Potassium-Competitive Acid Blockers (P-CABs): Are They Finally Ready for Prime Time in Acid-Related Disease?

Potassium-competitive Acid Blockers: Current Clinical Use and Future Developments

PURPOSE OF THE REVIEW

Acid suppression with proton pump inhibitors (PPIs) represents the standard of care in the treatment of acid-related diseases. However, despite their effectiveness, PPIs display some intrinsic limitations, which underlie the unmet clinical needs that have been identified over the past decades. The aims of this review are to summarize the current status and future development of the new class of antisecretory drugs (potassium-competitive acid blockers, P-CABs) that have recently been introduced into medical practice.

RECENT FINDINGS

Over the past decades, clinical needs unmet by the current acid suppressants have been recognized, especially in the management of patients with GERD, Helicobacter pylori infection and NSAID-related peptic ulcer. The failure to address these needs is mainly due to their inability to achieve a consistent acid suppression in all patients and, particularly, to control nighttime acidity. It was then realized that an extended duration of acid suppression would exert additional benefits. The available data with P-CABs show that they are able to address these unmet clinical needs. Four different P-CABs (vonoprazan, tegoprazan, fexuprazan and keverprazan) are currently available. However, only two of them are approved outside Asia. Vonoprazan is available in North, Central and South America while tegoprazan is marketed only in Latin American countries. Two other compounds (namely linazapran glurate and zestaprazan) are presently under clinical development. While clinical trials on GERD have been performed with all P-CABs, only vonoprazan and tegoprazan have been investigated as components of Helicobacter pylori eradication regimens. The available data show that-in the above two clinical indications-P-CABs provide similar or better efficacy in comparison with PPIs. Their safety in the short-term overlaps that of PPIs, but data from long-term treatment are needed.

A Phase III Head-to-Head Study to Compare the Efficacy and Safety of Fexuprazan and Esomeprazole in Treating Patients with Erosive Esophagitis

Background: Fexuprazan (Fexuclue®; Daewoong Pharmaceutical Co., Ltd., Seoul, Korea) is a novel potassium-competitive acid blocker (P-CAB). This multi-center, randomized, double-blind, active-controlled, parallel-group, therapeutic confirmatory, phase III study was conducted to assess its efficacy and safety compared with esomeprazole (Nexium®; AstraZeneca, Gothenburg, Mölndal, Sweden) in Korean patients with erosive esophagitis (EE). Methods: This study evaluated patients diagnosed with EE at a total of 25 institutions in Korea between 13 December 2018 and 7 August 2019. After voluntarily submitting a written informed consent form, the patients were evaluated using a screening test and then randomized to either of the two treatment arms. The proportion of the patients who achieved the complete recovery of mucosal breaks at 4 and 8 weeks, the proportion of those who achieved the complete recovery of heartburn at 3 and 7 days and 8 weeks, and changes in the GERD-Health-Related Quality of Life Questionnaire (GERD-HRQL) scores at 4 and 8 weeks from baseline served as efficacy outcome measures. The incidence of treatment-emergent adverse events (TEAEs) and adverse drug reactions (ADRs) and the serum gastrin levels served as safety outcome measures. Results: The study population comprised a total of 231 patients (n = 231) with EE, including 152 men (65.80%) and 79 women (34.20%); their mean age was 54.37 ± 12.66 years old. There were no significant differences in the efficacy and safety outcome measures between the two treatment arms (p > 0.05). Conclusions: It can be concluded that the efficacy and safety of Fexuclue® are not inferior to those of esomeprazole in Korean patients with EE.

P-CAB versus PPI in the eradication of Helicobacter pylori: a systematic review and network meta-analysis

Background

The efficacy and safety of potassium-competitive acid blockers (P-CABs) in the eradication of Helicobacter pylori (Hp) remains controversial when compared with proton pump inhibitors (PPIs).

Objectives

The current study set out to compare the differences in the eradication rate and adverse reactions between eradication regimens based on P-CAB or PPI drugs and the differences between the vonoprazan-based and the tegoprazan-based regimens to explore the efficacy and safety of different Hp eradication regimens.

Data sources and methods

Databases including PubMed, EMBASE, Cochrane Library, and WOS were searched from the inception of these databases up to July 2023, and eligible randomized controlled trials (RCTs) were included. The outcome measures were the eradication rate and the incidence of adverse reactions of different regimens in treating Hp. The results were estimated as relative risk (RR) and its 95% confidence interval (CI), and R 4.2.1 software was used to perform the network meta-analysis (NMA).

Results

A total of 20 studies were included in the analysis, involving 5815 patients with Hp. In terms of eradication rate, the 2-week vonoprazan-based triple regimen (V-Tri-2w) was the best, which was superior to the 2-week PPI-based quadruple regimen [P-Qua-2w, RR = 0.9, 95% CI: (0.85-0.95)] and the 1-week tegoprazan-based triple regimen [T-Tri-1w, RR = 0.79, 95% CI: (0.64-0.97)]; the 2-week tegoprazan-based quadruple regimen (T-Qua-2w) was superior to the 1-week PPI-based triple regimen [P-Tri-1w, RR = 0.82, 95% CI: (0.67-0.99)], and there was no difference between the remaining tegoprazan-based regimens and the PPI-based or vonoprazan-based regimens. In terms of the incidence of adverse reactions, the 2-week vonoprazan-based binary regimen (V-Bi-2w) was lower than that of the 2-week PPI-based quadruple regimen [P-Qua-2w, RR = 1.98, 95% CI: (1.57-2.52)]; there was no significant difference between 1 and 2 weeks for each regimen, such as the vonoprazan-based triple regimen [RR = 1.11, 95% CI: (0.82-1.52)].

Conclusion

In the eradication treatment of Hp, the efficacy and safety of vonoprazan-based regimens are generally better than those of PPI-based regimens. Among them, the V-Tri-2w regimen has the highest eradication rate and may be the preferred choice for Hp eradication.

Good clinical practice recommendations for the diagnosis and treatment of gastroesophageal reflux disease. An expert review from the Asociación Mexicana de Gastroenterología

INTRODUCTION

Gastroesophageal reflux disease (GERD) is very prevalent in the general population, with a broad spectrum of clinical manifestations, requiring accurate diagnosis and treatment.

AIM

The aim of this expert review is to establish good clinical practice recommendations for the diagnosis and personalized treatment of GERD.

METHODS

The good clinical practice recommendations were produced by a group of experts in GERD, members of the Asociación Mexicana de Gastroenterología (AMG), after carrying out an extensive review of the published literature and discussing each recommendation at a face-to-face meeting. This document does not aim to be a clinical practice guideline with the methodology such a document requires.

RESULTS

Fifteen experts on GERD formulated 27 good clinical practice recommendations for recognizing the symptoms and complications of GERD, the rational use of diagnostic tests and medical treatment, the identification and management of refractory GERD, the overlap with functional disorders, endoscopic and surgical treatment, and GERD in the pregnant woman, older adult, and the obese patient.

CONCLUSIONS

An accurate diagnosis of GERD is currently possible, enabling the prescription of a personalized treatment in patients with this condition. The goal of the good clinical practice recommendations by the group of experts from the AMG presented in this document is to aid both the general practitioner and specialist in the process of accurate diagnosis and treatment, in the patient with GERD.

