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

Structure Determination of Tegoprazan((S)-4-((5,7-difluorochroman-4-yl)oxy)-N,N,2-trimethyl-1H-benzo[d]imidazole-6-formamide) Polymorphs A and B by Laboratory X-Ray Powder Diffraction

Tegoprazan is a potassium ion-competitive acid blocker (P-CAB) and a novel inhibitor of gastric acid secretion. The compound exists in two crystalline polymorphs, A and B, whose structures had not previously been reported. In this study, both polymorphs were analyzed by liquid- and solid-state NMR, revealing identical tautomeric states. Using this information, the crystal structures were determined from laboratory powder X-ray diffraction data by simulated annealing and Rietveld refinement. Both forms were found to crystallize in the monoclinic space group P21, with Z = 4 and two independent molecules in the asymmetric unit (Z' = 2). To assess the stability and reliability of the refined structures, we attempted geometry optimization and vibrational analysis using DFT-D methods. However, due to the high conformational complexity of Z' = 2 systems, these calculations failed to converge or produced imaginary frequencies. Instead, single-point energy calculations were performed on the refined models. The resulting relative energy differences, together with solubility data, van't Hoff enthalpies, and DSC profiles, consistently indicated that Polymorph A is more stable than Polymorph B. These results highlight the challenges of structure validation via DFT-D for complex molecular crystals and demonstrate the value of integrating experimental and computational approaches for polymorph characterization.

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

Purpose

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

Methods

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

Findings

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

Conclusions

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

Comparison of Tegoprazan and Lansoprazole in Patients With Erosive Esophagitis up to 4 Weeks: A Multi-Center, Randomized, Double-Blind, Active-Comparator Phase 4 Trial

BACKGROUND

The aims of this study were to confirm the non-inferiority of tegoprazan to lansoprazole up to week 4 in patients with erosive esophagitis (EE) and to evaluate its effectiveness in rapid mucosal healing and symptom relief at week 2.

METHODS

In this multi-center, randomized, double-blind, active-comparator non-inferiority trial, 218 patients with endoscopically confirmed EE (Los Angeles Classification Grades A-D) were randomly allocated to either the tegoprazan (50 mg) or lansoprazole (30 mg) group. The primary endpoint was the cumulative proportion of patients with healed EE up to week 4, as confirmed through endoscopy. The proportion of patients with healed EE at week 2 was also evaluated. Furthermore, CYP2C19 genotypes, symptoms, safety, and tolerability were assessed.

KEY RESULTS

In the full-analysis set, 103 and 109 participants in the tegoprazan and lansoprazole groups, respectively, were analyzed. The cumulative healing rates up to week 4 were 95.2% (98/103) and 86.2% (94/109) (difference [95% confidence interval], 8.91 [1.22-16.59]; p < 0.0001 for non-inferiority and 0.0266 for superiority), while those at week 2 were 88.4% (91/103) and 82.6% (90/109) (5.78 [-3.66-15.22], p = 0.0005 for non-inferiority) for tegoprazan and lansoprazole, respectively. Tegoprazan showed consistent healing rates regardless of CYP2C19 genotypes.

CONCLUSIONS AND INFERENCES

Tegoprazan was superior to lansoprazole in the treatment of EE up to 4 weeks. Further studies are necessary to confirm these findings and clarify the superiority of tegoprazan, especially in the treatment of severe EE.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT05267743.

How ligands modulate the gastric H,K-ATPase activity and its inhibition by tegoprazan

The introduction of potassium-competitive acid blockers (P-CABs) has been a major innovation in gastric H,K-ATPase inhibition and many laboratories are actively engaged in the development of novel molecules within this class. This work investigates the interaction between H,K-ATPase and tegoprazan, a representative of the P-CABs group, in terms of K+ and H+ binding, through functional and structural analyses. First, by studying the H,K-ATPase activity, we found a model to describe the non-Michaelis-Menten kinetics through a "ping-pong" mechanism that explains a stoichiometry of 1 H+, 1 K+, and 1 ATP molecule, but also considering the influence of H+ on the ionization states of the protein. A kinetic evaluation of the inhibition of tegoprazan denotes the binding to two different intermediates states with apparent Kd (μM) 0.56 ± 0.04 and 2.70 ± 0.24 at pH 7.2. Molecular dynamics simulations revealed important changes in the interactions of tegoprazan with the transmembrane residues depending on whether the site contains K+ or not. This explains the decrease in affinity as a function of K+ concentration observed in the kinetic experiments. On the other hand, the structures predict that the protonation of tegoprazan is responsible for the change in its dihedral angle. The rotation of the benzimidazole ring allows the inhibitor to be positioned further into the luminal cavity, a situation compatible with the higher inhibition affinity of H,K-ATPase measured at low pH. Results presented herein will provide a basis for the rational design of novel P-CABs ligands.

