Effect of splitting the dose of esomeprazole on gastric acidity and nocturnal acid breakthrough

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

INTRODUCTION

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Effect of Food on the Pharmacokinetics and Pharmacodynamics of a Novel Dual Delayed-Release Formulation of Esomeprazole in Healthy Subjects

A novel dual delayed-release formulation (DR) of esomeprazole was developed to prolong the effect of esomeprazole inhibiting gastric acid secretion. This study investigated the effect of food on the pharmacokinetics (PK) and pharmacodynamics (PD) of DR esomeprazole. A randomized, open-label, single-dose, 2-period, 2-sequence crossover study was conducted in healthy Korean subjects. Subjects were orally administered a single dose of 40- mg DR esomeprazole in fasted and fed states in each period. PK and PD characteristics evaluated through continuous 24-hour intragastric pH monitoring in fasted and fed states were compared between the 2 conditions. A total of 23 subjects completed the study and were included in the PK analysis. PD analysis was conducted in 21 subjects, excluding 2 subjects, because of inappropriate pH profiles. The systemic exposure of esomeprazole after a single dose of DR esomeprazole in the fed state decreased compared to that in the fasted state. However, the percentage decrease from baseline in integrated gastric acidity and the percentage of time at pH ≥4 were not significantly different between the 2 conditions. In conclusion, although the systemic exposure of esomeprazole decreased when DR esomeprazole was administered in the fed state compared to that in the fasted state, the degree of gastric acid secretion inhibition was not clinically different, regardless of food intake.

Successful Lifetime/Long-Term Medical Treatment of Acid Hypersecretion in Zollinger-Ellison Syndrome (ZES): Myth or Fact? Insights from an Analysis of Results of NIH Long-Term Prospective Studies of ZES

Analysis of the efficacy/pharmacology of long-term/lifetime medical treatment of acid hypersecretion in a large cohort of ZES patients in a prospective study. This study includes the results from all 303 patients with established ZES who were prospectively followed and received acid antisecretory treatment with either H2Rs or PPIs, with antisecretory doses individually titrated by the results of regular gastric acid testing. The study includes patients treated for short-term periods (<5 yrs), patients treated long-term (>5 yrs), and patients with lifetime treatment (30%) followed for up to 48 years (mean 14 yrs). Long-term/lifelong acid antisecretory treatment with H2Rs/PPIs can be successfully carried out in all patients with both uncomplicated and complicated ZES (i.e., with MEN1/ZES, previous Billroth 2, severe GERD). This is only possible if drug doses are individually set by assessing acid secretory control to establish proven criteria, with regular reassessments and readjustments. Frequent dose changes both upward and downward are needed, as well as regulation of the dosing frequency, and there is a primary reliance on the use of PPIs. Prognostic factors predicting patients with PPI dose changes are identified, which need to be studied prospectively to develop a useful predictive algorithm that could be clinically useful for tailored long-term/lifetime therapy in these patients.

Pharmacokinetics and Pharmacodynamics of Esomezol DR, a New Dual Delayed-Release Formulation of Esomeprazole 20 Mg or 40 Mg, in Healthy Subjects

Background

Esomeprazole, a proton pump inhibitor (PPI), is widely used to treat acid-related disorders, but it has short plasma half-life which can cause insufficient gastric acid suppression, such as nocturnal acid breakthrough. A new dual delayed-release (DR) formulation of esomeprazole (Esomezol DR), was developed to extend the duration of gastric acid suppression.

Purpose

This study aimed to evaluate the pharmacokinetics (PKs) and pharmacodynamics (PDs) of esomeprazole for the DR formulation compared to a conventional enteric-coated (EC) formulation (Nexium) in healthy male subjects.

Methods

Two randomized, open-label, multiple-dose, two-way crossover studies with esomeprazole 20 mg and 40 mg were conducted. Subjects received the DR formulation or the EC formulation once daily for 7 days in each period with a 7-day washout. Serial blood samples were collected up to 24 hours after the 1st dose, and 24-hour intragastric pH was continuously monitored before the 1st dose as baseline and after the 1st and the 7th dose.

Results

In 20 mg and 40 mg dose groups, 38 and 44 subjects completed the study, respectively. The DR formulation exhibited the dual-release pattern of esomeprazole, resulting in more sustained plasma concentration-time profiles compared to the EC formulation. The systemic exposure of esomeprazole for the DR formulation was comparable to that for the EC formulation, showing the similar area under the plasma concentration-time curve. The 24-hour gastric acid suppression was also similar between the two formulations, while the inhibition during night-time (22:00-06:00) showed a better tendency in the DR formulation.

Conclusion

The sustained exposure of esomeprazole in the DR formulation led to well-maintained and higher acid inhibition compared to the EC formulation, especially during the night-time. These results suggest that the DR formulation can be an alternative formulation to the conventional EC formulation, expecting the potential of relieving nocturnal acid-related symptoms.

Novel Esomeprazole Magnesium-Loaded Dual-Release Mini-Tablet Polycap: Formulation, Optimization, Characterization, and In Vivo Evaluation in Beagle Dogs

Esomeprazole magnesium (EMP) is a proton pump inhibitor (PPI) that reduces acid secretion. EMP has a short plasma half-life (approximately 1.3 h); hence, nocturnal acid breakthrough (NAB) frequently occurs, disturbing the patient’s nighttime comfort and sleep. We aimed to develop a novel esomeprazole magnesium-loaded dual-release mini-tablet polycap (DR polycap) with a prolonged onset time and improved bioavailability to prevent NAB. The formulation of the EPM mini-tablet core resulted in rapid drug release. The core was coated with an inner coating and an Eudragit^® L30D-55 aqueous dispersion coating to prepare the first-release mini-tablet. In addition, the core was coated with an inner coating and an aqueous dispersion of Eudragit^® S100 and Eudragit^® L100 coating to prepare the second-release mini-tablet. Each mini-tablet type was characterized using an in vitro dissolution test and microscopic examination. After testing, 10 of each mini-tablets were placed together in hard capsules to form DR polycaps. The combination of mini-tablets was optimized via in vitro release testing and in vivo pharmacokinetic studies. The AUC_0–24h of the DR polycap was similar to that of a comparable commercial product (Nexium^®); C_max was lower by approximately 50%, and T_max was extended by approximately 1.7-fold. In conclusion, DR polycap is an alternative to commercial products with improved NAB and dosing compliance because of its dual-release characteristics.

