A Population Pharmacokinetic Model of Vonoprazan: Evaluating the Effects of Race, Disease Status, and Other Covariates on Exposure

Generation of realistic virtual adult populations using a model-based copula approach

Incorporating realistic sets of patient-associated covariates, i.e., virtual populations, in pharmacometric simulation workflows is essential to obtain realistic model predictions. Current covariate simulation strategies often omit or simplify dependency structures between covariates. Copula models are multivariate distribution functions suitable to capture dependency structures between covariates with improved performance compared to standard approaches. We aimed to develop and evaluate a copula model for generation of adult virtual populations for 12 patient-associated covariates commonly used in pharmacometric simulations, using the publicly available NHANES database, including sex, race-ethnicity, body weight, albumin, and several biochemical variables related to organ function. A multivariate (vine) copula was constructed from bivariate relationships in a stepwise fashion. Covariate distributions were well captured for the overall and subgroup populations. Based on the developed copula model, a web application was developed. The developed copula model and associated web application can be used to generate realistic adult virtual populations, ultimately to support model-based clinical trial design or dose optimization strategies.

Population pharmacokinetic analysis of zastaprazan (JP-1366), a novel potassium-competitive acid blocker, in patients and healthy volunteers

Zastaprazan (JP-1366) is a novel potassium-competitive acid blocker for the treatment of acid-related disorders. We aimed to establish a population pharmacokinetic (PK) model of zastaprazan, thereby characterizing the PK of zastaprazan in patients with gastroesophageal reflux disease (GERD) as well as evaluating the impact of various covariates, including CYP2C19 phenotypes, on zastaprazan PK. This population PK analysis included zastaprazan plasma concentration-time data from 92 patients with erosive GERD and 68 healthy volunteers without any gastrointestinal disorders and was performed using nonlinear mixed-effect modeling. Simulations were conducted to predict zastaprazan PK under various dosing regimens in patients with GERD. The plasma PK of zastaprazan was adequately described by a two-compartment model with Erlang-type absorption (six sequential compartments) and first-order elimination. CYP2C19 phenotypes had no significant effect on zastaprazan PK. The disease status was identified as a significant covariate on apparent clearance of zastaprazan, showing lower values in patients with GERD compared to healthy volunteers. However, the model-based simulation indicated that the impact of disease status on zastaprazan exposure was not clinically meaningful. Overall, the current population PK model successfully characterized the observed zastaprazan PK in both patients with GERD and healthy volunteers.

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.

Safety of potassium-competitive acid blockers in the treatment of gastroesophageal reflux disease

INTRODUCTION

Proton pump inhibitors (PPIs) are the first-line treatment for gastroesophageal reflux disease (GERD). However, due to their intrinsic limitations, there are still unmet clinical needs that have fostered the development of potassium-competitive acid blockers (P-CABs). Currently, four different drugs (vonoprazan, tegoprazan, fexuprazan, and keverprazan) are marketed in some Asian countries, whereas only vonoprazan and tegoprazan are available in Western countries (USA and Brazil or Mexico, respectively).

AREAS COVERED

This review summarizes the current knowledge on P-CABs acute and long-term safety in GERD treatment compared to that of PPIs. Full-text articles and abstracts were searched in PubMed.

EXPERT OPINION

P-CABs proved to address some of the unmet clinical needs in GERD, with a favorable risk-benefit ratio compared to conventional PPIs. Preclinical and clinical findings have highlighted P-CAB safety to be superimposable, to that of PPIs, in short-term treatments, although further studies are warranted to monitor their effects in long-term therapy. From an epidemiological point of view, the paucity of rigorous data for many variables (e.g. age, ethnicity, drug interactions, comorbidities, genetic polymorphisms, interindividual susceptibility, and gut dysbiosis) deserves a worldwide framework of continuous pre/post-marketing pharmacovigilance programs to reduce potential confounding factors and accurately link acute and chronic P-CAB therapy to adverse outcomes.

