RESUMO
GOALS: The main goal of this study was to explore the dose-effect relationship of ilaprazole. BACKGROUND: Ilaprazole is a kind of benzimidazole proton-pump inhibitor, which was confirmed efficacious and safe in treatment of duodenal ulcer (DU). However, the dose-effect relationship of ilaprazole was not clear. STUDY: This was a double-blind, parallel, randomized study. Patients aged above 18 years with at least one endoscopically confirmed active nonmalignant DU were treated with rabeprazole 10 mg or ilaprazole 10 mg/5 mg for 4 weeks. Healing of ulcer was determined by its resolution from active to scarring stage. Symptoms relief was evaluated using a graded score. Safety and tolerability were evaluated on basis of clinical assessments. RESULTS: A total of 390 patients completed the study finally. Ulcers were successfully healed in 75.38%, 77.86%, and 83.72% of patients after 4-week treatment with rabeprazole 10 mg, ilaprazole 5 mg, and ilaprazole 10 mg, respectively. The 4-week healing rate difference between rabeprazole 10 mg and ilaprazole 5 mg was 2.48% (95% confidence interval: -7.79% to 12.74%) leading to accept the noninferiority hypothesis. Logistic regression model suggested that ilaprazole 10 mg was superior to ilaprazole 5 mg at week 2 (odds ratio, 1.92; 95% confidence interval: 1.02, 3.59; P=0.04). Most patients (80%) became asymptomatic after treatment. At the dosages administered, the 3 drug groups exhibited similar efficacy and a similar safety profile. CONCLUSIONS: Ilaprazole 5 mg is not inferior to rabeprazole 10 mg in treating DU, and a dose-effect relationship have been revealed between 5 mg and 10 mg of ilaprazole.