Evaluation of the pharmacokinetics of trazpiroben (TAK-906) in the presence and absence of the proton pump inhibitor esomeprazole

Trazpiroben, a dopamine D₂ /D₃ receptor antagonist under development to treat gastroparesis, displays decreasing solubility with increasing pH. This single-sequence, open-label, two-period, crossover study evaluated the effect of esomeprazole, a proton pump inhibitor that raises gastric pH, on the single-dose pharmacokinetics, safety, and tolerability of trazpiroben in healthy adults (NCT03849690). In total, 12 participants were enrolled and entered period 1 (days 1-3), receiving a single oral dose of trazpiroben 25 mg on day 1. After a 4-day washout, participants then entered period 2 (days 8-13) and received esomeprazole 40 mg once daily on days 8-12, with a single oral dose of trazpiroben 25 mg co-administered 1 h post esomeprazole dosing on day 11. Geometric mean area under the curve from time 0 extrapolated to infinity (AUC_∞ ) and maximum plasma concentration (C_max ) values were generally similar when trazpiroben was administered alone versus alongside esomeprazole (AUC_∞ , 44.03 vs. 38.85 ng h/ml; C_max , 19.76 vs. 17.24 ng/ml). Additionally, the associated geometric mean ratio (GMR; co-administration: administration alone) 90% confidence intervals (CIs) suggested no clinically meaningful difference between treatment groups (AUC_∞ , GMR 0.88, 90% CI 0.78-1.00; C_max , 0.87, 90% CI 0.70-1.09). Mean apparent first-order terminal elimination half-life values were similar between treatments, illustrating co-administration with esomeprazole had minimal effect on trazpiroben elimination. Trazpiroben was well-tolerated in healthy adults following administration alone and alongside esomeprazole, with no clinically relevant adverse events reported. The lack of evidence of any clinically meaningful drug-drug interaction supports the co-administration of esomeprazole with trazpiroben.

Refractory Gastroesophageal Reflux Disease: A Management Update

Gastroesophageal reflux disease (GERD) is one of the most frequent gastrointestinal disorders. Proton pump inhibitors (PPIs) are effective in healing lesions and improving symptoms in most cases, although up to 40% of GERD patients do not respond adequately to PPI therapy. Refractory GERD (rGERD) is one of the most challenging problems, given its impact on the quality of life and consumption of health care resources. The definition of rGERD is a controversial topic as it has not been unequivocally established. Indeed, some patients unresponsive to PPIs who experience symptoms potentially related to GERD may not have GERD; in this case the definition could be replaced with “reflux-like PPI-refractory symptoms.” Patients with persistent reflux-like symptoms should undergo a diagnostic workup aimed at finding objective evidence of GERD through endoscopic and pH-impedance investigations. The management strategies regarding rGERD, apart from a careful check of patient's compliance with PPIs, a possible change in the timing of their administration and the choice of a PPI with a different metabolic pathway, include other pharmacologic treatments. These include histamine-2 receptor antagonists (H2RAs), alginates, antacids and mucosal protective agents, potassium competitive acid blockers (PCABs), prokinetics, gamma aminobutyric acid-B (GABA-B) receptor agonists and metabotropic glutamate receptor-5 (mGluR5) antagonists, and pain modulators. If there is no benefit from medical therapy, but there is objective evidence of GERD, invasive antireflux options should be evaluated after having carefully explained the risks and benefits to the patient. The most widely performed invasive antireflux option remains laparoscopic antireflux surgery (LARS), even if other, less invasive, interventions have been suggested in the last few decades, including endoscopic transoral incisionless fundoplication (TIF), magnetic sphincter augmentation (LINX) or radiofrequency therapy (Stretta). Due to the different mechanisms underlying rGERD, the most effective strategy can vary, and it should be tailored to each patient. The aim of this paper is to review the different management options available to successfully deal with rGERD.

[Therapeutic Response to 20 mg of Esomeprazole Twice Daily in Patients with Gastroesophageal Reflux Disease-related Non-cardiac Chest Pain: An Open-Label Randomized Pilot Study]

Background/Aims

Non-cardiac chest pain (NCCP) is defined as recurrent angina pectoris-like pain without evidence of coronary heart disease, and is usually related to esophageal diseases, such as gastroesophageal reflux disease (GERD). Proton pump inhibitors (PPIs) are important for diagnosis and treatment. Many studies have been conducted on the use of PPIs in patients with GERD-related NCCP. In contrast to standard-dose esomeprazole, the efficacy of half-dose esomeprazole twice daily (BD) has not been established. This study compared the efficacies of the two esomeprazole regimens in GERD-related NCCP.

Methods

In this prospective, open-label study, 37 participants with GERD-related NCCP were randomized to receive either 20 mg of esomeprazole BD (n=21) (esomeprazole BD group) or 40 mg once daily (n=16) (esomeprazole once daily [OD] group) for 4 weeks. In both groups, the chest pain score, which was calculated based on the frequency and severity, was evaluated before and 2 and 4 weeks after administering the medication.

