Vonoprazan prevents ulcer recurrence during long-term NSAID therapy: randomised, lansoprazole-controlled non-inferiority and single-blind extension study

Randomised trial of acid inhibition by vonoprazan 10/20 mg once daily vs rabeprazole 10/20 mg twice daily in healthy Japanese volunteers (SAMURAI pH study)

BACKGROUND

Vonoprazan (V), a potassium-competitive acid blocker, has a more durable acid-inhibitory effect as compared with standard-dose proton pump inhibitors (PPIs) but has not been compared with 2-4 times higher daily PPI doses administered in two divided doses.

AIMS

To evaluate the acid-inhibitory effect of V 10/20 mg once-daily (OD; V10/V20) vs rabeprazole (R) 10/20 mg twice-daily (BID; R20/R40) in healthy Japanese volunteers.

METHODS

This multicentre, randomised, open-label, two-period, crossover study compared V10 or V20 vs R20, or V20 vs R40 using three cohorts of 10 healthy Japanese adults. Within each cohort, subjects were randomised to receive V or R for 7 days and, following a washout period ≥7 days, the other treatment for 7 days. On day 6 of each period, 24-hours multichannel gastric impedance-pH monitoring was performed. Percent times pH ≥ 3, ≥4 and ≥5 (pH 3, 4 and 5 holding time ratios [HTRs]) in 24 hours were evaluated as primary pharmacodynamic endpoints.

RESULTS

Acid-inhibitory effect (24-hours pH 3 HTR) of V20 was greater than those of R20 (91.0% vs 65.3%; P = .0049) and R40 (98.5% vs 85.9%; P = .0073). Similar results were obtained for 24-hours pH 4 and 5 HTRs. V20 also achieved greater nocturnal pH 4 (91.5% vs 73.2%; P = .0319) and 5 HTRs (78.8% vs 62.2%; P = .0325) as compared with R40. One subject (20%) developed diarrhoea while receiving R40 which was considered treatment-related.

CONCLUSIONS

Compared with 2-4 times the standard daily dose of R, V20 exerts a more potent and durable acid-inhibitory effect. Trial identifier: UMIN000022198 (www.umin.ac.jp/ctr/index.htm).

Cytochrome P450-Based Drug-Drug Interactions of Vonoprazan In Vitro and In Vivo

Background

Vonoprazan fumarate is a potassium-competitive acid blocker that was developed as a novel acid-suppressing drug for multiple indications. As a potential alternative to proton-pump inhibitors, the determination of the drug-drug interactions is vital for further applications. Probe drug cocktails are a type of rapid, economical, and efficient approach for evaluating cytochrome P450 enzyme activities. Since vonoprazan is metabolized partly by cytochrome P450, cocktails were used to study CYP-based drug-drug interactions.

Methods

This study was conducted both in vitro and in vivo. In the in vitro study of rat liver microsomes, ultra-performance liquid chromatography coupled to tandem mass spectrometry was utilized to assess the reversible inhibition of cytochrome P450 by vonoprazan by determining the concentration of probe drugs (phenacetin, bupropion, tolbutamide, dextromethorphan, midazolam, chlorzoxazone). The differences in the levels of probe drugs between the rat groups with or without vonoprazan administration were also tested in the rats.

Results

In vitro analysis revealed that the IC₅₀ values of midazolam, tolbutamide, dextromethorphan, and bupropion in rat microsomes were 22.48, 18.34, 3.62, and 3.68 μM, respectively, while chlorzoxazone and phenacetin displayed no inhibition. In vivo analysis revealed that midazolam, bupropion, dextromethorphan, and tolbutamide showed significant (P < 0.05) differences in distinct pharmacokinetic parameters after vonoprazan administration, while those of chlorzoxazone and phenacetin were not significantly different.

Conclusion

The in vitro and in vivo results indicated that vonoprazan can inhibit CYP3A4, CYP2C9, CYP2D6, and CYP2B6, suggesting that the coadministration of vonoprazan with cytochrome P450 substrates should be performed cautiously in clinical settings.

