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

Comparison of Vonoprazan Triple Therapy, Bismuth Quadruple Therapy, and Amoxicillin Therapy for Helicobacter pylori Infection: A Systematic Review

Helicobacter pylori (H. pylori) infection is a significant global health concern, leading to life-threatening gastric disorders. Despite innovation in standardised treatment protocols, it faces challenges due to rising antibiotic resistance, creating the need for alternative treatments. There is a need to synthesize evidence from recent trials to enhance knowledge in critical care practice. This review synthesizes current trial data to strengthen the understanding of the literature. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) principles. The literature was searched using text terms and controlled vocabulary, employing Boolean operators "AND," "OR," and various combinations across PubMed, Embase, and the Cochrane Library. Open-access, full-text English papers from 2014 to 2024 involving human-based studies were searched. The quality was assessed using Revised Cochrane Risk of Bias Tool for Randomized Trials, Version 2.0 (ROB 2.0), and the evidence was appraised using Grading of Recommendations Assessment, Development and Evaluation (GRADE). A total of 68 articles were retrieved through the initial search. After screening and verifying eligibility according to the pre-specified inclusion criteria, the methodological quality of 25 randomized controlled trials (RCTs) was assessed using the Cochrane Risk of Bias 2.0 tool. The GRADE tool categorised three high-ROB RCTs as "low quality." However, four RCTs had low ROB and were classified as "high quality." Eighteen RCTs had uncertain ROB, lowering the evidence by one point to "moderate quality." The study found that bismuth-quadruple therapy is an excellent first-line treatment for H. pylori infection, although its adverse effects restrict its use. Vonoprazan Triple Therapy offers a superior eradication rate with improved tolerability, making it an effective treatment option. However, high doses of amoxicillin emerge as the safest and most effective treatment, especially where clarithromycin resistance is prevalent. The management of H. pylori infection is a dynamic process. As resistance patterns evolve and new treatments are developed, it is important for healthcare providers to stay informed about emerging options. Personalized treatment, taking into account patient preferences, tolerability, and concerns about resistance, will likely continue to offer the best chance for successful eradication. Ultimately, the goal is to select the most suitable therapy for each patient, ensuring both the effectiveness and comfort of the treatment.

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.

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.

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.

Gastric development of pancreatic acinar cell metaplasia after Vonoprazan therapy in rats

BACKGROUND

Vonoprazan is a new acid-suppressing drug that received FDA approval in 2022. It reversibly inhibits gastric acid secretion by competing with the potassium ions on the luminal surface of the parietal cells (potassium-competitive acid blockers or P-CABs). Vonoprazan has been on the market for a short time and there are many clinical trials to support its clinical application. However, medical experience and comprehensive clinical data is still limited, especially on how and if, gastric histology is altered due to therapy.

METHODS

A 12-week experiment trial with 30 Wistar rats was to assess the presence of gastrointestinal morphologic abnormalities upon administration of omeprazole and vonoprazan. At six weeks of age, rats were randomly assigned to one of 5 groups: (1) saline as negative control group, (2) oral omeprazole (40 mg/kg), as positive control group, (3) oral omeprazole (40 mg/kg) for 4 weeks, proceeded by 8 weeks off omeprazole, (4) oral vonoprazan (4 mg/kg), as positive control group, and (5) oral vonoprazan (4 mg/kg) for 4 weeks, proceeded by 8 weeks off vonoprazan.

RESULTS

We identified non-inflammatory alterations characterized by parietal (oxyntic) cell loss and chief (zymogen) cell hyperplasia and replacement by pancreatic acinar cell metaplasia (PACM). No significant abnormalities were identified in any other tissues in the hepatobiliary and gastrointestinal tracts.

CONCLUSION

PACM has been reported in gastric mucosa, at the esophagogastric junction, at the distal esophagus, and in Barrett esophagus. However, the pathogenesis of this entity is still unclear. Whereas some authors have suggested that PACM is an acquired process others have raised the possibility of PACM being congenital in nature. Our results suggest that the duration of vonoprazan administration at a dose of 4 mg/kg plays an important role in the development of PACM.