Results

The chest pain score significantly improved in both groups (p<0.001). The proportion of patients with chest pain score improvement >50% was 7.7% higher in the esomeprazole BD group than in the esomeprazole OD group (95.2% vs. 87.5%), but the difference was not significant.

Conclusions

Esomeprazole BD was as effective as esomeprazole OD in improving GERD-related NCCP. Although statistically insignificant, the percentage of patients with >50% reduction in the chest pain score was higher in the esomeprazole BD group than in the esomeprazole OD group. Large-scale studies will be needed to assess these findings further.

In search of the grail: A race for acid suppression

Proton pump inhibitors are the reference standards for the treatment of acid-related diseases. Acid suppression in gastroesophageal reflux disease is associated with a high rate of mucosal cicatrization, but symptom response differs among endoscopic phenotypes. Extraesophageal manifestations have a good clinical response in patients that present with abnormal acid exposure (diagnostic test) in the esophagus. Proton pump inhibitors have shown their effectiveness for reducing symptom intensity in nighttime reflux and sleep disorders, improving quality of life and work productivity. That can sometimes be achieved through dose modifications by splitting or increasing the dose, or through galenic formulation. Proton pump inhibitors are not exempt from controversial aspects related to associated adverse events. Technological development is directed at improving proton pump inhibitor performance through increasing the half-life, maximum concentration, and area under the curve of the plasma concentrations through galenic formulation, as well as creating safer and more tolerable drugs. The present review is focused on the mechanisms of action, pharmacokinetic properties, and technological advances for increasing the pharmacologic performance of a proton pump inhibitor.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Modulations in extracellular calcium lead to H+-ATPase-dependent acid secretion: a clarification of PPI failure

The H⁺,K⁺-ATPase was identified as the primary proton secretory pathway in the gastric parietal cell and is the pharmacological target of agents suppressing acid secretion. Recently, we identified a second acid secretory protein expressed in the parietal cell, the vacuolar H⁺-ATPase (V-type ATPase). The aim of the present study was to further characterize H⁺-ATPase activation by modulations in extracellular calcium via the calcium sensing receptor (CaSR). Isolated gastric glands were loaded with the pH indicator dye BCECF-AM [2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein acetoxymethyl ester] to measure intracellular pH. Experiments were conducted in the absence of sodium and potassium to monitor H⁺-ATPase-specific transport activity. CaSR was activated with the calcimimetic R568 (400 nM) and/or by modulations in extracellular Ca²⁺. Elevation in calcium concentrations increased proton extrusion from the gastric parietal cell. Allosteric modification of the CaSR via R568 and calcium increased vacuolar H⁺-ATPase activity significantly (ΔpH/min_lowCa²⁺_(0.1mM) = 0.001 ± 0.001, ΔpH/min_normalCa²⁺_(1.0mM) = 0.033 ± 0.004, ΔpH/min_highCa²⁺_(5.0mM) = 0.051 ± 0.005). Carbachol significantly suppressed calcium-induced gastric acid secretion via the H⁺-ATPase under sodium- and potassium-free conditions. We conclude that the V-type H⁺-ATPase is tightly linked to CaSR activation. We observed that proton pump inhibitor (PPI) exposure does not modulate H⁺-ATPase activity. This elevated blood calcium activation of the H⁺-ATPase could provide an explanation for recurrent reflux symptoms while taking a PPI therapy. NEW & NOTEWORTHY This study emphasizes the role of the H⁺-ATPase in acid secretion. We further demonstrate the modification of this proton excretion pathway by extracellular calcium and the activation of the calcium sensing receptor CaSR. The novelty of this paper is based on the modulation of the H⁺-ATPase via both extracellular Ca (activation) and the classical secretagogues histamine and carbachol (inactivation). Both activation and inactivation of this proton pump are independent of PPI modulation.

Interchangeable Use of Proton Pump Inhibitors Based on Relative Potency

Although proton pump inhibitors (PPIs) are widely used, their relative potency and ideal dosing regimens remain unclear. We analyzed data from randomized clinical trials that performed pH testing in patients receiving solid-dose PPI formulations (omeprazole, esomeprazole, lansoprazole, pantoprazole, rabeprazole) for a minimum of 5 days. We used omeprazole equivalency and the surrogate biomarker, percentage time pH > 4 over a 24-hour period (pH4time), to compare PPI effectiveness for different PPIs given once, twice, or 3 times daily. We found that increasing strength of once-daily PPIs (9-64 mg omeprazole equivalents) increased pH4time linearly from approximately 10.0 to 15.6 hours; higher doses produced no further increase in pH4time. Increasing the frequency to twice-daily PPI increased pH4time linearly, from approximately 15.8 to 21.0 hours. Three-times daily PPIs performed similarly to twice-daily PPIs. The costs of PPIs varied greatly, but the cost variation was not directly related to potency. We conclude that PPIs can be used interchangeably based on potency. Using twice-daily PPIs is more effective in increasing efficacy increasing once-daily PPI dosage. Omeprazole and lansoprazole (30 mg) and 20 mg of esomeprazole rabeprazole are functionally equivalent.

A novel K+ competitive acid blocker, YH4808, sustains inhibition of gastric acid secretion with a faster onset than esomeprazole: randomised clinical study in healthy volunteers

BACKGROUND

YH4808, a K⁺ -competitive acid blocker, is under clinical development for the treatment of acid-related disorders, such as gastroesophageal reflux disease.

AIMS

To determine the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of YH4808, compared to placebo and esomeprazole.