Phase III, randomised, double-blind, multicentre study to evaluate the efficacy and safety of vonoprazan compared with lansoprazole in Asian patients with erosive oesophagitis

OBJECTIVE

To establish the non-inferior efficacy of vonoprazan versus lansoprazole in the treatment of Asian patients with erosive oesophagitis (EO).

DESIGN

In this phase III, double-blind, multicentre study, patients with endoscopically confirmed EO were randomised 1:1 to receive vonoprazan 20 mg or lansoprazole 30 mg, once daily for up to 8 weeks. The primary endpoint was EO healing rate at 8 weeks. The secondary endpoints were EO healing rates at 2 and 4 weeks. Safety endpoints included treatment-emergent adverse events (TEAEs).

RESULTS

In the vonoprazan (n=238) and lansoprazole (n=230) arms, 8-week EO healing rates were 92.4% and 91.3%, respectively (difference 1.1% (95% CI -3.822% to 6.087%)). The respective 2-week EO healing rates were 75.0% and 67.8% (difference 7.2% (95% CI -1.054% to 15.371%)), and the respective 4-week EO healing rates were 85.3% and 83.5% (difference 1.8% (95% CI -4.763% to 8.395%)). In patients with baseline Los Angeles classification grade C/D, 2-week, 4-week and 8-week EO healing rates were higher with vonoprazan versus lansoprazole (2 weeks: 62.2% vs 51.5%, difference 10.6% (95% CI -5.708% to 27.002%); 4 weeks: 73.3% vs 67.2%, difference 6.2% (95% CI -8.884 to 21.223); and 8 weeks: 84.0% vs 80.6%, difference 3.4% (95% CI -9.187% to 15.993%)). Overall, EO healing rates appeared higher with vonoprazan versus lansoprazole. TEAE rates were 38.1% and 36.6% in the vonoprazan and lansoprazole group, respectively.

CONCLUSION

Our findings demonstrate the non-inferior efficacy of vonoprazan versus lansoprazole in terms of EO healing rate at 8 weeks in this population. Safety outcomes were similar in the two treatment arms.

TRIAL REGISTRATION NUMBER

NCT02388724.

Current states of prevention of drug-induced gastroduodenal ulcer in real clinical practice: a cross-sectional study

Non-steroidal anti-inflammatory drugs (NSAIDs) or low-dose aspirin (LDA) are the most common causes of drug-induced gastroduodenal ulcer and We investigated preventive treatment with use of concomitant anti-ulcer drugs and the clinical features of gastroduodenal ulcer in cases treated with these drugs. Patients with gastroduodenal ulcer and patients with bleeding were classified into 3 groups: LDA, non-aspirin NSAIDs, and those taking neither aspirin nor NSAIDs. Chronological changes over the past 16 years (1st-5th period) were investigated. The status of prevention of ulcer and clinical features were examined. From January 2002 to December 2018, the ratio of all patients taking NSAIDs and LDA increased significantly until 3rd period (p<0.05), but then started to decrease in 4th period; and the percentage of all patients taking NSAIDs and LDA decreased significantly (p<0.05) until 5th period. Among the 292 patients with gastroduodenal ulcer and the 121 patients with a bleeding ulcer taking NSAIDs and LDA, 16 (5.5%) and 9 (7.4%), respectively, were receiving preventive treatment with concomitant anti-ulcer drugs. The percentages of patients taking LDA and other antiplatelet drugs in patients with bleeding gastroduodenal ulcer were significantly higher than those in patients with non-bleeding. In conclusion, although the percentages of patients with gastroduodenal ulcer taking NSAIDs or LDA have not recently increased in real-world practice, preventive treatment in these patients is still low. This low rate of prevention suggests the need to enlighten physicians about preventive treatment because drug withdrawal of LDA has a high risk of cardiovasculr and cerebrovascular events.