Development and Verification of a Japanese Pediatric Physiologically Based Pharmacokinetic Model with Emphasis on Drugs Eliminated by Cytochrome P450 or Renal Excretion

Physiologically based pharmacokinetic (PBPK) models are useful in bridging drug exposure in different ethnic groups, and there is increasing regulatory application of this approach in adults. Reported pediatric PBPK models tend to focus on the North European population, with few examples in other ethnic groups. This study describes the development and verification of a Japanese pediatric PBPK population. The development of the model was based on the existing North European pediatric population. Japanese systems and clinical data were collated from public databases and the literature, and the underlying demographics and equations were optimized so that physiological outputs represented the Japanese pediatric population. The model was tested using 14 different small molecule drugs, eliminated by a variety of pathways, including cytochrome P450 3A4 (CYP3A4) metabolism and renal excretion. Given the limitations of the clinical data, the overall performance of the model was good, with 44/62 predictions for PK parameters (area under the plasma drug concentration-time curve, AUC; maximum serum concentration, Cmax ; clearance, CL) being within 0.8- to 1.25-fold, 56/62 within 0.67- to 1.5-fold, and 61/62 within 0.5- to 2.0-fold of the observed values. Specific results for the 5 CYP3A4 substrates showed 20/31 cases were predicted within 0.8- to 1.25-fold, 27/31 within 0.67- to 1.5-fold, and all were within 0.5- to 2.0-fold of the observed values. Given the increased regulatory use of pediatric PBPK in drug development, expanding these models to other ethnic groups are important. Considering qualifying these models based on the context of use, there is a need to expand on the current research to include a larger range of drugs with different elimination pathways. Collaboration among academic, industry, model providers, and regulators will facilitate further development.

Physiologically based pharmacokinetic modeling to assess the drug-drug interactions of anaprazole with clarithromycin and amoxicillin in patients undergoing eradication therapy of H. pylori infection

OBJECTIVE

This study aimed to assess the pharmacokinetic (PK) interactions of anaprazole, clarithromycin, and amoxicillin using physiologically based pharmacokinetic (PBPK) models.

METHODS

The PBPK models for anaprazole, clarithromycin, and amoxicillin were constructed using the GastroPlus™ software (Version 9.7) based on the physicochemical data and PK parameters obtained from literature, then were optimized and validated in healthy subjects to predict the plasma concentration-time profiles of these three drugs and assess the predictive performance of each model. According to the analysis of the properties of each drug, the developed and validated models were applied to evaluate potential drug-drug interactions (DDIs) of anaprazole, clarithromycin, and amoxicillin.

RESULTS

The developed PBPK models properly described the pharmacokinetics of anaprazole, clarithromycin, and amoxicillin well, and all predicted PK parameters (Cmax,ss, AUC0-τ,ss) ratios were within 2.0-fold of the observed values. Furthermore, the application of these models to predict the anaprazole-clarithromycin and anaprazole-amoxicillin DDIs demonstrates their good performance, with the predicted DDI Cmax,ss ratios and DDI AUC0-τ,ss ratios within 1.25-fold of the observed values, and all predicted DDI Cmax,ss, and AUC0-τ,ss ratios within 2.0-fold. The simulated results show no need to adjust the dosage when co-administered with anaprazole in patients undergoing eradication therapy of H. pylori infection since the dose remained in the therapeutic range.

CONCLUSION

The whole-body PBPK models of anaprazole, clarithromycin, and amoxicillin were built and qualified, which can predict DDIs that are mediated by gastric pH change and inhibition of metabolic enzymes, providing a mechanistic understanding of the DDIs observed in the clinic of clarithromycin, amoxicillin with anaprazole.

The efficacy and safety of vonoprazan-amoxicillin dual therapy in eradicating Helicobacter pylori: a systematic review and meta-analysis

AIM

To evaluate the efficacy and safety of vonoprazan-amoxicillin (VA) dual therapy for radically eradicating Helicobacter pylori (H. pylori).

METHODS

The PubMed, Cochrane Library, Embase, China National Knowledge  Infrastructure (CNKI) and Wanfang databases were searched up to July 7, 2022, to identify clinical trials comparing the efficacy of VA dual therapy and triple therapy for H. pylori eradication. After evaluating the quality of the included studies, random effects models were conducted, and risk ratios (RRs) with 95% confidence intervals (CIs) were calculated to estimate the efficacy and safety of each approach.

RESULTS

Six publications (including four randomized controlled trials) involving 2019 patients were included in this meta-analysis. Overall, the eradication rate for VA dual therapy was 89.9%, while it was 85.2% for triple therapy based on other acid inhibitors. The eradication rate of H. pylori in the VA dual regimen group was higher than that in the PPI-based (omeprazole or lansoprazole) triple therapy group (RR = 1.15, 95% CI 1.07-1.23, p < 0.0001). However, the efficacy of VA dual therapy was comparable with VA-Clarithromycin (VAC) triple therapy (RR = 0.97, 95% CI 0.93-1.02). Besides, the incidence of adverse reactions in VA dual therapy was also lower than that in triple therapy (RR = 0.80, 95% CI 0.70-0.91, p = 0.0009).

