The binding selectivity of vonoprazan (TAK-438) to the gastric H+, K+ -ATPase

Efficacy and safety of vonoprazan-amoxicillin dual therapy versus bismuth-containing quadruple therapy for patients with Helicobacter pylori infection: a meta-analysis

Introduction

This meta-analysis aims to compare the efficacy and safety of vonoprazan-amoxicillin (VA) dual therapy in comparison to bismuth-containing quadruple therapy (BQT) for patients with Helicobacter pylori (H. pylori) infection.

Materials and methods

Four databases (PubMed, Embase, Web of Science, and Cochrane Library) were searched published from establishment of database to June 1, 2024, for articles studying VA dual therapy compared to BQT for patients with H. pylori infection. Meta-analyses of eradication rates, adverse events, compliance and cost were preformed.

Results

A total of 17 studies were included for meta-analysis. Compared with BQT, VA increased the incidence of H. pylori eradication rate, with significant difference under the ITT analysis (86.9% vs. 80.4%, RR = 1.07, 95% CI: 1.01-1.12, p = 0.01) but there no significant difference under the PP analysis (90.7% vs. 86.5%, RR = 1.03, 95% CI: 0.99-1.08, p = 0.13). Besides, VA significantly increased compliance (RR = 1.03, 95% CI: 1.01-1.05, p < 0.01) and decreased the occurrence of total adverse events (27.0% vs. 11.5%, RR = 0.43, 95% CI: 0.37-0.51, p < 0.01). Furthermore, VA has lower cost compared to BQT.

Conclusion

Our findings indicated that VA dual therapy provided a higher eradication rate, enhanced compliance, decreased adverse events, and lowered cost relative to BQT for patients with H. pylori infection.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024576738, identifier CRD42024576738 (PROSPERO).

Efficacy and eradication effect of vonoprazan and high-dose amoxicillin dual therapy in CagA+VacA+ Helicobacter pylori infected patients

OBJECTIVE

Helicobacter pylori (HP) eradication rates are higher by treated with the potassium-competitive acid blocker vonorasan than with proton pump inhibitors (PPIs). Herein, this study analyzed the clinical efficacy of vonoprazan combined with high-dose amoxicillin for dual therapy in personalized eradication of HP.

METHODS

This retrospective analysis included 452 patients with type I HP who were assigned to the observation and control groups. Cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA) antibodies were detected using the H. pylori antibody typing classification assay kit by Western blot. The control group underwent PPI quadruple therapy (oral administration of esomeprazole, amoxicillin, clarithromycin, and colloidal bismuth subcitrate). The observation group was treated with vonoprazan combined with high-dose amoxicillin orally. The clinical efficacy was evaluated after 14 days of treatment, and adverse reactions during treatment were compared. The eradication rates for different HP types in the two groups were detected using a 13C-urea breath test.

RESULTS

There was no significant difference between the control and observation groups in sex, age, BMI, disease duration, smoking history, or drinking history. The observation group exhibited higher total effective rates and better eradication effects than the control group. The CagA+, VacA+, or CagA+VacA+ type patients showed no statistical difference in the incidence of adverse reactions, but the observation group showed a lower total incidence of adverse reactions than the control group.

CONCLUSION

Vonoprazan combined with high-dose amoxicillin has better clinical efficacy and eradication effect for patients with CagA+VacA+ HP, along with reduced adverse reactions.

Efficacy of Potassium-Competitive Acid Blockers Versus Proton Pump Inhibitors for Gastric Ulcers: Bayesian and Frequentist Network Meta-Analysis With Cross-Inference Through a Quality management System

Purpose

Proton pump inhibitors (PPIs) have been the mainstay treatment for gastric ulcer (GU) for over 30 years. However, since the discovery of a new class of acid suppressants, potassium-competitive acid blockers (P-CABs), the desire for a therapeutic agent has continued and the clinical trials on P-CABs have been conducted. In this regard, we aimed to assess whether P-CABs are noninferior to PPIs in patients with GU in terms of efficacy.

Methods

We performed a systematic review and network meta-analysis (NMA) based on randomized controlled trials (RCTs). Additionally, we used a new methodology of inference concept with the purpose of grouping between P-CABs and PPIs. Moreover, our quality management system was integrated throughout the research to ensure data accuracy.

Findings

We initially screened 438 studies and extracted 10 homogeneous GU RCTs with 6315 participants. The odds ratios (ORs) for the 4-week cure rate in Bayesian + frequentist NMA, tegoprazan 100 mg (OR = 4.14, 95% credible interval [CI] 0.56-26.3) and pantoprazole 40 mg (OR = 4.12, 95% CI 1.90-8.88) were the largest, respectively. The ORs for the 8-week cure rate in Bayesian + frequentist NMA, lansoprazole 30 mg (OR = 8.77, 95% credible interval [CI] 0.95-78.9) and lansoprazole 30 mg (OR = 7.91, 95% CI 2.60-24.03) was the largest, respectively.

Conclusions

The results of the NMA reveal that the cure rates of P-CABs in cases of GU were not inferior to those of PPIs. As the inference by grouping PPIs and P-CABs, the results showed similar trends in terms of effectiveness between the two therapeutic classes.

Current research status and trends of potassium-competitive acid blockers in the treatment of acid-related diseases: a bibliometric analysis

Objective

To explore the current research status and trends of potassium-competitive acid blockers (P-CABs) in the treatment of acid related diseases (ARDs) using bibliometric analysis.

Materials and methods

We collected publications related to P-CAB in the treatment of acid-related diseases in the Web of Science (WOS) Core Collection from the establishment of the database to 30 June 2024. We evaluated the publication volume and citation status over the years using the WOS platform, and visualized the authors, countries, institutions, keywords, and citations of the publications using CiteSpace and VOSviewer.

Results

This study included a total of 455 articles. The number of publications and citations related to research has been increasing year by year. The results show that the scholars with the highest number of publications mainly come from South Korea and Japan. Scholars such as Geun Seog Song, Bongtae Kim, and Nobuhiro Inatomi produced many works in related fields. The most popular drug in this field was vonoprazan, and research on this drug mainly focused on the effectiveness and safety evaluation of ARDs such as Helicobacter pylori infection, gastroesophageal reflux disease, peptic ulcers, etc. Researchers were concerned about the evaluation of treatment regimens and efficacy comparison between P-CABs and traditional proton pump inhibitors (PPIs) in the treatment of ARDs. At the same time, researchers are also closely monitoring the potential adverse reactions and long-term adverse outcomes of clinical application of P-CABs for ARDs.

Conclusion

The clinical application of P-CABs, represented by vonoprazan, in ARDs is receiving widespread attention from researchers. The exploration of the application of this type of drug in ARDs is constantly expanding, and it is a research field with great clinical value and research potential.

Evaluating Vonoprazan for the treatment of erosive GERD and heartburn associated with GERD in adults

INTRODUCTION

Gastroesophageal reflux disease (GERD) is a common debilitating chronic disease presenting in two main forms based on esophageal mucosal appearance, the erosive reflux disease (ERD) and the non-erosive reflux disease (NERD). Acid secretion is a key factor in the disease pathogenesis and management. Potent acid-suppressant drugs have been manufactured since the mid of 1970s, initially with histamine-H2-receptors antagonists, and later, inhibitors of the proton pump (H+-K+-ATPase).More recently, potassium-competitive acid blockers (p-CABs), particularlyVonoprazan, have been introduced. Vonoprazan has shown high efficacy and safety profiles and exhibits several advantages that allow to overcome shortcomings of proton pump inhibitors (PPIs).

AREAS COVERED

In this review, we provide an updated summary of Vonoprazan pharmacodynamics and its role in clinical practice for the management of erosive esophagitis and GERD-related heartburn. Moreover, we discuss characteristics of Vonoprazan that allow to bypass some limitations of the older PPIs.

EXPERT OPINION

Long-term safety and efficacy of Vonoprazan have already been demonstrated for the induction and maintenance of ERD, preventing nocturnal acid breakthrough, reducing reflux symptoms in non-responder to standard therapy. Ongoing and future studies are expected to further elucidate its long-term benefits and potential applications in other acid-related disorders.

Ten-day versus 14-day vonoprazan-amoxicillin high-dose dual therapy for Helicobacter pylori eradication in China: A multicenter, open-label, randomized study

BACKGROUND AND AIM

Only a few studies have investigated the efficacy and safety of different durations of vonoprazan and amoxicillin (VA) high-dose dual therapy for the eradication of Helicobacter pylori. We aimed to compare the efficacy and safety of 10 days versus 14 days of VA high-dose dual therapy for H. pylori eradication.

METHODS

This study was conducted in 14 centers in China. A total of 250 patients infected with H. pylori were randomly assigned to Group VA-10 or VA-14. Both groups received the VA dual therapy (vonoprazan 20 mg twice daily + amoxicillin 1000 mg three times daily). The primary endpoint was the H. pylori eradication rate. Secondary endpoints included adverse events and patient compliance.

