Rabeprazole: an update of its use in acid-related disorders

Safety, Tolerability, and Pharmacokinetics of Anaprazole, a Novel Proton Pump Inhibitor, in Healthy Chinese Subjects

Anaprazole, a newly developed oral proton pump inhibitor, was evaluated for safety, tolerability, and pharmacokinetics in healthy Chinese subjects. This study involved administering either anaprazole sodium enteric-coated tablet or placebo, followed by monitoring the incidence and severity of any adverse events (AEs). The pharmacokinetic parameters of anaprazole, its isomer, and main metabolisms were determined. The results showed that both single-dose (2.5-120 mg) and multiple-dose (20 mg once daily, 40 mg once daily, or 20 mg twice daily) oral administration of anaprazole sodium enteric-coated tablet were safe and well tolerated. Following single-dose administration, the median time to reach maximum plasma concentration of anaprazole was between 3.50 and 5.25 hours, with mean elimination half-life of 1.22-3.79 hours. The absorption and elimination of anaprazole in the human body appeared to basically follow linear kinetics. After repeated dosing, steady-state concentrations of anaprazole, its isomer, and primary metabolites were achieved, with a median time to reach maximum plasma concentration of 3-3.75 hours and a mean elimination half-life of 1.61-2.27 hours for anaprazole. There was no significant drug accumulation after multiple-dose oral administration. In conclusion, anaprazole sodium enteric-coated tablets were found to be safe and well tolerated in healthy Chinese individuals. Anaprazole is absorbed and metabolized consistently in the human body without any accumulation.

Repurposing rabeprazole sodium as an anti-Clostridium perfringens drug by inhibiting perfringolysin O

AIMS

Clostridium perfringens infections affect food safety, human health, and the development of the poultry feed industry. Anti-virulence is an alternative strategy to develop new drug. Perfringolysin O (PFO) is an exotoxin of C. perfringens that has been demonstrated to play critical roles in the pathogenesis of this organism, promising it an attractive target to explore drugs to combat C. perfringens infection.

METHODS AND RESULTS

Based on an activity-based screening, we identified six PFO inhibitors from the Food and Drug Administration (FDA)-approved drug library, among which rabeprazole sodium (RS) showed an optimal inhibitory effect with an IC50 of 1.82 ± 0.746 µg ml-1. The GLY57, ASP58, SER190, SER193-194, ASN199, GLU204, ASN377, THR379, and ALA200 in PFO interacted with RS during binding based on an energy analysis and H-bond analysis. This interaction blocked the oligomer formation of PFO, thereby inhibiting its cytotoxicity. RS treatment significantly increased the survival rate and alleviated pathological damage in C. perfringens or PFO-treated Galleria mellonella.

CONCLUSIONS

RS could potentially be used as a candidate drug for treating C. perfringens infection.

Rabeprazole Promotes Vascular Repair and Resolution of Sepsis-Induced Inflammatory Lung Injury through HIF-1α

There are currently no effective treatments for sepsis and acute respiratory distress syndrome (ARDS). The repositioning of existing drugs is one possible effective strategy for the treatment of sepsis and ARDS. We previously showed that vascular repair and the resolution of sepsis-induced inflammatory lung injury is dependent upon endothelial HIF-1α/FoxM1 signaling. The aim of this study was to identify a candidate inducer of HIF-1α/FoxM1 signaling for the treatment of sepsis and ARDS. Employing high throughput screening of a library of 1200 FDA-approved drugs by using hypoxia response element (HRE)-driven luciferase reporter assays, we identified Rabeprazole (also known as Aciphex) as a top HIF-α activator. In cultured human lung microvascular endothelial cells, Rabeprazole induced HIF1A mRNA expression in a dose-dependent manner. A dose-response study of Rabeprazole in a mouse model of endotoxemia-induced inflammatory lung injury identified a dose that was well tolerated and enhanced vascular repair and the resolution of inflammatory lung injury. Rabeprazole treatment resulted in reductions in lung vascular leakage, edema, and neutrophil sequestration and proinflammatory cytokine expression during the repair phrase. We next used Hif1a/Tie2Cre knockout mice and Foxm1/Tie2Cre knockout mice to show that Rabeprazole promoted vascular repair through HIF-1α/FoxM1 signaling. In conclusion, Rabeprazole is a potent inducer of HIF-1α that promotes vascular repair and the resolution of sepsis-induced inflammatory lung injury via endothelial HIF-1α/FoxM1 signaling. This drug therefore represents a promising candidate for repurposing to effectively treat severe sepsis and ARDS.

Ilaprazole Compared With Rabeprazole in the Treatment of Duodenal Ulcer: A Randomized, Double-blind, Active-controlled, Multicenter Study

GOALS

The main goal of this study was to explore the dose-effect relationship of ilaprazole.

BACKGROUND

Ilaprazole is a kind of benzimidazole proton-pump inhibitor, which was confirmed efficacious and safe in treatment of duodenal ulcer (DU). However, the dose-effect relationship of ilaprazole was not clear.

STUDY

This was a double-blind, parallel, randomized study. Patients aged above 18 years with at least one endoscopically confirmed active nonmalignant DU were treated with rabeprazole 10 mg or ilaprazole 10 mg/5 mg for 4 weeks. Healing of ulcer was determined by its resolution from active to scarring stage. Symptoms relief was evaluated using a graded score. Safety and tolerability were evaluated on basis of clinical assessments.

RESULTS

A total of 390 patients completed the study finally. Ulcers were successfully healed in 75.38%, 77.86%, and 83.72% of patients after 4-week treatment with rabeprazole 10 mg, ilaprazole 5 mg, and ilaprazole 10 mg, respectively. The 4-week healing rate difference between rabeprazole 10 mg and ilaprazole 5 mg was 2.48% (95% confidence interval: -7.79% to 12.74%) leading to accept the noninferiority hypothesis. Logistic regression model suggested that ilaprazole 10 mg was superior to ilaprazole 5 mg at week 2 (odds ratio, 1.92; 95% confidence interval: 1.02, 3.59; P=0.04). Most patients (80%) became asymptomatic after treatment. At the dosages administered, the 3 drug groups exhibited similar efficacy and a similar safety profile.

