycillin had previously failed lower dose omeprazole (20 mg b.d.) plus amoxycillin therapy more than 6 months previously. Those receiving lansoprazole plus amoxycillin had not been previously treated. Four to 6 weeks after ending antimicrobial therapy, H. pylori status was determined by Genta stain of gastric mucosal biopsies.
Results : Forty-three volunteers entered the study and 41 completed it. The overall success with high-dose proton pump inhibitor plus amoxycillin was 34.9%. For the individual regimens the per-protocol results were 48% (95% CI=28–69%) with lansoprazole and 12.5% (95% CI=2–38%) with omeprazole. Compliance was >95% for both regimens. Side-effects were experienced by four lansoprazole and three omeprazole subjects, and caused two omeprazole subjects to withdraw. Cure rates were similar among different races and ethnic groups, between men and women, and between smokers and non-smokers. The level of the pre-treatment urea breath test also did not predict outcome.
Conclusion : High-dose proton pump inhibitor plus amoxycillin combinations for treatment of H. pylori infection yielded unacceptable results, as the 95% confidence intervals did not include an 80% cure rate. These combinations do not yield consistent results worldwide and cannot be recommended as primary therapy.