Changes of gastric ulcer bleeding in the metropolitan area of Japan

BACKGROUND

The two main causes of gastric ulcer bleeding are Helicobacter pylori (H. pylori) infection and ulcerogenic medicines, although the number of cases caused by each may vary with age. In Japan, the rate of H. pylori infection has fallen over the last decade and the number of prescriptions for non-steroidal anti-inflammatory drugs (NSAIDs) and antithrombotic drugs is increasing as the population ages. Methods of treatment for gastric ulcer bleeding have advanced with the advent of hemostatic forceps and potassium-competitive acid blocker (P-CAB). Thus, causes and treatments for gastric ulcer bleeding have changed over the last decade.

AIM

To examine the trends of gastric ulcer bleeding over 10 years in the metropolitan area of Japan.

METHODS

This is a single-center retrospective study. A total of 564 patients were enrolled from inpatients admitted to our hospital with gastric ulcer bleeding between 2006 and 2016. Age, medication history, H. pylori infection, method of treatment, rate of rebleeding, and the length of hospitalization were analyzed. Factors associated with gastric ulcer bleeding were evaluated using Fisher's exact test, Pearson's Chi-squared test or Student's t-test as appropriate. The Jonckheere-Terpstra test was used to evaluate trends. A per-protocol analysis was used to examine the rate of H. pylori infection.

RESULTS

There was a significant increase in the mean age over time (P < 0.01). The rate of H. pylori infection tended to decrease over the study period (P = 0.10), whereas the proportion of patients taking antithrombotic agents or NSAIDs tended to increase (P = 0.07). Over time, the use of NSAIDs and antithrombotic drugs increased with age. By contrast, the rate of H. pylori infection during the study period fell with age. H. pylori-induced ulcers accounted for the majority of cases in younger patients (< 70 years old); however, the rate decreased with age (P < 0.01). The method of treatment trend has changed significantly over time. The main method of endoscopic hemostasis has changed from clipping and injection to forceps coagulation (P < 0.01), and frequently prescribed medicines have changed from proton pump inhibitor to P-CAB (P < 0.01). The rate of rebleeding during the latter half of the study was significantly lower than that in the first half.

CONCLUSION

These trends, gastric ulcers caused by ulcerogenic drugs were increasing with age and H. pylori-induced ulcers were more common in younger patients, were observed.

Efficacy and Safety of Vonoprazan in Patients With Nonerosive Gastroesophageal Reflux Disease: A Randomized, Placebo-Controlled, Phase 3 Study

OBJECTIVES

To assess the efficacy and safety of vonoprazan on heartburn symptoms in patients with nonerosive reflux disease (NERD) (ClinicalTrials.gov: NCT02954848).

METHODS

This phase 3, double-blind, placebo-controlled study included Japanese patients aged 20 years and older with grade N/M NERD and recurrent heartburn. Patients received placebo (n = 245) or vonoprazan 10 mg (n = 238) for 4 weeks. The primary efficacy outcome was frequency of heartburn experienced by patients during the treatment period (proportion of days without heartburn). Other outcomes included cumulative improvement rates of heartburn, proportion of patients with complete heartburn resolution in the fourth week of treatment, and safety.

RESULTS

Compared with placebo, the proportion of days without heartburn was not significantly higher in the vonoprazan group in the full analysis (primary end point, 72.55% vs 61.50%, vonoprazan vs placebo, P = 0.0643) but was significantly higher in the per-protocol-set sensitivity analysis (P = 0.0341). Early onset of response and significantly greater cumulative improvement rates of heartburn were observed in the vonoprazan group (P = 0.0003). In a post hoc analysis, a greater proportion of patients with complete heartburn resolution in the fourth week of treatment were reported in the vonoprazan group (P = 0.0023). Incidence of treatment-emergent adverse events was similar between treatment groups (23.5% vs 23.3%); most treatment-emergent adverse events were mild in severity.