CONCLUSION

Compared with PPI-based triple therapy, VA dual therapy showed a better therapeutic effect, safety and patient compliance rate for eradicating H. pylori, which should be used as a novel curative strategy in the future.

Evaluation of pharmacokinetic drug-drug interaction between tegoprazan and clarithromycin in healthy subjects

Tegoprazan is a novel potassium-competitive acid blocker that treats gastric acid-related diseases. Clarithromycin was widely used as one of various regimens for eradicating Helicobacter pylori. This study compared the pharmacokinetic and safety profile of tegoprazan and clarithromycin between combination therapy and monotherapy to evaluate the potential drug-drug interaction. An open-label, randomized, 6-sequence, 3-period crossover study was conducted in 24 healthy subjects. According to the assigned sequence, the subject was administered the assigned treatment during 5 days in each period. PK parameters of tegoprazan and clarithromycin administered in combination were compared with those of the respective monotherapies. The co-administration of tegoprazan with clarithromycin increased maximum steady-state plasma concentration (C_ss,max) and area under the plasma concentration-time curve in dosing interval at steady-state (AUC_ss,tau) of tegoprazan (1.6-fold in C_ss,max and 2.5-fold in AUC_ss,tau) and M1 (2.0-fold in C_ss,max, 2.5-fold in AUC_ss,tau) than tegoprazan alone. The C_ss,max and AUC_ss,tau of 14-hydroxyclarithromycin increased 1.8- and 2.0-fold in co-administration, respectively. The AUC_ss.tau of clarithromycin was slightly increased in co-administration, but C_ss,max was not changed. Combination of tegoprazan and clarithromycin and those of the respective monotherapies were tolerated in 24 healthy subjects. There may exist drug interaction that lead to reciprocal increase in plasma drug concentrations when tegoprazan and clarithromycin were administrated in combination and no safety concerns were raised. It is suggested that an in-depth analysis of the concentration-response relationship is necessary to determine whether these concentration changes warrant clinical action.

Trial Registration

ClinicalTrials.gov Identifier: NCT02052336.

The role of vonoprazan in patients with erosive esophagitis

Acid suppression is the primary therapy for erosive esophagitis (EE). Although proton pump inhibitors (PPIs) are considered as the first-line medication for EE, 10-20% of patients with Los Angeles C and D grade EE do not gain complete mucosal healing and symptom control despite 8-week double-dose PPI treatment. Vonoprazan is a novel potassium-competitive acid blocker (P-CAB), which blocks the H+, K+-adenosine triphosphatase enzymes in a K+-competitive and reversible manner. Vonoprazan exhibits different pharmacological and pharmacokinetic profiles from conventional PPIs, and has a rapid, potent and sustained acid inhibitory effect. In this review, we summarized and discussed current evidence regarding the role of vonoprazan in terms of mucosal healing, maintaining remission and symptom relief for the management of EE, including the initial and maintenance treatment of EE, as well as for PPI-resistant EE patients. Safety concerns and cost-effectiveness analysis of vonoprazan were also mentioned in the article. As a potent and well-tolerated acid blocker, vonoprazan has the potential to become a novel option for the management of EE.

Evaluation of commonly used cardiovascular drugs in inhibiting vonoprazan metabolism in vitro and in vivo

As a novel acid-suppressing drug, vonoprazan shows the potential to replace traditional proton-pump inhibitors. With its widespread use, some adverse effects that require further study have emerged due to drug–drug interactions. Our study is the first experiment that evaluated the drug–drug interactions of eleven common cardiovascular drugs that inhibit vonoprazan metabolism in vitro and in vivo. Rat liver microsome incubation and molecular simulation docking were applied to explore the inhibition mechanism. Amlodipine and nifedipine showed inhibitory effects on vonoprazan metabolism in both rat and human liver microsomes in the first evaluation part in vitro. The inhibition mechanism analysis results demonstrated that amlodipine and nifedipine might inhibit the metabolism of vonoprazan by a mixed type of competitive and non-competitive inhibition. However, the pharmacokinetic data of the vonoprazan prototype revealed that amlodipine affected vonoprazan in vivo while nifedipine did not. Thus, more attention should be paid when amlodipine is prescribed with vonoprazan. Furthermore, the changes in its carboxylic acid metabolites MI hinted at a complex situation. Molecular simulation suggested the CYP2B6 enzyme may contribute more to this than CYP3A4, and further inhibitory experiments preliminarily verified this speculation. In conclusion, the use of vonoprazan with cardiovascular drugs, especially amlodipine, should receive particular attention in clinical prescriptions.