CONCLUSIONS

Ilaprazole 5 mg is not inferior to rabeprazole 10 mg in treating DU, and a dose-effect relationship have been revealed between 5 mg and 10 mg of ilaprazole.

Inhibition of Gastric H+,K+-ATPase Activity in Vitro by Dissolution Media of Original Brand-Name and Generic Tablets of Lansoprazole, a Proton Pump Inhibitor

To investigate the inhibitory effect of a commercial proton pump inhibitor (lansoprazole) on the gastric proton pump H⁺,K⁺-ATPase in vitro, we used orally disintegrating (OD) tablets including original brand-name and generic tablets. In the course of the development of generic products, dissolution and clinical tests are necessary to ensure their bioequivalence to the original brand-name products; by contrast, there is almost no opportunity to demonstrate their activity in vitro. This study initially compared the similarity of the dissolution of test generic tablets with that of the original brand-name tablets. The dissolution tests for 15 and 30-mg lansoprazole tablets found their dissolution properties were similar. Subsequently, the dissolution media were sampled and then their effects on the H⁺,K⁺-ATPase activity were measured using tubulovesicles prepared from the gastric mucosa of hogs. We confirmed that the inhibitory effects of the generic tablets on H⁺,K⁺-ATPase activity were consistent with those of the original brand-name tablets. Furthermore, lansoprazole contents in each tablet estimated from their inhibitory effects were in good agreement with their active pharmaceutical ingredient content. To our knowledge, this is the first technical report to compare the in vitro biochemical activity of lansoprazole OD tablets between the original brand-name and generic commercial products.

Gut Microbiota Composition Before and After Use of Proton Pump Inhibitors

BACKGROUND

Recently, problems associated with proton pump inhibitor (PPI) use have begun to surface. PPIs influence the gut microbiota; therefore, PPI use may increase the risk of enteric infections and cause bacterial translocation. In this study, we investigated fecal microbiota composition, fecal organic acid concentrations and pH, and gut bacteria in the blood of the same patients before and after PPI use.

METHODS

Twenty patients with reflux esophagitis based on endoscopic examination received 8 weeks of treatment with PPIs. To analyze fecal microbiota composition and gut bacteria in blood and organic acid concentrations, 16S and 23S rRNA-targeted quantitative RT-PCR and high-performance liquid chromatography were conducted.

RESULTS

Lactobacillus species were significantly increased at both 4 and 8 weeks after PPI treatment compared with bacterial counts before treatment (P = 0.011 and P = 0.002, respectively). Among Lactobacillus spp., counts of the L. gasseri subgroup, L. fermentum, the L. reuteri subgroup, and the L. ruminis subgroup were significantly increased at 4 and 8 weeks after treatment compared with counts before treatment. Streptococcus species were also significantly increased at 4 and 8 weeks after PPI treatment compared with counts before treatment (P < 0.01 and P < 0.001, respectively). There was no significant difference in the total organic acid concentrations before and after PPI treatment. Detection rates of bacteria in blood before and after PPI treatment were 22 and 28%, respectively, with no significant differences.

CONCLUSIONS

Our quantitative RT-PCR results showed that gut dysbiosis was caused by PPI use, corroborating previous results obtained by metagenomic analysis.

Development and validation of dissolution testings in acidic media for rabeprazole sodium delayed-release capsules

Rabeprazole sodium (RAB) dissolved in acidic media is accompanied by its degradation in the course of dissolution testing. To develop and establish the accumulative release profiles of ACIPHEX^® Sprinkle (RAB) delayed-release capsules (ACIPHEX^® Sprinkle) in acidic media using USP apparatus 2 (paddle apparatus) as a dissolution tester, the issues of determination of accumulative release amount of RAB in these acidic media and interference of hydroxypropylmethyl cellulose phthalate were solved by adding appropriate hydrochloric acid (HCl) into dissolution samples coupled with centrifugation so as to remove the interference and form a solution of degradation products of RAB, which is of a considerably stable ultraviolet (UV) absorbance at the wavelength of 298 nm within 2.0 h. Therefore, the accumulative release amount of RAB in dissolution samples at each sample time points could be determined by UV-spectrophotometry, and the accumulative release profiles of ACIPHEX^® Sprinkle in the media of pH 1.0, pH 6.0, and pH 6.8 could be established. The method was validated per as the ICH Q2 (R1) guidelines and demonstrated to be adequate for quality control of ACIPHEX^® Sprinkle and the accumulative release profiles can be used as a tool to guide the formulation development and quality control of a generic drug for ACIPHEX^® Sprinkle.

Gastric Hypersecretory States: Investigation and Management

Hypersecretory conditions affecting the stomach account for significant morbidity and mortality manifested in some cases with peptic ulcer, gastrointestinal hemorrhage, and/or gastroesophageal reflux disease (GERD). The diagnosis of gastric acid hypersecretory states can be challenging and relies on the use of quantitative assays to measure gastric acid secretion and serum gastrin. The most common etiology for hypergastrinemia is the use of potent gastric acid inhibitors such as the proton pump inhibitors. The differential diagnosis of this condition is of critical importance, and will dictate management decisions. Conditions such as atrophic gastritis are relatively benign and can lead to hypergastrinemia without the presence of gastric acid hypersecretion. Zollinger-Ellison syndrome, on the other hand, causes hypergastrinemia with profound gastric acid hypersecretion [1]. More common causes of hypergastrinemia include gastric outlet obstruction, ileus, and chronic renal failure [2]. In most cases, proton pump inhibitors will be used to manage these conditions. In some instances, surgical therapy may be required. This chapter will review the important clinical causes of gastric acid hypersecretion and provide insights to the best medical management options to better care for patients with these disorders.

Furazolidone-based triple and quadruple eradication therapy for Helicobacter pylori infection

AIM: To evaluate the efficacy of furazolidone-based triple and quadruple therapy in eradicating Helicobacter pylori (H. pylori) in a multi-center randomized controlled trial.

