14-Day High-Dose Amoxicillin- and Metronidazole-Containing Triple Therapy With or Without Bismuth as First-Line Helicobacter pylori Treatment.

BACKGROUND

Amoxicillin, metronidazole, proton pump inhibitor, bismuth quadruple therapy had been shown to reliably achieve high eradication rates. The role of individual components remains undefined.

AIM: To identify the additional benefit/role of bismuth in amoxicillin, metronidazole, proton pump inhibitor, bismuth quadruple therapy for Helicobacter pylori (H. pylori) treatment.

METHODS

This was a non-inferiority factorial design trial. Treatment-naive H. pylori-infected subjects were randomly (1:1) assigned to receive 14-day amoxicillin- and metronidazole-containing triple therapy consisting of esomeprazole 20 mg twice a day, amoxicillin 1 g, and metronidazole 400 mg both thrice daily with or without 220 mg bismuth twice a day. Six weeks after treatment, H. pylori eradication was assessed by 13C-urea breath test. Antimicrobial susceptibility was assessed by the twofold agar dilution method.

RESULTS

From July 2018 to June 2019, a total of two hundred and sixteen subjects were randomized. Both therapies achieved high eradication rates. Per-protocol with bismuth = 97.9% (94/96, 95% CI 95.1-100%) and without bismuth = 94.7% (90/95, 95% CI 90.3-99.1%) (P = 0.43). Intent-to-treat analysis = 90.7% (98/108, 95% CI 85.2-96.2%) versus 88.9% (96/108, 95% CI 82.8-95.0%) with and without bismuth (P = 0.65). The two regimens were not inferior by intent-to-treat or per-protocol analyses. Metronidazole resistance did not affect the efficacy of either therapy.

CONCLUSION

Neither the presence nor absence of bismuth or metronidazole resistance reduced the effectiveness of triple therapy containing esomeprazole 20 mg twice a day, amoxicillin 1 g, and metronidazole 400 mg thrice daily in this population. The clinical trial was registered with ClinicalTrials.gov, NCT03557437.