Ten-day vonoprazan-based versus fourteen-day proton pump inhibitor-based therapy for first-line Helicobacter pylori eradication in China: A meta-analysis of randomized controlled trials

Background: A shorter treatment duration potentially offers the advantage of reducing adverse events (AEs) and enhancing patient compliance for Helicobacter pylori eradication. However, the difference in eradication rates between short-duration vonoprazan-based regimens and fourteen-day proton pump inhibitor (PPI)-based therapy remained unknown. Objective: This meta-analysis aimed to compare the efficacy and safety of ten-day vonoprazan-based regimens with fourteen-day conventional PPI-based therapy for H. pylori eradication. Methods: We performed a comprehensive literature search up to November 28, 2023, using PubMed. A random-effects model was applied to conduct a meta-analysis to determine the pooled Odds Ratio (OR) with 95% confidence intervals (CIs). Results: This meta-analysis included four randomized controlled clinical trials with 1560 patients. The H. pylori eradication rate of ten-day vonoprazan-based regimens was comparable to that of fourteen-day PPI-based therapy (88.7% vs 82.9%, OR 1.53, 95% CI [0.85-2.75], p = .16) in ITT analysis. The incidence of AEs in ten-day vonoprazan-based therapy was also similar to the control group (11.2% vs 17.6%, OR 0.66, 95% CI [0.33-1.31], p = .24). Conclusion: Current evidence suggests that the ten-day vonoprazan-based regimen is as effective as fourteen-day PPI-based therapy in eradicating H. pylori, with comparable AEs. However, additional research is required for confirmation.

Efficacy comparison of 7- and 14-day P-CAB based bismuth-containing quadruple regimen with PPI based bismuth-containing quadruple regimen for Helicobacter pylori infection: rationale and design of an open-label, multicenter, randomized controlled trial

BACKGROUND

Owing to its strong acid inhibition, potassium-competitive acid blocker (P-CAB) based regimens for Helicobacter pylori (H. pylori) eradication are expected to offer clinical advantages over proton pump inhibitor (PPI) based regimens. This study aims to compare the efficacy and adverse effects of a 7-day and a 14-day P-CAB-based bismuth-containing quadruple regimen (PC-BMT) with those of a 14-day PPI-based bismuth-containing quadruple regimen (P-BMT) in patients with high clarithromycin resistance.

METHODS

This randomized multicenter controlled clinical trial will be performed at five teaching hospitals in Korea. Patients with H. pylori infection who are naive to treatment will be randomized into one of three regimens: 7-day or 14-day PC-BMT (tegoprazan 50 mg BID, bismuth subcitrate 300 mg QID, metronidazole 500 mg TID, and tetracycline 500 mg QID) or 14-day P-BMT. The eradication rate, treatment-related adverse events, and drug compliance will be evaluated and compared among the three groups. Antibiotic resistance testing by culture will be conducted during the trial, and these data will be used to interpret the results. A total of 366 patients will be randomized to receive 7-day PC-BMT (n = 122), 14-day PC-BMT (n = 122), or 14-day P-BMT (n = 122). The H. pylori eradication rates in the PC-BMT and P-BMT groups will be compared using intention-to-treat and per-protocol analyses.

DISCUSSION

This study will demonstrate that the 7-day or 14-day PC-BMT is well tolerated and achieve similar eradication rates to those of 14-day P-BMT. Additionally, the 7-day PC-BMT will show fewer treatment-related adverse effects and higher drug compliance, owing to its reduced treatment duration.

TRIAL REGISTRATION

Korean Clinical Research Information Service registry, KCT0007444. Registered on 28 June 2022, https://cris.nih.go.kr/cris/index/index.do .

Plants with potential anti-ulcerogenic activity and possible mechanism of actions based on their phyto-constitutional profile

Gastric ulcer, the most common disorder of the digestive tract is formed due to an imbalance between acid and mucus content of the stomach. However, the currently used western therapeutic regimens have many drawbacks like adverse effects, recurrence of gastric ulcers, are expensive, and also, may have interactions with other drugs. Hence, there is a need for effective alternative therapy. Medicinal herbs have been used since ancient times to treat several diseases and are also evidenced to be effective against gastric ulcers. It is also evident that medicinal herbs have been proved to be equally effective or superior as compared to the existing synthetic medicines. In this review, five herbs have been taken into consideration and assumed to be effective against gastric ulcers. Abrus mollis, Korean Thistle (Cirsium japonicum var. maackii), Astralagus complanatus Bunge, Bauhinia monandra, and Embelia ribes Burm f. are the herbs whose data is been collected and reviewed for their potential gastro-protective action. Although, their side effects and toxicity profile need to be further evaluated. Hence, the purpose of this review is to gather evidence of these five medicinal herbs and their probable mechanism of action against gastric ulcers based on their phyto-constitutional profile.

Review of the clinical development of fexuprazan for gastroesophageal reflux-related disease

Proton pump inhibitors (PPIs) are a mainstay treatment for acid peptic disorders such as gastroesophageal reflux disease (GERD). Although PPIs are considered first-line medications for acid suppression, they have notable limitations such as requiring acid-mediated activation, short half-life and duration of action, and metabolic variability. Fexuprazan is a newly developed potassium-competitive acid blocker (P-CAB), which inhibits acid generation and secretion in a competitive and reversible manner. Fexuprazan, like other P-CABs, has significantly different pharmacodynamic and pharmacokinetic properties than PPIs with potential advantages including rapid, robust, and durable acid suppression, lack of CYP2C19 metabolism, independence from food intake, and no requirement for activation into an active form. Completed clinical trials of fexuprazan have demonstrated comparable efficacy to PPIs for the healing of erosive esophagitis and relief of GERD-related esophageal symptoms without concerning safety signals. Ongoing clinical trials are evaluating fexuprazan for the prevention of NSAID-induced peptic ulcer disease, non-erosive GERD, and acute and chronic gastritis, as well as healing efficacy and maintenance of erosive esophagitis (EE). Fexuprazan is approved in South Korea for the treatment of EE and at the time of this writing is being considered for regulatory approval in several other countries. In this article, we summarize and discuss the pharmacology, efficacy, and safety of fexuprazan.

Differential effects of proton pump inhibitors and vonoprazan on vascular endothelial growth factor expression in cancer cells

Proton pump inhibitors (PPIs) are potent inhibitors of gastric acid secretion, used as first-line agents in treating peptic ulcers. However, we have previously reported that PPIs may diminish the therapeutic effect of anti-vascular endothelial growth factor (VEGF) drugs in patients with cancer. In this study, we explored the effects of vonoprazan, a novel gastric acid secretion inhibitor used for the treatment of peptic ulcers, on the secretion of VEGF in cancer cells and attempted to propose it as an alternative PPI for cancer chemotherapy. The effects of PPI and vonoprazan on VEGF expression in cancer cells were compared by real-time reverse transcription-polymerase chain reaction and ELISA. The interaction of vonoprazan and PPIs with transcriptional regulators by docking simulation analysis. In various cancer cell lines, including the human colorectal cancer cell line (LS174T), PPI increased VEGF messenger RNA expression and VEGF protein secretion, while this effect was not observed with vonoprazan. Molecular docking simulation analysis showed that vonoprazan had a lower binding affinity for estrogen receptor alpha (ER-α), one of the transcriptional regulators of VEGF, compared to PPI. Although the PPI-induced increase in VEGF expression was counteracted by pharmacological ER-α inhibition, the effect of vonoprazan on VEGF expression was unchanged. Vonoprazan does not affect VEGF expression in cancer cells, which suggests that vonoprazan might be an alternative to PPIs, with no interference with the therapeutic effects of anti-VEGF cancer chemotherapy.