RESULTS

Group VA-10 achieved eradication rates of 89.60%, 91.06%, and 91.67% as determined by the intention-to-treat (ITT), modified intention-to-treat (MITT), and per-protocol (PP) analysis, respectively. The eradication rates were similar to those in Group VA-14: 91.20%, 93.44%, and 93.39%. The difference and 90% confidence interval boundary -1.60% (-7.73% to 4.53%) in the ITT analysis, -2.39% (-8.00% to 3.23%) in the MITT analysis, and -1.72% (-7.29% to 3.85%) in the PP analysis were greater than the predefined noninferiority margin of -10%, establishing a noninferiority of Group VA-10 versus Group VA-14 (noninferiority P = 0.001 in ITT analysis, P < 0.001 in MITT analysis, and P < 0.001 in PP analysis, respectively). No significant differences were observed in adverse events between the two groups.

CONCLUSIONS

Ten-day VA dual therapy achieves comparable efficacy and safety to the 14-day regimen in Chinese population, providing patients with greater convenience and economic benefits.

Evaluating vonoprazan and tegoprazan for gastroesophageal reflux disease treatment in Chinese Healthcare: an EVIDEM framework analysis

BACKGROUND

In Chinese healthcare settings, drug selection decisions are predominantly influenced by the Pharmacy & Therapeutics Committee (PTC). This study evaluates two recently introduced potassium-competitive acid blockers, vonoprazan (VPZ) and tegoprazan (TPZ), utilizing the Evidence and Value: Impact on DEcisionMaking (EVIDEM) framework.

METHODS

The study employed the 10th edition of EVIDEM, which includes a core model with five domains and 13 criteria. Two independent expert panels were involved: the PTC expert panel, tasked with assigning weights using a 5-point scale, defining scoring indicators, examining the evidence matrix, scoring, and decision-making; and the evidence matrix expert panel, responsible for conducting a systematic literature review, creating the evidence matrix, and evaluating the value contributions of VPZ and TPZ.

RESULTS

The analysis estimated the value contributions of VPZ and TPZ to be 0.59 and 0.54, respectively. The domain of 'economic consequences of intervention' showed the most significant variation in value contribution between the two drugs, followed by 'comparative outcomes of intervention' and 'type of benefit of intervention'.

CONCLUSION

Employing the EVIDEM framework, VPZ's value contribution was found to be marginally superior to that of TPZ. The EVIDEM framework demonstrates potential for broader application in Chinese medical institutions.

Comparative Efficacy and Safety of Potassium-Competitive Acid Blockers vs. Proton Pump Inhibitors for Peptic Ulcer with or without Helicobacter pylori Infection: A Systematic Review and Network Meta-Analysis

Novel potassium-competitive acid blockers (P-CABs) have emerged as effective acid-suppressive drugs in recent years, replacing proton pump inhibitors (PPIs). We aim to compare the efficacy and safety of P-CABs versus PPIs in the treatment of peptic ulcers with or without Helicobacter pylori (H. pylori) infection. We searched in PubMed, Embase, WOS, Cochrane Library, ClinicalTrials.gov, CNKI, and Wanfang databases (all years up to January 2024). Efficacy and safety outcomes were evaluated using odds ratio (OR) and 95% confidence intervals (CI). The Surface Under the Cumulative Ranking (SUCRA) probabilities were used to rank each intervention. Among 14,056 studies screened, 56 studies involving 9792 participants were analyzed. Vonoprazan demonstrated the best efficacy in ulcer healing rate and H. pylori eradication rate (SUCRA = 86.4% and 90.7%, respectively). Keverprazan ranked second in ulcer healing rates (SUCRA = 76.0%) and was more effective in pain remission rates (SUCRA = 91.7%). The risk of adverse events was low for keverprazan (SUCRA = 11.8%) and tegoprazan (SUCRA = 12.9%), and moderate risk for vonoprazan (SUCRA = 44.3%) was demonstrated. Compared to lansoprazole, vonoprazan exhibited a higher risk of drug-related adverse events (OR: 2.15; 95% CI: 1.60-2.89) and serious adverse events (OR: 2.22; 95% CI: 1.11-4.42). Subgroup analysis on patients with H. pylori-positive peptic ulcers showed that vonoprazan was at the top of the SUCRA rankings, followed by keverprazan. Vonoprazan showed superior performance in peptic ulcers, especially for patients with H. pylori-positive peptic ulcers. However, the risk of adverse events associated with vonoprazan should be noted. Keverprazan has also shown good therapeutic outcomes and has performed better in terms of safety.

Comparison of vonoprazan-based dual therapy with vonoprazan-based bismuth quadruple therapy for treatment-naive patients with Helicobacter pylori infection: A propensity score matching analysis

Vonoprazan, a novel acid suppressant and the first potassium-competitive acid blocker, has the potential to enhance the eradication rate of Helicobacter pylori due to its robust acid-suppressing capacity. This study aimed to compare the efficacy of vonoprazan-based dual therapy (vonoprazan-amoxicillin, VA) with vonoprazan-based bismuth quadruple therapy (VBQT) as a first-line treatment for H pylori infection. This retrospective single-center non-inferiority study was conducted in China. Treatment-naive H pylori-positive patients aged 18 to 80 received one of the 2 treatment regimens at our center. The VA group received vonoprazan 20 mg twice daily and amoxicillin 1000 mg 3 times daily for 14 days, whereas the VBQT group received vonoprazan 20 mg, amoxicillin 1000 mg, clarithromycin 500 mg, and bismuth potassium citrate 220 mg twice daily for 14 days. The eradication rate was evaluated 4 to 6 weeks after treatment using the carbon-13/14 urea breath test. Propensity score matching was used to analyze eradication rates, adverse events (AEs), and patient compliance between the 2 groups. Initially, 501 patients were included, and after propensity score analysis, 156 patients were selected for the study. Intention-to-treat analysis showed eradication rates of 87.2% (95% CI, 79.8-94.6%) for the VA group and 79.5% (95% CI, 70.5-88.4%) for the VBQT group (P = .195). Per-protocol analysis demonstrated rates of 94.4% (95% CI, 89.2-99.7%) for the VA group and 96.8% (95% CI, 92.4-100%) for the VBQT group (P = .507). Non-inferiority was confirmed between the 2 groups, with P values < .025. The VA group showed a lower rate of AEs (10.3% vs 17.9%, P = .250) compared to the VBQT group. There were no significant differences in patient compliance between the 2 groups. In treatment-naive patients with H pylori infection, both the 14-day VA and VBQT regimens demonstrated comparable efficacy, with excellent eradication rates. Moreover, due to reduced antibiotic usage, lower rate of AEs, and lower costs, VA dual therapy should be prioritized.

Vonoprazan: A Review in Helicobacter pylori Infection

Treatment for the eradication of Helicobacter pylori infection, a leading cause of peptic ulcer disease and an important risk factor for gastric cancer and mucosa-associated lymphoid tissue lymphoma, is indicated whenever infection is identified. However, treatment success rates with current guideline-recommended proton-pump inhibitor (PPI)-based regimens remain suboptimal, with one potential factor associated with treatment failure being inadequate acid suppression. Vonoprazan (Voquezna®) is a first-in-class potassium-competitive acid blocker with the potential to provide potent and sustained acid suppression. Following clinical trials conducted mainly in Asia (supported by post-marketing experience from Asia) and the phase III PHALCON-HP trial conducted in the USA and Europe, vonoprazan is now approved in the USA for use in combination with amoxicillin (dual therapy) or amoxicillin and clarithromycin (triple therapy) for the treatment of H. pylori infection in adults. The vonoprazan-based dual and triple therapy regimens were generally well tolerated in PHALCON-HP. In addition, vonoprazan has advantages including a rapid onset of action and no food effect, making vonoprazan-based dual and triple therapy regimens valuable alternatives to standard PPI-based triple therapy in the treatment of H. pylori infection.

Potassium-competitive acid blockers: rethinking acid suppression for gastroesophageal reflux disease and Helicobacter pylori

Gastroesophageal reflux disease (GERD) and Helicobacter pylori (H. pylori) infection are different disease states that are united by the core role of acid suppression in their management. In GERD, proton pump inhibitors (PPIs) have long been standard therapy based on abundant positive clinical trial data supporting their efficacy and safety. In H. pylori, PPIs are also a critical element of therapy in combination with 1 or more antibiotics to achieve and maintain a pH that maximizes the efficacy of therapy. Despite the considerable clinical success and widespread use of PPIs, room remains for agents with differentiated pharmacokinetic and pharmacodynamic profiles. The potassium-competitive acid blockers (PCABs) are mechanistically distinct from PPIs but are acid-stable and do not require activation of the proton pump by coadministration of food. In pharmacodynamic studies, these agents have shown greater durations of acid suppression above the critical threshold of pH 4 (for GERD) and pH 6 (for H. pylori), which have been shown to optimize therapeutic efficacy in these settings. These results have translated in clinical studies to similar and, in some cases, improved outcomes relative to PPIs in these disease states. This review summarizes current knowledge on the physiology of acid secretion, pathophysiology and management of GERD and H. pylori, and key characteristics and clinical trial data for PPIs and PCABs.