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.

Evaluation of safety and pharmacokinetics of bismuth-containing quadruple therapy with either vonoprazan or lansoprazole for Helicobacter pylori eradication

Aims

Helicobacter pylori (Hp) eradication plays a key role in the treatment and prevention of peptic ulcer diseases. Increasing clarithromycin resistance in Hp necessitates more effective treatments for eradication, such as bismuth‐containing quadruple therapy. We aimed to compare the safety and pharmacokinetics (PK) of bismuth between vonoprazan‐ and lansoprazole‐containing quadruple therapy in Hp‐positive subjects.

Methods

In this randomised, double‐blind, parallel‐group study, Hp‐positive subjects were randomised to receive vonoprazan‐ or lansoprazole‐containing quadruple therapy. Each subject received vonoprazan 20 mg or lansoprazole 30 mg combined with bismuth 220 mg, clarithromycin 500 mg and amoxicillin 1000 mg twice daily for 14 days. Blood sampling and urine collection for bismuth PK were conducted predose and up to 12 hours postdose at steady‐state. The PK parameters of bismuth were derived using a noncompartmental method and compared between treatments. An exploratory breath test for Hp was conducted at screening and at the follow‐up visit on day 42. Safety was assessed by adverse event monitoring, physical examinations, vital signs, 12‐lead electrocardiograms and clinical laboratory tests.

Results

A total of 30 subjects were randomised and 26 subjects completed the study (12 in the vonoprazan group and 14 in the lansoprazole group). The systemic exposure of bismuth in the 2 treatments was comparable (~5% difference). All subjects turned negative for Hp at the follow‐up visit. No significant difference in safety profiles was noted between the 2 treatments.

Conclusion

The systemic exposure of bismuth was similar between vonoprazan‐ and lansoprazole‐containing quadruple therapy. Vonoprazan‐containing quadruple therapy was safe and well tolerated.

Seven-day vonoprazan and low-dose amoxicillin dual therapy as first-line Helicobacter pylori treatment: a multicentre randomised trial in Japan

OBJECTIVE

To date, no randomised trials have compared the efficacy of vonoprazan and amoxicillin dual therapy with other standard regimens for Helicobacter pylori treatment. This study aimed to investigate the efficacy of the 7-day vonoprazan and low-dose amoxicillin dual therapy as a first-line H. pylori treatment, and compared this with vonoprazan-based triple therapy.

DESIGN

This prospective, randomised clinical trial was performed at seven Japanese institutions. Patients with H. pylori-positive culture test and naive to treatment were randomly assigned in a 1:1 ratio to either VA-dual therapy (vonoprazan 20 mg+amoxicillin 750 mg twice/day) or VAC-triple therapy (vonoprazan 20 mg+amoxicillin 750 mg+clarithromycin 200 mg twice/day) for 7 days, with stratification by age, sex, H. pylori antimicrobial resistance and institution. Eradication success was evaluated by 13C-urea breath test at least 4 weeks after treatment.

RESULTS

Between October 2018 and June 2019, 629 subjects were screened and 335 were randomised. The eradication rates of VA-dual and VAC-triple therapies were 84.5% and 89.2% (p=0.203) by intention-to-treat analysis, respectively, and 87.1% and 90.2% (p=0.372) by per-protocol analysis, respectively. VA-dual was non-inferior to VAC-triple in the per-protocol analysis. The eradication rates in strains resistant to clarithromycin for VA-dual were significantly higher than those for VAC-triple (92.3% vs 76.2%; p=0.048). The incidence of adverse events was equal between groups.

CONCLUSION

The 7-day vonoprazan and low-dose amoxicillin dual therapy provided acceptable H. pylori eradication rates and a similar effect to vonoprazan-based triple therapy in regions with high clarithromycin resistance.

TRIAL REGISTRATION NUMBER

UMIN000034140.

