Rifaximin suspension for the eradication of Helicobacter pylori

Abstract The in vitro sensitivity of Helicobacter pylori to rifaximin, a new rifamycin antibiotic, was evaluated in 40 clinical isolates by the agar dilution method. Rifaximin showed good activity, with a 50% minimum inhibitory concentration of 4 mg/L −1 . Consequently, we assessed rifaximin in H pylori —positive patients. Overall, 71 patients with upper gastrointestinal symptoms (35 men and 36 women; aged 19 to 73 years, mean, 45.6 years) were found to have H pylori —associated gastritis. The first 30 consecutive patients received monotherapy with rifaximin 600 mg three times a day (TID) for 14 days. The 41 patients enrolled thereafter were allocated in an open, randomized fashion to four different treatment groups for 14 days: (1) rifaximin 600 mg TID and colloidal bismuth subcitrate 240 mg twice a day (BID) (n = 10); (2) rifaximin 600 mg TID and omeprazole 20 mg BID (n = 10); (3) rifaximin 600 mg TID and amoxicillin 1 g BID (n = 10); or (4) rifaximin 1800 mg TID and metronidazole 500 mg TID (n = 11). Upper gastrointestinal symptoms (pyrosis, bloating, epigastric pain, and nausea) were recorded and assessed before and 4 weeks after treatment. Patients were assessed by endoscopy, histology, CP test, culture, and serology (immunoglobulin G [IgG] to H pylori ) at entry. Sixty-seven patients were available for follow-up 4 weeks after the completion of treatment. A statistically significant improvement in symptoms was seen in patients treated with rifaximin and rifaximin plus colloidal bismuth subcitrate. No statistically significant differences in degree of improvement in endoscopic and histologic findings were seen among the five treatment groups. A statistically significant decrease in the mean IgG value after treatment was found for rifaximin, rifaximin plus colloidal bismuth subcitrate, and rifaximin plus omeprazole. The overall eradication rate was 43%. These results suggest that rifaximin may be an effective antibiotic against H pylori infection and is worthy of further study.