Acid-suppressive drugs: A systematic review and network meta-analysis of their nocturnal acid-inhibitory effect

BACKGROUND AND AIMS

Acid-suppressive drugs (ASDs) are widely used in many gastric acid-associated diseases. Nocturnal acid breakthrough has been a common problem of many ASDs, such as proton-pump inhibitors (PPIs) and H2 -receptor antagonists (H2RAs). Potassium-competitive acid blockers (P-CABs) are expected to solve this continuing conundrum. This article examined major ASDs and compared them with placebo in terms of nocturnal acid-inhibitory effects, using a network meta-analysis of randomized controlled trials (RCTs).

METHODS

To compare the effectiveness of major ASDs, a Bayesian network meta-analysis (NMA) was applied to process data extracted from RCTs. The plausible ranking for each regimen and some subgroups were assessed by surface under the cumulative ranking curves (SUCRA).

RESULTS

Fifty-five RCTs were conducted with 2015 participants. In terms of nocturnal acid-inhibitory effects, the overall results showed that tegoprazan (SUCRA 91.8%) and vonoprazan (SUCRA 91.0%) had the best performance, followed by new PPIs (including tenatoprazole and ilaprazole) (SUCRA 76.6%), additional H2RAs once at bedtime (AHB) (SUCRA 61.3%), isomer PPIs (including esomeprazole and dexlansoprazole) (SUCRA 38.6%), revaprazan (SUCRA 34.7%), traditional PPIs (including omeprazole, rabeprazole, pantoprazole, lansoprazole) (SUCRA 32.6%), H2RAs (SUCRA 23.1%), and placebo (SUCRA 0.3%). In some subgroups, the nocturnal acid-inhibitory effect of vonoprazan or tegoprazan was better than most of the other regimens, even new PPIs and AHB.

CONCLUSIONS

This is the first study to compare the effect of ASDs on inhibiting nocturnal acid breakthrough. Overall, in terms of nocturnal acid-inhibitory effect, vonoprazan and tegoprazan had an advantage against other regimens including H2RAs, isomer PPIs, traditional PPIs, AHB, and new PPIs. Even in some subgroups, such as language classification (English), types of study design (crossover-RCT), age (≤40 years), BMI (18.5-24.9 kg/m2 ), continent (Asia and North America), disease status (health), the duration of therapy (2 weeks), and time of administration (at daytime or at night-time), the nocturnal acid-inhibitory effect of vonoprazan or tegoprazan were better than most regimens, even AHB and new PPIs.

Comparison of the Efficacy of Two-Week Vonoprazan Versus Lansoprazole-Based Quadruple Sequential Antibiotic Therapy in Eradicating Helicobacter pylori Infection: A Non-randomized Clinical Trial

AIM

The prevalence of Helicobacter pylori is escalating in developing countries, exacerbated by unjustified antibiotic usage, which leads to increased resistance. This trend has been notably amplified since the COVID-19 pandemic. Consequently, the effectiveness of existing eradication regimens has been compromised. This study aimed to compare the efficacy of two weeks of vonoprazan-based quadruple sequential therapy and lansoprazole-based quadruple sequential therapy in treating H. pylori infection.  Methods: A non-randomized clinical trial was conducted over 18 months at the Department of Gastroenterology, Lahore General Hospital, Lahore, Pakistan. It included patients presenting with dyspepsia, as defined by the Rome IV criteria, and who tested positive on the urea breath test. Patients were divided into two groups, i.e., Group A and Group B. Group A patients received lansoprazole 30 mg + amoxicillin + tinidazole + tab. colloidal bismuth subcitrate for the first seven days, followed by lansoprazole + levofloxacin + azithromycin + colloidal bismuth subcitrate. Group B patients received vonoprazan + amoxicillin + tinidazole + colloidal bismuth subcitrate for the first seven days, followed by vonoprazan + levofloxacin + azithromycin + colloidal bismuth subcitrate. Both regimes continued for 14 days. Four weeks after 14 days of the treatment, an early morning urea breath test was conducted to evaluate the efficacy of the treatment. Patients were scheduled for follow-up visits at seven and 14 days post-treatment initiation to record adverse events and assess compliance with the treatment regimen. Patients who lost the follow-up and remained non-compliant to the medications were excluded from the final data analysis as per standard protocols of the per-protocol analysis.  Results: A total of 252 patients were included. In Group A and Group B, 6/126 (4.76%) and 8/126 (6.35%) of the patients were lost to follow-up, respectively. The non-compliance rate in Group A was 5/126 (3.97%), compared to Group B with 3/126 (2.38%). Finally, the per-protocol analysis of the results included 115 patients in each group. Baseline characteristics, including demographics, lifestyle, and clinical factors, were comparable between groups with p-values of 0.138 for age, 0.356 for gender, 0.126 for BMI, 0.495 for residence, 0.500 for water source, 0.866 for meal habit, 0.863 for smoking, 0.188 for nonsteroidal anti-inflammatory drug (NSAID) use, 0.145 for proton pump inhibitor (PPI) use, 0.213 for antibiotics, and 0.456 for treatment history. Both treatments effectively eradicated H. pylori, as determined by a negative urea breath test at four weeks post-treatment, with Group B showing a higher eradication rate of 96.5% compared to 92.2% in Group A, although the difference was not statistically significant (p = 0.153). There was no difference in adverse effects in both treatment groups (p-value > 0.05).  Conclusion: The study found that while the vonoprazan-based regime exhibited a slightly higher eradication rate of H. pylori compared to lansoprazole, the difference was not statistically significant. It was concluded that both regimens demonstrated comparable efficacy and similar profiles of adverse effects in treating H. pylori infection.

Effect of potassium-competitive acid blockers on human gut microbiota: a systematic review and meta-analysis

Background: Vonoprazan has been reported to exert more potent and long-lasting gastric acid inhibition than proton pump inhibitors, potentially leading to a greater impact on the gut microbiota. This study aimed to clarify changes in microbial diversity and bacterial composition after VPZ treatments. Methods: We searched from PubMed, Embase, WOS, Scopus, Cochrane Library, and ClinicalTrials.gov (all years up to May 2023). The primary outcomes were alpha and beta diversity, as well as differences in gut microbiota composition between before and after VPZ treatments. We performed a meta-analysis to uncover the potential changes in human gut microbiota among VPZ users by pooled mean difference (MD) with a 95% confidence interval (CI). The risk of bias was assessed using the ROBINS-I tool. Results: A total of 12 studies were included to compare differences before and after VPZ treatments. Compared with baseline, alpha diversity was significantly reduced after VPZ treatments and gradually returned to baseline with longer follow-up. At the phylum level, there was a decrease in the relative abundance of Firmicutes and Actinobacteria, while Bacteroidetes increased compared with baseline. At the genus level, we found a significant decrease in the relative abundance of Coprococcus and Bifidobacterium and a significant increase in the relative abundance of Bacteroides compared with those before treatment. In subgroup analyses according to country and participants, we found differences in microbial changes after VPZ treatments. Conclusion: Vonoprazan can affect the changes of gut microbiota, which may be potentially associated with its strong ability of acid inhibition. However, due to the large heterogeneity, further studies are required to validate these findings. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023412265.

Global research trends and hotspots of Helicobacter pylori eradication based on clinical trial registration platforms: A cross-sectional analysis

BACKGROUND

This study aimed to obtain an overview of clinical trials on Helicobacter pylori (H. pylori) eradication and analyze the global trends and hotspots in this field.

METHODS

We collected the data from clinical trials focused on H. pylori eradication in the primary clinical trial registries from 2000 to 2022 in the world. Then we analyzed the research trends and hotspots in H. pylori eradication regimens in different regions at different periods.

RESULTS

A total of 780 clinical trials were included, which were mainly conducted in Asia (682), followed by Europe (59), Africa (20), North America (16), South America (7), Oceania (2). The most active countries were China (343), Iran (140), South Korea (63), and Japan (73). "Bismuth-containing quadruple therapy (BQT)" was the most studied regimen (159, 20.38 %). Additionally, clinical trials focused on potassium-competitive acid blockers (P-CABs)-based therapy, probiotics, and high-dose dual therapy (HDDT) were constantly increasing. BQT received the most attention in China (26.53 %) and Iran (22.14 %), while it was tailored therapy in South Korea (23.29 %). P-CABs-based therapy was the main reseach hotspot in Japan (61.90 %).

CONCLUSION

How to eradicate H. pylori infection has been a heated research topic. BQT, P-CABs-based therapy, probiotics, and HDDT attracted the most attention in recent years.