GERD-related chronic cough: Possible mechanism, diagnosis and treatment

GERD, or gastroesophageal reflux disease, is a prevalent medical condition that affects millions of individuals throughout the world. Chronic cough is often caused by GERD, and chronic cough caused by GER is defined as GERD-related chronic cough (GERC). It is still unclear what the underlying molecular mechanism behind GERC is. Reflux theory, reflex theory, airway allergies, and the novel mechanism of esophageal motility disorders are all assumed to be linked to GERC. Multichannel intraluminal impedance combined with pH monitoring remains the gold standard for the diagnosis of GERC, but is not well tolerated by patients due to its invasive nature. Recent discoveries of new impedance markers and new techniques (mucosal impedance testing, salivary pepsin, real-time MRI and narrow band imaging) show promises in the diagnosis of GERD, but the role in GERC needs further investigation. Advances in pharmacological treatment include potassium-competitive acid blockers and neuromodulators (such as Baclofen and Gabapentin), prokinetics and herbal medicines, as well as non-pharmacological treatments (such as lifestyle changes and respiratory exercises). More options have been provided for the treatment of GERC other than acid suppression therapy and anti-reflux surgery. In this review, we attempt to review recent advances in GERC mechanism, diagnosis, and subsequent treatment options, so as to provide guidance for management of GERC.

A population PK–PD model of YH4808 , a novel P‐CAB , and intragastric pH that incorporated negative feedback by increased intragastric pH onto the systemic exposure to YH4808

YH4808 is a novel potassium‐competitive acid blocker that is under clinical development to treat patients with gastroesophageal reflux disease and peptic ulcer diseases. In this study, the pharmacokinetic (PK) and pharmacodynamic (PD) profiles of YH4808 were modeled in healthy male volunteers who received a single oral dose of YH4808 at 30, 50, 100, 200, 400, 600, and 800 mg or matching placebo and multiple once‐daily oral doses of YH4808 at 100, 200, and 400 mg or matching placebo for 7 days. A population PK–PD model adequately described the time–concentration‐effect profiles of YH4808. The maximum increasing effect of YH4808 on intragastric pH was 4.38, which was higher than the observed maximum increase in intragastric pH after omeprazole at 40 mg (2.2 in pH). The maximum inhibitory effect by the increased intragastric pH on the exposure to repeated YH4808 was 58% from baseline. Monte–Carlo simulation experiments based on the final model showed that YH4808 at 200 mg will produce a higher percentage of time at pH > 4 over 24 h on day 1 than observed value of esomeprazole at 40 mg once‐daily, an active comparator (84.7% time vs. 58.3% time, respectively). Because YH4808 at ≥200 mg resulted in a higher percentage of time at intragastric pH > 4 than seen after once‐daily esomeprazole at 40 mg and YH4808 showed acceptable tolerability at a single‐dose of 30–800 mg, we suggest to test the 200 mg once daily dosage regimen in further clinical trials of YH4808.

Management of Helicobacter pylori infection: the Maastricht VI/Florence consensus report

Helicobacter pyloriInfection is formally recognised as an infectious disease, an entity that is now included in the International Classification of Diseases 11th Revision. This in principle leads to the recommendation that all infected patients should receive treatment. In the context of the wide clinical spectrum associated with Helicobacter pylori gastritis, specific issues persist and require regular updates for optimised management.The identification of distinct clinical scenarios, proper testing and adoption of effective strategies for prevention of gastric cancer and other complications are addressed. H. pylori treatment is challenged by the continuously rising antibiotic resistance and demands for susceptibility testing with consideration of novel molecular technologies and careful selection of first line and rescue therapies. The role of H. pylori and antibiotic therapies and their impact on the gut microbiota are also considered.Progress made in the management of H. pylori infection is covered in the present sixth edition of the Maastricht/Florence 2021 Consensus Report, key aspects related to the clinical role of H. pylori infection were re-evaluated and updated. Forty-one experts from 29 countries representing a global community, examined the new data related to H. pylori infection in five working groups: (1) indications/associations, (2) diagnosis, (3) treatment, (4) prevention/gastric cancer and (5) H. pylori and the gut microbiota. The results of the individual working groups were presented for a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in various clinical fields.

Clinical trial: seven-day vonoprazan- versus 14-day proton pump inhibitor-based triple therapy for first-line Helicobacter pylori eradication

BACKGROUND

One-week triple therapy with vonoprazan is endorsed by Japanese guidelines as an alternative to proton pump inhibitor (PPI)-based triple therapy for first-line Helicobacter pylori eradication. This contrasts with Western guidelines recommending 2-week PPI-based triple therapy.

AIM

To verify the non-inferiority of 1-week vonoprazan-based triple therapy versus 2-week PPI-based triple therapy as first-line H. pylori eradication in a multiracial Asian cohort.

METHODS

Randomised controlled trial of treatment-naïve patients with H. pylori infection assigned 1:1 to either 7 days amoxicillin 1 g + clarithromycin 500 mg + vonoprazan 20 mg twice per day or 14 days amoxicillin 1 g + clarithromycin 500 mg + omeprazole OR esomeprazole OR rabeprazole 20 mg twice/day. Subjects were randomly assigned to each PPI 1:1:1 Demographics, H. pylori resistance, CYP 2C19 genotype, eradication success and safety profiles were compared between groups.

RESULTS

Between June 2019 and June 2021, 252 of 1097 subjects screened were randomised. 244 (age [SD] 51.7 [14.6]) received vonoprazan- (n = 119) or PPI-based (n = 125) triple therapy. Eradication rates by intention-to-treat analysis were 87.4% (vonoprazan-based triple therapy) versus 88.0% (PPI-based triple therapy. By per protocol analysis: 96.3% (vonoprazan-based triple therapy) versus 94.0% (PPI-based triple therapy). Clarithromycin resistance predicted treatment failure on multivariate analysis: RR 11.4; 95% CI [1.4-96.3], p = 0.025. No significant differences in CYP 2C19 genotypes or adverse events occurred between groups.

CONCLUSION

One-week vonoprazan-based triple therapy achieved comparable efficacy to 2-week PPI-based triple therapy and was well tolerated.