METHODS: A total of 720 H. pylori positive patients with duodenal ulcer disease were enrolled at 10 different hospitals in Jiangxi province in China. The patients were randomly assigned to four treatment groups as follows: patients in Groups 1 and 3 received rabeprazole (10 mg), amoxicillin (1000 mg) and furazolidone (100 mg) twice daily for 7 and 10 d, respectively; patients in Groups 2 and 4 received rabeprazole (10 mg), bismuth (220 mg), amoxicillin (1000 mg) and furazolidone (100 mg) twice daily for 7 and 10 d, respectively. The primary outcome measure was H. pylori eradication rate 4 wk after treatment by intention-to-treat and per protocol analysis, while the secondary outcome measures were symptom and sign changes at the end of treatment and 4 wk after the end of treatment, as well as the proportion of patients who developed adverse events.

RESULTS: The demographic data of the four groups were not significantly different. Overall, 666 patients completed the scheme and were re-assessed with the ¹³C-urea breath test. The intention-to-treat analysis of the H. pylori eradication rates in Groups 1, 2, 3 and 4 were 74.44%, 82.78%, 78.89% and 86.11%, respectively. The H. pylori eradication rate in Group 4 was significantly higher than that in Group 1. According to the per protocol analysis, the H. pylori eradication rates in Groups 1, 2, 3 and 4 were 81.21%, 89.22%, 85.54% and 92.26%, respectively. The H. pylori eradication rate in Group 4 was significantly higher than that in Group 1. The number of adverse events was 15 (8.3%), 16 (8.9%), 15 (8.3%) and 17 (9.4%) in Groups 1, 2, 3 and 4, respectively, including dizziness, vomiting, diarrhea, nausea, skin rash, itchy skin, and malaise. The symptoms were relieved without special treatment in all of the patients.

CONCLUSION: Both 7- and 10-d quadruple furazolidone-based therapies achieve satisfactory H. pylori eradication rates.

Stability-indicating HPLC-DAD methods for determination of two binary mixtures: Rabeprazole sodium-mosapride citrate and rabeprazole sodium-itopride hydrochloride

Two selective stability-indicating HPLC methods are described for determination of rabeprazole sodium (RZ)–mosapride citrate (MR) and RZ–itopride hydrochloride (IO) mixtures in the presence of their ICH-stress formed degradation products. Separations were achieved on X-Bridge C18 column using two mobile phases: the first for RZ–MR mixture consisted of acetonitrile: 0.025 M KH₂PO₄ solution: TEA (30:69:1 v/v; pH 7.0); the second for RZ–IO mixture was at ratio of 25:74:1 (v/v; pH 9.25). The detection wavelength was 283 nm. The two methods were validated and validation acceptance criteria were met in all cases. Peak purity testing using contrast angle theory, relative absorbance and log A versus the wavelengths plots were presented. The % recoveries of the intact drugs were between 99.1% and 102.2% with RSD% values less than 1.6%. Application of the proposed HPLC methods indicated that the methods could be adopted to follow the stability of their formulations.

Effect of CYP2C19 genetic polymorphism on pharmacokinetics and pharmacodynamics of a new proton pump inhibitor, ilaprazole

It is well known that the CYP2C19 genetic polymorphism influences the pharmacokinetics and pharmacodynamics of proton pump inhibitors (PPIs), but no report has addressed the effects on ilaprazole, a newly developed PPI. To investigate the effects of the CYP2C19 genetic polymorphism on the disposition and pharmacodynamics of ilaprazole, multiple doses of once-daily 10 mg ilaprazole were repeatedly administered for 7 days to 27 healthy Korean participants, comprising 9 homozygous CYP2C19 extensive metabolizers (homo EMs), 10 heterozygous EMs (hetero EMs), and 8 homozygous poor metabolizers (PMs). The plasma concentration and pharmacodynamic response were measured in the last dose interval. Each genotype group was matched for gender and thus was composed of 4 male and 4 female participants when the analysis was conducted. The pharmacokinetic parameters estimated from the plasma concentrations of ilaprazole and its metabolite ilaprazole sulfone, the serum gastrin level, and the 24-hour intragastric pH were compared among the CYP2C19 genotype groups. No statistically significant differences in the maximum plasma concentration at steady state(C(ss,max)) and the area under the concentration-time curve from zero to 24 hours (AUC(τ)) of ilaprazole and ilaprazole sulfone were observed among the homo EM, hetero EM, and PM CYP2C19 genotypes. In addition, the mean 24-hour intragastric pH, the percentage of time at pH >4, and the AUC(τ) of serum gastrin showed no significant differences among the CYP2C19 genotype groups. The data suggests that the pharmacokinetics and pharmacodynamics of ilaprazole are not significantly influenced by the CYP2C19 genetic polymorphism in healthy participants.

Pancreatic islet cell carcinoma presenting with concurrent Cushing's and Zollinger-Ellison syndromes: case series and literature review

Cushing's syndrome and Zollinger-Ellison syndrome occur occasionally as a result of neuroendocrine cancers. The concurrence of the two syndromes has been considered to confer a poor clinical and therapeutic outcome. In this study, we are reviewing two patients with pancreatic islet cell carcinomas and with both Zollinger-Ellison and Cushing's syndromes, one followed up for more than 5 years, and the other still receiving therapy, 5 years since diagnosis. A literature review showed that surgery has limited utility as the majority of these patients had metastases at the time of diagnosis. Proton-pump inhibitors, ketoconazole, and somatostatin antagonists have a major role in controlling symptoms. Interferon and systemic chemotherapeutic agents play a role in the management of metastatic and fast-growing cases. Chemoembolization and bland embolization show encouraging results in controlling liver metastases. The latter was used effectively and more than once in the two patients presented herein. On the basis of recent molecular genetics studies, target therapy may be helpful, however, ongoing trials will define it's utility. As the data confers a worse prognosis versus other pancreatic neuroendocrine tumors, the relatively favorable outcome of the two patients reported herein may reflect the impact of multiple therapeutic modalities.