DISCUSSION

Although vonoprazan 10 mg was not superior to placebo with respect to proportion of days without heartburn in Japanese patients with NERD, vonoprazan had a significantly higher cumulative rate of heartburn resolution and was well tolerated.

The efficacy of vonoprazan for management of post-endoscopic submucosal dissection ulcers compared with proton pump inhibitors: A meta-analysis

OBJECTIVE

Artificial ulcers after endoscopic submucosal dissection (ESD) are usually treated by proton pump inhibitors (PPIs) in clinical setting. Vonoprazan, a newly developed potassium-competitive acid blocker, has recently been used to treat post-ESD ulcers. We aimed to evaluate the efficacy and safety of vonoprazan on the healing of post-ESD artificial ulcers compared with those of proton pump inhibitors (PPIs) using a meta-analysis.

METHODS

EMBASE, MEDLINE, Scopus and Cochrane Library databases were searched for all studies comparing the efficacy and safety of vonoprazan with those of PPIs in the treatment of post-ESD ulcers.

RESULTS

Fourteen articles with 1328 patients were included in this meta-analysis. When comparing ulcer shrinkage rate, vonoprazan showed a better efficacy than PPIs (mean difference 0.56, 95% confidence interval [CI] 0.18-0.93). Vonoprazan also led to a higher scar formation rate (odds ratio [OR] 1.58, 95% CI 1.00-2.47) and showed a potential superiority on reducing the risk of post-ESD bleeding compared with PPIs, with a pooled OR of 0.69, although there was no statistically significant difference.

CONCLUSIONS

Compared with PPIs, vonoprazan showed a better efficacy in ulcer shrinkage rate and achieved more complete healing in the treatment of post-ESD ulcers. Vonoprazan did not induce any incremental risk of post-ESD bleeding as well. It may be an appropriate choice in the management of artificial ulcers after ESD.

Management of gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) continues to be one of the most prevalent gastrointestinal tract disorders. Management of GERD is individualized for each patient depending on severity of symptoms, complications of GERD and patient/physician preference. The different management options include life style modification, pharmacological therapy, minimally invasive procedures and surgery. The final decision regarding management should be made based on an individualized patient centered approach on a case-by-case basis in consultation with a multidisciplinary team including primary care physician, gastroenterologist and surgeon. We provide a comprehensive review for the management of GERD.

Peptic Ulcer Disease: A Brief Review of Conventional Therapy and Herbal Treatment Options

Peptic ulcer is a chronic disease affecting up to 10% of the world's population. The formation of peptic ulcers depends on the presence of gastric juice pH and the decrease in mucosal defenses. Non-steroidal anti-inflammatory drugs (NSAIDs) and Helicobacter pylori (H. pylori) infection are the two major factors disrupting the mucosal resistance to injury. Conventional treatments of peptic ulcers, such as proton pump inhibitors (PPIs) and histamine-2 (H2) receptor antagonists, have demonstrated adverse effects, relapses, and various drug interactions. On the other hand, medicinal plants and their chemical compounds are useful in the prevention and treatment of numerous diseases. Hence, this review presents common medicinal plants that may be used for the treatment or prevention of peptic ulcers.

Role of Acid Suppression in Acid-related Diseases: Proton Pump Inhibitor and Potassium-competitive Acid Blocker

Proton pump inhibitors are commonly utilized for the treatment of gastric acid-related diseases, such as gastroesophageal reflux disease, peptic ulcer disease, and Helicobacter pylori infection, and for the prevention of low-dose aspirin or nonsteroidal anti-inflammatory drug-induced peptic ulcers. Vonoprazan is a first-in-class potassium-competitive acid blocker, which has distinct advantages compared to other conventional proton pump inhibitors in terms of the efficacy for acid suppression. Due to its strong gastric acid suppression capabilities, vonoprazan serves as an effective drug for the treatment of gastroesophageal reflux disease and H. pylori infection.

