Comparative study of Helicobacter pylori eradication rates of twice-versus four-times-daily amoxicillin administered with proton pump inhibitor and clarithromycin: a randomized study

Background: Proton pump inhibitor (PPI)-containing triple therapy with clarithromycin and amoxicillin is now a standard regimen for Helicobacter pylori eradication in Korea. Amoxicillin has time-dependent bactericidal activity against H. pylori ; we therefore assumed a dosing schedule of amoxicillin would affect the eradication rate of H. pylori . The purpose of this study was to evaluate and compare the efficacy of different amoxicillin dosing schedules for the eradication of H. pylori .
Materials and Methods: One hundred and eighty-six patients with H. pylori infection were eligible for this study. Patients were randomly assigned to one of two regimens: amoxicillin 1000 mg with clarithromycin 500 mg and omeprazole 20 mg twice daily for 2 weeks (BID group, n = 93), or amoxicillin 500 mg four times daily with clarithromycin 500 mg and omeprazole 20 mg twice daily for 2 weeks (QID group, n = 93). The success of H. pylori eradication was evaluated 4–5 weeks after completing treatment.
Results: Overall eradication rate was 90.3%, and eradication rates were 91.4% in the BID group and 89.2% in the QID group ( p  = 0.62). Compliances was 95.7% in the BID group and 93.5% in the QID group ( p  = 0.516); this was the only factor that significantly affected H. pylori eradication in this study. Side effects in both groups were generally mild.
Conclusions: Amoxicillin regimens with PPI and clarithromycin are found to be equally effective and safe in both the BID and QID groups for H. pylori eradication. Therefore, considering patient's comfort, we recommend a twice daily amoxicillin regimen.