Physiologically based pharmacokinetic-pharmacodynamic modeling for prediction of vonoprazan pharmacokinetics and its inhibition on gastric acid secretion following intravenous/oral administration to rats, dogs and humans

Vonoprazan is characterized as having a long-lasting antisecretory effect on gastric acid. In this study we developed a physiologically based pharmacokinetic (PBPK)-pharmacodynamic (PD) model linking to stomach to simultaneously predict vonoprazan pharmacokinetics and its antisecretory effects following administration to rats, dogs, and humans based on in vitro parameters. The vonoprazan disposition in the stomach was illustrated using a limited-membrane model. In vitro metabolic and transport parameters were derived from hepatic microsomes and Caco-2 cells, respectively. We found the most predicted plasma concentrations and pharmacokinetic parameters of vonoprazan in rats, dogs and humans were within twofold errors of the observed data. Free vonoprazan concentrations (f_u × C₂) in the stomach were simulated and linked to the antisecretory effects of the drug (I) (increases in pH or acid output) using the fomula dI/dt = k × f_u × C₂ × (I_max − I) − k_d × I. The vonoprazan dissociation rate constant k_d (0.00246 min⁻¹) and inhibition index K_I (35 nM) for H⁺/K⁺-ATPase were obtained from literatures. The vonoprazan-H⁺/K⁺-ATPase binding rate constant k was 0.07028 min⁻¹· μM⁻¹ using ratio of k_d to K_I. The predicted antisecretory effects were consistent with the observations following intravenous administration to rats (0.7 and 1.0 mg/kg), oral administration to dogs (0.3 and 1.0 mg/kg) and oral single dose or multidose to humans (20, 30, and 40 mg). Simulations showed that vonoprazan concentrations in stomach were 1000-fold higher than those in the plasma at 24 h following administration to human. Vonoprazan pharmacokinetics and its antisecretory effects may be predicted from in vitro data using the PBPK-PD model of the stomach. These findings may highlight 24-h antisecretory effects of vonoprazan in humans following single-dose or the sustained inhibition throughout each 24-h dosing interval during multidose administration.

Evaluation of pharmacokinetic interactions between amoxicillin, clarithromycin, and the potassium-competitive acid blocker YH4808 in healthy subjects

YH4808 is a novel potassium-competitive acid blocker that was developed as a therapeutic agent for gastric acid-related diseases; it may replace proton pump inhibitors, which are widely used in combination with amoxicillin and clarithromycin for Helicobacter pylori eradication. We compared the pharmacokinetic (PK) profiles and safety of amoxicillin, clarithromycin, and YH4808 used as monotherapies or in combination for evaluating potential drug interactions. An open-label, randomized, single-dose, Latin-square (4 × 4) crossover study was conducted in 32 healthy Korean volunteers. Subjects were randomly assigned to one of the 4 treatment sequences that consisted of 4 periods separated by 21-day washout intervals. PK parameters of YH4808, amoxicillin and clarithromycin administered in combination were compared with those of the respective monotherapies. The geometric mean ratios of the maximum concentration (C_max) and the area under the time-concentration curve from time zero to time of the last quantifiable concentration (AUC_last) of YH4808 increased during the triple therapy by 48.6% and 29.1%, respectively. Similarly, the C_max and AUC_last of M3 (active metabolite of YH4808) increased by 23.3% and 16.0%, respectively. The C_max and AUC_last of clarithromycin increased by 27.4% and 30.5%, and those of 14-hydroxyclarithromycin were increased by 23.1% and 32.4%, respectively. The corresponding amoxicillin values decreased during the triple therapy by 21.5% and 15.6%, respectively. There was no clinically significant change in safety assessment related to either monotherapies or triple therapy. In conclusion, amoxicillin, clarithromycin and YH4808 administered as triple therapy did not exhibit significant PK interactions and were not associated with safety issues.

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.

In Vitro Assessment of Potential for CYP-Inhibition-Based Drug-Drug Interaction Between Vonoprazan and Clopidogrel

BACKGROUND AND OBJECTIVES

It was recently proposed that CYP-mediated drug-drug interactions (DDIs) of vonoprazan with clopidogrel and prasugrel can attenuate the antiplatelet actions of the latter two drugs. Clopidogrel is metabolized to the pharmacologically active metabolite H4 and its isomers by multiple CYPs, including CYP2C19 and CYP3A4. Therefore, to investigate the possibility of CYP-based DDIs, in vitro metabolic inhibition studies using CYP probe substrates or radiolabeled clopidogrel and human liver microsomes (HLMs) were conducted in this work.