Rabeprazole: a review of its use in the management of gastric acid-related diseases in adults

Rabeprazole (Aciphex, Alfence, Pariet) is a proton pump inhibitor (PPI) used for the treatment of adults with conditions requiring a reduction of gastric acid secretion such as erosive or ulcerative gastro-oesophageal reflux disease (GORD), non-erosive reflux disease (NERD), duodenal and gastric ulcers, and pathological hypersecretory conditions including Zollinger-Ellison syndrome (ZES). It is also used as part of combination therapy for the eradication of Helicobacter pylori, a pathogen frequently implicated in the development of gastric and duodenal ulcers. Rabeprazole has a well established efficacy and safety profile in the treatment of gastric acid-related diseases. Rabeprazole is a useful, well tolerated and cost-effective option for the treatment of GORD, NERD, peptic ulcer and other gastric acid-related diseases (including ZES), and provides an appropriate alternative to other currently available PPIs, with the added benefits of having a consistent efficacy profile and low drug interaction potential due to its predominantly nonenzymatic metabolism.

Effect of MDR1 C3435T polymorphism on lansoprazole in healthy Japanese subjects

BACKGROUND AND AIMS

The effect of multidrug resistance transporter gene 1 (MDR1) on the bioavailability and kinetics of several substrates has not yet been fully elucidated. We evaluated the influence of MDR1 C3435T polymorphism on the pharmacokinetics and pharmacodynamics of lansoprazole in Japanese subjects.

METHODS

Fifteen healthy volunteers with the rapid extensive metabolizer genotype of CYP2C19 were classified into three MDR1 C3435T genotype groups: C/C (n = 5), C/T (n = 5), and T/T (n = 5). Lansoprazole 30 mg was administered orally for 15 days. The intragastric pH and plasma lansoprazole levels were determined on days 1 and 15.

RESULTS

On day 1, the mean C(max) of lansoprazole in the T/T group was significantly higher than that in the C/C or C/T groups (T/T 1,248, C/C 618, C/T 607 ng/ml; P = 0.038). On day 15, similar MDR1 genotype-dependent differences were observed in the C(max) of lansoprazole, although smaller than the differences observed on day 1. In contrast, the intragastric pH attained after lansoprazole administration did not differ among MDR1 genotype groups on either day 1 or day 15.

CONCLUSION

Although the sample size was small, our study demonstrated that the MDR1 C3435T polymorphism influenced the pharmacokinetics, but not the pharmacodynamics (i.e., intragastric pH), of lansoprazole in rapid metabolizers of CYP2C19.

Identification of degradation products in stressed tablets of Rabeprazole sodium by HPLC-hyphenated techniques

Three unknown impurities of Rabeprazole, a proton pump inhibitor, were formed in the formulated drug under the stress conditions, [40 degrees C/75% relative humidity (RH) for 6 months] with relative retention times (RRTs) 0.17, 0.22 and 0.28. The Impurity-I (0.17 RRT) was isolated using preparative HPLC and characterized by NMR and MS. The other two impurities, Impurity-II (RRT 0.22) and Impurity-III (RRT 0.28) could not be isolated, hence they are characterized by HPLC-hyphenated techniques, LC-NMR and high-resolution LC-MS. On the basis of the spectral data, the Impurity-I, Impurity-II and Impurity-III were characterized as 1-(1H-benzo[d]imidazol-2-yl)-3-methyl-4-oxo-1,4-dihydropyridine-2-carboxylic acid, 1H-benzo [d] imidazole-2-sulfonic acid and 4-(3-methoxy propoxy)-3-methyl-2-pyridine carboxylic acid, respectively.

Rabeprazole: a second-generation proton pump inhibitor in the treatment of acid-related disease

Rabeprazole is a proton pump inhibitor (PPI) presenting a very advantageous pharmacodynamic and pharmacokinetic profile over older PPIs. In particular, this drug has a very fast onset of action, due to a short activation time and a very high pKa, and may therefore be defined as a 'second generation' PPI. The aim of this article is to provide an update on the pharmacology and clinical profile of rabeprazole and its use in acid-related disorders, with a particular focus on its role in gastroesophageal reflux disease; in the treatment and prevention of duodenal and gastric ulcers and Zollinger-Ellison syndrome; in the therapy of the extraesophageal manifestations of gastroesophageal reflux disease (in particular the respiratory and ear, nose and throat ones); and in the eradication of Helicobacter pylori.

Medical treatment of gastrinomas

Gastrinomas are functional neuroendocrine tumors of the gastroenteropancreatic system. Surgery is first line treatment in gastrinomas, however often fails to be curative. This manuscript reviews current strategies of medical treatment of surgically non-curable gastrinoma. Symptomatic treatment with H(+)-K(+)-ATPase proton-pump inhibitors suppresses hypersecretion of gastric acid and substantially improves quality of life in patients with Zollinger-Ellison syndrome. Further medical therapy is only recommended in cases of progressive metastatic gastrinoma. In well differentiated neuroendocrine carcinoma (G1 and G2) a so-called biotherapy with somatostatin analogues exists as first-line and chemotherapy with streptocotozin plus doxorubicine/5-FU as second-line medical treatment option. In poorly differentiated neuroendocrine carcinoma (G3) chemotherapy with etoposide plus cisplatin is possible. Prospective future therapeutic strategies may include treatment with novel somatostatin analogues as well as angiogenesis inhibitors and kinase inhibitors targeting tumor-specific signaling cascades.

CYP2C19 pharmacogenomics associated with therapy of Helicobacter pylori infection and gastro-esophageal reflux diseases with a proton pump inhibitor

Proton pump inhibitors (PPIs), such as omeprazole, lansoprazole and rabeprazole, are metabolized by CYP2C19 in the liver. There are genetic differences in the activity of this enzyme. Genotypes of CYP2C19 are classified into three groups, rapid metabolizer (RM: *1/*1), intermediate metabolizer (IM: *1/*X) and poor metabolizer (PM: *X/*X) (*1 and 'X' represent the wild-type and mutant allele, respectively). The pharmacokinetics and pharmacodynamics of PPIs differ among three different CYP2C19 genotype groups. Plasma PPI levels and intragastric pHs during PPI treatment in the RM group are lowest, those in the IM group come next, and those in the PM group are highest of the three groups. These CYP2C19 genotypic differences in pharmacokinetics and pharmacodynamics of PPIs influence the healing and eradication rates for the gastro-esophageal reflux disease and Helicobacter pylori infection by PPI-based regimens. Recently, the CYP2C19 genotype-based tailored therapy for H. pylori infection has been found to be effective. CYP2C19 pharmacogenetics should be taken into consideration for the personalization of a PPI-based therapy.

