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

Randomised clinical trial: tegoprazan, a novel potassium-competitive acid blocker, or lansoprazole in the treatment of gastric ulcer

BACKGROUND

Tegoprazan is a novel potassium-competitive acid blocker for the treatment of acid-related disorders.

AIMS

To assess whether tegoprazan is non-inferior to lansoprazole in terms of efficacy and safety in patients with gastric ulcers.

METHODS

In this phase 3, double-blind, active control, multicentre study, 306 gastric ulcer patients were randomised to one of three treatment groups: tegoprazan 50 mg, tegoprazan 100 mg and lansoprazole 30 mg once daily for 4 or 8 weeks. The primary endpoint was the cumulative proportion of patients with healed ulcers confirmed by endoscopy up to 8 weeks from treatment initiation. Symptoms and safety were assessed.

RESULTS

In the full analysis set, the cumulative healing rates at week 8 were 94.8% (91/96) for the tegoprazan 50 mg, 95.0% (94/99) for the tegoprazan 100 mg and 95.7% (89/93) for the lansoprazole 30 mg groups. At week 4, the respective healing rates were 90.6% (87/96), 91.9% (91/99), and 89.2% (83/93). In per protocol analysis, 4-week healing rates were 95.4% (84/88), 94.6% (88/93) and 92.9% (79/85) for tegoprazan 50 mg, tegoprazan 100 mg and lansoprazole 30 mg, respectively. Both doses of tegoprazan were non-inferior to lansoprazole in ulcer healing at 4 and 8 weeks. The incidence of drug-related treatment-emergent adverse events did not differ among groups. The increase in serum gastrin concentration was not higher in tegoprazan-treated patients than in lansoprazole-treated patients.

CONCLUSIONS

Tegoprazan 50 or 100 mg were not inferior to lansoprazole 30 mg once daily in the treatment of gastric ulcers.

Efficacy of second-line regimens for Helicobacter pylori eradication treatment: a systemic review and network meta-analysis

BACKGROUND

Current guidelines recommend bismuth-containing quadruple therapy (BQT) and quinolone-containing therapy after failure of first-line Helicobacter pylori eradication therapy. However, the optimum regimen of second-line eradication therapy remains elusive. We conducted a network meta-analysis to compare the relative efficacy of 16 second-line H. pylori eradication regimens.

METHODS

Three major bibliographic databases were reviewed to enrol relevant randomised controlled trials between January 2000 and September 2018. Network meta-analysis was conducted by STATA software and we performed subgroup analysis in countries with high clarithromycin resistance and high levofloxacin resistance, and in patients with documented failure of first-line triple therapy.

RESULTS

Fifty-four studies totalling 8752 participants who received 16 regimens were eligible for analysis. Compared with a 7-day BQT, use of probiotic add-on therapy during, before, and after second-line antibiotic regimens, quinolone-based sequential therapy for 10-14 days, quinolone-based bismuth quadruple therapy for 10-14 days, bismuth quadruple therapy for 10-14 days, and quinolone-based triple therapy for 10-14 days were significantly superior to the other regimens. Subgroup analysis of countries with high clarithromycin resistance and high levofloxacin resistance revealed that the ranking of second-line eradication regimens was distributed similarly in each group, as well as in patients with failure of first-line triple therapy.

CONCLUSION

We conducted a detailed comparison of second-line H. pylori regimens according to different antibiotic resistance rates and the results suggest alternative treatment choices with potential benefits beyond those that could be achieved using salvage therapies recommended by guidelines.

Upper gastrointestinal bleeding in Japanese patients with ischemic heart disease receiving vonoprazan or a proton pump inhibitor with multiple antithrombotic agents: A nationwide database study

BACKGROUND

Vonoprazan has been launched as an alternative to proton-pump inhibitors (PPIs). This was the first study to compare the occurrence of upper gastrointestinal bleeding (UGIB) with vonoprazan treatment to that with PPI treatment in patients with ischemic heart disease (IHD) taking ≥2 antithrombotic agents, including those receiving dual antiplatelet therapy (DAPT).

METHODS

Using Japanese Diagnosis Procedure Combination data from 2016 to 2017, we identified 16,415 patients with IHD who were prescribed ≥2 antithrombotic agents, including new antiplatelet medication with concurrent vonoprazan (n = 2226 or PPIs n = 14,189). UGIB occurrence was analyzed using an inverse probability-weighted Cox proportional hazards model. Non-inferiority of vonoprazan to PPI treatment for UGIB occurrence was assessed.