A Comprehensive Review on the Efficacy and Safety of Vonoprazan in the Management of Gastric Acid-Related Diseases

Gastric acid-related diseases, including gastroesophageal reflux disease (GERD), peptic ulcer disease (PUD), and Helicobacter pylori (H. pylori) infection, present significant clinical challenges due to their prevalence and potential for severe complications. Effective management of these conditions is essential for symptom relief, mucosal healing, and prevention of complications. This review aims to evaluate the efficacy and safety of vonoprazan, a novel potassium-competitive acid blocker (P-CAB), in the treatment of gastric acid-related diseases and to compare it with traditional proton pump inhibitors (PPIs). A comprehensive analysis of clinical trials and studies was conducted to assess the effectiveness of vonoprazan in managing GERD, PUD, and H. pylori infection. The safety profile of vonoprazan was also reviewed, and comparisons were made to PPIs and other gastric acid suppressants. Vonoprazan demonstrates superior and more consistent acid suppression than PPIs, resulting in rapid and sustained symptom relief and mucosal healing. Clinical trials have shown its efficacy in treating GERD, PUD, and H. pylori infection, with higher eradication rates for H. pylori when used in combination therapies. The safety profile of vonoprazan is favorable, with fewer adverse effects and drug interactions compared to PPIs. Vonoprazan offers a promising alternative to traditional PPIs for the management of gastric acid-related diseases. Its unique mechanism of action and superior efficacy make it a valuable option for patients requiring effective and reliable acid suppression. Further research is warranted to explore its potential in broader clinical applications and to establish long-term safety data.

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.

Incidence and type of adverse events in patients taking vonoprazan: A systematic review and meta-analysis

Background

Vonoprazan, a novel acid-suppressive drug, is non-inferior to proton pump inhibitors (PPIs) for the management of gastric acid-related diseases. However, the safety of vonoprazan has not been systematically evaluated yet.

Objectives

To elucidate the incidence and type of adverse events (AEs) in patients taking vonoprazan.

Design

Systematic review and meta-analysis.

Data sources and methods

PubMed, EMBASE, and Cochrane Library databases were searched for all studies reporting the safety of vonoprazan. The incidences of any AEs, drug-related AEs, serious AEs, AEs leading to drug discontinuation, and common AEs were pooled. Odds ratios (ORs) were calculated to compare the incidence of AEs between patients taking vonoprazan and PPIs.

Results

Seventy-seven studies were included. The pooled incidences of any AEs, drug-related AEs, serious AEs, and AEs leading to drug discontinuation were 20, 7, 1, and 1%, respectively. The incidences of any AEs (OR = 0.96, p = 0.66), drug-related AEs (OR = 1.10, p = 0.44), serious AEs (OR = 1.14, p = 0.36), and AEs leading to drug discontinuation (OR = 1.09, p = 0.55) were not significantly different between patients taking vonoprazan and PPIs. In subgroup analyses, patients with peptic ulcer disease (PUD) had higher incidences of any AEs, serious AEs, and AEs leading to drug discontinuation than those with gastroesophageal reflux disease (GERD), Helicobacter pylori (H. pylori) infection, and artificial ulcer after gastric endoscopic submucosal dissection (ESD), but patients with H. pylori infection had a higher incidence of drug-related AEs than those with PUD, GERD, and artificial ulcer after gastric ESD. The incidence of AEs was higher in patients taking long-term use of vonoprazan than those taking short-term use of vonoprazan.

Conclusion

Vonoprazan is well tolerated and shows similar safety compared to PPIs. The safety of vonoprazan may be primarily influenced by its indications and duration.

Registration

PROSPERO CRD42022314982.

Why the Vonoprazan Helicobacter pylori Therapies in the US-European Trial Produced Unacceptable Cure Rates

INTRODUCTION

Helicobacter pylori infects a large percentage of the world's population and is etiologically related to gastric cancer. The U.S. Food and Drug Administration recently approved two 14-day vonoprazan-containing regimens (vonoprazan-amoxicillin with or without clarithromycin) for H. pylori infections in the United States/Europe.

METHODS

We critically reviewed the trial methods to discover why the results were unacceptable low [i.e., no regimen achieved clinically acceptable (≥ 90%) or even conditionally acceptable cure rates (≥ 85%)]. Cure rates with antibiotic susceptible strains were 84.7 for vonoprazan triple therapy, 78.5 for vonoprazan-amoxicillin, and 78.7 for lansoprazole triple therapy, respectively. As was previously shown in Japan, the benefit from adding clarithromycin to vonoprazan-amoxicillin was minimal and the majority of the clarithromycin administered was unnecessary.

RESULTS

The possible reasons for failure to achieve high cure rates discussed include (a) reduced intragastric antibiotic concentrations, (b) an increase in heteroresistance, and (c) failure to achieve an intragastric pH conducive for amoxicillin to eradicate the infection. In addition, there was no pilot study or other attempt to optimize any regimen.

