Beta-lactamase inhibition with clavulanic acid supplementing standard amoxycillin-based triple therapy does not increase Helicobacter pylori eradication rate.

BACKGROUND: Antibiotic resistance is the main reason of failure for H. pylori eradication and beta-lactamases produced by resistant H. pylori strains is a possible mechanism underlying ineffectiveness of an amoxycillin-based triple therapy. AIM: To investigate the benefit of using clavulanic acid associated with amoxycillin compared with amoxycillin alone in a standard triple therapy. METHODS: A total 172 H. pylori-positive dyspeptic patients were randomised to a daily treatment with esomeprazole (20 mg bid), clarithromycin (500 mg bid) and either amoxycillin plus clavulanic acid (1 g bid) or amoxycillin (1 g bid) alone for 1 week. H. pylori status was defined by histology and urea breath test at entry and following 8 weeks from the end of therapy by urea breath test and antigen faecal assessment. RESULTS: At intention-to-treat and per-protocol analysis eradication rates achieved by amoxycillin plus clavulanic acid (72 and 78%) were higher, but not significantly, than those achieved by amoxycillin alone triple therapy (62 and 72%). Compliance was good, side-effects mild and with a similar incidence in both regimens. CONCLUSIONS: Clavulanic acid supplemented to amoxycillin-based standard triple therapy does not significantly increase the H. pylori eradication rate with standard triple therapy.