METHODS

Reversible inhibition studies focusing on the effects of vonoprazan on CYP marker activities and the formation of the [¹⁴C]clopidogrel metabolite H4 were conducted with and without pre-incubation using HLMs. Time-dependent inhibition (TDI) kinetics were also measured.

RESULTS

It was found that vonoprazan is not a significant direct inhibitor of any CYP isoforms (IC₅₀ ≥ 16 μM), but shows the potential for TDI of CYP2B6, CYP2C19, and CYP3A4/5. This TDI was weaker than the inhibition induced by the corresponding reference inhibitors ticlopidine, esomeprazole, and verapamil, based on the measured potencies (k_inact/K_I ratio and the R2 value). In a more direct in vitro experiment, vonoprazan levels of up to 10 µM (a 100-fold higher concentration than the plasma C_max of 75.9 nM after taking 20 mg once daily for 7 days) did not suppress the formation of the active metabolite H4 or other oxidative metabolites of [¹⁴C]clopidogrel in a reversible or time-dependent manner. Additionally, an assessment of clinical trials and post-marketing data suggested no evidence of a DDI between vonoprazan and clopidogrel.

CONCLUSIONS

The body of evidence shows that the pharmacodynamic DDI reported between vonoprazan and clopidogrel is unlikely to be caused by the inhibition of CYP2B6, CYP2C19, or CYP3A4/5 by vonoprazan.

Effects of proton pump inhibitors, esomeprazole and vonoprazan, on the disposition of proguanil, a CYP2C19 substrate, in healthy volunteers

AIMS

Vonoprazan, a new class of potassium-competitive proton pump inhibitors has been found to attenuate the antiplatelet function of clopidogrel in a recent clinical study, despite weak in vitro activity against CYP2C19. To elucidate the mechanism of this interaction, the present study investigated the effects of esomeprazole and vonoprazan on the pharmacokinetics of proguanil, a CYP2C19 substrate.

METHODS

Seven healthy male volunteers (CYP2C19 extensive metabolizers) received a single oral administration of 100 mg proguanil/250 mg atovaquone (control phase), oral esomeprazole (20 mg) for 5 days followed by proguanil/atovaquone (esomeprazole phase) and oral vonoprazan (20 mg) for 5 days followed by proguanil/atovaquone (vonoprazan phase). Concentrations of proguanil and its metabolite, cycloguanil, in plasma and urine in each phase were determined using liquid chromatography-tandem mass spectrometry.

RESULTS

Coadministration with proton pump inhibitors resulted in increase and decrease in the area under the plasma concentration-time curve (AUC) of proguanil and cycloguanil, respectively, significantly reducing their AUC ratio (cycloguanil/proguanil) to 0.317-fold (95% confidence interval [CI] 0.256-0.379) and 0.507-fold (95% CI 0.409-0.605) in esomeprazole phase and vonoprazan phase, respectively. Esomeprazole and vonoprazan also significantly reduced the apparent formation clearance (cumulative amount of cycloguanil in urine divided by AUC of proguanil) to 0.324-fold (95% CI 0.212-0.436) and 0.433-fold (95% CI 0.355-0.511), respectively, without significant changes in renal clearance of proguanil and cycloguanil.

CONCLUSIONS

Although further studies are needed, both esomeprazole and vonoprazan potentially inhibit CYP2C19 at clinical doses, suggesting caution in the coadministration of these drugs with CYP2C19 substrates.

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.

Second-line triple therapy in failures with vonoprazan-based triple therapy for eradication of Helicobacter pylori

Gastric acid inhibition during treatment is important for the eradication of Helicobacter pylori (H. pylori) infection. A novel potassium-competitive acid blocker, vonoprazan (VPZ), has been demonstrated to achieve high eradication rates; however, the efficacy of second-line treatment in failures of VPZ-based triple therapy has not been well studied. The aim of the current study was to determine the efficacy of VPZ in a first-line regimen for H. pylori eradication, and the efficacy of a second-line regimen using metronidazole (MTZ) in failures with the first-line regimen. Of 580 subjects enrolled in the study, 524 patients completed first-line treatment (275 patients who received VPZ and 249 patients who received LPZ). First-line regimens consisted of a combination of clarithromycin (CAM) 200 or 400 mg twice a day, amoxicillin (AMPC) 750 mg twice a day, and either LPZ 30 mg or VPZ 20 mg twice a day, administered orally for 7 days. CAM and VPZ/LPZ were replaced with metronidazole (MTZ) 250 mg and rabeprazole 10 mg in the second-line regimens. The eradication of H. pylori was assessed by the H. pylori stool antigen test. The overall first-line eradication rate with VPZ was significantly higher than that with LPZ [91.0% (250/275) vs. 84.7% (211/249), respectively, P=0.030]. The dose of CAM (400 vs. 800 mg) did not affect the eradication rate in either the VPZ or LPZ regimens. The overall eradication rates of the second-line regimens with MTZ did not differ significantly between the VPZ-failure and LPZ-failure groups [87.0% (20/23) vs. 87.9% (29/33), respectively, P=0.700]. Therefore, VPZ was significantly more effective than LPZ for first-line treatment. In patients with failure of first-line eradication therapy, successful results of second-line eradication therapy did not differ between the VPZ- and LPZ-failure groups. In conclusion, VPZ-based triple therapy should be recommended for eradication of H. pylori.

