Evaluation of Bismuth-clarithromycin-containing Quadruple Therapy for Initial Helicobacter pylori Eradication

Background: Eradication rate of standard triple therapy for Helicobacter pylori(H.pylori) infection is decreasing recently.It is urgent to look for a novel,safe and effective regimen.Aims: To assess the efficacy and safety of bismuth-clarithromycin-containing quadruple regimen as a primary therapy for H.pylori eradication.Methods: A total of 120 H.pylori-infected patients with non-ulcer dyspepsia diagnosed by gastroscopy were enrolled and randomly assigned into three groups: 7-day triple therapy(omeprazole 20 mg bid,amoxicillin 1000 mg bid and clarithromycin 500 mg bid for 7 days),7-day quadruple therapy(7-day triple therapy plus bismuth potassium citrate 220 mg bid for 7 days) and 2-week quadruple therapy(7-day quadruple therapy for 2 weeks).At least four weeks after the end of treatment,H.pylori eradication was assessed by 13C-urea breath test.H.pylori strains isolated were tested for clarithromycin,metronidazole and amoxicillin resistance.Results: A total of 115 patients completed the study.H.pylori eradication rates by intention-to-treat(ITT) analysis in 7-day triple therapy,7-day quadruple therapy,2-week quadruple therapy were 70.0%,75.0%,90.0%,respectively;by per-protocol(PP) analysis were 73.7%,76.9%,94.7%,respectively.The eradication rate in 2-week quadruple therapy was significantly higher than that in 7-day triple therapy by both ITT and PP analysis(P0.05),and was significantly higher than that in 7-day quadruple therapy by PP analysis(P=0.026).No significant difference in eradication rate by ITT and PP analysis was found between 7-day triple therapy and 7-day quadruple therapy.The resistance rates of H.pylori to clarithromycin,metronidazole and amoxicillin were 24.2%,48.3%,0%,respectively.The eradication rates of 7-day triple therapy,7-day quadruple therapy and 2-week quadruple therapy in patients with clarithromycin-resistant strains increased stepwisely(37.5%,55.6%,80.0%),but not reached statistical significance.Except one patient in 2-week quadruple therapy could not complete the course of treatment due to skin allergy,other patients in all three groups had slight and similar side-effects and all were well tolerated.Conclusions: Two-week bismuth-clarithromycin-containing quadruple therapy can increase the eradication rate of H.pylori with safety,and could be used as the first line eradication regimen.