The Association of Long-Term Use of Proton Pump Inhibitors and Histamine H2 Receptor Antagonists with Clinical Complications in Patients with Severe Sepsis

Objective. Proton pump inhibitors (PPIs) are commonly used to treat gastric acidity, and their frequent use may trigger various malfunctioning, such as cardiac, renal, and liver function failure. In the current study, we evaluated the association between the excessive use of the PPIs and the clinical complications of intensive care unit (ICU) septic patients. Methods. A total of 208188 patients were analyzed from 2016 to 2017 through the China Critical Care Sepsis Trial (CCCST) database. The characteristics of the study group and outcome of events from the PPI- and H2 blocker-using groups were reported. To get unbiased results, the data from the target trials were randomly assigned for PPI and H2 blocker groups. Result. The data revealed 43.34 excess deaths (95% confidence intensive (CI) 25.12 to 62.02) per 1000 patients in patients extensively consuming PPI drugs. The sepsis with chronic kidney disease attributed to deaths 21.36; 95% CI (9.34 to 23.23). However, comorbidities, including circulatory diseases (16.34; 95% CI 5.78 to 23.45), nervous system (2.08; 95% CI 1.56 to 6.34), mental disorders (1.87; 95% CI 1.65 to 2.95), genitourinary system (5.23; 95% CI 3.69 to 8.89), and infectious and parasitic disease (4.17; 95% CI 1.44 to 7.49), were also reported. Extensive use of the PPIs and H2 blockers was associated with esophageal adenocarcinoma, Barrett’s esophagus, neoplasms, and GI cancers. Conclusion. We conclude that the excessive use of PPI in sepsis patients triggers chronic kidney disease which has a higher clinical complication rate among others.

The views of African and Middle Eastern Gastroenterologists on the management of mild-to-moderate, non-erosive gastro-esophageal reflux disease (GERD)

INTRODUCTION

Gastro-esophageal reflux disease (GERD) is a common gastrointestinal disorder that occurs when backflow of the gastric contents into the esophagus results in troublesome symptoms. Though GERD has been extensively studied in Western populations, literature on the management of GERD in patients in Africa and Middle East (AME) is scarce.

AREAS COVERED

In this review, we provide an overview of the management of mild-to-moderate GERD in AME. Here we focus on the efficacy and safety of currently available treatments for GERD to help physicians and community pharmacists appropriately manage patients with mild-to-moderate GERD in the primary healthcare setting, detailing specific situations and patient scenarios that are relevant to the region, including management of GERD during Ramadan and post-bariatric surgery.

EXPERT OPINION

Under-appreciation of the burden of GERD in the region has resulted in a lack of consensus on management. Barriers that currently prevent the adoption of treatment guidelines in the primary healthcare setting may include lack of availability of local guidelines and referral systems, a paucity of region-specific research, and dogmatic adherence to traditional practice. By increasing awareness, strengthening knowledge, and by more effective utilization of resources, physicians and pharmacists could optimize GERD management strategies to better support patients.

Vonoprazan in the management of gastric/peptic ulcers: a systematic review of safety data

Introduction

Although potassium-competitive acid blockers (P-CABs) prompted safety concerns when first developed, they ultimately proved to have a favourable safety profile.

Aim

To assess the safety of vonoprazan in the management of gastroesophageal reflux disease (GERD), peptic ulcers, or gastroduodenal mucosal lesions induced by chronic use of aspirin or non-steroidal anti-inflammatory drugs (NSAIDs).

Material and methods

From March to June 2021, a literature search was conducted using Medline via PubMed, Cochrane library, Lilacs, SciELO, and Centre for Reviews and Dissemination (CRD) electronic databases. After applying the eligibility criteria, 10 studies were included in this review. Of these 10 articles, vonoprazan was used as initial therapy in 6 and as maintenance therapy in 4. Adverse event rates were similar for vonoprazan and proton-pump inhibitors (PPIs).

Conclusions

Our findings suggest that vonoprazan is a safe option for the management of erosive oesophagitis, gastric/peptic ulcers, or peptic ulcers induced by chronic use of aspirin or NSAIDs.

Vonoprazan for treatment of gastroesophageal reflux disease: Research advances

Gastroesophageal reflux disease is a common gastrointestinal disease that can be effectively treated by drugs alone. Proton pump inhibitors are the currently mainstay drugs for the treatment of gastroesophageal reflux disease, but are insufficiently effective. Vonoprazan, which is a new type of drug that inhibits gastric acid secretion, has been employed for the management of gastroesophageal reflux disease. In this article, we comprehensively review the current evidence regarding clinical efficacy and safety of vonoprazan for the treatment of gastroesophageal reflux disease to guide the clinical decision.

Revisiting Therapeutic Strategies for H. pylori Treatment in the Context of Antibiotic Resistance: Focus on Alternative and Complementary Therapies

The prevalence of Helicobacter pylori infection remains significant worldwide and it depends on many factors: gender, age, socio-economic status, geographic area, diet, and lifestyle. All successful infectious diseases treatments use antibiotic-susceptibility testing, but this strategy is not currently practical for H. pylori and the usual cure rates of H. pylori are lower than other bacterial infections. Actually, there is no treatment that ensures complete eradication of this pathogen. In the context of an alarming increase in resistance to antibiotics (especially to clarithromycin and metronidazole), alternative and complementary options and strategies are taken into consideration. As the success of antibacterial therapy depends not only on the susceptibility to given drugs, but also on the specific doses, formulations, use of adjuvants, treatment duration, and reinfection rates, this review discusses the current therapies for H. pylori treatment along with their advantages and limitations. As an alternative option, this work offers an extensively referenced approach on natural medicines against H. pylori, including the significance of nanotechnology in developing new strategies for treatment of H. pylori infection.

Vonoprazan-based triple therapy is effective for Helicobacter pylori eradication irrespective of clarithromycin susceptibility

BACKGROUND

Helicobacter pylori causes peptic ulcers and accounts for over 90% of gastric cancers; however, eradication rates have been declining due to antimicrobial resistance. Vonoprazan (VPZ), a potassium-competitive acid blocker, produces rapid and profound gastric acid suppression and has shown promising effects in the improvement of H. pylori eradication rates. The efficacy and safety of VPZ-based triple therapy as a first-line regimen for H. pylori eradication and its relationship with clarithromycin (CAM) susceptibility were evaluated.

METHODS

From May 2015 to September 2017, H. pylori-infected patients who underwent esophagogastroduodenoscopy with CAM susceptibility testing were prospectively enrolled. Patients received a 7-day triple therapy regimen (VAC) of VPZ (20 mg), amoxicillin (750 mg), and CAM (200 mg) twice daily. Eradication rates, demographics, CAM susceptibility, and safety profiles were assessed.

RESULTS

VAC was administered to 146 patients (median age: 63, range: 22-85 years) (60% of whom were females) who underwent CAM susceptibility testing, and 131 patients underwent ¹³C-urea breath testing to evaluate eradication success. The prevalence of CAM resistance was 34.2%. The overall eradication rates of VAC in per protocol (PP) and "intention to treat" (ITT) analyses were 90.8% (n = 131) and 81.5% (n = 146), respectively. In PP analysis for CAM susceptibility, the eradication rates of VAC were comparable between CAM-sensitive (91.6%, n = 83) and CAM-resistant (89.4%, n = 47) strains. The corresponding rates from the ITT analysis were 80.0% (n = 95) and 84.0% (n = 50), respectively. No adverse events requiring discontinuation of VAC were observed.

CONCLUSIONS

CAM-resistant H. pylori was prevalent in one-third of patients in the Tokyo metropolitan area. VPZ-based triple therapy was highly effective and well-tolerated irrespective of CAM susceptibility. Therefore, it could be a valuable first-line treatment regimen for H. pylori infection.