Efficacy and Safety of Potassium-Competitive Acid Blockers Versus Proton Pump Inhibitors as Helicobacter pylori Eradication Therapy: A Meta-Analysis of Randomized Clinical Trials

Helicobacter pylori is a gram-negative bacterium that chronically infects the gastric epithelium. Potassium-competitive acid blockers (P-CABs) are a promising alternative, being more potent than standard proton pump inhibitors (PPIs). The meta-analysis followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Inclusion criteria were randomized controlled trials (RCTs) comparing P-CAB and PPI-based therapy, confirmed H. pylori infection, and measured eradication rates after at least four weeks. Subgroup analyses were conducted based on therapy type and trial location. Quality assessment used the Cochrane risk-of-bias tool, RoB 2.0, and statistical analysis was performed using ReviewManager (RevMan) 5.4 (2020; The Cochrane Collaboration, London, United Kingdom). A p-value of <0.05 is considered statistically significant. In the intention-to-treat (ITT) analysis, P-CABs demonstrated superior overall efficacy, consistently observed in the first-line treatment subgroup. However, no significant difference was found in the subgroup receiving salvage therapy. Another ITT subgroup analyzed the impact of geographical location, favoring P-CABs in the overall study population and the Japanese subgroup. However, no statistically significant differences were found in the subgroups of other countries. In the PPA, P-CABs showed superior efficacy overall, consistently seen in the first-line treatment subgroup. However, no significant difference was found in the subgroup receiving salvage eradication therapy. Another PPA subgroup analysis considered the geographical impact on eradication rates, revealing P-CABs as superior to PPIs in the overall study population and the Japanese subgroup, but not in other countries. No significant adverse event outcomes were observed. P-CAB-based triple therapy is more effective than PPI-based triple therapy as the primary treatment for H. pylori eradication, particularly in Japanese patients. Nevertheless, regarding salvage therapy, both treatments show comparable efficacy. Additionally, the tolerability of P-CAB-based and PPI-based triple therapy is similar, with a similar occurrence of adverse events.

Vonoprazan With Amoxicillin or Amoxicillin and Clarithromycin for the Treatment of Helicobacter pylori Infection

OBJECTIVES

To describe the pharmacology, efficacy, safety, and potential role of vonoprazan with amoxicillin or amoxicillin and clarithromycin for the treatment of Helicobacter pylori infection in adults.

DATA SOURCES

PubMed, Embase, Cochrane Library, and ClinicalTrials.gov were searched using the terms: (vonoprazan OR voquezna) AND ("H. pylori" OR "Helicobacter pylori") AND amoxicillin with no date limitations up to November 3, 2022.

STUDY SELECTION AND DATA EXTRACTION

Studies assessing the efficacy and safety of vonoprazan with amoxicillin and/or clarithromycin were included and divided into 3 groups based on different comparisons between treatment regimens used in each group.

DATA SYNTHESIS

Ten clinical trials and 17 observational studies were included. Vonoprazan-based therapy demonstrated greater acid inhibition and similar or higher efficacy than proton-pump inhibitor (PPI)-based therapy in treatment-naïve patients and with clarithromycin-resistant infections.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Proton-pump inhibitor-based therapies have not reached the desired successful eradication rate of 90% for H. pylori infection. Vonoprazan-based therapies being at least as effective as PPI-based therapies offer an alternative for patients with H. pylori infection.

CONCLUSION

Vonoprazan-based therapies were effective and well tolerated for the treatment of H. pylori infection in adults. These regimens provide an important alternative with prolonged acid inhibition, lower potential for CYP2C19 polymorphism, and at least comparable efficacy and safety versus PPI-based therapies in patients with H. pylori infections. Thus, vonoprazan-based therapy should be considered for certain patients, for example, those with failure to PPI-based treatments.

Targeting ATP12A, a Nongastric Proton Pump α Subunit, for Idiopathic Pulmonary Fibrosis Treatment

Idiopathic pulmonary fibrosis (IPF) is a pathological condition of unknown etiology that results from injury to the lung and an ensuing fibrotic response that leads to the thickening of the alveolar walls and obliteration of the alveolar space. The pathogenesis is not clear, and there are currently no effective therapies for IPF. Small airway disease and mucus accumulation are prominent features in IPF lungs, similar to cystic fibrosis lung disease. The ATP12A gene encodes the α-subunit of the nongastric H+, K+-ATPase, which functions to acidify the airway surface fluid and impairs mucociliary transport function in patients with cystic fibrosis. It is hypothesized that the ATP12A protein may play a role in the pathogenesis of IPF. The authors' studies demonstrate that ATP12A protein is overexpressed in distal small airways from the lungs of patients with IPF compared with normal human lungs. In addition, overexpression of the ATP12A protein in mouse lungs worsened bleomycin induced experimental pulmonary fibrosis. This was prevented by a potassium competitive proton pump blocker, vonoprazan. These data support the concept that the ATP12A protein plays an important role in the pathogenesis of lung fibrosis. Inhibition of the ATP12A protein has potential as a novel therapeutic strategy in IPF treatment.

Discovery of novel benzimidazole derivatives as potent potassium-competitive acid blockers for the treatment of acid-related diseases

H⁺, K⁺-ATPase, as the most critical enzyme in gastric acid secretion, has long been an attractive target for the treatment of acid-related diseases. In this study, a series of benzimidazole derivatives were designed and synthesized through conformational restriction and skeleton hopping strategies by using vonoprazan as the lead compound. Among them, compounds A12 (IC₅₀ = 9.32 μM) and A18 (IC₅₀ = 5.83 μM) showed better inhibition at the enzyme level. In addition, gastric acid secretion inhibition was assessed in vivo, and the results showed that A12 and A18 significantly inhibited basal gastric acid secretion, 2-deoxy-d-glucose (2DG) stimulated gastric acid secretion and histamine-stimulated gastric acid secretion. In further in vitro metabolic experiments, A12 and A18 demonstrated excellent stability and low toxicity. Pharmacokinetic studies showed that the p.o. and i.v. half-lives of A18 were 3.21 h and 8.67 ± 1.15 h, respectively. In summary, A18 might be a novel and effective potassium-competitive acid blocker, and this study provides strong support for it use in the treatment of acid-related diseases.

The efficacy and mechanism of vonoprazan-containing triple therapy in the eradication of Helicobacter pylori

Purpose: Vonoprazan (VPZ) produces a strong acid-inhibitory effect, which can potentially eradicate Helicobacter Pylori (H. pylori). We aimed to assess whether a 14-day VPZ-containing triple therapy was safe and effective in the Chinese population and the potential mechanism. Methods: Enrolled patients confirmed to be infected with H. pylori were randomly divided into four groups: VPZ + doxycycline + furazolidone, VPZ + doxycycline + amoxicillin, esomeprazole (EPZ) + bismuth + doxycycline + furazolidone, and EPZ + colloidal bismuth + doxycycline + amoxicillin for 14 days. The eradication rate, medication adherence, and incidence of adverse events (AEs) were evaluated. Inhibition of H. pylori by VPZ and EPZ in vitro was assessed. H. pylori treated with appropriate concentrations of VPZ and EPZ were sequenced by transcriptome analysis to explore the antibacterial mechanism. Results: A higher eradication rate were observed in VPZ-containing triple therapy. No obvious differences were observed in medication adherence or the incidence of AEs. VPZ had no direct inhibitory effect on H. pylori, whereas EPZ directly inhibited H. pylori may through downregulated genes related to the ribosome. Conclusion: In the Chinese population, 14-day VPZ-containing triple therapy was safe and more effective and can be used clinically as first-line H. pylori treatment. Clinical Trial Registration: ClinicalTrials.gov, identifier NCT05097846.

Quadruple therapy with vonoprazan 20 mg daily as a first-line treatment for Helicobacter pylori infection: A single-center, open-label, noninferiority, randomized controlled trial

BACKGROUND

Although vonoprazan has been proven to be a highly potent drug for Helicobacter pylori eradication, there have been no randomized trials comparing the effectiveness of regimens containing vonoprazan 20 mg daily with alternative standard strategies. We aimed to assess the efficacy, tolerance, and cost-effectiveness of quadruple therapy with vonoprazan 20 mg daily as a first-line therapy for H. pylori eradication.

MATERIALS AND METHODS

We conducted a single-center, open-label, noninferiority, randomized controlled study in Zhejiang, China. Treatment-naive H. pylori-positive participants (n = 234) were randomly assigned to three groups in a 1:1:1 ratio: vonoprazan 20 mg daily with amoxicillin 1000 mg, furazolidone 100 mg and colloidal bismuth 200 mg each given twice a day for 10 days (V10) or 14 days (V14), or esomeprazole 20 mg with amoxicillin 1000 mg, furazolidone 100 mg and colloidal bismuth 200 mg each given twice a day for 14 days (E14). The primary endpoint was the eradication rates in each group. The secondary endpoints were the incidence of adverse events (AEs) and compliance.