METHODS

This double-blind, randomised, placebo- and active comparator (esomeprazole)-controlled study was conducted with 123 healthy male volunteers. We evaluated YH4808 (30-800 mg) properties, administered in single (N=55) and multiple (N=24) oral doses, and recorded the effects on 24-hour intragastric acidity. Results were compared to placebo (N=20) and esomeprazole 40 mg (N=24).

RESULTS

Plasma YH4808 exposure increased dose-proportionally and declined in a multi-phasic manner. YH4808 ≥200 mg/d maintained intragastric acidity at pH >4 for longer times than esomeprazole during both day and night (%Time at pH >4: >70% vs 58% of a 24-hour period, respectively; and >50% vs 33% of a 9-hour night respectively). A twice-daily regimen of YH4808 more effectively controlled intragastric pH at night than a once-daily regimen. In evaluating the mean areas under the intragastric pH-time curves in 15-minute intervals for 2 hours after dosing, we found that YH4808 had a faster onset than esomeprazole. Moreover, unlike esomeprazole, YH4808 PK and PD were not significantly affected by the CYP2C19 genotype of the subjects. YH4808 was well-tolerated at all doses administered.

CONCLUSION

This study showed that YH4808 produced a rapid, sustained suppression of gastric secretion with good tolerability. The results at YH4808 ≥200 mg/d provide a rationale for further clinical investigations in populations with acid-related diseases.

Diagnosis and treatment of gastroesophageal reflux disease: recommendations of the Asociación Mexicana de Gastroenterología

Emerging concepts in the pathophysiology of gastroesophageal reflux disease (GERD) and the constant technologic advances in the diagnosis and treatment of this clinical condition make it necessary to frequently review and update the clinical guidelines, recommendations, and official statements from the leading academic groups worldwide. The Asociación Mexicana de Gastroenterología (AMG), aware of this responsibility, brought together national experts in this field to analyze the most recent scientific evidence and formulate a series of practical recommendations to guide and facilitate the diagnostic process and efficacious treatment of these patients. The document includes algorithms, figures, and tables for convenient consultation, along with opinions on GERD management in sensitive populations, such as pregnant women and older adults.

Gastroesophageal Acid Reflux Control 5 Years After Antireflux Surgery, Compared With Long-term Esomeprazole Therapy

BACKGROUND & AIMS

We compared the ability of laparoscopic antireflux surgery (LARS) and esomeprazole to control esophageal acid exposure, over a 5-year period, in patients with chronic gastroesophageal reflux disease (GERD). We also studied whether intraesophageal and intragastric pH parameters off and on therapy were associated with long-term outcomes.

METHODS

We analyzed data from a prospective, randomized, open-label trial comparing the efficacy and safety of LARS vs esomeprazole (20 or 40 mg/d) over 5 years in patients with chronic GERD. Ambulatory intraesophageal and intragastric 24-hour pH monitoring data were compared between groups before LARS or the start of esomeprazole treatment, and 6 months and 5 years afterward. A secondary aim was to evaluate the association between baseline and 6-month pH parameters and esomeprazole dose escalation, reappearance of GERD symptoms, and treatment failure over 5 years in patients receiving LARS or esomeprazole.

RESULTS

In the LARS group (n = 116), the median 24-hour esophageal acid exposure was 8.6% at baseline and 0.7% after 6 months and 5 years (P < .001 vs baseline). In the esomeprazole group (n = 151), the median 24-hour esophageal acid exposure was 8.8% at baseline, 2.1% after 6 months, and 1.9% after 5 years (P < .001, therapy vs baseline, and LARS vs esomeprazole). Gastric acidity was stable in both groups. Patients who required a dose increase to 40 mg/d had more severe supine reflux at baseline, and decreased esophageal acid exposure (P < .02) and gastric acidity after dose escalation. Esophageal and intragastric pH parameters, off and on therapy, did not predict long-term symptom breakthrough.

CONCLUSIONS

In a prospective study of patients with chronic GERD, esophageal acid reflux was reduced greatly by LARS or esomeprazole therapy. However, patients receiving LARS had significantly greater reductions in 24-hour esophageal acid exposure after 6 months and 5 years. Esophageal and gastric pH, off and on therapy, did not predict long-term outcomes of patients. Abnormal supine acid exposure predicted esomeprazole dose escalation. ClinicalTrials.Gov identifier: NCT00251927 (available: http://clinicaltrials.gov/ct2/show/NCT00251927).

[Underlying Mechanisms and Management of Refractory Gastroesophageal Reflux Disease]

The prevalence of gastroesophageal reflux disease (GERD) in South Korea has increased over the past 10 years. Patients with erosive reflux disease (ERD) shows better response to proton pump inhibitors (PPIs) than those with non-erosive reflux disease (NERD). NERD is a heterogeneous condition, showing pathological gastroesophageal reflux or esophageal hypersensitivity to reflux contents. NERD patients with pathological gastroesophageal reflux or hypersensitivity to acid may respond to PPIs. However, many patients with esophageal hypersensitivity to nonacid or functional heartburn do not respond to PPIs. Therefore, careful history and investigations are required when managing patients with refractory GERD who show poor response to conventional dose PPIs. Combined pH-impedance studies and a PPI diagnostic trial are recommended to reveal underlying mechanisms of refractory symptoms. For those with ongoing reflux-related symptoms, split dose administration, change to long-acting PPIs or PPIs less influenced by CYP2C19 genotypes, increasing dose of PPIs, and the addition of alginate preparations, prokinetics, selective serotonin reuptake inhibitors, or tricyclic antidepressants can be considered. Pain modulators, selective serotonin reuptake inhibitors, or tricyclic antidepressants are more likely to be effective for those with reflux-unrelated symptoms. Surgery or endoscopic per oral fundoplication may be effective in selected patients.

