Effect and safety of anaprazole in the treatment of duodenal ulcers: a randomized, rabeprazole-controlled, phase III non-inferiority study

BACKGROUND

The pharmacokinetic and clinical behaviors of many proton pump inhibitors (PPIs) in peptic ulcer treatment are altered by CYP2C19 genetic polymorphisms. This non-inferiority study evaluated the efficacy and safety of the novel PPI anaprazole compared with rabeprazole. We also explored the influence of Helicobacter pylori ( H. pylori ) infection status and CYP2C19 polymorphism on anaprazole.

METHODS

In this multicenter, randomized, double-blind, double-dummy, positive-drug parallel-controlled, phase III study, Chinese patients with duodenal ulcers were randomized 1:1 to receive rabeprazole 10 mg + anaprazole placebo or rabeprazole placebo + anaprazole 20 mg once daily for 4 weeks. The primary efficacy endpoint was the 4-week ulcer healing rate assessed by blinded independent review. Secondary endpoints were the proportion of patients with improved overall and individual duodenal ulcer symptoms at 4 weeks. Furthermore, exploratory subgroup analysis of the primary endpoint by H. pylori status and CYP2C19 polymorphism was conducted. Adverse events were monitored for safety. Non-inferiority analysis was conducted for the primary endpoint.

RESULTS

The study enrolled 448 patients (anaprazole, n = 225; rabeprazole, n = 223). The 4-week healing rates were 90.9% and 93.7% for anaprazole and rabeprazole, respectively (difference, -2.8% [95% confidence interval, -7.7%, 2.2%]), demonstrating non-inferiority of anaprazole to rabeprazole. Overall duodenal ulcer symptoms improved in 90.9% and 92.5% of patients, respectively. Improvement rates of individual symptoms were similar between the groups. Healing rates did not significantly differ by H. pylori status or CYP2C19 genotype for either treatment group. The incidence of treatment-emergent adverse events was similar for anaprazole (72/220, 32.7%) and rabeprazole (84/219, 38.4%).

CONCLUSIONS

The efficacy of anaprazole is non-inferior to that of rabeprazole in Chinese patients with duodenal ulcers.

REGISTRATION

ClinicalTrials.gov, NCT04215653.

Rabeprazole in Patients With Duodenal Ulcers: A Randomized Double-Blinded Multicenter Phase II Clinical Trial

Background: Proton pump inhibitors (PPIs) are validated gastric acid suppressors and have been widely used to treat patients with active duodenal ulcers. Although existing PPIs have shown great efficacy, many scientists are still devoted to developing more effective PPIs with better safety profile. Herein, we aimed to compare the safety and efficacy of anaprazole in duodenal mucosal healing, a novel PPI, to that of rabeprazole.

Methods: In this multicenter, randomized, positive-controlled, double-blinded, parallel-group phase II clinical trial, a total of 150 qualified patients with endoscopically confirmed active duodenal ulcers were randomized (1:1:1) to receive rabeprazole 10 mg, anaprazole 20 mg or anaprazole 40 mg for 4 weeks. The ulcer healing rates after 4 weeks of treatment were compared between groups by independent central review and investigator review. In addition, symptoms and safety were evaluated.

Results: Based on the independent central review, the ulcer healing rates of the 10 mg rabeprazole, 20 mg anaprazole and 40 mg anaprazole groups were 88.0, 85.1, and 87.5%, respectively, in the FAS population and 88.9, 86.0, and 90.9%, respectively, in the PPS population. The ulcer healing rate difference between anaprazole 20 mg and Rabeprazole 10 mg is −2.9% (95% CI, −16.5–10.7%), and −0.5% (95% CI, −13.5–12.5%) between anaprazole 40 mg and Rabeprazole 10 mg, in the FAS population. Based on the investigator review, the ulcer healing rates of the 10 mg rabeprazole, 20 mg anaprazole, and 40 mg anaprazole groups were 72.0, 70.2, and 77.1%, respectively, in the FAS population and 75.6, 72.1, and 79.5%, respectively, in the PPS population. The ulcer healing rate difference between anaprazole 20 mg and Rabeprazole 10 mg is −1.8% (95% CI, −19.8–16.3%), and 5.1% (95% CI, −12.2–22.3%) between anaprazole 40 mg and Rabeprazole 10 mg, in the FAS population. Most patients (>90%) eventually achieved complete symptom relief. The incidence rates of adverse events were of no significant differences among the treatment groups. Potential possible better liver tolerance was observed in two anaprazole dose groups than rabeprazole 10 mg group.

Conclusion: Both at a dosage of 20 and 40 mg daily, anaprazole, is effective with good safety profile in the treatment of active duodenal ulcers in this Phase 2 study, which allows anaprazole to be advanced to a phase III clinical trial.

Clinical Trial Registration:https://www.clinicaltrials.gov/ct2/results?cond=&term=NCT04503629&cntry=&state=&city=&dist=, Identifier: CTR20181464, NCT04503629.