Objective: The new proton pump inhibitor (PPI), ilaprazole performed better at the dose of 10 mg/d relative to 5 or 20 mg/d in a previous phase II trial. A larger phase III trial was carried out to confirm the efficacy and safety of ilaprazole (10 mg/d) compared with omeprazole (20 mg/d) and provide some characteristics of the relationship between ilaprazole metabolism and CYP2C19 for later studies.
Research design and methods: Patients with at least one endoscopically diagnosed active duodenal ulcer (DU) were enrolled in a multicenter, randomized, double-blind, positive controlled trial and then assigned randomly to the ilaprazole group (10 mg/d) or the omeprazole group (20 mg/d) with a sample allocation ratio 2:1. The course of treatment was 4 weeks.
Clinical trial registration: ClinicalTrials.gov registration number: NCT00952978.
Main outcome measures: The primary endpoint was endoscopically diagnosed ulcer healing rate at week 4. Symptom relief was evaluated as a secondary endpoint by graded scores. Safety and tolerability were evaluated on basis of clinical assessments. In addition, blood samples were collected at baseline for CYP2C19 genotypes identification.
Results: Efficacy analyses were based on 494 patients. At week 4, the ulcer healing rates were 93.0% in ilaprazole group and 90.8% in omeprazole group (rate difference: 2.2%; 95% confidence interval: -2.8% to 7.2%). No obvious variation of healing rate on different CYP2C19 genotypes was found in ilaprazole group. The majority of patients (>80%) became asymptomatic after treatment. Incidences of adverse drug reactions were similar between ilaprazole group and omeprazole group (8.5% vs. 11.5%).
Conclusions: Ilaprazole (10 mg/d) is as effective as omeprazole (20 mg/d) in the treatment of DU with similar side effects. The efficacy of ilaprazole is not affected by CYP2C19 polymorphisms.