One-week therapy with omeprazole, clarithromycin and metronidazole or ornidazole, followed by 3 weeks' treatment with omeprazole, eradicates Helicobacter pylori equally and heals duodenal ulcer

OBJECTIVE: To estimate and compare the efficacy of 'triple' 1-week regimens--omeprazole, clarithromycin and a nitroimidazole (metronidazole or ornidazole)--followed by omeprazole, for an additional 3 weeks, on Helicobacter pylori eradication and duodenal ulcer (DU) healing, in a country with a high resistance rate of H. pylori to metronidazole. DESIGN: Open, prospective, two-centre study. METHODS: Patients older than 18 years with active duodenal ulcer (DU), diagnosed by endoscopy and found to be infected with H. pylori (modified Giemsa stain and CLO test, Delta West, Australia), were included in the study. Three triple-drug regimens, given for 7 days, were used. (1) omeprazole (Om) 20 mg once a day, plus clarithromycin (Cl) 250 mg twice daily, plus ornidazole (Or) 500 mg twice daily (O1COr); (2) Om 20 mg twice daily, plus Cl 250 mg twice daily, plus Or 500 mg twice daily (OCOr); and (3) Om 20 mg twice daily, plus Cl 250 mg twice daily, plus metronidazole (M) 500 mg twice daily (OCM). Two hundred and three consecutive H. pylori-positive patients were included in the study, randomly assigned as follows: 50 patients (group A1: 32 men, 18 women, age 23-77 years) on O1COr; 47 patients (group A2: 29 men, 18 women, age 27-77 years) on OCOr; and 106 (group B: 71 men, 35 women, age 18-83 years) on OCM. Ulcer healing and H. pylori eradication were assessed endoscopically, 8-9 weeks after the start of treatment. H. pylori was considered eradicated if both histology and rapid urease test (six biopsies, antrum-body) were negative. RESULTS: Eleven patients were lost to follow-up; 192 patients were analysed. Group A1: 48; group A2: 44; group B: 100. 'Per-protocol' analysis: H. pylori eradication, 90-93% (P = 0.901); ulcer healing, 90-98% (P = 0.300). 'Intention to treat' analysis: H. pylori eradication, 85-88% (P = 0.887); ulcer healing, 86-91% (P = 0.657). Compliance was excellent, no serious side effects were observed and no patients withdrew due to side effects. CONCLUSIONS: No differences were observed in the H. pylori eradication and the healing rate among the groups. It seems that twice daily omeprazole is no better than single daily dosage and that ornidazole is as effective as metronidazole. In addition, in the studied population which is believed to have a high prevalence of metronidazole resistance, all the regimens used were effective.