Vonoprazan: A Novel and Potent Alternative in the Treatment of Acid-Related Diseases

Although proton pump inhibitors (PPIs) have been used widely, acid-related diseases are still associated with a huge burden on the health care system. Recently, the efficacy and safety of a new acid suppressant named vonoprazan in the treatment of acid-related diseases have been evaluated by a series of studies. As a novel potassium-competitive acid blocker, vonoprazan may provide reversible acid suppression by preventing K⁺ from binding to gastric H⁺/K⁺-ATPase. It has been clinically used for the short-term treatment of gastroesophageal reflux disease (GERD), peptic ulcer disease and Helicobacter pylori (H. pylori) infection in Japan. The healing rate of GERD and gastric ulcers by vonoprazan is more than 95 and 90%, respectively; also, it is effective in curing PPI-resistant GERD. It increases H. pylori eradication rate to more than 88% as part of both first-line and second-line therapy. It is also effective in the eradication of clarithromycin-resistant H. pylori strains. All of these short-term studies show vonoprazan is safe and well-tolerated. As a safe and effective acid inhibitor, vonoprazan might be a novel alternative in the treatment of acid-related diseases.

Physiologic, pathophysiologic, and pharmacologic regulation of gastric acid secretion

PURPOSE OF REVIEW

The present review summarizes the past year's literature, both clinical and basic science, regarding physiologic and pharmacologic regulation of gastric acid secretion in health and disease.

RECENT FINDINGS

Gastric acid kills microorganisms, assists digestion, and facilitates absorption of iron, calcium, and vitamin B12. The main stimulants of acid secretion are the hormone gastrin, released from antral G cells; paracrine agent histamine, released from oxyntic enterochromaffin-like cells; and neuropeptide acetylcholine, released from antral and oxyntic intramural neurons. Gastrin is also a trophic hormone that participates in carcinogenesis. Helicobacter pylori may increase or decrease acid secretion depending upon the acuity and predominant anatomic focus of infection; most patients manifest hypochlorhydria. Despite the fact that proton pump inhibitors (PPIs) are amongst the most widely prescribed drugs, they are underutilized in patients at high risk for UGI bleeding. Although generally considered well tolerated, concerns have been raised regarding associations between PPI use and dementia, kidney disease, myocardial infarction, pneumonia, osteoporosis, dysbiosis, small bowel injury, micronutrient deficiency, and fundic gland polyps.

SUMMARY

Our understanding of the physiologic, pathophysiologic, and pharmacologic regulation of gastric secretion continues to advance. Such knowledge is crucial for improved and safe management of acid-peptic disorders.

Efficacy of Vonoprazan-Based Triple Therapy for Helicobacter pylori Eradication: A Multicenter Study and a Review of the Literature

BACKGROUND

Eradication therapies for Helicobacter pylori infection are advancing as new acid inhibitory reagents approved. The aim of this study was to assess the efficacy and safety of vonoprazan-based triple treatment.

MATERIALS AND METHODS

Triple therapy with vonoprazan and two antibiotics (amoxicillin and clarithromycin or metronidazole) received focus in this analysis. We performed a multicenter retrospective study of patients who received vonoprazan-based eradication therapy between February 2015 and February 2016 and conducted a review of the literature.

RESULTS

The eradication rate among the 799 patients in our multicenter study was 94.4% (95% confidence interval [CI] 92.6-96.2%) in the per-protocol analysis for first-line treatment (with vonoprazan 20 mg, amoxicillin 750 mg, and clarithromycin 200 or 400 mg, twice a day for 7 days) and 97.1% (95% CI 93.0-101.1%) for second-line treatment (with vonoprazan 20 mg, amoxicillin 750 mg, and metronidazole 250 mg, twice a day for 7 days). The overall incidence of adverse events was 4.4% in an intention-to-treat analysis with no patients hospitalized. In a literature review, six reports, in which 1380 patients received vonoprazan-based first-line eradication therapy, were included and were all reported by Japanese researchers. The eradication success rates in per-protocol analysis were between 85 and 93%, which was roughly the same among the studies.

