Pathogenesis of Potassium-Competitive Acid Blocker-Resistant Non-Erosive Reflux 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 scientometrics analysis and visualization of refractory gastroesophageal reflux disease

Background

Refractory gastroesophageal reflux disease (refractory GERD) is a heterogeneous disease characterized by unresponsiveness or poor efficacy to proton-pump inhibitors (PPIs). This chronic disorder substantially weakens patients' mental wellbeing and quality of life, increasing the financial burden on society. Multiple articles have been reported in this area. However, literature involving scientometric analysis of refractory GERD is absent. Therefore, it is necessary to understand the evolution of research themes and the main hotspots of refractory GERD through bibliometric methods.

Methods

All documents related to refractory GERD based on the WOS Core Collection from January 2000 to November 2023 were selected for analysis. Citespace V 6.1 R6, VOSviewer V 1.6.20, and Scimago Graphica V 1.0.38 were used to perform bibliometric analysis.

Results

We collected a total of 241 research articles from 36 countries and 322 institutions, contributed by over 1,000 authors. Over the last 20 years, the number of articles in this field has increased year by year, and since 2011, the number of publications has increased dramatically, with 85.89% of the papers. These countries are led by the United States and Japan. GUT had the highest number of citations and DIGESTION had the highest number of publications. Research on standardized diagnosis and management, mechanisms, novel monitoring methods, and innovative drugs and procedures for refractory GERD are the main topics and hotspots in this field. This study also found that neuroimmune interaction is closely related to refractory GERD, which may be a new direction for future mechanism research.

Conclusion

Our study is the first bibliometric analysis of the global literature on refractory GERD. This research provides valuable insights for researchers, enabling them to quickly understand the research frontier and hot topics of this field.

Trends in gastroesophageal reflux disease research: A bibliometric and visualized study

Background

Gastroesophageal reflux disease (GERD), a disorder resulting from the retrograde flow of gastric contents into the esophagus, affects an estimated 10-30% of the Western population, which is characterized by multifactorial pathogenesis. Over the past few decades, there have been many aspects of uncertainty regarding GERD leading to an ongoing interest in the field as reflected by a large number of publications, whose heterogeneity and variable quality may present a challenge for researchers to measure their scientific impact, identify scientific collaborations, and to grasp actively researched themes in the GERD field. Accordingly, we aim to evaluate the knowledge structure, evolution of research themes, and emerging topics of GERD research between 2012 and 2022 with the help of bibliometric approaches.

Methods

The literature focusing on GERD from 2012 to 2022 was retrieved from the Science Citation Index Expanded of the Web of Science Core Collection. The overall publication performance, the most prolific countries or regions, authors, journals and resources-, knowledge- and intellectual-networking, as well as the co-citation analysis of references and keywords, were analyzed through Microsoft Office Excel 2019, CiteSpace, and VOSviewer.

Results

A total of 8,964 publications were included in the study. The USA published the most articles (3,204, 35.74%). Mayo Clin ranked first in the number of articles published (201, 2.24%). EDOARDO SAVARINO was the most productive author (86, 0.96%). The most productive journal in this field was SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES (304, 3.39%). AMERICAN JOURNAL OF GASTROENTEROLOGY had the most co-citations (4,953, 3.30%). Keywords with the ongoing strong citation bursts were transoral incision less fundoplication, eosinophilic esophagitis, baseline impedance, and functional heartburn.

Conclusion

For the first time, we obtained deep insights into GERD research through bibliometric analysis. Findings in this study will be helpful for scholars seeking to understand essential information in this field and identify research frontiers.

Determinants of reflux perception in patients with non-erosive reflux disease who have reflux-related symptoms on potassium-competitive acid blocker therapy

BACKGROUND

This study investigated potential determinants of reflux perception in patients with non-erosive reflux disease (NERD) who had reflux-related symptoms on potassium-competitive acid blocker (P-CAB) therapy.

METHODS

This study included 23 patients with reflux-related symptoms despite P-CAB therapy. Esophageal impedance-pH monitoring was performed on P-CAB and the following potential determinants of reflux perception were investigated: reflux nadir pH value; change in pH (baseline-nadir); bolus clearance time; reflux extent; proportions of acid, weakly acidic, and weakly alkaline reflux episodes; and proportions of liquid and mixed reflux episodes.

RESULTS

Overall, ≥ 90% of all and symptomatic reflux episodes were weakly acidic reflux and 63% of symptomatic reflux episodes were reflux episodes with pH ≥ 5. There were no significant differences regarding potential determinants between symptomatic and asymptomatic reflux episodes. However, the proportion of symptomatic reflux episodes was significantly greater with pH < 5 (13.8%) than with pH ≥ 5 (9.5%) (P = 0.0431). In reflux episodes with pH < 5, the proportion of symptomatic reflux episodes was significantly greater in proximal sites (20.6%) than in distal sites (10.6%) (P = 0.0178). Conversely, in reflux episodes with pH ≥ 5, there was no significant difference regarding reflux perception according to reflux extent (proximal: 9.6% vs. distal: 9.0%, P = 0.9337).