Pharmacologic treatment of GERD: Where we are now, and where are we going?

The introduction of acid inhibition in clinical practice has revolutionized the management of acid-related diseases, leading to the virtual abolition of elective surgery for ulcer disease and relegating antireflux surgery to patients with gastroesophageal reflux disease (GERD) not adequately managed by medical therapy. Proton pump inhibitors (PPIs) are the antisecretory drugs of choice for the treatment of reflux disease. However, these drugs still leave some unmet clinical needs in GERD. PPI-refractoriness is common, and persistent symptoms are observed in up to 40-55% of daily PPI users. Potassium-competitive acid blockers (P-CABs) clearly overcome many of the drawbacks and limitations of PPIs, achieving rapid, potent, and prolonged acid suppression, offering the opportunity to address many of the unmet needs. In recent years, it has been increasingly recognized that impaired mucosal integrity is involved in the pathogenesis of GERD. As a consequence, esophageal mucosal protection has emerged as a new, promising therapeutic avenue. When P-CABS are used as add-on medications to standard treatment, a growing body of evidence suggests a significant additional benefit, especially in the relief of symptoms not responding to PPI therapy. On the contrary, reflux inhibitors are considered a promise unfulfilled, and prokinetic agents should only be used on a case-by-case basis.

Evaluation and Treatment of Patients with Persistent Reflux Symptoms Despite Proton Pump Inhibitor Treatment

Despite the exceptional efficacy of proton pump inhibitors (PPIs) in healing reflux esophagitis complicating gastroesophageal reflux disease (GERD), up to 40% of patients who take PPIs for GERD complain of persistent GERD symptoms. There is no clear consensus on the type, dosing, and duration of PPI therapy required to establish a diagnosis of PPI-refractory GERD symptoms, but most authorities do not consider patients "PPI-refractory" unless they have been on double-dose PPIs. This article discusses the mechanisms that might underlie heartburn that does not respond PPIs and an approach to the management of patients with PPI-refractory GERD symptoms.

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.

Gastrointestinal pharmacology: practical tips for the esophagologist

Gastroesophageal reflux disease (GERD) is primarily a motor disorder, and its pathogenesis is multifactorial. As a consequence, treatment should be able to address the underlying pathophysiology. Proton pump inhibitors (PPIs) are the mainstay of medical therapy for GERD, but these drugs only provide the control of symptoms and lesions without curing the disease. However, continuous acid suppression with PPIs is recommended for patients with Barrett's esophagus because of their potential chemopreventive effects. In addition to the antisecretory activity, these compounds display several pharmacological properties, often overlooked in clinical practice. PPIs can indeed affect gastric motility, exert a mucosal protective effect, and an antioxidant, anti-inflammatory, and antineoplastic activity, also protecting cancer cells from developing chemo- or radiotherapeutic resistance. Even in the third millennium, current pharmacologic approaches to address GERD are limited. Reflux inhibitors represent a promise unfulfilled, effective and safe prokinetics are lacking, and antidepressants, despite being effective in selected patients, give rise to adverse events in a large proportion of them. While waiting for new drug classes (like potassium-competitive acid blockers), reassessing old drugs (namely alginate-containing formulations), and paving the new avenue of esophageal mucosal protection are, at the present time, the only reliable alternatives to acid suppression.

Refractory Gastroesophageal Reflux Disease and Functional Heartburn

This report discusses the potential mechanisms that might underlie refractory GERD and functional heartburn, and how to distinguish among those mechanisms using a systematic evaluation that includes careful medical history, endoscopy with esophageal biopsy, esophageal manometry, and esophageal multichannel intraluminal impedance-pH monitoring. The report provides an approach to patient management that depends on the underlying mechanism identified by this systematic evaluation.

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.

Comparison of pharmacokinetic characteristics of two Tegoprazan (CJ-12420) formulations in healthy male subjects

Proton-pump inhibitors (PPIs) are effectively used to treat acid-related diseases, including gastroesophageal reflux disease (GERD); however, many unmet medical needs still exist. As a new treatment option, potassium-competitive acid blockers (P-CABs), such as tegoprazan, have been developed. This study was performed to compare the pharmacokinetics (PKs) between two formulations (test and reference drugs) of tegoprazan 100 mg tablets. A randomized, single oral dose, two-treatment, two-period, two-sequence study was conducted with 12 healthy subjects. Each subject received the test drug or reference drug in the first period and the alternative treatment in the second period. For PK evaluation, blood samples were collected up to 48 hours post-dose in each period. The plasma concentrations of tegoprazan and its active metabolite (M1) were measured by liquid chromatography-tandem mass spectrometry. PK parameters, including maximum plasma concentration (Cmax) and area under the concentration-time curve from zero to the last measurable time (AUClast), were estimated using a non-compartmental method. The plasma concentration-time profiles of the two formulations were comparable. The geometric mean ratios [90% confidence intervals (CIs)] of the test drug to the reference drug for Cmax and AUClast were 0.98 (0.85-1.12) and 1.03 (0.93-1.13), respectively. The corresponding values of M1 were 0.99 (0.89-1.11) and 1.01 (0.93-1.09), respectively. The two formulations of tegoprazan exhibited comparable PK profiles, fulfilling the regulatory criteria for bioequivalence.

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.

Vonoprazan versus proton pump inhibitors for the management of gastroesophageal reflux disease: A protocol for a systematic review with meta-analysis

BACKGROUND AND AIM

Vonoprazan, a novel potassium-competitive acid blocking agent, is used in the management of gastroesophageal reflux disease (GERD). We aim to perform a systematic review and meta-analysis for the comparison of the effects of vonoprazan and proton pump inhibitors (PPIs) in GERD in randomized controlled trials (RCTs).

METHODS

A systematic and comprehensive search will be performed using MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), Google Scholar, and clinical trial registries, for studies published up to September 2018. Only randomized clinical trials will be included. Primary outcomes of symptoms and esophageal erosion improvement in the intention-to-treat analysis, and secondary outcomes of symptoms and esophageal erosion improvement rate in the per protocol analysis, the comparative efficacy in terms of healing rate of esophageal erosion on endoscopy, the comparative efficacy in terms of improvement of esophageal impedance-pH study, adverse events, long-term safety, and the comparative efficacy in terms of CYP2C19 metabolite levels will be studied. The quality of included studies will be assessed using the modified risk of bias tool. Heterogeneity of estimates across studies as well as publication bias will be assessed. This systematic review and meta-analysis will be performed according to the protocol recommended by the Cochrane Collaboration and reported according to the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines. All statistical analyses will be conducted using Stata SE version 15.0.

RESULTS

The results of this systematic review and meta-analysis will be published in a peer-reviewed journal.

CONCLUSION

To our knowledge, this systematic review and meta-analysis will be the first to evaluate existing research comparing Vonoprazan and PPIs in GERD. Our study will provide information about the effect of vonoprazan and PPIs in GERD in RCTs. The review will benefit patients, healthcare providers, and policymakers.

Long-term outcomes of patients with symptomatic gastroesophageal reflux disease treated with vonoprazan

OBJECTIVE

The novel potassium-competitive acid blocker, vonoprazan, provides rapid and effective acid suppression. The aim of this study is to evaluate the long-term outcomes of patients with symptomatic gastroesophageal reflux disease (GERD) treated with vonoprazan.

