Esomeprazole-based Helicobacter pylori eradication therapy and the effect of antibiotic resistance: results of three US multicenter, double-blind trials.

Abstract

To determine the efficacy of once-daily esomeprazole plus antibiotics for eradication of Helicobacter pylori, to assess the effect of antibiotic resistance on eradication rate, and to define the rate of emergent resistance. Three separate randomized trials were performed in H. pylori-positive patients with a duodenal ulcer or history of documented duodenal ulcer within 5 yrs: 1) esomeprazole (40 mg once daily), amoxicillin (1 g b.i.d.), and clarithromycin (500 mg b.i.d.; this combination will be referred to as EAC) versus esomeprazole (40 mg once daily) plus clarithromycin (500 mg twice daily; this combination will be referred to as EC); 2) EAC versus esomeprazole (40 mg once daily; E); and 3) EC versus E. Therapy was given for 10 days. Endoscopy and biopsies for CLOtest, histology, and culture with susceptibility testing were done at baseline and 4 wk after completion of therapy. Per-protocol and intent-to-treat eradication rates, respectively, were as follows. For EAC versus EC in study 1 (N = 448), 84 versus 55% and 77 versus 52% (p < 0.001); for EAC versus E in study 2 (N = 98), 85 versus 5% and 78 versus 4% (p < 0.001); for EC versus E in study 3 (N = 66), 50% versus 0 and 46% versus 0 (p < 0.05). The 15% of patients in the combined studies with baseline clarithromycin resistance had significantly lower rates of eradication than those with susceptible strains (EAC: 45 vs. 89%; EC: 13 vs. 61%). Emergent resistance was less common after treatment with EAC [2/6 (33%)] than with EC (23/27 [85%]). Ten-day triple therapy with once-daily esomeprazole plus twice-daily amoxicillin and clarithromycin achieves an eradication rate virtually identical to that of the twice-daily proton pump inhibitor-based triple therapies. Baseline clarithromycin resistance, present in 15% of patients, predicts a markedly decreased rate. Use of an amoxicillin-containing regimen may decrease emergence of clarithromycin resistance.