RESULTS

Six-month incidence of UGIB in patients treated with vonoprazan and PPIs was 3.14% 70/2226 and 4.17% (591/14,189), respectively. The adjusted hazard ratio (aHR) of 0.84 was significantly below the non-inferiority margin (HR 2.06) (p < 0.0001), and thus demonstrated that vonoprazan treatment was non-inferior to PPIs in terms of occurrence of UGIB events. The difference between the 2 treatments was also not statistically significant [aHR 0.84; 95% confidence interval (CI): 0.65-1.07; p = 0.154). In a subgroup analysis, UGIB occurrence with vonoprazan and other PPI treatment in patients receiving DAPT was 2.82% (22/779) and 3.96% (209/5276) respectively; a non-significant difference (aHR 0.74; 95% CI: 0.48-1.16; p = 0.189) that demonstrated non-inferiority (p < 0.0001).

CONCLUSIONS

Vonoprazan was non-inferior to PPIs in terms of UGIB occurrence over 6 months in patients with IHD receiving ≥2 antithrombotic agents, including new antiplatelet medication.

Novel Therapies for Gastroesophageal Reflux Disease: Beyond Proton Pump Inhibitors

PURPOSE OF REVIEW

Despite the many areas of unmet needs in gastroesophageal reflux disease (GERD), proton pump inhibitors (PPIs) remain the cornerstone of medical therapy. However, since their introduction, the therapeutic limitations of PPIs in GERD management have been increasingly recognized.

RECENT FINDINGS

In this review we discuss the new medical, endoscopic, and surgical therapeutic modalities that have been developed over the last decade. They include the potassium-competitive acid blockers (P-CABs) which provide a rapid onset, prolonged, and profound acid suppression, mucosal protectants which promote the physiological protective barrier of the esophageal mucosa, new prokinetics and neuromodulators. There are growing numbers of novel therapeutic endoscopic techniques that are under investigation or were recently introduced into the market, further expanding our therapeutic armamentarium for GERD. The development of diverse therapeutic modalities for GERD, despite the availability of PPIs, suggests that there are many areas of unmet need in GERD that will continue and drive future exploration for novel therapies.

New Developments in the Diagnosis and Management of Gastroesophageal Reflux

PURPOSE OF REVIEW

To examine recent key developments in the pathophysiology, diagnosis, and treatment of gastroesophageal reflux disease (GERD).

RECENT FINDINGS

Newer research has suggested cytokine-mediated inflammation may play a role in the physiology of GERD, implying that the underlying mechanism may not be entirely related to chemical damage due to acid. Aided by novel technologies, diagnostic testing is also moving toward elucidating individual mechanisms and better defining specific GERD phenotypes with the goal of providing directed therapy. This is especially important in current times given the increase in coverage of adverse events reportedly linked to long-term proton pump inhibitor use.

SUMMARY

As patients are looking for potential alternatives, we highlight the key recent updates in pathophysiology and understanding of GERD and current medical and endoscopic/surgical options and explore the exciting treatments in the pipeline.

Systematic Analysis of Monoterpenes: Advances and Challenges in the Treatment of Peptic Ulcer Diseases

Peptic ulcer disease (PUD) is a multifactorial and complex disease caused by an imbalance of protective and aggressive factors (endogenous and exogenous). Despite advances in recent years, it is still responsible for substantial mortality and triggering clinical problems. Over the last decades, the understanding of PUD has changed a lot with the discovery of Helicobacter pylori infection. However, this disease continues to be a challenge due to side-effects, incidence of relapse from use of various anti-ulcer medicines, and the rapid appearance of antimicrobial resistance with current H. pylori therapies. Consequently, there is the need to identify more effective and safe anti-ulcer agents. The search for new therapies with natural products is a viable alternative and has been encouraged. The literature reports the importance of monoterpenes based on the extensive pharmacological action of this class, including wound healing and anti-ulcerogenic agents. In the present study, 20 monoterpenes with anti-ulcerogenic properties were evaluated by assessing recent in vitro and in vivo studies. Here, we review the anti-ulcer effects of monoterpenes against ulcerogenic factors such as ethanol, nonsteroidal anti-inflammatory drugs (NSAIDs), and Helicobacter pylori, highlighting challenges in the field.

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.

The potential role of potassium-competitive acid blockers in the treatment of gastroesophageal reflux disease

PURPOSE OF REVIEW

Gastroesophageal reflux disease (GERD) is primarily a motor disorder, but its pathogenesis is multifactorial. Although gastric acid secretion is usually normal in GERD patients, treatment with proton pump inhibitors (PPIs) has become the standard of care, despite increasing awareness of their shortcomings. In this article, a new class of antisecretory drugs (namely potassium-competitive acid blockers, P-CABs), developed to overcome these limitations, is discussed.