The effect of once daily omeprazole and succinic acid (VECAM) vs once daily omeprazole on 24-h intragastric pH

BACKGROUND

Parietal cell H(+)/K(+) ATPase activation is essential for optimal proton pump inhibitor (PPI) activity. Succinic acid (SA) was shown to induce gastric acid secretion. VECAM is a combination of omeprazole (OMP) and SA. To compare the effect of once daily bedtime dosing of VECAM 40 and VECAM 20 without food vs OMP 20 mg administered before breakfast on gastric acidity.

METHODS

Open label, randomized, crossover study enrolling 36 healthy subjects comparing the study treatments at steady state for 24 h intragastric pH monitoring.

KEY RESULTS

The median percent time intragastric pH > 4 demonstrated that VECAM 40 was superior to VECAM 20 (65.7%vs 49.1%P < 0.0001) and OMP 20 mg (65.7%vs 47.6%P = 0.005) during 24 h. VECAM 40 was superior to VECAM 20 (52.8%vs 38.8%P = 0.0079) and OMP 20 mg (52.8%vs 27.2%P < 0.0001), and VECAM 20 was superior to OMP 20 mg (38.8 vs 27.2 P = 0.0069) during the nighttime. VECAM 20 and OMP 20 mg were comparable during 24 h.

CONCLUSIONS & INFERENCES

VECAM 40 and VECAM 20 were significantly better in maintaining intragastric pH > 4 during the nighttime than OMP 20 mg. Succinic acid eliminates the need for a subsequent meal for intragastric pH control by VECAM.

The effects of dose and timing of esomeprazole administration on 24-h, daytime and night-time acid inhibition in healthy volunteers

BACKGROUND

Symptoms of gastro-oesophageal reflux disease (GERD) may persist despite daily treatment with a proton pump inhibitor (PPI).

AIM

To compare the pharmacodynamic effect of various esomeprazole dosage and timing regimens in healthy volunteers.

METHODS

The effect of different esomeprazole dosage regimens [20 mg once daily (od) before breakfast or dinner; 20 mg twice daily (b.d.); 40 mg od before breakfast, dinner or at bedtime; and 40 mg b.d.] on 24-h, daytime and night-time acid inhibition was evaluated in a randomized, seven-way crossover study in healthy volunteers. Each regimen was taken for 5 days.

RESULTS

Over the 24-h period (day 5), esomeprazole 20 mg b.d. was associated with superior acid inhibition vs. all 20 mg and 40 mg od regimens (P < 0.05), but was less effective than esomeprazole 40 mg b.d. (P < 0.05). Dosing with esomeprazole 20 mg or 40 mg od before breakfast gave improved 24-h and daytime acid inhibition vs. the corresponding administration before dinner or at bedtime (all P < 0.05). Night-time acid inhibition was improved when esomeprazole 40 mg od was administered before dinner or at bedtime vs. before-breakfast dosing (P < 0.05).

CONCLUSION

Varying the dose and timing of esomeprazole administration may provide acid inhibition appropriate for the symptom pattern of individual patients with GERD.

Relationship between esomeprazole dose and timing to heartburn resolution in selected patients with gastroesophageal reflux disease

OBJECTIVE

To increase response rates to therapy by increasing the dosage of proton pump inhibitor (PPI) therapy in patients with gastroesophageal reflux disease (GERD) whose symptoms are predominantly associated with acid reflux.

METHODS

In this double-blind, randomized, proof-of-concept study, 369 patients with GERD and moderate heartburn lasting ≥three days/week, a history of response to antacids/acid suppression therapy, and a positive esophageal acid perfusion test result were randomized to esomeprazole 20 or 40 mg once daily, or to 40 mg twice daily for four weeks. Heartburn symptom relief/resolution was subsequently evaluated.

RESULTS

In this study population, no relationship was apparent between esomeprazole dosage and efficacy variables for sustained heartburn resolution (seven days without symptoms) at week 4 (48.0%, 44.0%, and 41.4% for esomeprazole 20 mg once daily, 40 mg once daily, and 40 mg twice daily, respectively). Nocturnal heartburn resolution with esomeprazole 40 mg twice daily showed a numeric improvement trend versus esomeprazole 20 and 40 mg once daily, but this was not statistically significant.

CONCLUSIONS

Heartburn resolution rates at four weeks were similar for all esomeprazole dosages and comparable with rates reported previously, suggesting a plateau effect in terms of clinical response to acid suppression with PPI therapy in this population of selected GERD patients.

[Evidence and uncertainties on the clinical use of proton pump inhibitors]

Proton pump inhibitors (PPI) are the most potent and effective drugs for the control of gastric acid secretion and constitute one of the most widely prescribed pharmacological groups worldwide. The safety and efficacy of PPI have been demonstrated in clinical practice and these drugs are currently the treatment of choice in peptic ulcer diseases, Helicobacter pylori infection, gastroesophageal reflux disease, nonsteroidal antiinflammatory drug gastropathy and functional dyspepsia. However, despite the excellent pharmacological profile of current PPI, their rapidity of action may be insufficient in some diseases, 24-hour acid inhibition is not always achieved and - to a greater or lesser extent depending on the distinct molecules of the PPI - there is interindividual variability in gastric antisecretory efficacy, depending on genetic polymorphism of CYP2C19, which could affect individual metabolism of the distinct PPI. New generations of these drugs will probably eliminate these deficiencies.

