The Efficacy of Bismuth-containing Quadruple Therapy after Moxifloxacin-based Sequential Therapy Failure in Helicobacter pylori Eradication

Background/Aims: Moxifloxacin-based sequential therapy showed an excellent eradication rate as the first line treatment of Helicobacter pylori (H. pylori) infection. However, to the best of our knowledge, there were only a few studies on the treatment of those with failed moxifloxacin-based sequential therapy. Hence, this study was to investigate the efficacy of bismuth-containing quadruple therapy in those with failed moxifloxacin-based sequential or reverse sequential therapy for H. pylori eradication. Methods: Between January 2013 and March 2016, we retrospectively analyzed patients who failed to eradicate H. pylori using moxifloxacin-based sequential (rabeprazole 20 mg bid and amoxicillin 1 g bid for 5-7 days, followed by rabeprazole 20 mg bid, metronidazole 500 mg bid, and moxifloxacin 400 mg qd for 5-7 days) and 10 days moxifloxacin-based reverse sequential therapy as the first line treatment. Then we investigated the eradication rates of bismuth-containing quadruple therapy as the second line treatment. All subjects had no history of H. pylori eradication before. Eradication rates were described as intention-to-treat (ITT) and per-protocol (PP) analyses. H. pylori status was evaluated by 13C-urea breath test 6 weeks after the end of the treatment. Moreover, we examined any side effects that caused discontinuation of therapy. Results: Twenty-three patients received bismuth-containing quadruple therapy as the second line treatment. The overall eradication rates by ITT and PP analyses were 60.87% (n=14/23) and 73.68% (n=14/19). All the patients showed good compliance, and there were no serious adverse events. Conclusions: Bismuth-containing quadruple therapy is insufficient as the second line eradication treatment after a failed attempt of moxifloxacin-based sequential or reverse sequential therapy. Large-scale clinical trials should be performed to establish better clinical evidence.