Comparative Efficacy and Safety of Potassium-Competitive Acid Blockers and Proton Pump Inhibitors for First-Line Helicobacter pylori Eradication Therapy: A Systematic Review and Network Meta-Analysis

BACKGROUND

Given the increasing antibiotic resistance and the inadequate acid-suppressing effects of proton pump inhibitors (PPIs), it is crucial to continuously optimize existing Helicobacter pylori (H. pylori) treatment regimens. This study aimed to evaluate the clinical efficacy and safety of novel potassium-competitive acid blocker (P-CAB)-based eradication regimens compared with traditional PPI-based regimens for the initial treatment of H. pylori.

MATERIALS AND METHODS

We conducted a systematic review and network meta-analysis, searching seven electronic databases for randomized controlled trials (RCTs) evaluating initial P-CAB-based H. pylori eradication therapy. The primary outcome was the H. pylori eradication rate. Secondary outcomes included adverse events and patient compliance. We synthesized the effect sizes of the trials using odds ratios (OR) and 95% confidence intervals (95% CI).

RESULTS

A total of 54 RCTs involving 15,320 patients (74.9% male, mean age 30.2 years) were included in this study. In the intention-to-treat (ITT) analysis, VPZ-HD-dual, VPZ-triple, and VPZ-quadruple regimens demonstrated significantly higher eradication rates than PPI-triple, PPI-quadruple, and VPZ-dual regimens. Similar trends were observed in the per-protocol (PP) analysis. Subgroup analysis indicated that poor patient compliance significantly reduced eradication rates. Resistance to clarithromycin and metronidazole significantly weakened the eradication effects of PPI-triple, TPZ-triple, and VPZ-triple regimens. Additionally, the eradication rates for 7-day regimens were significantly lower than those for 14-day or 10-day regimens, but there was no significant difference between the eradication rates of 10-day and 14-day regimens. Notably, the risk of adverse events with VPZ-HD-dual was significantly lower than with VPZ-quadruple.

CONCLUSION

Vonoprazan combined with high-dose amoxicillin dual therapy not only provides satisfactory eradication rates but also exhibits lower adverse event rates and good patient compliance, indicating its potential as a promising regimen for further promotion.

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.

Anti-Inflammatory Effects of Tegoprazan in Lipopolysaccharide-Stimulated Bone-Marrow-Derived Macrophages

The purpose of this study was to investigate the anti-inflammatory effect of tegoprazan (TEGO) in lipopolysaccharide (LPS)-stimulated bone-marrow-derived macrophages (BMMs). To this end, compared to methylprednisolone (MP; positive control), we evaluated whether TEGO effectively differentiates LPS-stimulated BMMs into M2-phenotype macrophages. Moreover, the expression of pro- and anti-inflammatory cytokines genes influenced by TEGO was measured using quantitative real-time polymerase chain reaction (qRT-PCR) analysis. TEGO was found to reduce nitric oxide (NO) production in BMMs significantly. In addition, TEGO significantly decreased and increased the gene expression levels of pro-inflammatory and anti-inflammatory cytokines, respectively. In addition, we evaluated the phosphorylated values of the extracellular signal-regulatory kinase (ERK) and p38 in the mitogen-activated protein (MAP) kinase signaling pathway through Western blotting. TEGO significantly reduced the phosphorylated values of the ERK and p38. In other words, TEGO suppressed the various pro-inflammatory responses in LPS-induced BMMs. These results show that TEGO has the potential to be used as an anti-inflammatory agent.

