Twice-daily versus thrice-daily clarithromycin in combination with ranitidine bismuth citrate in the eradication of Helicobacter pylori

Background. Ranitidine bismuth citrate (RBC), 400 mg bid for 4 weeks, plus clarithromycin, 500 mg tid, is a regimen approved by the US Food and Drug Administration for the eradication of Helicobacter pylori in patients with duodenal ulcers. Proof that the clarithromycin portion of the regimen could be given twice daily without loss of efficacy would reduce cost and improve patient compliance. The objective of this study was to compare the H. pylori eradication rates in patients who had duodenal ulcer and were randomly assigned to 4 weeks of treatment with RBC, 400 mg bid, in conjunction with 2 weeks of therapy with either clarithromycin, 500 mg tid, or clarithromycin, 500 mg bid. Patients and Methods. Patients who had a duodenal ulcer and were H, pylori-positive by at least two tests were randomly assigned to (1) RBC, 400 mg bid for 4 weeks, plus clarithromycin, 500 mg tid for 2 weeks, or (2) RBC, 400 mg bid for 4 weeks, plus clarithromycin, 500 mg bid for 2 weeks. H. pylori eradication was assessed 4 weeks after completion of RBC plus clarithromycin. Results. Three hundred eighty-three patients from 78 centers had a duodenal ulcer and were H, pylori-positive, The modified intent-to-treat (MITT) and the per-protocol (PP) eradication rates were statistically equivalent between the twice-daily (65% MITT, 74% PP) and thrice-daily (63% MITT, 73% PP) clarithromycin treatment regimens. Incidence and types of adverse events did not differ between the two groups. Conclusions. For eradicating H. pylori in patients with duodenal ulcer, clarithromycin, 500 mg bid for 2 weeks, with RBC, 400 mg bid for 4 weeks, is equivalent to clarithromycin, 500 mg tid with RBC. The potential enhancement of patient compliance, reduced cost of clarithromycin, and equivalent efficacy would support the use of twice-daily clarithromycin in triple-therapy regimens with RBC.