Background: Eradication regimens combining two antibiotics with a proton pump inhibitor have been studied intensively. In contrast, only a few studies have focused on the possible role of H2-receptor antagonists in eradication therapy. The mechanism involved in the synergy between antibiotics and proton pump inhibitors is still controversial.
Objectives: To compare the results of two triple-therapy regimens, different only in the antisecretory drugs used, in patients with Helicobacter pylori infection, and to assess the impact of primary resistance to metronidazole on treatment outcome.
Methods: A total of 120 patients with peptic ulcer and non-ulcer dyspepsia were randomly assigned to a 2-week course of either: famotidine 40 mg twice a day, amoxycillin 1 g twice a day and tinidazole 500 mg twice a day (FAT group; n = 60); or omeprazole 20 mg twice a day, amoxycillin 1 g twice a day and tinidazole 500 mg twice a day (OAT group; n = 60). Upper endoscopy was performed prior to treatment and at least 4 weeks after completion of treatment and discontinuation of the antisecretory therapy. H. pylori status was assessed by a biopsy urease test, histology and culture.
Results: In the intention-to-treat analysis, eradication of H. pylori was achieved in 48 of the 60 patients (80%; 95% confidence interval: 70-90%) in the FAT group, compared to 50 of the 60 patients (83.3%; 95% confidence interval: 74-93%) in the OAT group. In the per protocol analysis, eradication therapy was achieved in 48 out of 53 patients (90.6%; 95% confidence interval: 83-98%) treated with FAT and 50 out of 57 patients (87.7%; 95% confidence interval: 79-96%) treated with OAT (not significant). The primary metronidazole resistance was present in 28.8% of strains. Overall, per protocol eradication rates in strains resistant and susceptible to metronidazole were 83.3% and 91.3% respectively (P > 0.05).
Conclusions: Two-week courses of either high-dose famotidine or omeprazole, both combined with amoxycillin and tinidazole, are equally effective for eradication of H. pylori infection. In a 2-week triple therapy, metronidazole resistance has no significant impact on eradication rates.