Monitoring cytochrome P-450 activity during rabeprazole treatment in patients with gastresophageal reflux disease

Proton pump inhibitors (PPIs) are the cornerstone in the treatment of gastresophageal reflux disease (GORD). PPIs are metabolized by the hepatic cytochrome P-450 enzymes (CYP-450). Rabeprazole is a PPI whose metabolism shows fewer interactions compared to other PPIs. In this study we evaluated the influence of rabeprazole administration on hepatic CYP-450 activity as measured by the (13)C-aminopyrine breath test ((13)C-ABT) in a group of patients with GORD. (13)C-ABT was performed on five GORD patients both before and after 1 week of rabeprazole administration (20 mg, b.i.d.). Pretreatment (13)C-ABT results were compared to posttreatment results. Pre- and posttreatment (13)C-ABT results for patients were compared to those obtained in five controls who did the test twice, with a 1-week interval in between. Before treatment, the (13)C-ABT results for the GORD patients did not significantly differ from those of healthy subjects. After treatment, we observed no significant modification of the (13)C-ABT in GORD patients compared to pretreatment values ((13)C-ABT %dose/hr, 10.56+/-1.31 versus 11.17+/-0.88; (13)C-ABT %cumulative dose, 8.08+/-1.11 versus 8.34+/-0.56). Posttreatment (13)C-ABT results were not significantly different from those obtained in controls at weekly repetition of the test. In patients with GORD, 1-week, full-dose rabeprazole does not display any significant interactions with CYP-450 activity.

Development and validation of a dissolution test for rabeprazole sodium in coated tablets

The aim of this work is to develop and validate a dissolution test for rabeprazole sodium coated tablets using a reverse-phase liquid chromatographic method. After test sink conditions, dissolution medium and stability of the drug, the best conditions were: paddle at 75 rotations per minute (rpm) stirring speed, HCl 0.1 M and borate buffer pH 9.0 as dissolution medium for acidic and basic steps, respectively, volume of 900 ml for both. The quantitation method was also adapted and validated. Less than 10% of the label amount was released in the acid step, while more than 95% was achieved over 30 min in the basic one. The dissolution profile for tablets was considered satisfactory. The dissolution test developed was adequate for its purpose and could be applied for quality control of rabeprazole tablets, since there is no official monograph.

The role of proton pump inhibitors in the treatment of Zollinger-Ellison syndrome

Zollinger-Ellison syndrome is characterised by refractory peptic ulcer disease, diarrhoea and gastric acid hypersecretion associated with a gastrin-secreting tumour. The incidence is unknown, but, in the US, the frequency is 0.1-3.0 million people. Zollinger-Ellison syndrome is associated with multiple endocrine neoplasia type 1 in 25-35% of the cases. The diagnosis of Zollinger-Ellison syndrome is suggested when plasma gastrin is > 1000 pg/ml and the basal acid output is > 15 mEq/h or when associated with a pH < 2. The treatment is focused on controlling gastric acid hypersecretion and localisation of the tumour and its metastases. Proton pump inhibitors are the most effective antisecretory drugs and can be administered at high dosages. This review focuses on the role of the proton pump inhibitors in the management of gastric acid hypersecretion in Zollinger-Ellison syndrome.

Three-year oral pantoprazole administration is effective for patients with Zollinger-Ellison syndrome and other hypersecretory conditions

BACKGROUND

Zollinger-Ellison syndrome and idiopathic hypersecretion are gastrointestinal hypersecretory conditions requiring long-term maintenance.

AIMS

The safety and efficacy data for short-term (6-month) treatment of Zollinger-Ellison syndrome and idiopathic hypersecretion with oral pantoprazole were previously published. This study extends the initial observations to 3 years.

METHODS

The primary efficacy end point for this report was the control of gastric acid secretion in the last hour before the next dose of oral pantoprazole (acid output of <10 mmol/h; <5 mmol/h in subjects with prior acid-reducing surgery). Dose titration was permitted to a maximum of 240 mg per 24 h.

RESULTS

Twenty-four subjects completed the study. The acid output of 28 of 34 subjects was controlled at initial enrolment. The mean acid output rates were <10 mmol/h throughout the 36 months of treatment for 90-100% of the patients. The majority of the patients were controlled with b.d. doses of 40 or 80 mg pantoprazole at 36 months (acid output was controlled in 24 of 24 subjects). Pantoprazole was generally well tolerated with minimal adverse events reported.

CONCLUSIONS

Maintenance oral pantoprazole therapy up to 3 years at dosages of 40-120 mg b.d. was effective and well tolerated in patients with Zollinger-Ellison syndrome and other hypersecretory conditions.

Influence of CYP2C19 pharmacogenetic polymorphism on proton pump inhibitor-based therapies

Proton pump inhibitors (PPIs), such as omeprazole, lansoprazole, rabeprazole, esomeprazole, and pantoprazole, are mainly metabolized by CYP2C19 in the liver. There are genetically determined differences in the activity of this enzyme. The genotypes of CYP2C19 are classified into the three groups, rapid extensive metabolizer (RM), intermediate metabolizer (IM), and poor metabolizer (PM). The pharmacokinetics and pharmacodynamics of PPIs depend on CYP2C19 genotype status. Plasma PPI levels and intragastric pHs during PPI treatment in the RM group are lowest, those in the IM group come next, and those in the PM group are highest of the three groups. These CYP2C19 genotype-dependent differences in pharmacokinetics and pharmacodynamics of PPIs influence the cure rates for the gastro-esophageal reflux disease and H. pylori infection by PPI-based therapies. For the better PPI-based treatment, doses and dosing schemes of PPIs should be optimized based on CYP2C19 genotype status.

Low-dose rabeprazole, amoxicillin and metronidazole triple therapy for the treatment of Helicobacter pylori infection in Chinese patients

BACKGROUND

Rabeprazole in combination with amoxicillin and metronidazole (RAM) has been shown to be an effective second-line treatment of Helicobacter pylori infection. The effects were compared of 7-day low-dose and high dose rabeprazole in RAM for the primary treatment of H. pylori infection in Chinese patients.