RESULTS

The eradication rates in the V10, V14 and E14 groups were 96.2% (89.2-99.2%), 94.9% (87.4-98.6%), and 93.6% (85.7-97.9%) in the intention-to-treat analysis, and 98.6% (92.7-100.0%), 97.4% (90.8-99.7%), and 94.8% (87.2-98.6%) in the per-protocol analysis, respectively. Quadruple therapy with vonoprazan 20 mg daily was noninferior to the esomeprazole-based regimen (Farrington and Manning test: margin 10%, significance level 2.5%). The adverse event rates were 12.8% versus 3.8% versus 6.4% in the V10, V14, and E14 groups, respectively. All regimens were well tolerated without significant differences (p = 0.096). The cost-effectiveness ratio was 1.32, 1.88, and 3.06 for the V10, V14, and E14 groups in the intention-to-treat analysis, respectively. (NCT04907747).

CONCLUSIONS

Vonoprazan (20 mg daily) was as effective as esomeprazole (20 mg twice a day) in quadruple therapies for the eradication of H. pylori, was more economical, and was well tolerated. In addition, the 10-day regimen of vonoprazan (20 mg daily) was comparable to the 14-day regimen.

Vonoprazan Versus Lansoprazole for Healing and Maintenance of Healing of Erosive Esophagitis: A Randomized Trial

BACKGROUND & AIMS

For decades, proton pump inhibitors (PPIs) have been the mainstay of treatment for erosive esophagitis. The potassium-competitive acid blocker vonoprazan provides more potent acid inhibition than PPIs, but data on its efficacy for erosive esophagitis are limited.

METHODS

Adults with erosive esophagitis were randomized to once-daily vonoprazan, 20 mg, or lansoprazole, 30 mg, for up to 8 weeks. Patients with healing were rerandomized to once-daily vonoprazan, 10 mg, vonoprazan, 20 mg, or lansoprazole, 15 mg, for 24 weeks. Primary end points, percentage with healing by week 8 endoscopy, and maintenance of healing at week 24 endoscopy, were assessed in noninferiority comparisons (noninferiority margins, 10%), with superiority analyses prespecified if noninferiority was demonstrated. Analyses of primary and secondary end points were performed using fixed-sequence testing procedures.

RESULTS

Among 1024 patients in the healing phase, vonoprazan was noninferior to lansoprazole in the primary analysis and superior on the exploratory analysis of healing (92.9 vs 84.6%; difference, 8.3%; 95% confidence interval [CI], 4.5%-12.2%). Secondary analyses showed vonoprazan was noninferior in heartburn-free days (difference, 2.7%; 95% CI, -1.6% to 7.0%), and superior in healing Los Angeles Classification Grade C/D esophagitis at week 2 (difference, 17.6%; 95% CI, 7.4%-27.4%). Among 878 patients in the maintenance phase, vonoprazan was noninferior to lansoprazole in the primary analysis and superior on the secondary analysis of maintenance of healing (20 mg vs lansoprazole: difference, 8.7%; 95% CI, 1.8%-15.5%; 10 mg vs lansoprazole: difference, 7.2%; 95% CI, 0.2%-14.1%) and secondary analysis of maintenance of healing Grade C/D esophagitis (20 mg vs lansoprazole: difference, 15.7%; 95% CI, 2.5%-28.4%; 10 mg vs lansoprazole: difference, 13.3%; 95% CI, 0.02%-26.1%).

CONCLUSIONS

Vonoprazan was noninferior and superior to the PPI lansoprazole in healing and maintenance of healing of erosive esophagitis. This benefit was seen predominantly in more severe erosive esophagitis. (ClinicalTrials.gov: NCT04124926).

Long-term vonoprazan administration causes gastric fundic gland-type hyperplastic polyps and chronic bleeding

A patient experienced gastric fundic gland-type hyperplastic polyps, consisting of foveolar epithelium and parietal cells, complicated with chronic bleeding due to long-term treatment with vonoprazan. The patient had progressive anemia, probably caused by bleeding from the polyps. After switching from vonoprazan to a histamine-2 (H2) receptor antagonist, the polyps markedly shrank and the anemia improved. Vonoprazan can produce reversible hyperplastic polyps and anemia. In case of anemia in patients receiving long-term vonoprazan, it is important to consider drug cessation or change to an H2 blocker.

Efficacy, safety and cost-effectiveness of vonoprazan vs Proton Pump Inhibitors in reflux disorders and H. pylori eradication: A literature review

Gastroesophageal reflux disease (GERD) is one of the most prevalent conditions worldwide and is conventionally treated by proton pump inhibitor therapy. However, around 40% of people have reported some form of resistance to this therapy. Vonoprazan has recently been approved for the treatment of GERD. Literature was searched on PubMed, Google Scholar, Embase and Medline. Inclusion criteria were 1) Human subjects; 2) papers published in English language; 3) study types that are RCTs. In pre-clinical studies, VPZ was unaffected by changes in pH, making it 1.2-2 times more potent than PPI, both in-vivo and in-vitro. In studies involving GERD, several RCTs proved higher efficacy of VPZ than conventional PPI. RCTs on patients affected by H. Pylori showed a higher efficacy than VPZ (95.8%) as compared to PPI (69.6%). In another RCT, adverse effects including diarrhea, nausea and body rash were observed in 32.7% of the people taking VPZ as compared to 40.5% of the people taking PPI. VPZ was shown to be much more cost effective as compared to PPI. This article concludes that VPZ is superior to PPI in terms of efficacy, safety and cost-effectiveness in reflux disorders and H. pylori eradication. Hence, use of vonoprazan should be preferred over conventional PPIs in these disorders. As most of the research was conducted in Japan, studies should be carried out in different regions of the world to explore if these results are extrapolated in those regions. Research is also needed to explore the efficiency of VPZ in scenarios of PPI resistance.

Efficacy and safety of potassium-competitive acid blockers versus proton pump inhibitors as Helicobacter pylori eradication therapy: a meta-analysis of randomized clinical trials

BACKGROUND AND AIMS

Potassium-Competitive Acid Blockers (P-CABs) have been used in Helicobacter pylori (H. pylori) eradication therapies in recent years. However, the efficacy and safety of P-CABs compared to Proton-Pump Inhibitors (PPIs) in this setting remain controversial.

METHODS

The efficacy and safety of P-CABs and PPIs for H. pylori eradication were compared in a meta-analysis based on a systematic literature search of major electronic databases for relevant Randomized Controlled Trials (RCTs).

RESULTS

Seven studies and 1,168 patients were included. The pooled eradication rate determined by Intention-To-Treat (ITT) analysis was 90.2% for P-CAB-based and 75.5% for PPI-based triple therapy (pooled RR [95% CI] = 1.17 [1.08-1.28], p < 0.001). The Per-Protocol (PP) analysis also demonstrated significant superiority of P-CABs (pooled eradication rate = 92.4% vs. 77.8%; pooled RR [95% CI] = 1.14 [1.03-1.26], p < 0.01). In a subgroup evaluation, P-CABs were significantly better than PPIs as a first-line eradication therapy, in both the ITT analysis (pooled eradication rate = 91.8% vs. 76.4%; pooled RR [95% CI] = 1.18 [1.10-1.28], p < 0.0001) and the PP analysis (pooled eradication rate = 93.0% vs. 78.6%; pooled RR [95% CI] = 1.13 [1.02-1.26], p < 0.05). However, P-CABs were not superior to PPIs when administered as salvage therapy, as determined in the ITT (75.0% vs. 66.0%, pooled RR [95% CI] = 1.11 [0.69-1.78], p = 0.66) and PP (85.7% vs. 70.0%, pooled RR [95% CI] = 1.20 [0.82-1.75], p = 0.34) analyses. In a subgroup analysis limited to Japanese patients, both the ITT analysis (pooled eradication rate = 89.6% vs. 73.9%; RR [95% CI] = 1.21 [1.14-1.29], p < 0.01) and the PP analysis (pooled eradication rate = 92.0% vs. 75.7%; RR [95% CI] = 1.18 [1.06-1.32], p < 0.01) showed that P-CABs were significantly superior compared to PPIs as triple eradication therapy. However, in the subgroup analysis of patients from other countries, there was no significant difference in either the ITT analysis (pooled eradication rate = 93.8% vs. 85.2%; RR [95% CI] = 1.10 [0.99-1.22], p = 0.07) or PP analysis (pooled eradication rate = 95.0% vs. 90.8%; RR [95% CI] = 1.05 [0.98-1.14], p = 0.17). The incidence of adverse events associated with the two regimens did not significantly differ (P-CABs vs. PPIs: 33.6% vs. 40.0%; RR [95% CI] = 0.84 [0.71‒1.00], p = 0.05). The incidence of serious adverse events and dropout rate due to adverse events also did not differ (p = 0.44 and p = 0.67, respectively).

CONCLUSIONS

The efficacy of P-CAB-based triple therapy is superior to that of PPI-based triple therapy as a first-line approach to H. pylori eradication, particularly in Japanese patients. As salvage therapy, the efficacy of the two treatments did not significantly differ. The tolerability of P-CAB-based and PPI-based triple therapy was comparable, as was the incidence of adverse events.