CONCLUSIONS

Vonoprazan-based triple therapy was effective and safe for Helicobacter pylori eradication in real-world experience, confirmed by a multicenter study and a review of the pertinent literature.

Systematic review with meta-analysis: the efficacy of vonoprazan-based triple therapy on Helicobacter pylori eradication

BACKGROUND

In order to increase eradication rates, vonoprazan, a novel potassium-competitive acid blocker, has been used in Helicobacter pylori eradication therapy.

AIM

To summarise the results of the efficacy of vonoprazan-based triple therapy, helping clinicians to better understand the benefit of vonoprazan in the treatment of H. pylori infection.

METHODS

We conducted a systematic literature search on MEDLINE, EMBASE, and the Cochrane Library using the primary keywords "vonoprazan," "takecab", "TAK-438," "potassium," "competitive," "potassium-competitive," "Helicobacter," and "pylori." Studies were included if they evaluated the eradication rate between the vonoprazan-based and proton pump inhibitor (PPI)-based triple therapies.

RESULTS

Ten studies and 10 644 patients were evaluated. The crude H. pylori eradication rate determined by intention-to-treat analysis was 87.9% and 72.8% in the vonoprazan-based triple therapy and PPI-based triple therapy respectively. The eradication rate of the vonoprazan-based triple therapy was superior to that of the PPI-based triple therapy (pooled risk ratio [RR] [95% confidence interval (CI)]=1.19 [1.15-1.24]) In addition, there was no significant difference in dropout rate due to adverse event between the regimens (pooled RR of the vonoprazan-based triple therapy [95% CI]=0.69 [0.23-2.03]). The incidence of any adverse events also did not differ between the regimens (pooled RR [95% CI]=1.02 [0.78-1.34]).

CONCLUSIONS

The vonoprazan-based triple therapy showed superior efficacy in terms of H. pylori eradication as compared to the PPI-based triple therapy. In addition, the vonoprazan-based triple therapy showed comparable tolerability and incidence of adverse events.

Effect of Multiple Oral Doses of the Potent CYP3A4 Inhibitor Clarithromycin on the Pharmacokinetics of a Single Oral Dose of Vonoprazan: A Phase I, Open-Label, Sequential Design Study

BACKGROUND AND OBJECTIVES

This phase I, open-label, sequential design study assessed the effect of multiple oral doses of the potent cytochrome P450 (CYP) 3A4 inhibitor clarithromycin on the pharmacokinetics of a single oral dose of vonoprazan.

METHODS

During the 10-day treatment period, 16 healthy male subjects received vonoprazan 40 mg on days 1 and 8, and clarithromycin 1000 mg on days 3-9, with the pharmacokinetics of both examined. Primary endpoints included the maximum observed plasma concentration (C _max) and area under the plasma concentration-time curve (AUC) of vonoprazan and its major metabolites (M-I, M-II, M-III, and M-IV-Sul). Safety was also assessed.

RESULTS

Following administration, vonoprazan was rapidly absorbed (time to reach C _max, 2 h), consistent with its known pharmacokinetic profile. This was unchanged in the presence of clarithromycin. Plasma concentrations declined thereafter, with a mean apparent terminal elimination half-life of 7.2 h on day 1 and 9.4 h on day 8. Small-to-moderate increases (1.6- and 1.4-fold) in mean AUC and C _max of vonoprazan, respectively, were observed following clarithromycin. In contrast, AUC and C _max for vonoprazan metabolites decreased, except for M-IV-Sul, which increased approximately 2.1- and 1.5-fold, respectively. Overall, vonoprazan was well tolerated, with mild or moderate treatment-emergent adverse events occurring in six (37.5%) subjects receiving either vonoprazan and/or clarithromycin.

CONCLUSIONS

Modest increases in plasma concentrations of the potent CYP3A4 inhibitor clarithromycin and vonoprazan were observed during coadministration, however these differences were not considered clinically significant. Vonoprazan had a favorable safety and tolerability profile, and no serious adverse events were reported. CLINICALTRIALS.GOV: NCT02774902.

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.