RECENT FINDINGS

P-CABs block the K exchange channel of the proton pump, resulting in rapid, competitive, reversible inhibition of acid secretion. These drugs offer a more rapid elevation of intragastric pH than PPIs, while maintaining similar antisecretory effect, the duration of which is dependent on half-life and can be prolonged with extended release formulations. Thus, P-CABs offer advances in the treatment of GERD including rapid heartburn relief, faster and more reliable healing of severe grades of erosive esophagitis, as a consequence of better control of nighttime acid secretion than PPIs.

SUMMARY

P-CABs overcome many of the drawbacks of PPIs. The unique antisecretory effects of vonoprazan might be especially useful in the long-term treatment of patients with Barrett's esophagus.

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.

Randomised clinical trial: vonoprazan versus lansoprazole for the initial relief of heartburn in patients with erosive oesophagitis

BACKGROUND

Proton pump inhibitors (PPIs) are widely used to treat gastro-oesophageal reflux disease (GORD). However, the onset of action is considered slow and PPIs cannot completely block acid secretion at night. A new potassium-competitive acid blocker (P-CAB) can rapidly block acid secretion. However, whether this P-CAB can relieve GORD symptoms quickly and adequately soon after starting treatment is unknown.

AIM

To determine how rapidly vonoprazan and lansoprazole provide heartburn relief.

METHODS

Patients (n = 32) with endoscopically confirmed erosive oesophagitis who experienced heartburn at least once a week were randomised in a double-blind manner to receive either daily vonoprazan (20 mg) or lansoprazole (30 mg) before breakfast for 14 days. Day time and night time heartburn were assessed daily throughout the study using a five-point Likert scale. The primary endpoint was the first day of complete day and night heartburn relief for at least seven consecutive days. The ethics committees of the participating institutions approved the study protocol.

RESULTS

Heartburn was relieved sooner with vonoprazan than with lansoprazole (P < 0.05, log-rank test). Heartburn was completely relieved in 31.3% and 12.5% of patients on day 1 with vonoprazan and lansoprazole, respectively. Significantly more patients achieved complete nocturnal heartburn relief with vonoprazan than lansoprazole (P < 0.01). Both regimens were well tolerated.

CONCLUSIONS

Complete sustained heartburn relief was achieved sooner with vonoprazan than with lansoprazole during the first week of therapy. (UMIN000018776).

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.

Systematic review with meta-analysis: Vonoprazan, a potent acid blocker, is superior to proton-pump inhibitors for eradication of clarithromycin-resistant strains of Helicobacter pylori

BACKGROUND

Vonoprazan is a novel gastric acid suppressant that is applied in Japan to treat gastric diseases including Helicobacter pylori (H. pylori) infection. This meta-analysis aimed to summarize the ability of vonoprazan to eradicate clarithromycin-susceptible and clarithromycin-resistant H. pylori strains.

MATERIALS AND METHODS

A systematic search was performed using PubMed, EMBASE, Web of Science, and Cochrane Library. Studies were included if they evaluated eradication rates of vonoprazan-based and conventional PPI-based triple therapies and checked for clarithromycin susceptibility of H. pylori.

RESULTS

We identified 5 studies including a total of 1599 patients containing data regarding H. pylori with clarithromycin susceptibility. Among those infected with clarithromycin-susceptible H. pylori, eradication rates for vonoprazan-based and conventional PPI-based therapies did not significantly differ in either the randomized (RCT; pooled eradication rates, 95.4% vs 92.8%; pooled odds ratio [OR], 1.63; 95% confidence intervals [CI], 0.74-3.61; P = .225) and nonrandomized (NRCT; pooled eradication rates, 92.9% vs 86.2%; OR, 4.58; 95% CI, 0.67-31.45; P = .122) controlled trials. However, vonoprazan-based triple therapy was significantly superiority to PPI-based therapy for patients with clarithromycin-resistant strains in both RCT (pooled eradication rates, 82.0% vs 40.0%; OR, 6.83; 95% CI, 3.63-12.86; P < .0001) and NRCT (pooled eradication rates, 80.8% vs 41.8%; OR, 4.98; 95% CI, 2.47-10.03; P < .0001).

CONCLUSIONS

Vonoprazan-based and conventional PPI-based therapies are similarly effective for the eradication of clarithromycin-susceptible H. pylori strains. Vonoprazan is superior to conventional PPI-based therapy for the eradication of clarithromycin-resistant H. pylori strains. However, clarithromycin was misused because the combination of vonoprazan and amoxicillin cures approximately 80% of infections without clarithromycin.