METHODS

Helicobacter pylori-positive dyspeptic patients were randomized to receive either (i) rabeprazole 10 mg, amoxicillin 1000 mg and metronidazole 400 mg (RAM-10) or (ii) high-dose rabeprazole 20 mg, amoxicillin 1000 mg and metronidazole 400 mg (RAM-20), each given twice daily for 7 days. Helicobacter pylori eradication was confirmed by (13)c-urea breath test 5 weeks after stopping medications. side-effects of treatments were documented.

RESULTS

A total of 120 patients were eligible for analysis. By intention-to-treat and per-protocol analysis, the eradication rates were 83% and 86% in the RAM-10 group and 75% and 76% in the RAM-20 group, respectively (P = 0.26 and P = 0.17). Both regimens were well-tolerated and compliance was >98% in both groups.

CONCLUSIONS

Low-dose rabeprazole in combination with amoxicillin and metronidazole is an effective, economical and well-tolerated therapy for the treatment of H. pylori infection in Chinese population.

Bioequivalence evaluation of two rabeprazole enteric coated formulations in healthy Chinese volunteers

A bioequivalence study of two rabeprazole enteric-coated formulations was carried out in 20 healthy Chinese volunteers according to a single dose, two-sequence, crossover randomized design. The two formulations were administered in two treatment days, separated by a washout period of 7 days. Blood samples were collected at specified time intervals over 10 hours post-dosing. Plasma samples were separated and assayed for rabeprazole using a selective and sensitive HPLC method with UV detection. The pharmacokinetic parameters AUC(0-T), AUCmax, Cmax, tmax, t(1/2) and MRT were determined from plasma concentration-time profile of both formulations. ANOVA and two one-sided t test procedures showed no significant difference in log-transformed Cmax, AUC(0-T) AUC(0-infinity) while the 90% confidence interval (CI) of the ratio of the geometric means of their values were also used to assess bioequivalence between the two formulations. The results of this study indicated that the two rabeprazole formulations can be considered to be bioequivalent.

Potent Gastric Acid Inhibition in Helicobacter pylori Eradication

At present, antisecretory drugs--foremost among them the proton pump inhibitors (PPIs)--represent a keystone in Helicobacter pylori eradication therapy. The present article shall first compare the role of PPIs as compared with histamine H2 receptor antagonists, both of them in the role of antibiotic-associated antisecretory therapy, and shall then address the contribution of each of the various PPIs that have been developed until the present time to the H. pylori eradication therapies. In summary, it may be concluded that PPIs are more effective overall than H2 receptor antagonists when the two groups of antisecretory drugs are given at the usual standard doses together with antibiotics with the intention of eradicating H. pylori infection. However, all PPIs (omeprazole, lansoprazole, pantoprazole, rabeprazole, and esomeprazole) are equivalent when given together with two antibiotics to cure the infection.

A Pharmacological Approach to Gastric Acid Inhibition

Proton pump inhibitors have changed our approach to gastric acid-related diseases. They are much more potent acid inhibitors than H2-antagonists and exhibit a sophisticated mechanism of action. The present review analyses the general pharmacology of proton pump inhibitors and differentiates the specific characteristics of the various compounds that belong to this family. Special emphasis has been placed in describing the clinical implications of such differences and the potential importance for adverse effects.

Pharmacokinetic and pharmacodynamic evaluation of a novel proton pump inhibitor, YH1885, in healthy volunteers

To evaluate the pharmacokinetic and pharmacodynamic characteristics of YH1885, a novel proton pump inhibitor, a single-blind, randomized, placebo-controlled, dose-rising, parallel-group study was conducted in 46 healthy volunteers. The volunteers were randomly allocated to single dose groups of 60 mg, 100 mg, 150 mg, 200 mg, and 300 mg (6 subjects per dose, including 2 placebos) or to multiple-dose groups of 150 mg and 300 mg (once-daily dosing for 7 days; 8 subjects per dose, including 2 placebos). The multiple-dose study was conducted separately after the single-dose study. YH1885 was administered orally after overnight fasting. Serial blood samples, urine samples, and pharmacodynamic measurements were taken. Drug concentrations in plasma and urine were determined by liquid chromatography/mass spectrometry (LC/MS). Pharmacodynamic changes were evaluated by ambulatory intragastric pH monitoring and by serial measurements of serum gastrin concentrations. Assessments of safety and tolerability also were made. Plasma concentrations of YH1885 reached peak levels 1.3 to 2.5 hours after single-dose administration and then declined monoexponentially with a terminal half-life (t(1/2)) of 2.2 to 2.4 hours in dosage groups up to 200 mg in the single-dose study. YH1885 showed linear pharmacokinetic characteristics, and little accumulation occurred after multiple administrations. The parent drug was not detected in urine. Dose-related pharmacological effects were obvious for dose groups of 150 mg and higher in the single-dose study. The mean intragastric pH and the percentage of time at pH>4 were significantly increased. The onset of drug effect was rapid, and maximal effects were observed on the first day of administration during multiple dosing. Serum gastrin levels also showed rapid increases during dosing but with a weak dose-effect relationship. Neither serious nor dose-limiting adverse effects were observed. YH1885 was found to be safe and well tolerated and effectively inhibited acid secretion with dose-dependent increases in intragastric pH. The acid-suppressing efficacy of YH1885 needs to be further evaluated in patients with gastric acid-related diseases.

Pharmacogenomics of proton pump inhibitors

Proton pump inhibitors (PPIs), such as omeprazole, lansoprazole, rabeprazole, esomeprazole, and pantoprazole, are metabolized by cytochrome P450 isoenzyme 2C19 (CYP2C19) in the liver. There are genetic differences that affect the activity of this enzyme. The genotypes of CYP2C19 are classified into three groups: homozygous extensive metabolizer (homEM), heterozygous extensive metabolizer (hetEM), and poor metabolizer (PM). The pharmacokinetics and pharmacodynamics of PPIs differ among the different CYP2C19 genotype groups. Plasma PPI and intragastric pH levels during PPI treatment are the lowest in the homEM group and the highest in the PM group. These CYP2C19 genotype-dependent differences in pharmacokinetics and pharmacodynamics of PPIs are reflected in the cure rates for gastroesophageal reflux disease and Helicobacter pylori infection with PPI-based therapies. The CYP2C19 genotyping test is a useful tool for deciding on the optimal treatment regimen using a PPI, including a dual (PPI plus antibiotic) or a triple (PPI plus two antibiotics) therapy.

