Efficacy and tolerability of ranitidine bismuth citrate plus amoxycillin and clarithromycin as first- or second-line therapy to cure Helicobacter pylori infection.

Background/aims: Ranitidine bismuth citrate has recently been introduced for the treatment of H. pylori infection and obtains good eradication rates; however, eradication failures still appear in a considerable proportion of cases. The aim of this study was to compare the efficacy and tolerability of ranitidine bismuth citrate plus amoxycillin and clarithromycin as first- or second-line therapy to cure H. pylori infection.

Methodology: We studied 423 consecutive H. pylori-positive patients. In 210 consecutive patients H. pylori infection was diagnosed for the first time (group A), while 213 consecutive patients were enrolled after failure of a first attempt to eradicate H. pylori (group B). All patients received ranitidine bismuth citrate 400 mg b.d. plus clarithromycin 500 mg b.d. and amoxycillin 1 g b.d. for seven days. H. pylori-status was evaluated by means of histology and rapid urease test at entry and by 13C-urea breath test in all patients one month after treatment.

Results: 410/423 patients completed the study (202/210 in group A and 208/213 in group B). Two patients of group A and 1 patient of group B were withdrawn from the study due to poor compliance, 6 group A patients and 4 group B patients were lost to follow-up. In group A, after the end of treatment, 181/202 patients were H. pylori-negative (per-protocol analysis: 89.60% [C.I. 95%: 82-95%]; on intention-to-treat analysis: 86.19% [C.I. 95%; 76-92%]), side-effects occurred in 29 patients (13.80%); they were severe in 2 patients and the patients were withdrawn from the study. In group B, after the end of treatment, 200/208 patients were H. pylori-negative (per-protocol analysis: 95.15% [C.I. 95%; 92-100%], on intention-to-treat analysis: 93.89% [C.I. 95%; 89-98%), side-effects occurred in 11 patients (5.13%); they were slight or mild and did not require discontinuation of the treatment. The results of group B were statistically better than group A, both in eradication rate (P < 0.01) as well as both side-effects provoked (P < 0.01).

Conclusions: Ranitidine bismuth citrate-clarithromycin-amoxycillin is more effective when used as second-line therapy rather than when used as first-line therapy; second, ranitidine bismuth citrate-clarithromycin-amoxycillin shows lower and slighter side-effects when used as second-line therapy rather than when used as first-line therapy; finally, the excellent tolerability of ranitidine bismuth citrate + clarithromycin + amoxycillin influences positively the patients' compliance, both as first- and second-line therapy.