Amoxicillin/metronidazole/omeprazole/clarithromycin: A new, short quadruple therapy for Helicobacter pylori eradication

Background. Triple therapy regimens including two antibiotics plus acid suppression have become the new standard therapy in Helicobacter pylori eradication because of success rates of about 90%. However, these regimens are still costly, duration is about one week or less, and side-effects are not negligible. We therefore evaluated a new quadruple therapy, because theoretically a shorter duration of treatment may result in reduced costs, fewer side-effects, and possibly in a lower potential for antibiotic resistances. Methods. Controlled, prospective pilot study including H. pylori-positive patients with gastric or duodenal ulcers or erosive gastritis, treated after failure of dual therapy (proton-pump-inhibitors or ranitidine plus amoxicillin) or for the first time. They were assigned to a one week triple standard therapy, consisting of metronidazole 400 mg bid + omeprazole 20 mg bid + clarithromycin 250 mg bid, or a newly created quadruple-regimen, which adds amoxicillin (1 g bid) to the above triple regimen. Each of the four drugs was given for 5 days. H. pylori status was checked by C-13 urea breath test before and after four weeks of therapy. Results. A total of 71 patients were treated by quadruple therapy, and 42 patients were treated by triple therapy. The eradication rate of H. pylori for patients under quadruple treatment, without vs. with previous dual therapy, were 96% vs. 92% (42/44 vs. 22/24) by per protocol and 91% vs. 88% (42/46 vs. 22/25) by intention to treat analysis (comparisons not significant). No major side-effects were reported. Conclusions. Five-day quadruple therapy (with omeprazole, metronidazole, clarithromycin and amoxicillin) represents an effective and safe new regimen for H. pylori eradication.