Progress with novel pharmacological strategies for gastro-oesophageal reflux disease

Gastro-oesophageal reflux disease (GORD) is a chronic disorder characterised by an increased exposure of the oesophagus to intragastric contents. Currently, GORD symptoms are maintained under control with antisecretory agents, mainly gastric proton pump inhibitors (PPIs). Although impaired oesophageal motility may partly underlie the pathophysiology of GORD, the use of prokinetic agents has been found to be unsatisfactory. To date, novel pharmacological approaches for GORD are mainly related to the control of transient lower oesophageal sphincter (LOS) relaxations (TLOSRs). The majority of patients with GORD have reflux episodes during TLOSRs, which are evoked by gastric distension, mainly occurring after ingestion of a meal. Patients with reflux disease with normal peristalsis and without or with mild erosive disease could potentially benefit from anti-TLOSR therapy. This therapy might also be of value to treat some severe forms of esophagitis in combination with PPIs. GABA-B-receptor agonists are the most promising class of agents identified so far for TLOSR control. The GABA-B-receptor agonist, baclofen, is the most effective compound in inhibiting TLOSRs in humans. Since baclofen has several CNS adverse effects, novel orally available GABA-B agonists are needed for effective and well tolerated treatment of GORD. Endogenous or exogenous cholecystokinin (CCK) causes a reduction in LOS pressure, an increase in TLOSR frequency and a reduction in gastric emptying. In healthy volunteers and patients with GORD, loxiglumide, a selective CCK1-receptor antagonist, was found to reduce the rate of TLOSRs, although its effect on postprandial acid reflux may be modest. Orally effective CCK antagonists are not marketed to date. The anticholinergic agent atropine, given to healthy volunteers and patients with GORD, markedly reduced the rate of TLOSRs. Because of severe gastrointestinal (and other) adverse effects of anticholinergics, including worsening of supine acid clearance and constipation, it is unlikely that this class of drugs will have a future as anti-TLOSR agents on a routine basis. In spite of their effectiveness in reducing TLOSR rate, untoward adverse effects, such as addiction and severe constipation, currently limit the use of morphine and other opioid mu-receptor agonists. The same applies to nitric oxide synthase inhibitors, which are associated with marked gastrointestinal, cardiovascular, urinary and respiratory adverse effects. Animal studies provide promising evidence for the use of cannabinoid receptor 1 agonists, by showing potent inhibition of TLOSRs in the dog, thus opening a new route for clinical investigation in humans. A better understanding of TLOSR pathophysiology is a necessary step for the further development of novel drugs effective for anti-reflux therapy.

Systematic review: Rabeprazole-based therapies in Helicobacter pylori eradication

AIM

To perform a systematic review of the efficacy of rabeprazole-based therapies in Helicobacter pylori eradication, and to conduct a meta-analysis comparing the efficacy of rabeprazole and other proton pump inhibitors when co-prescribed with antibiotics.

METHODS

Studies evaluating rabeprazole plus antibiotics were considered. Only randomized trials comparing rabeprazole and other proton pump inhibitors with antibiotics, and differing only in the proton pump inhibitor, were included in the meta-analysis. Electronic and manual bibliographic searches were conducted. The percentage (weighted mean) of successful eradication was calculated. Meta-analysis was performed by combining the odds ratios (OR) of the individual studies.

RESULTS

The eradication rates were as follows: 14-day rabeprazole-amoxicillin, 73%; rabeprazole-amoxicillin-clarithromycin for 3, 5, 7 and 10 days, 44%, 72%, 78% and 75%, respectively; low-dose rabeprazole (20 mg/day), amoxicillin and clarithromycin for 7 days, 81%; high-dose rabeprazole (40 mg/day), amoxicillin and clarithromycin for 7 days, 75%; 7-day rabeprazole-clarithromycin-nitroimidazole, 85%. Twelve comparative studies were included in the meta-analysis. The eradication rate with rabeprazole plus antibiotics was 79%; it was 77% with other proton pump inhibitors (OR = 1.15; 95% confidence interval, 0.93-1.42). Sub-analysis comparing rabeprazole at low doses (10 mg b.d.) with other proton pump inhibitors at standard doses (omeprazole 20 mg b.d. or lansoprazole 30 mg b.d.) showed no differences.

CONCLUSIONS

Rabeprazole achieves similar H. pylori eradication rates to omeprazole and lansoprazole when co-prescribed with antibiotics. Low doses of rabeprazole (10 mg b.d.), when administered with two antibiotics, may be sufficient to eradicate H. pylori infection.

Maintenance oral pantoprazole therapy is effective for patients with Zollinger-Ellison syndrome and idiopathic hypersecretion

OBJECTIVE

Maintenance proton pump inhibitor (PPI) therapy is effective for gastric acid hypersecretory states, although data with pantoprazole are limited. The aim of this study was to evaluate the safety and efficacy of long term p.o. pantoprazole in individuals with hypersecretion.

METHODS

All subjects had Zollinger-Ellison syndrome or idiopathic hypersecretion. Baseline acid output was measured in the presence of prior maintenance antisecretory therapy before pantoprazole exposure. The starting dose was 40 mg b.i.d. in most cases, and the dose was adjusted to document control within the first 2 wk of therapy. The maximal allowable dose was 240 mg daily. Acid output was measured on day 28 and then quarterly from month 3. The primary efficacy endpoint was documented control of acid secretion at 6 months, i.e., acid output in the last 1 h before the next dose of therapy of <10 mEq/h (<5 mEq/h in subjects with prior acid-reducing surgery).

RESULTS

A total of 26 subjects had Zollinger-Ellison syndrome (six with multiple endocrine neoplasia syndrome type 1) and nine had idiopathic hypersecretion. Pre-enrollment therapy included omeprazole in 27 subjects and lansoprazole in eight, and 82.4% of subjects were controlled on their prior regimens. With upward dose titration, acid output was controlled in all subjects by day 10 and in all but two (6%) at the 6-month time point. Median acid secretion on therapy at 6 months was <2 mEq/h (mean 2.2 mEq/h; range 0-10.5 mEq/h) at a dose of 40 mg b.i.d. for 24 subjects, 80 mg b.i.d. for seven subjects, and 120 mg b.i.d. for two subjects. During the course of the study, five subjects required doses of 240 mg daily. Pantoprazole was generally well tolerated. No cases of anterior optic ischemic neuropathy occurred. Five subjects died during follow-up, all because of events unrelated to the study drug.

