Effects of clarithromycin-containing quadruple therapy on helicobacter pylori eradication after nitroimidazole-containing quadruple therapy failure

Background: Several large clinical trials and meta-analyses have shown about 20% failure to eradicate Helicobacter pylori [H.pylori], necessitating investigations for second-line treatments. The aim of this study was to evaluate the effects of clarithromycin-containing quadruple regimen after nitroimidazole-containing quadruple therapy failure

Methods: Thirty two patients who had failed 10-day H.pylori treatment with omeprazole, amoxicillin, bismuth subcitrate, and metronidazole [OABM] regimen and 31 patients who had failed 10-day treatment with omeprazole, amoxicillin, bismuth subcitrate, and furazolidone [OAMF] regimen entered the study. They all received omeprazole [20 mg], amoxicillin [1 gr], bismuth subcitrate [240 mg] and clarithromycin [500 mg] twice a day for 10 days. Eight weeks after treatment, H. pylori eradication was assessed by 14C-urea breath test

Results: Totally 61 patients completed the study. According to intention to treat [ITT] analysis, eradication rates by second-line OABC regimen were 84.37% [95% CI= 71.7-96.9%] in OABM group and 77.41% [95% CI= 62.71-92.11%] in OABF group [p=0.756]. Per-protocol [pp] eradication rates were 87.09% [95% CI= 75.2-98.8%] and 82.75% [95% CI= 79.4-96%], respectively [p=0.638]. Also the cumulative eradication rates by OABC regimen were 80.9% [95% CI= 71.2-90.6%] and 85% [95% CI= 75.9-94%] according to ITT and PP analyses, respectively. Severe side effects were reported in 3.1% of the patients

Conclusion: Regarding ideal eradication rate [>80%] and very low adverse effects, it seems that clarithromycin-containing quadruple therapy can be an encouraging regimen after nitroimidazole-containing regimen failure

comparison between hybrid and concomitant regimens for helicobacter pylori eradication: a randomized clinical trial

Background: Helicobacter pylori [H. pylori] is one of the most common bacterial infections worldwide. We designed a study to compare the efficacy of 14-day hybrid regimen with 10-day concomitant therapy for H. pylori eradication in Iran

Methods: 252 patients with naive H. pylori infection were randomly divided to receive either hybrid regimen [pantoprazole 40 mg, and amoxicillin 1 gr twice daily for 14 days, accompanied by clarithromycin 500 mg, and metronidazole 500 mg, twice daily just during the last 7 days] or concomitant regimen [pantoprazole 40 mg, amoxicillin 1 gr, clarithromycin 500 mg, and metronidazole 500 mg, all twice daily for 10 days]. 8 weeks after therapy, 14C- urease breath test was performed to confirm eradication

Results: According to intention to treat analysis, the eradication rates were 87.3% [95% CI: 81.4-93.1] and 80.9% [95% CI: 74-87.8] in hybrid and concomitant groups, respectively [p=0.38]. Per-protocol eradication rates were 89.3% [95% CI: 83.8-94.7] and 83.1% [95% CI: 76.3-89.8], respectively [p=0.19]. The rates of severe side effects were not statistically different between the two groups [4% vs. 8.7%]

Conclusion: 14-day hybrid therapy can be considered as a nearly acceptable regimen with few severe side effects in Iran. However, it seems that the efficacy of this therapy is decreasing as the resistance rates to antibiotics are increasing. We suggest further studies to assess the efficacy of a more prolonged concomitant therapy for H. pylori eradication in Iran