Pharmacodynamics and Pharmacokinetics of the Potassium-Competitive Acid Blocker Vonoprazan and the Proton Pump Inhibitor Lansoprazole in US Subjects

INTRODUCTION

We assessed pharmacodynamics and pharmacokinetics of a potassium-competitive acid blocker and proton pump inhibitor in US subjects.

METHODS

Healthy adults were randomized to 7-day periods of vonoprazan 20 mg once daily followed by lansoprazole 30 mg once daily or the reverse order, separated by ≥ 7 days of washout.

RESULTS

Vonoprazan (N = 40) had higher proportions of 24-hour periods with intragastric pH > 4 than lansoprazole (N = 41,38) on day 1 (62.4% vs 22.6%, P < 0.0001) and day 7 (87.8% vs 42.3%, P < 0.0001). Separation in pH started ∼2.5 hours after the first dose.

DISCUSSION

Vonoprazan provided more rapid and potent inhibition of intragastric acidity than lansoprazole in US subjects.

Network Meta-analysis Comparing Vonoprazan and Proton Pump Inhibitors for Heartburn Symptoms in Erosive Esophagitis

GOALS

This systematic review and network meta-analysis aimed to assess the relative efficacy of vonoprazan and proton pump inhibitors (PPIs) on early heartburn symptom resolution in patients with erosive esophagitis.

BACKGROUND

Limited available data directly compare the efficacy of vonoprazan, a first-in-class potassium-competitive acid blocker, with PPIs in erosive esophagitis.

STUDY

We conducted a systematic literature review (in MEDLINE and CENTRAL) and subsequent network meta-analysis according to Cochrane and PRISMA guidelines. Double-blind, randomized controlled trials in adults with erosive esophagitis treated with vonoprazan or a PPI were included in the analysis. Primary outcomes were heartburn symptom resolution rate on Day 1 and Day 7. The study was performed with all available data, using a random effects model within a Bayesian framework.

RESULTS

Overall, 10 randomized controlled trials were included in the network meta-analysis. For heartburn resolution rate on Day 1 (9 of 10 trials), vonoprazan 20 mg once daily (QD) was superior to placebo (median odds ratio=16.75, 95% credible interval: 2.16-207.80). Point estimates numerically favored vonoprazan 20 mg QD over other comparators. For heartburn resolution rate on Day 7 (10 of 10 trials), vonoprazan 20 mg QD was superior to placebo and other comparators except rabeprazole 20 mg QD. Point estimates numerically favored vonoprazan 20 mg QD over rabeprazole 20 mg QD.

CONCLUSIONS

In this study, vonoprazan 20 mg QD was equally effective in heartburn resolution on Day 1, and equally or more effective on Day 7 versus PPIs in adults with erosive esophagitis.

Novel Potassium-Competitive Acid Blocker, Tegoprazan, Protects Against Colitis by Improving Gut Barrier Function

Inflammatory bowel disease (IBD) is a chronic immune-mediated disorder characterized by prolonged inflammation of the gastrointestinal tract. IBD can result from gut barrier dysfunction, altered gut microbiota, and abnormal intestinal immunity induced by environmental factors in genetically susceptible individuals. Proton pump inhibitors (PPIs) such as rabeprazole are frequently employed for gastric acid inhibition. However, long-term PPI administration can alter the intestinal microbiome composition, possibly worsening IBD severity. The present study revealed that tegoprazan, a potassium-competitive acid blocker, significantly improved colitis in mice and enhanced the intestinal epithelial barrier function. Tegoprazan alleviated gut microbiota dysbiosis and enhanced the growth of Bacteroides vulgatus. In turn, B. vulgatus alleviated intestinal inflammation by inhibiting epithelial adhesion of pathogenic bacteria. Unlike rabeprazole, tegoprazan did not induce gut dysbiosis. Our findings provide novel insights into the potential role of tegoprazan as an intestinal protectant for IBD and as a therapeutic agent for gastric acid-related diseases.

An update of pharmacology, efficacy, and safety of vonoprazan in acid-related disorders

INTRODUCTION

Patients with acid-related disorders (ARDs) of the upper digestive tract remain highly prevalent and need to be continuously investigated to improve their management.

AREAS COVERED

This review provides a summary of the most recent advancements in the treatment of ARDs with particular focus on the new drugs available to overcome the unmet needs of traditional therapies.

EXPERT OPINION

Proton pump inhibitors remain the best therapy in treating ARDs, but a consistent proportion of these patients continues to present mucosal lesions or to experience symptoms despite treatment. These cases pertain mainly to the most severe forms of erosive esophagitis or to non-erosive reflux disease. Also, the increasing rate of patients with H. pylori infection not responding to eradication therapy represents a difficult clinical condition. The recent advent of a new class of antisecretory drugs, such as the potassium competitive acid blockers and, among them the most studied vonoprazan, which are characterized by a better pharmacological profile than PPIs (rapid onset of action, longer lasting acid suppression, control of nocturnal acidity), has the potential to overcome the above-mentioned unmet needs. More research should be done to assess their efficacy in Western populations and their safety in patients treated in the long term.

Efficacy of Vonoprazan for Refractory Reflux Esophagitis after Esophagectomy

BACKGROUND

Refractory reflux esophagitis (RRE), unresponsive to conventional proton-pump inhibitors (PPIs), is a complication in esophagectomy with gastric pull-up. Vonoprazan (VPZ), a novel potassium-competitive acid blocker, has been available in Japan since 2015. Here, we investigated the efficacy of VPZ on PPI-resistant RRE after esophagectomy with gastric pull-up.

METHODS

This was a single-center retrospective study. We used the revised Los Angeles (r-LA) classification based on the Los Angeles classification and the modified Los Angeles classification to evaluate abnormal forms of mucosal breaks such as lateral spreading consistently. Patients who underwent esophagectomy with gastric pull-up and had RRE grade B-D as per the r-LA classification, despite using standard-dose PPIs or double dose of rabeprazole, were included. Sixteen patients who switched to VPZ (20 mg/day) and 14 patients who continued PPIs were assigned to the VPZ and PPI groups, respectively. Endoscopic observations were reviewed by 3 endoscopists using the r-LA classification to ensure consistent diagnosis, while the treatment arm and patient information were blinded to evaluators. We defined mucosal breaks that improved by at least one grade after treatment as improved mucosa and recovery to grade M or N as mucosal healing.

RESULTS

The percentage of patients with improved mucosa in the VPZ and PPI groups was 81.3 and 14.3%, respectively (p < 0.001). The rate of mucosal healing was 68.8 and 7.1%, respectively (p = 0.001).

CONCLUSION

VPZ significantly improved PPI-resistant RRE after esophagectomy with gastric pull-up.

Blood concentrations of tacrolimus upon conversion from rabeprazole to vonoprazan in renal transplant recipients: Correlation with cytochrome P450 gene polymorphisms

We evaluated the impact of vonoprazan on blood concentrations of tacrolimus via a retrospective analysis of 52 renal transplant recipients who took tacrolimus and converted from rabeprazole to vonoprazan between August 2018 and September 2019. We compared tacrolimus trough levels upon conversion among groups that were classified based on cytochrome P450 (CYP) gene polymorphisms. CYP3A5 groups were heterozygous or homozygous for CYP3A5∗1 and CYP3A5∗3 alleles. CYP2C19 genotypes were classified as extensive (∗1/∗1), intermediate (∗1/∗2 and ∗1/∗3) or poor metabolizers (∗2/∗2, ∗2/∗3 and ∗3/∗3). Tacrolimus trough levels increased only 0.3 ng/mL upon conversion in the CYP3A5∗3/∗3 group: 5.8 [3.4-7.2] vs 6.1 [3.8-7.9]; p = 0.06. No statistically significance changes in tacrolimus levels also occurred in the CYP3A5∗1/∗1 or CYP3A5∗1/∗3 groups. Subgroup analyses of CYP3A5∗3/∗3 demonstrated low changes for all three CYP2C19 subgroups: 5.2 [4.3-6.5] vs 6.2 [4.3-7.9]; p = 0.07, 6.1 [3.4-7.2] vs 6.7 [4.6-7.9]; p = 0.12 and 5.4 [3.6-6.5] vs 4.7 [3.8-6.3]; p = 1.00, respectively. Conversion to vonoprazan thus resulted in little increase of tacrolimus trough levels, even in the group predicted to be most susceptible (CYP3A5∗3/∗3 and 2C19∗1/∗1), thus supporting the safety of concomitant use of vonoprazan with tacrolimus.

