Improved Eradication Rate of Standard Triple Therapy by Adding Bismuth and Probiotic Supplement for Helicobacter pylori Treatment in Thailand

Background: Helicobacter pylori (H. pylori) remains an important cause of gastric cancer and peptic ulcer disease worldwide. Treatment of H. pylori infection is one of the effective ways to prevent gastric cancer. However, standard triple therapy for H. pylori eradication is no longer effective in many countries, including Thailand. This study was designed to evaluate the efficacy of adding bismuth and probiotic to standard triple therapy for H. pylori eradication. Materials and Methods: In this prospective single center study, H. pylori infected gastritis patients were randomized to receive 7- or 14-day standard triple therapy plus bismuth with probiotic or placebo. Treatment regimen consisted of 30 mg lansoprazole twice daily, 1 g amoxicillin twice daily, 1 g clarithromycin MR once daily and 1,048mg bismuth subsalicylate twice daily. Probiotic bacteria composed of Bifidobacterium lactis, Lactobacillus acidophilus and Lactobacillus paracasei. Placebo was conventional drinking yogurt without probiotic. CYP2C19 genotyping and antibiotic susceptibility tests were also done. H pylori eradication was defined as a negative $^{13}C$-urea breath test at least 2 weeks after completion of treatment. Results: One hundred subjects were enrolled (25 each to 7- and 14-day regimens with probiotic or placebo). Antibiotic susceptibility tests showed 36.7% metronidazole and 1.1% clarithromycin resistance. CYP2C19 genotyping revealed 40.8%, 49% and 10.2% were rapid, intermediate and poor metabolizers, respectively. The eradication rates of 7- or 14 regimens with probiotics were 100%. Regarding adverse events, the incidence of bitter taste was significantly lower in the 7- day regimen with the probiotic group compared with 7- day regimen with placebo (40% vs. 64%; p=0.04). Conclusions: The 7-day standard triple therapy plus bismuth and probiotic can provide an excellent cure rate of H. pylori (100%) in areas with low clarithromycin resistance such as Thailand, regardless of CYP2C19 genotype. Adding a probiotic also reduced treatment-related adverse events.