Deep learning driven de novo drug design based on gastric proton pump structures

Existing drugs often suffer in their effectiveness due to detrimental side effects, low binding affinity or pharmacokinetic problems. This may be overcome by the development of distinct compounds. Here, we exploit the rich structural basis of drug-bound gastric proton pump to develop compounds with strong inhibitory potency, employing a combinatorial approach utilizing deep generative models for de novo drug design with organic synthesis and cryo-EM structural analysis. Candidate compounds that satisfy pharmacophores defined in the drug-bound proton pump structures, were designed in silico utilizing our deep generative models, a workflow termed Deep Quartet. Several candidates were synthesized and screened according to their inhibition potencies in vitro, and their binding poses were in turn identified by cryo-EM. Structures reaching up to 2.10 Å resolution allowed us to evaluate and re-design compound structures, heralding the most potent compound in this study, DQ-18 (N-methyl-4-((2-(benzyloxy)-5-chlorobenzyl)oxy)benzylamine), which shows a Ki value of 47.6 nM. Further high-resolution cryo-EM analysis at 2.08 Å resolution unambiguously determined the DQ-18 binding pose. Our integrated approach offers a framework for structure-based de novo drug development based on the desired pharmacophores within the protein structure.

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

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

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

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

Structural Basis for Binding of Potassium-Competitive Acid Blockers to the Gastric Proton Pump

As specific inhibitors of the gastric proton pump, responsible for gastric acidification, K⁺-competitive acid blockers (P-CABs) have recently been utilized in the clinical treatment of gastric acid-related diseases in Asia. However, as these compounds have been developed based on phenotypic screening, their detailed binding poses are unknown. We show crystal and cryo-EM structures of the gastric proton pump in complex with four different P-CABs, tegoprazan, soraprazan, PF-03716556 and revaprazan, at resolutions reaching 2.8 Å. The structures describe molecular details of their interactions and are supported by functional analyses of mutations and molecular dynamics simulations. We reveal that revaprazan has a novel binding mode in which its tetrahydroisoquinoline moiety binds deep in the cation transport conduit. The mechanism of action of these P-CABs can now be evaluated at the molecular level, which will facilitate the rational development and improvement of currently available P-CABs to provide better treatment of acid-related gastrointestinal diseases.

Potassium tert-Butoxide Facilitated Amination of Carboxylic Acids with N,N-Dimethylformamide

Herein a practical and efficient potassium tert-butoxide (KO t Bu)-facilitated amination of carboxylic acids with N,N-dimethylamine is described. In the presence of catalytic amount of KO t Bu, a variety of aliphatic and aromatic carboxylic acids are transformed to N,N-dimethylamides using DMF as the dimethylamine reagent with the assistance of trimethylacetic anhydride. The applicability of this protocol is demonstrated by late-stage dimethylamidation of complex drug molecules. A plausible reaction mechanism involving KO t Bu-facilitated in situ amine generation from formamide decomposition and anhydride-mediated condensation is proposed on the basis of mechanistic investigations.

2020 Seoul Consensus on the Diagnosis and Management of Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is a condition in which gastric contents regurgitate into the esophagus or beyond, resulting in either troublesome symptoms or complications. GERD is heterogeneous in terms of varied manifestations, test findings, and treatment responsiveness. GERD diagnosis can be established with symptomatology, pathology, or physiology. Recently the Lyon consensus defined the "proven GERD" with concrete evidence for reflux, including advanced grade erosive esophagitis (Los Angeles classification grades C and or D esophagitis), long-segment Barrett's mucosa or peptic strictures on endoscopy or distal esophageal acid exposure time > 6% on 24-hour ambulatory pH-impedance monitoring. However, some Asian researchers have different opinions on whether the same standards should be applied to the Asian population. The prevalence of GERD is increasing in Asia. The present evidence-based guidelines were developed using a systematic review and meta-analysis approach. In GERD with typical symptoms, a proton pump inhibitor test can be recommended as a sensitive, cost-effective, and practical test for GERD diagnosis. Based on a meta-analysis of 19 estimated acid-exposure time values in Asians, the reference range upper limit for esophageal acid exposure time was 3.2% (95% confidence interval, 2.7-3.9%) in the Asian countries. Esophageal manometry and novel impedance measurements, including mucosal impedance and a post-reflux swallow-induced peristaltic wave, are promising in discrimination of GERD among different reflux phenotypes, thus increasing its diagnostic yield. We also propose a long-term strategy of evidence-based GERD treatment with proton pump inhibitors and other drugs.

Safety, Tolerability and Pharmacokinetics of Single Ascending and Multiple Oral Doses of Tegoprazan in Healthy Chinese Subjects

BACKGROUND AND OBJECTIVES

Tegoprazan is one of the potassium-competitive acid blockers (P-CABs). It exhibits its anti-secretory effects by competitively and reversibly blocking the availability of K⁺ of the H⁺, K⁺-ATPase. This study was designed to investigate the safety and pharmacokinetics of tegoprazan in healthy Chinese subjects.