Esomeprazole: potent acid suppression in the treatment of acid-related disorders

Esomeprazole (S-omeprazole), an enantiomer of the racemate omeprazole, is the first proton pump inhibitor to be developed as an isomer. This confers improved pharmacokinetics and pharmacodynamics compared with the racemate R/S-omeprazole. The difference in the pharmacokinetics of esomeprazole compared with omeprazole and the R-isomer is due to reductions in total body clearance and first-pass metabolism in the liver. Pharmacodynamic studies showed that esomeprazole 40 mg provides greater intragastric acid control than respective doses of all the other proton pump inhibitors on the market. Several well-designed clinical trials, employing both endoscopic and symptomatic response criteria, have compared the efficacy of esomeprazole with that of other proton pump inhibitors in the management of gastroesophageal reflux disease patients, and in the eradication of Helicobacter pylori. In addition, the efficacy of esomeprazole for the healing and prevention of nonsteroidal anti-inflammatory drug-associated dyspeptic symptoms and ulcers has been established. The aim of this review is to provide an overview of the pharmacokinetics, pharmacodynamics and consequent clinical importance of esomeprazole in the treatment of acid-related disorders.

Quantification of dental erosions in patients with GERD using optical coherence tomography before and after double-blind, randomized treatment with esomeprazole or placebo

OBJECTIVES

Dental erosion, the chemical dissolution of enamel without bacterial involvement, is a rarely reported manifestation of gastroesophageal reflux disease (GERD), as well as of recurrent vomiting and dietary habits. It leads to loss of tooth substance, hypersensitivity, functional impairment, and even tooth fracture. To date, dental erosions have been assessed using only very basic visual methods, and no evidence-based guidelines or studies exist regarding the prevention or treatment of GERD-related dental erosions.

METHODS

In this randomized, double-blind study, we used optical coherence tomography (OCT) to quantify dental tissue demineralization and enamel loss before and after 3 weeks of acid-suppressive treatment with esomeprazole 20 mg b.i.d. or placebo in 30 patients presenting to the Berne University Dental Clinic with advanced dental erosions and abnormal acid exposure by 24-h esophageal pH manometry (defined as >4% of the 24-h period with pH<4). Enamel thickness, reflectivity, and absorbance as measures of demineralization were quantified by OCT before and after therapy at identical localizations on teeth with most severe visible erosions as well as several other predefined changes in teeth.

RESULTS

The mean+/-s.e.m. decrease of enamel thickness of all teeth before and after treatment at the site of maximum exposure was 7.2+/-0.16 black trianglem with esomeprazole and 15.25+/-0.17black trianglem with placebo (P=0.013), representing a loss of 0.3% and 0.8% of the total enamel thickness, respectively. The change in optical reflectivity to a depth of 25 black trianglem after treatment was-1.122 +/-0.769 dB with esomeprazole and +2.059+/-0.534 dB with placebo (P 0.012), with increased reflectivity signifying demineralization.

CONCLUSIONS

OCT non-invasively detected and quantified significantly diminished progression of dental tissue demineralization and enamel loss after only 3 weeks of treatment with esomeprazole 20 mg b.i.d. vs. placebo. This suggests that esomeprazole may be useful in counteracting progression of GERD-related dental erosions. Further validation of preventative treatment regimens using this sensitive detection method is required, including longer follow-up and correlation with quantitative reflux measures.

Relative potency of proton-pump inhibitors-comparison of effects on intragastric pH

AIM

Comparative potency of proton-pump inhibitors (PPIs) is an important clinical issue. Most available trials have compared the different PPIs at one or a few selected specific dosages, making it difficult to derive quantitative equivalence dosages. Here we derived PPI dose equivalents based on a comprehensive assessment of dose-dependent effects on intragastric pH.

METHODS

All available clinical studies reporting the effects of PPIs on mean 24-h intragastric pH were sought from electronic databases including Medline. Studies included were restricted to those targeting the Caucasian population, and healthy volunteers or gastroesophageal reflux disease (GERD) patients. The dose-effect relationships for mean 24-h intragastric pH and for percentage of time with pH > 4 in 24 h were analyzed for each PPI using pharmacodynamic modeling with NONMEM and a model integrating all available data.

RESULTS

Fifty-seven studies fulfilled the inclusion criteria. Based on the mean 24-h gastric pH, the relative potencies of the five PPIs compared to omeprazole were 0.23, 0.90, 1.00, 1.60, and 1.82 for pantoprazole, lansoprazole, omeprazole, esomeprazole, and rabeprazole, respectively. Compared with healthy volunteers, patients with GERD needed a 1.9-fold higher dose and Helicobacter pylori-positive individuals needed only about 20% of the dose to achieve a given increase in mean 24-h intragastric pH.

CONCLUSION

The present meta-analysis provides quantitative estimates on clinical potency of individual PPIs that may be helpful when switching between PPIs and for assessing the cost-effectiveness of specific PPIs. However, our estimates must be viewed with caution because only a limited dose range has been tested and not exactly the same study conditions were applied for the different substances.

Combination of a cyclo-oxygenase-2 inhibitor and a proton-pump inhibitor for prevention of recurrent ulcer bleeding in patients at very high risk: a double-blind, randomised trial

BACKGROUND

Guidelines on pain management recommend that patients at risk of ulcers receive either a cyclo-oxygenase (COX 2) inhibitor or a non-steroidal anti-inflammatory drug (NSAID) with a proton-pump inhibitor (PPI). These two treatments have similar effectiveness, but they are insufficient for protection of patients at very high risk for ulcer bleeding. We aimed to test the hypothesis that in patients with previous ulcer bleeding induced by non-selective NSAIDs, combined treatment with the COX 2 inhibitor celecoxib and the PPI esomeprazole would be better than celecoxib alone for prevention of recurrent ulcer bleeding.