Short-Term Symptomatic Relief in Gastroesophageal Reflux Disease: A Comparative Study of Esomeprazole and Vonoprazan

BACKGROUND AND AIM

Proton pump inhibitors and vonoprazan (a potassium-competitive acid blocker) are recommended as first-line treatments for gastroesophageal reflux disease (GERD). However, few reports have investigated the onset of action of these agents for GERD symptom relief. The present study compared the symptom relief of esomeprazole with that of vonoprazan via monitoring self-reported GERD symptoms after treatment initiation.

METHODS

This was a prospective, multicenter, randomized, open-label, parallel group, comparative clinical study between esomeprazole (20 mg/day) and vonoprazan (20 mg/day) administered for 4 weeks to patients with GERD symptoms. Patients who had scores ≥ 8 on the Gastroesophageal Reflux Disease Questionnaire (GerdQ) were defined as having GERD and enrolled in this study. Sixty patients were randomly assigned to either the esomeprazole group (n = 30) or the vonoprazan group (n = 30). Treatment response rates in each drug group were evaluated according to the GerdQ. The Frequency Scale for the Symptoms of GERD (FSSG) scores from the 1st day after treatment initiation and the Global Overall Symptom (GOS) scale scores during treatment were also evaluated.

RESULTS

At 4 weeks, the treatment response rates for symptom relief according to the GerdQ were 88.0% in the esomeprazole group and 81.8% in the vonoprazan group. The GOS scales, which reflect the impact of GERD symptoms, were similar for both groups. The FSSG scores decreased from the 1st to the 14th day in both groups.

CONCLUSIONS

There were no substantial differences in the symptom relief between the two groups at any time point in this short-term study.

Potassium-competitive acid blockers - are they the next generation of proton pump inhibitors?

The modern lifestyle caters to an increase in the incidence of peptic ulcer disease, gastroesophageal reflux disease and several other acid-related conditions of the gut. The drugs to prevent these conditions work either through H2 receptor blockade or inhibition of the H⁺, K⁺ ATPase enzyme. Although proton pump inhibitors have been proven to be efficacious, they have a slow onset of action with limited resolution of symptoms in most patients. Potassium-competitive acid blockers (P-CABs) are novel drugs that bind reversibly to K⁺ ions and block the H⁺, K⁺ ATPase enzyme, thus preventing acid production. P-CABs have a fast onset of action and have dose-dependent effects on acid production. Animal studies exist that differentiate the better results of P-CABs from proton pump inhibitors; further human trials will give a comprehensive picture of the results and will help to elucidate the therapeutic benefits of this new group of drugs.

A case-control study of the risk of upper gastrointestinal mucosal injuries in patients prescribed concurrent NSAIDs and antithrombotic drugs based on data from the Japanese national claims database of 13 million accumulated patients

BACKGROUND

We aimed to identify the adverse effects of nonsteroidal anti-inflammatory drugs (NSAIDs) and antithrombotics on the upper gastrointestinal (GI) mucosa in a clinical setting as a case-control study using a large-scale medical database in Japan.

METHODS

We evaluated the risk of upper GI mucosal injuries in patients receiving NSAIDs and antithrombotics using the Japan Medical Data Center claims database with data for 13 million accumulated patients, from January 2009 to December 2014. Endoscopically evaluated upper GI mucosal injuries were peptic ulcers (n = 143,271), upper GI bleeding (n = 10,545), and gastroesophageal reflux disease (n = 154,755). For each patient, ten controls were matched by age, sex, and diagnosis month.

RESULTS

The odds ratio (OR) for peptic ulcers was 1.45, 1.31, 1.50, 1.53, and 1.62; for upper GI bleeding: 1.76, 1.62, 1.96, 1.82, and 2.38; and for gastroesophageal reflux disease: 1.54, 1.41, 1.89, 1.67, and 1.91 for NSAIDs, COX-2 selective inhibitors, low-dose aspirin, antiplatelet drugs, and anticoagulants, respectively (all statistically significant: P < 0.001). Polypharmacy with NSAIDs and antithrombotic drugs increased the risk of upper GI injuries compared with single-drug therapy. The injury risk was also increased by lifestyle-related diseases, including diabetes mellitus and hyperlipidemia.