METHODS

Thirty-eight healthy Chinese subjects were recruited in this randomized, single-center, double-blind, placebo-controlled study, with a single ascending dose of 50, 100, 200 mg and a multiple dose of 100 mg for 10 days. The plasma concentration of tegoprazan was determined by a validated liquid chromatography tandem mass spectrometry (LC-MS/MS) method. Pharmacokinetics were evaluated via non-compartmental and compartmental model analysis. Safety was assessed by physical examinations, vital signs, clinical laboratory tests, and electrocardiograms.

RESULTS

No serious adverse event was observed in this study. After single-dose administration (50, 100 and 200 mg), tegoprazan was rapidly absorbed with a median maximum measure plasma concentration (T_max) at 0.5 h and declined with a terminal (elimination) half-life (t_1/2) of 3.87-4.57 h. The maximum measured plasma concentration (C_max) for tegoprazan was 813.80, 1494.60 and 2829.00 ng/mL. Meanwhile, the corresponding area under the concentration-time curve (AUC) from time zero to infinity (AUC_0-inf) was 2761.00, 5980.05 and 11,044.72 ng∙h/mL in 50, 100, 200 mg group, respectively. Dose-dependent increase was observed in the value of C_max and AUC after administration of tegoprazan 50 to 200 mg. The two-compartment model well described the pharmacokinetic profile of tegoprazan. In the steady state, no accumulation was found after repeated administration at the 100-mg dose level. No experimental differences were found based on gender.

CONCLUSIONS

Tegoprazan was well tolerated in the dose range of 50-200 mg in single- and 100 mg in multiple-dose studies. Tegoprazan shows dose linearity with oral administration after a single dose of 50 to 200 mg and less drug accumulation after 10 days of continuous administration in 100 mg.

Revaprazan prevented indomethacin-induced intestinal damages by enhancing tight junction related mechanisms

Non-steroidal anti-inflammatory drugs (NSAIDs) are the most commonly prescribed medications for alleviating pain and inflammation but may cause gastrointestinal tract damage. Proton pump inhibitors (PPI) prevent NSAID-induced gastric damage but may aggravate intestinal damage via dysbiosis and intestinal permeability alteration. Currently, there is growing interest regarding the influence of potassium competitive acid blockers (PCAB) on NSAID-induced enteropathy. Here, we investigated the relative changes in indomethacin-induced enteropathy by combining indomethacin with pantoprazole (as PPI) or revaprazan (as PCAB). We examined intestinal permeability-related molecular changes in in vitro Caco-2 cell models and in an in vivo indomethacin-induced enteropathy rat model. Indomethacin alone or in combination with pantoprazole significantly increased relative lucifer yellow dye flux and decreased relative trans-epithelial electrical resistance and tight junction protein (TJP) expression compare to normal cells. In contrast, indomethacin combined with revaprazan significantly preserved TJPs compare to indomethacin-treated cells. MLC phosphorylation, Rho activation, and ERK activation responsible for TJP were significantly increased by indomethacin alone or a combination of indomethacin and pantoprazole but not by a combination of indomethacin and revaprazan. Intestinal damage scores significantly increased with indomethacin and pantoprazole combination but not with indomethacin and revaprazan combination. Indomethacin and pantoprazole combination significantly activated Rho-GTPase, p-MLC, and p-ERK but significantly decreased TJP expression. However, indomethacin and revaprazan combination significantly preserved TJPs and inactivated Rho-GTPase, MLC, and ERK. Hence, revaprazan rather than PPIs should be co-administered with NSAIDs to mitigate NSAID-induced intestinal damage.

Randomised clinical trial: tegoprazan, a novel potassium-competitive acid blocker, or lansoprazole in the treatment of gastric ulcer

BACKGROUND

Tegoprazan is a novel potassium-competitive acid blocker for the treatment of acid-related disorders.

AIMS

To assess whether tegoprazan is non-inferior to lansoprazole in terms of efficacy and safety in patients with gastric ulcers.

METHODS

In this phase 3, double-blind, active control, multicentre study, 306 gastric ulcer patients were randomised to one of three treatment groups: tegoprazan 50 mg, tegoprazan 100 mg and lansoprazole 30 mg once daily for 4 or 8 weeks. The primary endpoint was the cumulative proportion of patients with healed ulcers confirmed by endoscopy up to 8 weeks from treatment initiation. Symptoms and safety were assessed.