The Potential Benefits of Vonoprazan as Helicobacter pylori Infection Therapy

Helicobacter pylori infection is a severe global health problem that is closely associated with acid-related diseases and gastric malignancies. Eradicating H. pylori is strongly recommended for lowering peptic ulcer recurrence and preventing gastric cancer. The current approved H. pylori eradication regimen combines a proton pump inhibitor (PPI) with two antibiotics. Unfortunately, this regimen failed to meet expectations mostly due to antibiotic resistance and insufficient gastric acid suppression. Vonoprazan, a novel potassium-competitive acid blocker, showed promising results as a PPI replacement. Vonoprazan inhibits gastric acid secretion by acting as a reversible competitive inhibitor against potassium ions and forming disulfide bonds with the cysteine molecule of H⁺/K⁺-ATPase. Vonoprazan has superior pharmacological characteristics over PPI, such as no requirement for acid activation, stability in acidic conditions, shorter optimum acid suppression period, and resistance to cytochrome P (CYP)2C19 polymorphism. Several comparative randomized controlled trials and meta-analyses revealed the superiority of vonoprazan in eradicating H. pylori, notably the resistant strains. The adverse effect caused by vonoprazan is long-term acid suppression that may induce elevated gastrin serum, hypochlorhydria, and malabsorption. All vonoprazan studies have only been conducted in Japan. Further studies outside Japan are necessary for universally conclusive results.

Proton pump inhibitors for chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a common and progressive disease characterised by chronic cough, airflow limitation and recurrent exacerbations. Since COPD exacerbations are linked to rising mortality and reduced quality of life, the condition poses a substantial burden on individuals, society and the healthcare system. Effective management of COPD exacerbations that includes treatment of related conditions in people with COPD is thus recognised as a relevant clinical question and an important research topic. Gastroesophageal reflux disease (GERD) is a known comorbidity of COPD, and pulmonary microaspiration of gastric acid is thought to be a possible cause of COPD exacerbations. Therefore, reducing gastric acid secretion may lead to a reduction in COPD exacerbations. Proton pump inhibitors (PPIs) are one of the most commonly prescribed medications and are recommended as first-line therapy for people with GERD because of their inhibitory effects on gastric acid secretion. Treatment with PPIs may present a viable treatment option for people with COPD.

OBJECTIVES

To evaluate the efficacy and safety of PPI administration for people with COPD, focusing on COPD-specific outcomes.

SEARCH METHODS

We searched the Cochrane Airways Register of Trials and conventional clinical trial registers from inception to 22 May 2020. We also screened bibliographies of relevant studies.

SELECTION CRITERIA

Parallel-group and cluster-randomised controlled trials (RCTs) that compared oral PPIs versus placebo, usual care or low-dose PPIs in adults with COPD were eligible for inclusion. We excluded cross-over RCTs, as well as studies with a duration of less than two months.

DATA COLLECTION AND ANALYSIS

Two independent review authors screened search results, selected studies for inclusion, extracted study characteristics and outcome data, and assessed risk of bias according to standard Cochrane methodology. We resolved discrepancies by involving a third review author. Primary outcomes of interest were COPD exacerbations, pneumonia and other serious adverse events. Secondary outcomes were quality of life, lung function test indices, acute respiratory infections and disease-specific adverse events. We extracted data on these outcome measures and entered into them into Review Manager software for analysis.

MAIN RESULTS

The search identified 99 records, and we included one multicentre RCT that randomised 103 adults with COPD. The 12-month RCT compared an oral PPI (lansoprazole) and usual care versus usual care alone. It was conducted at one tertiary care hospital and three secondary care hospitals in Japan. This study recruited participants with a mean age of 75 years, and excluded people with symptoms or history of GERD. No placebo was used in the usual care arm. Among the primary and secondary outcomes of this review, the study only reported data on COPD exacerbations and acute respiratory infections (the common cold). As we only included one study, we could not conduct a meta-analysis. The included study reported that 12 of the 50 people on lansoprazole had at least one exacerbation over a year, compared to 26 out of 50 on usual care (risk ratio 0.46, 95% CI 0.26 to 0.81). The frequency of COPD exacerbations per person in a year was also lower in the PPI plus usual care group than in the usual care alone group（0.34 ± 0.72 vs 1.18 ± 1.40; P < 0.001). The number of people with at least one cold over the year was similar in both groups: 26 people on lansoprazole and 27 people in the usual care group. We judged the evidence to be of low to very low certainty, according to GRADE criteria. The study reported no data on pneumonia and other serious adverse events, quality of life, lung function test indices or disease-specific adverse events. The risk of bias was largely low or unclear for the majority of domains, though the performance bias was a high risk, as the study was not blinded.

AUTHORS' CONCLUSIONS

Evidence identified by this review is insufficient to determine whether treatment with PPIs is a potential option for COPD. The sample size of the included trial is small, and the evidence is low to very low-certainty. The efficacy and safety profile of PPIs for people with COPD remains uncertain. Future large-scale, high-quality studies are warranted, which investigate major clinical outcomes such as COPD exacerbation rate, serious adverse events and quality of life.

Best Helicobacter pylori Eradication Strategy in the Era of Antibiotic Resistance

Antibiotic resistance is the major reason for Helicobacter pylori treatment failure, and the increasing frequency of antibiotic resistance is a challenge for clinicians. Resistance to clarithromycin and metronidazole is a particular problem. The standard triple therapy (proton pump inhibitor, amoxicillin, and clarithromycin) is no longer appropriate as the first-line treatment in most areas. Recent guidelines for the treatment of H. pylori infection recommend a quadruple regimen (bismuth or non-bismuth) as the first-line therapy. This treatment strategy is effective for areas with high resistance to clarithromycin or metronidazole, but the resistance rate inevitably increases as a result of prolonged therapy with multiple antibiotics. Novel potassium-competitive acid blocker-based therapy may be effective, but the data are limited. Tailored therapy based on antimicrobial susceptibility test results is ideal. This review discussed the current important regimens for H. pylori treatment and the optimum H. pylori eradication strategy.

Efficacy of Vonoprazan for Helicobacter pylori Eradication

Helicobacter pylori can infect the gastric mucosa and cause chronic inflammation, resulting in various diseases, including gastric cancer. Eradication of H. pylori in all infected subjects is recommended; however, the number of H. pylori strains with antibiotic resistance has increased, and the eradication rate has decreased. Vonoprazan, a potassium-competitive acid blocker, produces a stronger acid-inhibitory effect than proton pump inhibitors (PPIs). The H. pylori eradication rate with vonoprazan was found to be higher than that with PPIs. The H. pylori eradication rate with vonoprazan-based triple therapy (vonoprazan, amoxicillin, and clarithromycin) was approximately 90% and had an incidence of adverse events similar to that of PPIs. We review the current situation of H. pylori eradication in Japan, the first country in which vonoprazan was made available.

Optimizing proton pump inhibitors in Helicobacter pylori treatment: Old and new tricks to improve effectiveness

The survival and replication cycle of Helicobacter pylori (H. pylori) is strictly dependant on intragastric pH, since H. pylori enters replicative phase at an almost neutral pH (6-7), while at acid pH (3-6) it turns into its coccoid form, which is resistant to antibiotics. On these bases, it is crucial to increase intragastric pH by proton pump inhibitors (PPIs) when an antibiotic-based eradicating therapy needs to be administered. Therefore, several tricks need to be used to optimize eradication rate of different regimens. The administration of the highest dose as possible of PPI, by doubling or increasing the number of pills/day, has shown to be able to improve therapeutic outcome and has often proposed in rescue therapies, even if specific trials have not been performed. A pre-treatment with PPI before starting antibiotics does not seem to be effective, therefore it is discouraged. However, the choice of PPI molecule could have a certain weight, since second-generation substances (esomeprazole, rabeprazole) are likely more effective than those of first generation (omeprazole, lansoprazole). A possible explanation is due to their metabolism, which has been proven to be less dependent on cytochrome P450 (CYP) 2C19 genetic variables. Finally, vonoprazan, a competitive inhibitor of H+/K+-ATPase present on luminal membrane of gastric parietal cells has shown the highest efficacy, due to both its highest acid inhibition power and rapid pharmacologic effect. However current data come only from Eastern Asia, therefore its strong power needs to be confirmed outside this geographic area in Western countries as well as related to the local different antibiotic resistance rates.