CONCLUSIONS

In patients with P-CAB-resistant NERD, reflux symptoms were mainly caused by reflux episodes with pH ≥ 5 on P-CAB therapy. The proportions of symptomatic reflux episodes among reflux sites differed according to reflux pH value; thus, the mechanisms of reflux perception may differ according to reflux pH value.

JianpiQinghua granule reduced PPI dosage in patients with nonerosive reflux disease: A multicenter, randomized, double-blind, double-dummy, noninferiority study

BACKGROUND

Proton pump inhibitors (PPIs) play an important role in the treatment of nonerosive reflux disease (NERD), but their long-term and excessive uses have been associated with safety concerns. Chinese herbal medicine (CHM) has become a popular alternative treatment for this condition.

METHODS

A total of 204 patients were randomly assigned to the combination group or PPI group (1:1 ratio). They were given JianpiQinghua (JQ) granules (34.8 g) plus omeprazole (10 mg) plus dummy omeprazole (10 mg) or dummy JQ granules (34.8 g) plus omeprazole (20 mg) daily for 4 weeks. The primary endpoints were the rate of sufficient relief and complete resolution of GERD Q at week 4. Metabonomics and the gut microbiota were also assessed.

RESULTS

Complete resolution was observed in 40.8% of patients in the combination group and 26.8% of patients in the PPI group after 4 weeks (FAS analysis, OR, 1.88; 95% CI, 1.03-3.44; p = 0.039). Sufficient relief was observed in 50% of patients in the combination group and 43.30% of patients in the PPI group after 4 weeks (FAS analysis, OR, 1.31; 95% CI, 0.74-2.30; p = 0.35). Three patients had liver dysfunction, one of whom had a mild case and 2 of whom had moderate-to-severe cases in the combination group. Patients in the combination group showed a significant increase in richness and diversity of their gut microbiota compared with those in the PPI group. Metabonomics showed that the combination therapy could correct the glutamate metabolism pathway.

CONCLUSION

Our findings demonstrate the superior efficacy of JQ granules combined with omeprazole (10 mg) vs. omeprazole (20 mg) in terms of symptom relief in patients with NERD.

TRIAL REGISTRATION

ClinicalTrials.gov number NCT02892357. Registered on 14 February 2019.

Application of potassium competitive acid blockers in acid-related diseases

Acid-related diseases (ARDs) are common chronic diseases of the digestive system. Proton pump inhibitors (PPIs) have become the first-line drugs for the treatment of acid-related diseases. However, PPIs display some limitations in clinical application, such as short half-life, slow action, insufficient acid inhibition, pharmacological effects affected by CYP2C19 gene polymorphism, and nocturnal acid breakthrough, which lead to insufficient symptom remission of ARDs, as well as refractoriness, relapse, and even direct decline in health-related quality of life and increased economic burden. Potassium competitive acid blockers (P-CABs) are a class of novel anti-secretory drugs, which can overcome the limitations of traditional PPIs and show satisfactory acid inhibition effect and safety in clinical application. They may become a new strategy to solve the unsatisfied medical needs in the treatment of ARDs, but their potential adverse reactions remain to be monitored. In this article, we review the challenges in the treatment of acid-related diseases, and the advantages and prospects of P-CABs in the prevention and treatment of ARDs.

Efficacy of rikkunshito in patients with functional heartburn: a prospective pilot study

BACKGROUND

Although the efficacy of rikkunshito in patients with treatment-resistant non-erosive gastroesophageal reflux disease (NERD) has been reported, it is unclear for which subgroups of NERD patients (per the Rome IV criteria) rikkunshito is effective. The objective of this study was to investigate the efficacy of rikkunshito in patients with functional heartburn.

METHODS

Ten patients with functional heartburn who experienced symptoms of dyspepsia were enrolled. The patients were administered rikkunshito for 8 weeks. The frequency scale for the symptoms of GERD (FSSG), Japanese translation of quality of life in reflux and dyspepsia questionnaire (QOLRAD-J), and hospital anxiety and depression scale (HADS) were evaluated before and 4 and 8 weeks after administration. Overall treatment efficacy (OTE) was evaluated 8 weeks after administration.

RESULTS

One patient was discontinued 4 weeks after administration because of voluntary withdrawal. Total FSSG score was significantly (P = 0.039) lower 8 weeks after treatment or at discontinuation (13.2 ± 8.0) than before treatment (18.3 ± 10.7). Although QOLRAD-J score tended to increase 8 weeks after treatment or at discontinuation compared with before treatment, no significant difference was observed. HADS score did not decrease significantly 8 weeks after treatment or at discontinuation compared with before treatment. However, a correlation was found between total FSSG and HADS anxiety scores (correlation coefficient: 0.684, P = 0.027).

CONCLUSIONS

This was the first study to investigate the efficacy of rikkunshito in patients with functional heartburn. Rikkunshito may be effective in these patients.

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.