CONCLUSIONS

This case-control study using the large organized Japanese claims database provided the risk of upper GI mucosal injuries in patients receiving NSAIDs and antithrombotic drugs.

Potent Potassium-competitive Acid Blockers: A New Era for the Treatment of Acid-related Diseases

Conventional proton pump inhibitors (PPIs) are used as a first-line therapy to treat acid-related diseases worldwide. However, they have a number of limitations including slow onset of action, influence by cytochrome P450 polymorphisms, unsatisfactory effects at night, and instability in acidic conditions. Alternative formulations of conventional PPIs have been developed to overcome these problems; however, these drugs have only introduced small advantages for controlling acid secretion compared to conventional PPIs. Potassium-competitive acid blockers (P-CABs) were developed and have beneficial effects including rapid, long-lasting, and reversible inhibition of the gastric hydrogen potassium ATPase, the proton pump of the stomach. Vonoprazan was recently innovated as a novel, orally active P-CAB. It is currently indicated for the treatment of gastric and duodenal ulcers, reflux esophagitis, and prevention of low-dose aspirin- or nonsteroidal anti-inflammatory drug-related gastric and duodenal ulcer recurrence in Japan. Vonoprazan does not require enteric coating as it is acid-stable, and it can be taken without food because it is quickly absorbed. Vonoprazan accumulates in parietal cells under both acidic and neutral conditions. It does not require an acidic environment for activation, has long-term stability at the site of action, and has satisfactory safety and tolerability. Thus, vonoprazan may address the unmet medical need for the treatment of acid-related diseases.

Vonoprazan prevents low-dose aspirin-associated ulcer recurrence: randomised phase 3 study

OBJECTIVE

Compare efficacy and safety of vonoprazan and lansoprazole for secondary prevention of low-dose aspirin (LDA)-associated peptic ulcers in a 24-week study and long-term extension therapy in separate study.

DESIGN

Double-blind, randomised, non-inferiority study; single-blind extension study at 104 Japanese sites, including 621 patients (439 in extension) with a history of peptic ulcers who required long-term LDA therapy. Randomised (1:1:1, computer generated) patients received lansoprazole 15 mg (n=217), vonoprazan 10 mg (n=202) or vonoprazan 20 mg (n=202) once daily for 24 weeks (double blind) and ≤2 years (extension). The following measurements were made: 24-week (primary outcome; double blind) and 12-week peptic ulcer recurrence rate, 24-week GI bleeding rate, cumulative incidences of peptic ulcer recurrence and GI bleeding, treatment-emergent adverse events, laboratory results, serum gastrin and pepsinogen I/II concentrations.

RESULTS

The 24-week peptic ulcer recurrence rate was 2.8%, 0.5% and 1.5% in the lansoprazole 15 mg, vonoprazan 10 mg and vonoprazan 20 mg groups, respectively. Vonoprazan was non-inferior (Farrington and Manning test: margin 8.7%, significance level 2.5%) to lansoprazole. In the post hoc analyses of the extension study, peptic ulcer recurrence rates were significantly lower with vonoprazan 10 mg (log-rank test, P=0.039), but not vonoprazan 20 mg (P=0.260), compared with lansoprazole 15 mg. GI bleeding rates were higher with lansoprazole compared with two doses of vonoprazan in both 24-week study and extension study.

CONCLUSION

Vonoprazan (10 and 20 mg) was as effective as lansoprazole (15 mg) in preventing peptic ulcer recurrence during LDA therapy, had a similar long-term safety profile and was well tolerated.

TRIAL REGISTRATION NUMBERS

NCT01452763; NCT01456247.