High‐dose rabeprazole–amoxicillin versus rabeprazole–amoxicillin–metronidazole as second‐line treatment after failure of the Japanese standard regimen for Helicobacter pylori infection

Summary Background : There is currently no optimal second‐line treatment after failure of Helicobacter pylori triple therapy. Aim : To determine effective salvage therapy after failure of lansoprazole–amoxicillin–clarithromycin. Methods : After failure of lansoprazole–amoxicillin–clarithromycin 123 out‐patients were randomized to receive either 2‐week rabeprazole (20 mg b.d.) + amoxicillin (1000 mg b.d.) (RA group) or 1‐week rabeprazole (10 mg b.d.) + amoxicillin (750 mg twice b.d.) + metronidazole (250 mg b.d.) (RAM group). Eradication was assessed by the 13C‐urea breath test. We also evaluated cytochrome p450 (CYP) 2C19 genotype status, determined by polymerase chain reaction – restriction fragment length polymorphism, and susceptibility to clarithromycin and metronidazole. Results : On an intention‐to‐treat basis, H. pylori infection cure was achieved in 37 of 63 (59%) patients in the RA group and in 49 of 60 (82%) patients in the RAM group. Per protocol‐based eradication rates in the RA and RAM groups were 66% (37/56) and 88% (49/56), respectively. In both analytic sets there were significant differences between the treatment groups (P