METHODS

This retrospective cohort study included 55 patients with symptomatic GERD treated with vonoprazan who have been followed for more than one year. The effectiveness of vonoprazan on gastrointestinal symptoms was evaluated using the Izumo scale, a self-reported questionnaire reflecting quality of life related to various abdominal symptoms.

RESULTS

These 55 patients with symptomatic GERD had non-erosive reflux disease (n = 30) or erosive esophagitis (n = 25). Vonoprazan (10 mg) for one month improved GERD symptoms in 89% (responders) and the improvement was maintained at one year in 82% without additional treatment. One-year maintenance therapy resulted in sustained resolution of GERD symptoms in 47%. Of the 49 responders, nine patients had relapse of GERD symptoms and dose escalation of vonoprazan improved the symptoms in six patients. Postprandial distress and the presence of erosive esophagitis before starting vonoprazan were identified as significant negative and positive predictors of sustained resolution of GERD symptoms for one year, respectively. Epigastric pain, postprandial distress, constipation and diarrhea were significantly improved at one-month and maintained at one year. After one-year of treatment, the endoscopic healing rate of erosive esophagitis was 95%.

CONCLUSION

One-year treatment with vonoprazan significantly improves GERD symptoms and endoscopic healing of erosive esophagitis is satisfactory. The long-term use of vonoprazan is effective and useful to control GERD.

Recent advances in Barrett's esophagus

Barrett's esophagus (BE) is the only known precursor of esophageal adenocarcinoma, one of the few cancers with increasing incidence in developed countries. The pathogenesis of BE is unclear with regard to either the cellular origin of this metaplastic epithelium or the manner in which malignant transformation occurs, although recent data indicate a possible junctional origin of stem cells for BE. Treatment of BE may be achieved using endoscopic eradication therapy; however, there is a lack of discriminatory tools to identify individuals at sufficient risk for cancer development in whom intervention is warranted. Reduction in gastroesophageal reflux of gastric contents including acid is mandatory to achieve remission from BE after endoscopic ablation, and can be achieved using medical or nonmedical interventions. Research topics of greatest interest include the mechanism of BE development and transformation to cancer, risk stratification methods to identify individuals who may benefit from ablation of BE, optimization of eradication therapy, and surveillance methods to ensure that remission is maintained after eradication is achieved.

Effect of food on the pharmacokinetics of YH4808, a potassium-competitive acid blocker, after single- and multiple-oral dosing in healthy subjects

PURPOSE

YH4808 is a potassium-competitive acid blocker, developed for the treatment of acid-related disorders. Two clinical studies in healthy male subjects were conducted to evaluate the effect of food on the pharmacokinetics of YH4808.

METHODS

The first study, a randomized, three-treatment, three-period, crossover study, compared pharmacokinetics of YH4808 (300 mg) after a single dose at fed state with a standard or a high-fat meal to those at fasted state. The second study, a randomized, two-treatment, two-period, crossover study, investigated pharmacokinetics at fasted or fed state with a standard meal after twice daily dose of YH4808 (100 mg) for 7 days. Bloods for pharmacokinetic evaluation were sampled up to 48 h post-dose and 24 h post-dose at steady state, respectively. The pharmacokinetic parameters were estimated by non-compartmental method.

RESULTS

After single dosing, the geometric means of maximum plasma concentration increased by 1.2 and 2.1 times in the fed states with a standard meal and a high-fat meal, respectively, of that in fasted state. Corresponding values of area under the plasma concentration-time curve (AUC) from time 0 to the last measurable time point increased by 1.8 and 2.8 times, respectively. After multiple dosing, the geometric mean for 24-h AUC at steady state slightly increased in fed state by 1.1 times of that in fasted state.

CONCLUSIONS

As fat content of the food increased, the systemic exposure of YH4808 after single dosing increased. However, systemic exposures at steady state after multiple dosing between fasted and fed states were similar.

TRIAL REGISTRATION

ClinicalTrials.gov registry no.: NCT01520012.

Non-variceal upper gastrointestinal bleeding

Non-variceal upper gastrointestinal bleeding (NVUGIB) is bleeding that develops in the oesophagus, stomach or proximal duodenum. Peptic ulcers, caused by Helicobacter pylori infection or use of NSAIDs and low-dose aspirin (LDA), are the most common cause. Although the incidence and mortality associated with NVUGIB have been decreasing owing to considerable advances in the prevention and management of NVUGIB over the past 20 years, it remains a common clinical problem with an annual incidence of ∼67 per 100,000 individuals in the United States in 2012. NVUGIB is a medical emergency, and mortality is in the range ∼1-5%. After resuscitation and initial assessment, early (within 24 hours) diagnostic and therapeutic endoscopy together with intragastric pH control with proton pump inhibitors (PPIs) form the basis of treatment. With a growing ageing population treated with antiplatelet and/or anticoagulant medications, the clinical management of NVUGIB is complex as the risk between gastrointestinal bleeding events and adverse cardiovascular events needs to be balanced. The best clinical approach includes identification of risk factors and prevention of bleeding; available strategies include continuous treatment with PPIs or H. pylori eradication in those at increased risk of developing NVUGIB. Treatment with PPIs and/or use of cyclooxygenase-2-selective NSAIDs should be implemented in those patients at risk of NVUGIB who need NSAIDs and/or LDA.

Vonoprazan treatment improves gastrointestinal symptoms in patients with gastroesophageal reflux disease

The effects of vonoprazan, a new potassium-competitive acid blocker, on gastroesophageal reflux disease (GERD) symptom are not fully elucidated. The aim of this study is to determine the effect of vonoprazan on GERD and associated gastrointestinal symptoms. We retrospectively reviewed 88 Helicobacter pylori negative patients with GERD treated with vonoprazan 10 mg daily. Symptoms were evaluated using the Izumo scale, which reflects quality of life related to various abdominal symptoms. The rates of improvement and resolution of GERD symptoms were 86% (76/88) and 57% (50/88), respectively. Improvement and resolution in patients with erosive esophagitis was higher than in those with non-erosive reflux disease (91% vs 83%, p = 0.260 and 71% vs 47%, p = 0.025, respectively). We attempted to identify factors which predict the effects of vonoprazan. Multivariate analysis identified advanced age (≥60-year-old) (odds ratio [OR] 7.281, 95% confidence interval [CI] 2.056-25.776, p = 0.002), obesity (BMI ≥ 24) (OR 3.342, 95%CI 1.124-9.940, p = 0.030) and erosive esophagitis (OR 4.368, 95%CI 1.281-14.895, p = 0.018) as positive predictors of resolution of GERD symptoms. Alcohol use (OR 0.131, 95%CI 0.027-0.632, p = 0.011) and history of H. pylori eradication (OR 0.171, 95%CI 0.041-0.718, p = 0.015) were identified as negative predictors. Vonoprazan also improved epigastric pain (73%), postprandial distress (60%), constipation (58%) and diarrhea (52%) in patients with GERD. In conclusion, vonoprazan 10 mg daily is effective in improving GERD symptoms. Advanced age, obesity, erosive esophagitis, alcohol use and history of H. pylori eradication influence the resolution of GERD symptoms. Treatment with vonoprazan favorably affects gastrointestinal symptoms in patients with GERD.