METHODS

441 consecutively presenting patients who were taking non-selective NSAIDs for arthritis were recruited to our single-centre, prospective, randomised, double-blind trial after admission to hospital with upper-gastrointestinal bleeding. Patients were enrolled after their ulcers had healed and a histological test for Helicobacter pylori was negative. All patients were given 200 mg celecoxib twice daily. 137 patients were randomly assigned to receive 20 mg esomeprazole twice daily (combined-treatment group), and 136 to receive a placebo (control group) for 12 months. The primary endpoint was recurrent ulcer bleeding during treatment or within 1 month of the end of treatment. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00365313.

FINDINGS

Combination treatment was more effective than celecoxib alone for prevention of ulcer bleeding in patients at high risk. The 13-month cumulative incidence of the primary endpoint was 0% in the combined-treatment group and 12 (8.9%) in the controls (95% CI difference, 4.1 to 13.7; p=0.0004). The median follow-up was 13 months (range 0.4-13.0). Discontinuation of treatment and the incidence of adverse events were similar in the two treatment groups.

INTERPRETATION

Patients at very high risk for recurrent ulcer bleeding who need anti-inflammatory analgesics should receive combination treatment with a COX 2 inhibitor and a PPI. Our findings should encourage guideline committees to review their recommendations for patients at very high risk of recurrent ulcer bleeding.

Comparison of the effects of fasting morning, fasting evening and fed bedtime administration of tenatoprazole on intragastric pH in healthy volunteers: a randomized three-way crossover study

BACKGROUND

The effectiveness of proton pump inhibitors is influenced by meals and administration time.

AIM

To compare the effects on intragastric acidity of times of dosing of tenatoprazole, a novel imidazopyridine-based proton pump inhibitor with a prolonged plasma half-life.

METHODS

This randomized three-period crossover study included 12 Helicobacter pylori-negative healthy subjects, who received tenatoprazole 40 mg either fasting at 7.00 AM, fasting at 7.00 PM or fed at 9.30 PM for 7 days, with a 2-week washout between periods. Twenty-four hour intragastric pH was monitored on day 7 of each period.

RESULTS

On day 7, median 24-h pH was 4.7, 5.1 and 4.7 after breakfast, dinner and bedtime dosing, respectively (P = 0.11), whereas night-time pH was 4.2, 5.0 and 4.4 (P = 0.13). The mean 24-h percentage of time over pH 4 was 62, 72 and 64 after breakfast, dinner and bedtime dosing, respectively (N.S.), and 54, 68 and 56 during night-time (P = 0.06). Nocturnal acid breakthrough incidence decreased from 100% at baseline to 83%, 55% and 75% after 7.00 AM, 7.00 PM and 9.30 PM dosing, respectively (P = 0.18), and its mean duration dropped from 6.2 to 2.8, 1.0 and 2.2 h, respectively (P < 0.05).

CONCLUSION

Seven-day administration of tenatoprazole provides a prolonged duration of acid suppression, especially during the night-time, with little effect of food or time of dosing.

Optimising acid inhibition treatment

Acid inhibition is safe and useful in several clinical settings. Proton pump inhibitors are more effective than H2-receptor antagonists in virtually all cases. Proton pump inhibitors should be used in: the eradication of Helicobacter pylori; the treatment of non-H. pylori-related peptic ulcer healing; for the prevention and treatment of non-steroidal anti-inflammatory drug-induced upper digestive lesions; for bleeding peptic lesions; and, especially, in the short-term and long-term control of gastro-oesophageal reflux disease. The timing, the dosing and the specific drugs should be adapted to the particular patient, clinical situation and local factors. For instance, in a patient with active bleeding from a duodenal ulcer, intravenous constant infusion should be the preferred treatment. When seeking oral 'potent' acid inhibition (refractory gastro-oesophageal reflux disease, and perhaps Barrett's oesophagus), available data suggest that the pharmacological and clinical profiles of esomeprazole are slightly better.

Review article: putting immediate-release proton-pump inhibitors into clinical practice--improving nocturnal acid control and avoiding the possible complications of excessive acid exposure

Nocturnal gastro-oesphageal reflux is an under-appreciated clinical challenge. This condition may cause symptoms such as nocturnal heartburn, or it may be asymptomatic. In addition, patients may experience sleep disturbances that can potentially lead to complications such as erosive oesophagitis and Barrett's oesophagus, and may be a risk factor for development of oesophageal adenocarcinoma. Delayed-release proton-pump inhibitors (PPIs) have traditionally been effective in treating both daytime and night-time reflux symptoms, but are limited in control of nocturnal acidity by their pharmacodynamic characteristics. This narrative review addresses the prevalence, impact and pharmacologic approaches used to control nocturnal acidity. Methods to optimize nocturnal acid control include careful attention to dosing schedule, using higher doses of PPIs, adding an histamine H2-receptor antagonist at bedtime to once or twice daily delayed-release PPI, or using immediate-release omeprazole (Zegerid powder for oral suspension; Santarus, Inc., San Diego, CA, USA). This new formulation appears to provide sustained control of intragastric pH at steady state, and when dosed at bedtime, and may be effective in improving control of nocturnal pH and treating night-time GERD.

Review of immediate-release omeprazole for the treatment of gastric acid-related disorders

Immediate-release omeprazole (Zegerid, Santarus) is the first immediate-release oral proton pump inhibitor to reach the market. As a powder formulation for oral suspension, it is indicated for the treatment of gastroesophageal reflux disease, erosive oesophagitis, duodenal ulcer and gastric ulcer, and is the only proton pump inhibitor approved for the reduction of risk of upper gastrointestinal bleeding in critically ill patients. Administration of immediate-release omeprazole at bedtime results in a rapid and sustained elevation of gastric pH, and seems to provide better night time control of gastric acidity than that observed with conventional morning dosing of delayed-release proton pump inhibitors. The immediate-release formulation may provide a good treatment option for patients who require flexible dosing, quick onset of action and nocturnal gastric acid control.

