ERADICATION OF HELICOBACTER-PYLORI BY A 1-WEEK COURSE OF FAMOTIDINE, AMOXICILLIN AND CLARITHROMYCIN

Objectives The combination of a proton pump inhibitor (PPI) such as om eprazole with amoxicillin and clarithromycin constitutes one of the mo st effective treatments for the eradication of Helicobacter pylori. Ne vertheless, the mechanisms of interaction between these drugs remain u nclear. It has been shown that minimal inhibitory concentration values of both antibiotics are considerably lower at neutral pH levels than in an acid environment. Further, omeprazole possesses bacteriostatic a ctivity. To evaluate the significance of these mechanisms we replaced omeprazole with famotidine, a drug which only suppresses acid producti on, but has no intrinsic antimicrobial activity. Methods We evaluated the efficacy of a 1-week course of famotidine 80 mg b.i.d., amoxicilli n 1000 mg b.i.d. and clarithromycin 500 mg b.i.d. in a pilot study (20 patients), and then confirmed our results in a larger replication stu dy (87 patients). A total of 107 patients with H. pylori-associated du odenal ulcer (n = 54), gastric ulcer (n = 14) or non-ulcer dyspepsia ( n = 39) were included. Endoscopy was performed at baseline and 4-6 wee ks after discontinuation of treatment. H. pylori status was assessed b y the urease test and histology. Results H. pylori was successfully er adicated in 94 of 104 patients who completed the study (90.4%; Cl 95%, 83.0-95.3%). By intention-to-treat analysis, the eradication rate was 87.9% (Cl 95%, 80.1-93.4%). Ulcer healing was observed in 98.1% of du odenal ulcers and 92.9% of gastric ulcers (based on per-protocol analy sis). Mild side effects that did not require termination of treatment were reported by seven patients (6.7%). Conclusion A 1-week course of famotidine, amoxicillin and clarithromycin is a highly effective, simp le and safe eradication regimen. Our data indicate that acid suppressi on is the crucial mechanism by which the activity of amoxicillin and c larithromycin against H. pylori is enhanced, whereas additional antimi crobial activity or other specific effects of PPIs seem to be less imp ortant. (C) 1998 Lippincott-Raven Publishers.