Effects of Tegoprazan, a Novel Potassium-Competitive Acid Blocker, on Rat Models of Gastric Acid-Related Disease

Tegoprazan, a novel potassium-competitive acid blocker (P-CAB), is a next-generation therapeutics developed for the treatment of acid-related gastrointestinal diseases such as gastroesophageal reflux disease (GERD) and peptic ulcers. In the present study, the in vitro and in vivo pharmacological properties of tegoprazan were compared with those of esomeprazole, a representative proton pump inhibitor. In vitro enzyme assays were performed using ion-leaky vesicles containing gastric H+/K+-ATPases isolated from pigs. The in vivo efficacies of tegoprazan were evaluated in rat models of GERD and peptic ulcer. Tegoprazan inhibited the activity of porcine H+/K+-ATPase with an IC50 value of 0.53 μM in a reversible manner, whereas esomeprazole showed weak and irreversible inhibition with an IC50 value of 42.52 μM. In a GERD model, tegoprazan showed dose-dependent efficacy in inhibiting esophageal injury and gastric acid secretion with an ED50 of 2.0 mg/kg, which was 15-fold more potent than that of esomeprazole. In peptic ulcer models, tegoprazan exhibited superior antiulcer activity compared with esomeprazole. The ED50 of tegoprazan in the naproxen-, ethanol-, and water-immersion restraint stress-induced peptic ulcer models were 0.1, 1.4, and 0.1 mg/kg, respectively. In the acetic acid-induced peptic ulcer model, the curative ratio of tegoprazan at 10 mg/kg was higher than that of esomeprazole at 30 mg/kg (44.2% vs. 32.7%, respectively), after 5 days of repeated oral administration. Thus, tegoprazan is a novel P-CAB that shows potent and reversible inhibition of gastric H+/K+-ATPase and may provide stronger efficacy compared with previous proton pump inhibitors.

[Gastroesophageal Reflux Disease]

Gastroesophageal reflux disease (GERD) is a condition that develops when reflux of stomach contents causes troublesome symptoms and/or complications. The prevalence of GERD is increasing worldwide and in Asia-Pacific. The latest Korean guidelines for GERD were published in 2012, and several international guidelines and consensus statements for the management of GERD have also been recently published. Here, we review these guidelines and consensus statements in order to provide a better understanding of the diagnosis and treatment of GERD.

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.

Role of Vonoprazan in Helicobacter pylori Eradication Therapy in Japan

Complete eradication of Helicobacter pylori is important for preventing the development of gastric cancer. The outcome of H. pylori eradication therapy is mainly dependent on bacterial susceptibility to antimicrobial agents and potent neutralization of intragastric pH across 24 h, especially when using acid-sensitive antimicrobial agents such as clarithromycin (CLR), amoxicillin and sitafloxacin. However, conventional regimens comprising twice-daily doses (bid) of proton pump inhibitors (PPIs) are generally insufficient for maintaining the required gastric acid secretion for 24 h for successful eradication in all H. pylori-positive patients. Further, the increasing prevalence of CLR-resistant strains with each year has led to a decrease in eradication rates of first-line PPI- and CLR-containing therapies in developed countries, including Japan. In 2015, the potassium-competitive acid blocker vonoprazan (VPZ) became clinically available in Japan. VPZ competitively inhibits H+/K+-ATPase activity more potently than PPIs (e.g., omeprazole, lansoprazole, rabeprazole, pantoprazole, and esomeprazole). Therefore, a VPZ-containing H. pylori eradication regimen is expected to increase the eradication rate compared with conventional regimens containing a standard dose of PPI. In fact, a recent meta-analysis that investigated the efficacy of first-line eradication therapy showed that a VPZ-containing regimen achieved a higher eradication rate than a PPI-containing regimen. While the Maastricht V/Florence Consensus Report recommends selecting a bismuth or non-bismuth quadruple therapy and concomitant therapy for patients living in areas with high prevalence of CLR resistance, a VPZ-containing regimen demonstrates effectiveness for patients infected with CLR-resistant strains and patients living in areas where the prevalence of CLR-resistant strains is >15%. As a next step, studies are needed to determine the factors affecting the clinical outcome of VPZ-containing therapy and optimal VPZ-containing alternative regimens for tailored treatments. In this review, we summarize the advantages and disadvantages of VPZ in H. pylori eradication therapy.

Uncovering abnormal changes in logP after fluorination using molecular dynamics simulations

The fluorination-induced changes in the logP (1-octanol/water partition coefficient) of ligands were examined by molecular dynamics simulations. The protocol and force field parameters were first evaluated by calculating the logP values for n-alkanes, and their monofluorinated and monochlorinated analogs. Then, the logP values of several test sets (1-butanol, 3-propyl-1H-indole, and analogs fluorinated at the terminal methyl group) were calculated. The calculated results agree well with experiment, and the root mean square error values are 0.61 and 0.68 log units for the GAFF and GAFF2 force fields, respectively. Finally, the logP estimation was extended to a drug molecule, TAK-438, for which fluorination-induced abnormal logP reduction has been observed experimentally. This abnormal change was qualitatively reproduced by the molecular dynamics simulations. We found that the abnormal logP reduction can be mainly attributed to the effect of fluorination-induced dipole change. Our results suggest that molecular simulation is a useful strategy to predict the fluorination-induced change in logP for drug discovery applications.

[New Helicobacter pylori Eradication Therapies]

While the prevalence of Helicobacter pylori (H. pylori) infection is decreasing in Korea, the incidence of gastric cancer remains high, emphasizing the importance of H. pylori eradication. A new treatment strategy is needed as the eradication rate with standard triple therapy, which is currently the standard first-line regimen for H. pylori infection, has decreased below the optimum level. The major cause of eradication failure is increased antibiotic resistance. Sequential, concurrent, and hybrid therapies that include clarithromycin produce higher eradication rates than conventional standard triple therapy. However, the effectiveness of these treatments is limited in regions where the resistance rate to various antibiotics is high. Bismuth quadruple therapy is another alternative therapy, but again the eradication rate is not sufficiently high. Tailored therapy based on individual characteristics, including antibiotic susceptibility, may be ideal, but there are several limitations for clinical application and further research is needed. New potassium-competitive acid blocker-based therapies could emerge as effective alternatives in the near future. A consensus is needed to establish a strategy for applying new eradication therapies in Korea.

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.

Severity of gastric mucosal atrophy affects the healing speed of post-endoscopic submucosal dissection ulcers

AIM

To investigate factors associated with the healing of endoscopic submucosal dissection (ESD)-induced ulcers.

METHODS

We enrolled 132 patients with gastric tumors scheduled for ESD. Following ESD, patients were treated with daily lansoprazole 30 mg or vonoprazan 20 mg. Ulcer size was endoscopically measured on the day after ESD and at 4 and 8 wk. The gastric mucosa was endoscopically graded according to the Kyoto gastritis scoring system. We assessed the number of patients with and without a 90% reduction in ulcer area at 4 wk post-ESD and scar formation at 8 wk, and looked for risk factors for slower healing.

RESULTS

The mean size of gastric tumors and post-ESD ulcers was 17.4 ± 12.1 mm and 32.9 ± 13.0 mm. The mean reduction rates in ulcer area were 90.4% ± 0.8% at 4 wk and 99.8% ± 0.1% at 8 wk. The reduction rate was associated with the Kyoto grade of gastric atrophy at 4 wk (A0: 97.9% ± 0.6%, A1: 93.4% ± 4.1%, and A2: 89.7% ± 1.0%, respectively). In multivariate analysis, the factor predicting 90% reduction at 4 wk was gastric atrophy (Odds ratio: 5.678, 95%CI: 1.190-27.085, P = 0.029).

CONCLUSION

The healing speed of post-ESD ulcers was associated with the degree of gastric mucosal atrophy, and Helicobacter pylori eradication therapy is required to perform at younger age.

Advantages and Disadvantages of Long-term Proton Pump Inhibitor Use

Proton pump inhibitors (PPIs) potently inhibit gastric acid secretion and are widely used for treatment of acid-related diseases including gastroesophageal reflux disease and secondary prevention of aspirin/NSAID-induced ulcers. Although clinically important adverse effects of PPIs can occur, just as with other drugs, those are not frequently observed during or after administration. Thus, PPIs are regarded as relatively safe and considered to be clinically beneficial. Recently, PPIs have become frequently administered to patients with functional gastrointestinal diseases or primary prevention of drug-related gastroduodenal damage, even though their beneficial effects for those conditions have not been fully confirmed. PPIs tend to be given for conditions in which the necessity of the drug has not been clarified, thus otherwise rare adverse effects are presented as clinically relevant. Although several PPI-related adverse effects have been reported, their clinical relevance is not yet clear, since the evidence reported in those studies is not at a high enough level, as the majority are based on retrospective observational studies and the reported hazard ratios are low. It is important to administer PPIs only for patients who will gain a substantial clinical benefit and to continue to investigate their adverse effects with high quality prospective studies.

Crystal structures of the gastric proton pump

The gastric proton pump-the H⁺, K⁺-ATPase-is a P-type ATPase responsible for acidifying the gastric juice down to pH 1. This corresponds to a million-fold proton gradient across the membrane of the parietal cell, the steepest known cation gradient of any mammalian tissue. The H⁺, K⁺-ATPase is an important target for drugs that treat gastric acid-related diseases. Here we present crystal structures of the H⁺, K⁺-ATPase in complex with two blockers, vonoprazan and SCH28080, in the luminal-open state, at 2.8 Å resolution. The drugs have partially overlapping but clearly distinct binding modes in the middle of a conduit running from the gastric lumen to the cation-binding site. The crystal structures suggest that the tight configuration at the cation-binding site lowers the pK _a value of Glu820 sufficiently to enable the release of a proton even into the pH 1 environment of the stomach.