Helicobacter Pylori Treatment Failure Clinical Trial
Official title:
Prospective, Randomized Controlled Trial Comparing High Dose Amoxicillin Versus Tetracycline Based Quadruple Therapy as Second-line Treatment for Resistant Helicobacter Pylori Infection
No trial has examined the the efficacy of high dose amoxicillin based quadruple therapy as second-line treatment for Helicobacter pylori infection. The study aims to compare the effectiveness and safety of 14-day high dose amoxicillin-based quadruple regiment with classical quadruple regiment for rescue eradication of Helicobacter pylori.
Helicobacter pylori is the most successful human pathogen infecting an estimated 50% of the
global population, and is associated with a spectrum of disease states, including chronic
gastritis, duodenal and gastric ulcer, gastric adenocarcinoma, and gastric mucosa-associated
lymphoid tissue lymphoma (MALToma).
Most Consensus Conferences and Clinical Guidelines recommend the prescription of a triple
therapy including a proton pump inhibitor (PPI) and clarithromycin with either amoxicillin or
metronidazole, as first-line treatment. However, the effectiveness of these triple-therapy
regimens seems to have diminished over time, largely as a result of emerging resistance of
the organism to clarithromycin. Avoiding problems due to antibiotic resistance has become an
important issue when deciding a second-line rescue therapy for H. pylori infection
Bismuth-containing quadruple therapies have been used widely in second-line therapy of H.
pylori infection, and are recommended by the Maastricht IV Consensus Conference report.
Quadruple therapy can achieve a high rate of eradication success as a second-line treatment.
A meta-analysis of quadruple therapy showed that metronidazole resistance had limited effect
on the outcome when adequate dosages and durations are used. This meta-analysis also showed
that compliance with quadruple therapy is high. Classical bismuth-based quadruple therapy
consists of a PPI, bismuth, tetracycline and metronidazole. This regiment meets the proposed
criteria for a second-line treatment: it does not contain the key antibiotic of the original
regimen (clarithromycin), the treatment is not affected by clarithromycin resistance,
metronidazole resistance in vitro does not affect the outcome of quadruple therapy
significantly, compliance with the regimen is high and the regimen is effective in most parts
of the world. But this regiment has high rate of side effects because of tetracycline.
Amoxicillin has low resistance rate as well as low percentage of side effects. The
replacement of tetracycline by high dose amoxicillin in classical bismuth-containing
quadruple therapy may be a better choice. Therefore, we will do a randomized trial to compare
the eradication rate of 14-day high dose amoxicillin and metronidazole based
bismuth-containing quadruple therapy with classical quadruple therapy for second-line
Helicobacter pylori treatment.
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