Comparison of the effects of immediate-release omeprazole powder for oral suspension and pantoprazole delayed-release tablets on nocturnal acid breakthrough in patients with symptomatic gastro-oesophageal reflux disease

BACKGROUND

Many patients treated with a proton-pump inhibitor for gastro-oesophageal reflux disease or erosive oesophagitis still have substantial night-time gastric acidity. A previous trial of a new immediate-release omeprazole oral suspension suggested that nocturnal gastric acidity could be more effectively controlled with a bedtime dose of immediate-release omeprazole than with a delayed-release proton-pump inhibitor administered before dinner or at bedtime.

AIM

To compare the ability of immediate-release omeprazole with pantoprazole to control nocturnal gastric acidity, when they were dosed once daily and twice daily.

METHODS

Thirty-six patients with nocturnal gastro-oesophageal reflux disease symptoms received immediate-release omeprazole and pantoprazole in this open-label, randomized-crossover trial. Median gastric pH, the percentage of time with gastric pH > 4 and the percentage of patients with nocturnal acid breakthrough, were evaluated with 24-h pH monitoring.

RESULTS

Repeated once daily (bedtime) dosing with immediate-release omeprazole suspension produced significantly better nocturnal gastric acid control than repeated once daily (predinner) or twice daily (prebreakfast and bedtime) dosing with pantoprazole delayed-release tablets (median pH: 4.7 vs. 2.0 and 1.7; percentage of time pH > 4: 55 vs. 27 and 34; nocturnal acid breakthrough: 53 vs. 78 and 75). Twice daily dosing (prebreakfast and bedtime) with immediate-release omeprazole 20 and 40 mg achieved the best night-time control of gastric acidity. Repeated once daily bedtime dosing with immediate-release omeprazole 40 mg and twice daily dosing with pantoprazole 40 mg gave similar 24-h pH control. No safety issues were associated with either drug in this trial.

CONCLUSIONS

Dosed once daily at bedtime, immediate-release omeprazole reduced nocturnal gastric acidity to a degree not observed with once daily dosing of delayed-release proton-pump inhibitors.

A comparative study of the early effects of tenatoprazole 40 mg and esomeprazole 40 mg on intragastric pH in healthy volunteers

BACKGROUND

Tenatoprazole is a novel proton pump inhibitor with a seven-hour plasma half-life.

AIM

To compare the effects of tenatoprazole 40 mg and esomeprazole 40 mg on intragastric acidity during the first 48 h in healthy volunteers.

METHODS

This randomized two-period crossover study included 24 Helicobacter Pylori-negative subjects; tenatoprazole 40 mg or esomeprazole 40 mg daily were given before breakfast for two consecutive days, with a 2-week wash-out between the administration periods. Intragastric pH was monitored for 48 h.

RESULTS

Over 48 h, tenatoprazole 40 mg exerted a more potent acid inhibition than esomeprazole 40 mg (median pH: 4.3 vs. 3.9, P < 0.08; per cent of time above pH 4: 57% vs. 49%, P < 0.03; proportion of subjects with at least half of the time above pH 4: 71% vs. 46%). These differences resulted from better night-time acid control with tenatoprazole 40 mg than esomeprazole 40 mg (first night median pH: 4.2 vs. 2.9, P < 0.0001; second night: 4.5 vs. 3.2, P < 0.0001). The duration of nocturnal acid breakthroughs was significantly reduced during both nights. In contrast, no significant difference was detected during the daytime periods between both regimens.

CONCLUSION

Over the first 48 h, tenatoprazole 40 mg achieves a better overall and night-time control of gastric pH than esomeprazole 40 mg. The translation of better early control of acidity into clinical benefits deserves further studies.

Clopidogrel versus aspirin and esomeprazole to prevent recurrent ulcer bleeding

BACKGROUND

Concurrent therapy with a proton-pump inhibitor is a standard treatment for patients receiving aspirin who are at risk for ulcer. Current U.S. guidelines also recommend clopidrogel for patients who have major gastrointestinal intolerance of aspirin. We compared clopidogrel with aspirin plus esomeprazole for the prevention of recurrent bleeding from ulcers in high-risk patients.

METHODS

We studied patients who took aspirin to prevent vascular diseases and who presented with ulcer bleeding. After the ulcers had healed, we randomly assigned patients who were negative for Helicobacter pylori to receive either 75 mg of clopidogrel daily plus esomeprazole placebo twice daily or 80 mg of aspirin daily plus 20 mg of esomeprazole twice daily for 12 months. The end point was recurrent ulcer bleeding.

RESULTS

We enrolled 320 patients (161 patients assigned to receive clopidogrel and 159 to receive aspirin plus esomeprazole). Recurrent ulcer bleeding occurred in 13 patients receiving clopidogrel and 1 receiving aspirin plus esomeprazole. The cumulative incidence of recurrent bleeding during the 12-month period was 8.6 percent (95 percent confidence interval, 4.1 to 13.1 percent) among patients who received clopidogrel and 0.7 percent (95 percent confidence interval, 0 to 2.0 percent) among those who received aspirin plus esomeprazole (difference, 7.9 percentage points; 95 percent confidence interval for the difference, 3.4 to 12.4; P=0.001).

CONCLUSIONS

Among patients with a history of aspirin-induced ulcer bleeding whose ulcers had healed before they received the study treatment, aspirin plus esomeprazole was superior to clopidogrel in the prevention of recurrent ulcer bleeding. Our finding does not support the current recommendation that patients with major gastrointestinal intolerance of aspirin be given clopidogrel.