Helicobacter pylori-Induced Changes in Gastric Acid Secretion and Upper Gastrointestinal Disease

Appropriate management of Helicobacter pylori infection of the human stomach is evolving and remains a significant clinical challenge. Acute infection results in hypochlorhydria, whereas chronic infection results in either hypo- or hyperchlorhydria, depending upon the anatomic site of infection. Acute hypochlorhydria facilitates survival of the bacterium and its infection of the stomach. Interestingly, most patients chronically infected with H. pylori manifest a pangastritis with reduced acid secretion due to bacterial virulence factors, inflammatory cytokines, and various degrees of gastric atrophy. While these patients are predisposed to develop gastric adenocarcinoma (~1%), there is increasing evidence from population studies that they are also protected from gastroesophageal reflux disease (GERD), Barrett's esophagus (BE), and esophageal adenocarcinoma (EAC). Eradication of H. pylori, in these patients, may provoke GERD in predisposed individuals and may be a contributory factor for the rising incidence of refractory GERD, BE, and EAC observed in Westernized societies. Only ~10% of chronically infected patients, mainly the young, manifest an antral predominant gastritis with increased acid secretion due to a decrease in somatostatin and increase in gastrin secretion; these patients are predisposed to develop peptic ulcer disease. H. pylori-induced changes in acid secretion, in particular hypochlorhydria, may allow ingested microorganisms to survive transit through the stomach and colonize the distal intestine and colon. Such perturbation of gut microbiota, i.e. dysbiosis, may influence human health and disease.

Study on pharmacokinetics and bioequivalence of Vonoprazan pyroglutamate in rats by liquid chromatography with tandem mass spectrometry

Vonoprazan Fumarate (TAK-438F) is a new and effective drug approved in Japan in 2014 for treatment and prevention of acid-related diseases (ARDs), which exhibits many advantages compared with traditional proton-pump inhibitors (PPIs). However, the clinical applications of TAK0-438F suffers limitation due to the lack of injection dosage form. Efforts to overcome this limitation lead to the systhesis of Vonoprazan pyroglutamate (TAK-438P) for its high water solubility and more potent antisecretory effect. This was the first report to establish and validate a reliable and sensitive LC-MS/MS method for the quantification of TAK-438P in rat plasma and tissues (heart, liver, spleen, liver, kidney, rain, stomach and small intestine). All the features of the developed method suggested it was within bioanalytical criteria recommended by regulatory authorities. Furthermore, the developed method was applied to the exploration of the bioequivalence between TAK-438P and TAK-438F, as well as the pharmacokinetics and tissue distribution of TAK-438P. The results showed that there was no significant differences between TAK-438P and TAK-438F after oral administration of the same dose. Besides, TAK-438P was rapidly absorbed and eliminated in rat plasma. And it was widely distributed and there was no long-term accumulation in most tissues. Notably, more than 2000ng/mL was observed in stomach 12h after oral administration. The high accumulation revealed that stomach was likely to be the target organs of TAK-438P.

Effect of Vonoprazan, a Potassium-Competitive Acid Blocker, on the 13C-Urea Breath Test in Helicobacter pylori-Positive Patients

BACKGROUND AND AIM

Vonoprazan (VPZ) is a new oral potassium-competitive acid blocker that has recently become available. The aim of this study was to investigate the effects of VPZ on the urease activity of H. pylori as measured by the ¹³C-urea breath test (¹³C-UBT).

PATIENTS AND METHODS

A total of 60 patients (26 men, 34 women; mean age 53.2 ± 13.6 years) who were diagnosed as H. pylori-positive were recruited. The patients were randomly allocated to three treatment groups: lansoprazole (LPZ) 30 mg (n = 20), VPZ 20 mg (n = 20) once daily for 3 weeks, or the control group (n = 20). The ¹³C-UBT was carried out at baseline and after 3 weeks of treatment, and the baseline and after treatment results then compared. Δ¹³C‰ ≥ 2.5‰ was considered H. pylori-positive.

RESULTS

Four patients failed to complete the medication and were omitted from the analysis; data from the LPZ group (n = 18), VPZ group (n = 18), and control group (n = 20) were analyzed. The control group showed no significant change in ¹³C-UBT data between baseline and the completion of 3-week treatment (baseline: 26.6 ± 23.0‰, completion: 21.1 ± 13.1‰). The ¹³C-UBT data at week 3 were significantly decreased in both the VPZ group (baseline: 32.8 ± 22.7‰, completion: 7.6 ± 9.2‰, p = 0.0002) and the LPZ group (baseline: 41.8 ± 33.4‰; completion: 9.6 ± 8.8‰, p = 0.0006) compared to baseline.

CONCLUSIONS

VPZ treatment reduced the value of UBT, warning that UBT for patients with VPZ treatment should be evaluated carefully.

A Comparative Study of a New Class of Gastric Acid Suppressant Agent Named Vonoparazan versus Esomeprazole for the Eradication of Helicobacter pylori

BACKGROUND

Helicobacter pylori eradication rates have decreased worldwide. Gastric acid inhibition during treatment is important to eradicate these bacteria successfully. A new potassium-competitive acid blocker, vonoprazan (VPZ), has been shown to achieve high eradication rates in a previous randomized controlled trial.

OBJECTIVE

To determine the efficacy of VPZ for H. pylori eradication.

METHODS

A total of 874 patients were enrolled; 431 received esomeprazole (EPZ) and 443 received VPZ. First-line regimens contained clarithromycin (CAM) 200 mg b.i.d., amoxicillin 750 mg b.i.d., and either EPZ 20 mg b.i.d. or VPZ 20 mg b.i.d. for 7 days. Metronidazole 250 mg b.i.d. replaced CAM in the second-line regimens. The eradication of H. pylori was assessed by 13C-urea breath tests 4-8 weeks after each therapy.

RESULTS

The overall first-line eradication rate was 79.9% (341/427) with EPZ vs. 86.3% (377/439) with VPZ (p = 0.019). The second-line eradication rate was 83.3% (45/51) with EPZ vs. 91.1% (41/45) with VPZ (p = 0.900).

CONCLUSION

VPZ was significantly more effective than EPZ for first-line treatment. However, for second-line treatment, there was no significant difference between EPZ and VPZ.

Vonoprazan-based therapy for Helicobacter pylori eradication: experience and clinical evidence

Stable suppression of gastric acid secretion is a crucial factor in Helicobacter pylori eradication. Vonoprazan is a potassium-competitive acid blocker recently approved for use in Japan. As vonoprazan has a long duration of action and causes rapid and strong inhibition of gastric acid secretion, it has gained clinical attention for treating erosive oesophagitis, peptic ulcers, and H. pylori infection. In this review, we discuss the recent knowledge regarding the safety and efficacy of vonoprazan, focusing on its use in H. pylori eradication. The latest literature and our clinical experience have shown that vonoprazan-based therapies have satisfactory eradication rates. Additionally, vonoprazan-based therapies are associated with similar rates of adverse events as standard triple therapies with conventional proton-pump inhibitors.