RESULTS

In the full analysis set, the cumulative healing rates at week 8 were 94.8% (91/96) for the tegoprazan 50 mg, 95.0% (94/99) for the tegoprazan 100 mg and 95.7% (89/93) for the lansoprazole 30 mg groups. At week 4, the respective healing rates were 90.6% (87/96), 91.9% (91/99), and 89.2% (83/93). In per protocol analysis, 4-week healing rates were 95.4% (84/88), 94.6% (88/93) and 92.9% (79/85) for tegoprazan 50 mg, tegoprazan 100 mg and lansoprazole 30 mg, respectively. Both doses of tegoprazan were non-inferior to lansoprazole in ulcer healing at 4 and 8 weeks. The incidence of drug-related treatment-emergent adverse events did not differ among groups. The increase in serum gastrin concentration was not higher in tegoprazan-treated patients than in lansoprazole-treated patients.

CONCLUSIONS

Tegoprazan 50 or 100 mg were not inferior to lansoprazole 30 mg once daily in the treatment of gastric ulcers.

The first case of tegoprazan-induced urticaria

WHAT IS KNOWN AND OBJECTIVE

Tegoprazan induces adverse drug reactions during clinical trials; however, tegoprazan-induced urticaria has not been reported. Here, we describe the first case of this.

CASE DESCRIPTION

A 55-year-old woman presented with acute urticaria with pruritus after taking the gastro-oesophageal reflux disease medication, tegoprazan. Urticaria disappeared after tegoprazan discontinuation. In an oral provocation test, after taking 10% of tegoprazan, she developed pruritus, and after taking 30%, she developed urticaria on her back.

WHAT IS NEW AND CONCLUSION

This is the first case of urticaria induced by tegoprazan. Physicians should understand the possibility of a tegoprazan-induced hypersensitivity reactions.

Novel Therapies for Gastroesophageal Reflux Disease: Beyond Proton Pump Inhibitors

PURPOSE OF REVIEW

Despite the many areas of unmet needs in gastroesophageal reflux disease (GERD), proton pump inhibitors (PPIs) remain the cornerstone of medical therapy. However, since their introduction, the therapeutic limitations of PPIs in GERD management have been increasingly recognized.

RECENT FINDINGS

In this review we discuss the new medical, endoscopic, and surgical therapeutic modalities that have been developed over the last decade. They include the potassium-competitive acid blockers (P-CABs) which provide a rapid onset, prolonged, and profound acid suppression, mucosal protectants which promote the physiological protective barrier of the esophageal mucosa, new prokinetics and neuromodulators. There are growing numbers of novel therapeutic endoscopic techniques that are under investigation or were recently introduced into the market, further expanding our therapeutic armamentarium for GERD. The development of diverse therapeutic modalities for GERD, despite the availability of PPIs, suggests that there are many areas of unmet need in GERD that will continue and drive future exploration for novel therapies.

Simultaneous quantification of tegoprazan and its major metabolite M1 in dog plasma using liquid chromatography-tandem mass spectrometry

Tegoprazan is a novel potassium-competitive acid blocker (P-CAB) recently approved in Korea as a next-generation therapeutics for gastric acid-related diseases. In the present study, we demonstrate a simple bioanalytical liquid chromatography/tandem mass spectrometry (LC-MS/MS) method for the simultaneous quantification of tegoprazan and its major metabolite (M1) in dog plasma. The developed method is based on protein precipitation and LC-MS/MS, validated according to the regulatory guidance for bioanalytical method validation. The calibration curves were linear in the concentration range of 50 ng/mL-50 μg/mL and 5 ng/mL-5 μg/mL for tegoprazan and M1, respectively. The inter- and intra-day precisions were evaluated with a coefficient of variation of <15%, and the mean accuracy ranged 92.6%-105%. The method exhibited good sensitivity and specificity. The stability of bench-top (for 8 h), freeze-thaw (3 cycles), and processed-samples (for 24 h at 4 °C) was acceptable. Tegoprazan was stable in dog plasma for 6 weeks at -70 °C. In conclusion, we successfully established a method for the simultaneous quantification of tegoprazan and M1 in dog plasma, and the method was validated for specificity, sensitivity, linearity, matrix effects, recovery, accuracy, precision, and stability. Finally, we show that the method was successfully applied to a pharmacokinetic study in dogs.