CONCLUSION

The most likely reason for failure was failure to achieve high intragastric concentrations of antibiotics or to achieve an intragastric pH conducive for amoxicillin to be active. Importantly, vonoprazan triple therapy resulted in > 10 tons of unneeded clarithromycin/million courses of vonoprazan triple therapy. Antibiotic misuse combined with low cure rates suggest that vonoprazan-clarithromycin triple therapies should not be prescribed for H. pylori infection. Dual vonoprazan-amoxicillin therapy has proven effective elsewhere and after optimization may eventually prove useful in the U.S./Europe.

Potassium-Competitive Acid Blockers: Present and Potential Utility in the Armamentarium for Acid Peptic Disorders

Potassium-competitive acid blockers (PCABs) such as vonoprazan represent a novel class of acid suppressants that show tremendous promise to enhance care of acid peptic disorders. PCAB characteristics distinct from those of proton pump inhibitors-such as acid stability with dosing independent of food consumption, rapid onset of action, less variability with CYP2C19 polymorphisms, and extended half-lives-may add value in clinical practice. With recently reported data beyond Asian populations and expanding regulatory approval of PCABs, clinicians should be aware of these medications and their potential roles in the management of acid peptic disorders. This article provides an up-to-date summary of the evidence around PCABs for the treatment of gastroesophageal reflux disease (especially erosive esophagitis healing and maintenance), eosinophilic esophagitis, Helicobacter pylori infection, and peptic ulcer healing and secondary prophylaxis.

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.

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.

Scope and Limitations of Current Antibiotic Therapies against Helicobacter pylori: Reviewing Amoxicillin Gastroretentive Formulations

Even though general improvement of quality of life has happened around the globe, statistics show that gastric cancer is still a very serious medical concern in some regions of the world. A big portion of malignant neoplasms that develop inside the stomach are linked to an infection of Helicobacter pylori; in fact, this pathogen has already been categorized as a group 1 carcinogen by the World Health Organization (WHO). Still, the efficacy of current anti-H. pylori therapeutic approaches is insufficient and follows a worrying decreasing trend, mainly due to an exponential increase in resistance to key antibiotics. This work analyzes the clinical and biological characteristics of this pathogen, especially its link to gastric cancer, and provides a comprehensive review of current formulation trends for H. pylori eradication. Research effort has focused both on the discovery of new combinations of chemicals that function as optimized antibiotic regimens, and on the preparation of gastroretentive drug delivery systems (GRDDSs) to improve overall pharmacokinetics. Regarding the last topic, this review aims to summarize the latest trend in amoxicillin-loaded GRDDS, since this is the antibiotic that has shown the least bacterial resistance worldwide. It is expected that the current work could provide some insight into the importance of innovative options to combat this microorganism. Therefore, this review can inspire new research strategies in the development of efficient formulations for the treatment of this infection and the consequent prevention of gastric cancer.

Potassium-Competitive Acid Blocker and Proton Pump Inhibitor-Based Regimens for First-Line Helicobacter pylori Eradication: A Network Meta-Analysis

Background and Aims

Effective acid suppression is a crucial component of Helicobacter pylori (H. pylori) eradication regimens. Approved treatments include dual, triple, and quadruple therapies composed of certain antibiotics in combination with proton pump inhibitors (PPIs). Vonoprazan, a potassium-competitive acid blocker, provides more potent and durable acid suppression than PPIs. We compared the efficacy of vonoprazan-based therapies vs approved standard regimens using new evidence from the phase 3 pHalconHP trial in North America and Europe.

Methods

Studies reporting first-line H. pylori eradication rates from empiric treatment with Food and Drug Administration-approved therapies and vonoprazan-containing therapies were identified via bibliographic searches of systematic literature reviews and a subsequent MEDLINE/Embase search using index terms for H. pylori and eradication. Randomized controlled trials comparing 2 or more relevant comparators were included in Bayesian network meta-analyses for grouped and distinct therapies.

Results

Twenty-three distinct regimens from 42 trials including 12,773 patients were identified. Vonoprazan-based triple therapy showed the highest relative efficacy (odds ratio: 2.73, 95% credible interval 2.11, 3.54) and 72.1% probability of being the best. North American, Western, and global scenarios were largely consistent. Vonoprazan-based therapies demonstrated higher odds of H. pylori eradication than each PPI-based triple therapy. Furthermore, vonoprazan-based triple therapy was superior to bismuth subcitrate quadruple therapy (odds ratio: 1.60, 95% credible interval: 1.07, 2.38).

Conclusion

Vonoprazan-based eradication regimens represent novel treatments for H. pylori infection on a global scale, offering efficacy that, in this analysis, is superior to PPI-based triple therapy and comparable or better than bismuth quadruple therapy.