Pharmacokinetics and Safety of Triple Therapy with Vonoprazan, Amoxicillin, and Clarithromycin or Metronidazole: A Phase 1, Open-Label, Randomized, Crossover Study

INTRODUCTION

Vonoprazan (TAK-438) is a novel potassium-competitive acid blocker that inhibits gastric H(+), K(+)-ATPase. The objectives of this study were to evaluate the influence of triple therapy with vonoprazan-amoxicillin-clarithromycin or vonoprazan-amoxicillin-metronidazole on the pharmacokinetics of each component of the triple therapies (primary) and to evaluate the safety and tolerability of vonoprazan-based triple therapies (secondary) in healthy adults.

METHODS

In this single-center, phase 1, open-label, randomized, four-way crossover study, Helicobacter pylori-negative, healthy Japanese male subjects were randomly assigned to 1 of 4 treatment sequences in two cohorts (12 subjects per cohort). Each treatment sequence comprised four treatment periods separated by a washout period of 7 or 14 days. Pharmacokinetic parameters for vonoprazan, amoxicillin, clarithromycin and metronidazole in single therapy or triple therapies were assessed. All adverse events were recorded.

RESULTS

Compared with single therapy, triple therapy with vonoprazan-amoxicillin-clarithromycin increased the area under the plasma concentration-time curve from time 0-12 h (AUC0-12) and maximum plasma concentration (C max) of plasma vonoprazan free base by 1.846- and 1.868-fold, respectively, and increased the AUC0-12 and C max of plasma clarithromycin by 1.450- and 1.635-fold, respectively. Triple therapy with vonoprazan-amoxicillin-metronidazole had no influence on the pharmacokinetics of vonoprazan or metronidazole. The pharmacokinetics of amoxicillin was not influenced by vonoprazan-based triple therapies. Seven adverse events were reported. Two subjects discontinued because of an adverse event (rash, liver function test abnormal); both events were considered to be study drug-related.

CONCLUSION

In healthy Japanese male subjects, triple therapy with vonoprazan-amoxicillin-clarithromycin increased vonoprazan and clarithromycin exposure. The safety and tolerability profile of triple therapy with vonoprazan-amoxicillin-clarithromycin or vonoprazan-amoxicillin-metronidazole was favorable in this population.

FUNDING

Takeda Pharmaceutical Company Ltd.

TRIAL REGISTRATION

JapicCTI-153102.

Potassium-competitive acid blockers: Advanced therapeutic option for acid-related diseases

Acid-related diseases (ARDs), such as peptic ulcers and gastroesophageal reflux disease, represent a major health-care concern. Some major milestones in our understanding of gastric acid secretion and ARD treatment reached during the last 50years include 1) discovery of histamine H₂-receptors and development of H₂-receptor antagonists, 2) identification of H⁺,K⁺-ATPase as the parietal cell proton pump and development of proton pump inhibitors (PPIs), and 3) identification of Helicobacter pylori (H. pylori) as the major cause of peptic ulcers and development of effective eradication regimens. Although PPI treatments have been effective and successful, there are limitations to their efficacy and usage, i.e. short half-life, insufficient acid suppression, slow onset of action, and large variation in efficacy among patients due to CYP2C19 metabolism. Potassium-competitive acid blockers (P-CABs) inhibit H⁺,K⁺-ATPase in a reversible and K⁺-competitive manner, and exhibit almost complete inhibition of gastric acid secretion from the first dose. Many pharmaceutical companies have tried to develop P-CABs, but most of their clinical development has been discontinued due to safety concerns or a similar efficacy to PPIs. Revaprazan was developed in Korea and was the first P-CAB approved for sale. Vonoprazan, approved in 2014 in Japan, has a completely different chemical structure and higher pKa value compared to other P-CABs, and exhibits rapid onset of action and prolonged control of intragastric acidity. Vonoprazan is an effective treatment for ARDs that is especially effective in healing reflux esophagitis and for H. pylori eradication. P-CABs, such as vonoprazan, promise to further improve the management of ARDs.

The Toronto Consensus for the Treatment of Helicobacter pylori Infection in Adults

BACKGROUND & AIMS

Helicobacter pylori infection is increasingly difficult to treat. The purpose of these consensus statements is to provide a review of the literature and specific, updated recommendations for eradication therapy in adults.

METHODS

A systematic literature search identified studies on H pylori treatment. The quality of evidence and strength of recommendations were rated according to the Grading of Recommendation Assessment, Development and Evaluation (GRADE) approach. Statements were developed through an online platform, finalized, and voted on by an international working group of specialists chosen by the Canadian Association of Gastroenterology.

RESULTS

Because of increasing failure of therapy, the consensus group strongly recommends that all H pylori eradication regimens now be given for 14 days. Recommended first-line strategies include concomitant nonbismuth quadruple therapy (proton pump inhibitor [PPI] + amoxicillin + metronidazole + clarithromycin [PAMC]) and traditional bismuth quadruple therapy (PPI + bismuth + metronidazole + tetracycline [PBMT]). PPI triple therapy (PPI + clarithromycin + either amoxicillin or metronidazole) is restricted to areas with known low clarithromycin resistance or high eradication success with these regimens. Recommended rescue therapies include PBMT and levofloxacin-containing therapy (PPI + amoxicillin + levofloxacin). Rifabutin regimens should be restricted to patients who have failed to respond to at least 3 prior options.

CONCLUSIONS

Optimal treatment of H pylori infection requires careful attention to local antibiotic resistance and eradication patterns. The quadruple therapies PAMC or PBMT should play a more prominent role in eradication of H pylori infection, and all treatments should be given for 14 days.

Comparison of vonoprazan and proton pump inhibitors for eradication of Helicobacter pylori

Alternative eradication therapies for Helicobacter pylori infection are needed because of an increasing failure rate over the past decade. The aim of this study was to determine if vonoprazan, a new potassium-competitive acid blocker, showed superiority to existing proton pump inhibitors for primary eradication of H. pylori in routine clinical practice. Data for 573 patients who underwent primary H. pylori eradication therapy were retrospectively reviewed. Regimens included clarithromycin 200 mg, amoxicillin 750 mg, and an acid-suppressing drug [lansoprazole 30 mg (LAC), rabeprazole 10 mg (RAC), esomeprazole 20 mg (EAC), or vonoprazan 20 mg (VAC)] twice daily for 1 week. Eradication was successful in 73% (419/573) of patients using intention-to-treat (ITT) analysis and 76% (419/549) of patients in per-protocol (PP) analysis. The VAC group had a significantly superior eradication rate compared with the LAC and RAC groups in ITT (VAC 83%, LAC 66% and RAC 67%, p < 0.01) and PP analysis (VAC 85%, LAC 69% and RAC 70%, p < 0.01), and had a similarly high eradication rate to the EAC group (83% in ITT and 87% in PP). Although the eradication rate in the VAC and EAC groups was not significantly higher than in the LAC and RAC groups in patients with mild gastric atrophy with both ITT and PP analyses, it was significantly higher in patients with severe gastric atrophy (p < 0.01). The VAC group had a significantly higher H. pylori eradication rate than the LAC and RAC groups, and a > 80% eradication rate regardless of the degree of atrophy.