CONCLUSIONS

Maintenance p.o. pantoprazole therapy at a dose of 80-240 mg/day in divided doses was both effective and generally well tolerated for patients with Zollinger-Ellison syndrome and idiopathic hypersecretion.

Optimal Treatment of Zollinger-Ellison Syndrome and Related Conditions in Elderly Patients

Zollinger-Ellison syndrome is characterised by refractory peptic ulcer disease, severe diarrhoea and gastric acid hypersecretion associated with an islet-cell tumour of the pancreas (gastrinoma). The true incidence and prevalence of this rare disease is unknown; in the US, the frequency is one per one million people and the age at presentation varies from 7 to 90 years. Zollinger-Ellison syndrome is sporadic in 62-80% of cases and in 20-38% of cases is associated with multiple endocrine neoplasia type 1 (MEN 1). The diagnosis of Zollinger-Ellison syndrome is certain when the plasma gastrin is >1000 pg/mL and the basal acid output is >15 mEq/h in patients with an intact stomach, >5 mEq/h in gastrectomised patients, or when this hypergastrinemia is associated with a pH <2. The treatment is based on control of gastric acid hypersecretion and of the malignant tumour and its possible metastases. Proton pump inhibitors are the most effective antisecretory drugs and can be administered in the elderly at high dosages without drug-related adverse effects. As an initial therapy, daily dosages of omeprazole 80-100 mg or pantoprazole 40-160 mg are employed. In long-term treatment the doses can be greatly reduced once effective control of the gastric output has been established. Intravenous proton pump inhibitors may be administered when patients cannot take oral therapy, particularly in acute conditions. All sporadic localised gastrinomas should be excised if possible. When liver metastases are also present, their debulking may improve symptoms and survival, and facilitate medical treatment. There is some controversy as to the surgical approach for gastrinomas associated with MEN 1. Somatostatin analogues can be useful in reducing gastric acid hypersecretion, serum gastrin and gastric enterochromaffin-like (ECL) cells and can thus contribute to treating the disease more effectively. Their antiproliferative effect can be used in treating liver metastases. Chemotherapy is not the therapy of choice in patients with gastrinomas and is indicated only in those with malignant progressive disease; interferon alpha, embolisation and chemoembolisation are not advisable for the elderly. The treatment of elderly Zollinger-Ellison syndrome patients, similarly to all elderly oncological patients, should be based on the use of comprehensive geriatric assessment. This will enable the clinician to define the functional status of the elderly person, to decide whether the patient can tolerate surgery and/or the stress of antineoplastic therapy, and finally, to determine whether this patient can tolerate an aggressive treatment for Zollinger-Ellison syndrome or whether the only possible choice is palliative relief of symptoms.

Esomeprazole: a review of its use in the management of acid-related disorders

Esomeprazole (S-isomer of omeprazole), the first single optical isomer proton pump inhibitor, generally provides better acid control than current racemic proton pump inhibitors and has a favourable pharmacokinetic profile relative to omeprazole. In a large well designed 8-week trial in patients (n >5000) with erosive oesophagitis, esomeprazole recipients achieved significantly higher rates of endoscopically confirmed healed oesophagitis than those receiving lansoprazole. Respective healed oesophagitis rates with once-daily esomeprazole 40mg or lansoprazole 30mg were 92.6 and 88.8%. Overall, esomeprazole was also better than omeprazole, although these differences were not always statistically significance. Ninety-two to 94% of esomeprazole recipients (40mg once daily) achieved healed oesophagitis versus 84 to 90% of omeprazole recipients (20mg once daily). Esomeprazole was effective across all baseline grades of oesophagitis; notably, relative to lansoprazole, as baseline severity of disease increased, the difference in rates of healed oesophagitis also increased in favour of esomeprazole. Resolution of heartburn was also significantly better with esomeprazole 40mg than with these racemic proton pump inhibitors. Long-term (up to 12 months) therapy with esomeprazole effectively maintained healing in these patients. Once-daily esomeprazole 20 or 40mg for 4 weeks resolved symptoms in patients with symptomatic gastro-oesophageal reflux disease (GORD) without oesophagitis. Symptoms were effectively managed in the long-term with symptom-driven on-demand esomeprazole (20 or 40mg once daily). Eradicating Helicobacter pylori infection is considered pivotal to successfully managing duodenal ulcer disease. Seven days' treatment (twice-daily esomeprazole 20mg plus amoxicillin 1g and clarithromycin 500mg) eradicated H. pylori in >/=86% of patients (intention-to-treat), a rate that was similar to equivalent omeprazole-based regimens. Esomeprazole is generally well tolerated, both as monotherapy and in combination with antimicrobial agents, with a tolerability profile similar to that of other proton pump inhibitors. Few patients discontinued therapy because of treatment-emergent adverse events (<3% of patients), with very few (<1%) drug-related serious adverse events reported.

CONCLUSIONS

Esomeprazole is an effective, well tolerated treatment for managing GORD and for eradicating H. pylori infection in patients with duodenal ulcer disease. In 8-week double-blind trials, esomeprazole healed oesophagitis and resolved symptoms in patients with endoscopically confirmed erosive oesophagitis and overall, provided better efficacy than omeprazole. Notably, in a large (n >5000 patients) double-blind trial, esomeprazole 40mg provided significantly better efficacy than lansoprazole in terms of healing rates and resolution of symptoms. Long-term therapy with esomeprazole maintained healed oesophagitis in these patients. Esomeprazole also proved beneficial in patients with symptomatic GORD without oesophagitis. Thus, esomeprazole has emerged as an option for first-line therapy in the management of acid-related disorders.

Esomeprazole: a review of its use in the management of acid-related disorders in the US

Esomeprazole, the S-isomer of omeprazole, is the first proton pump inhibitor to be developed as a single optical isomer. It provides better acid control than current racemic proton pump inhibitors and has a favourable pharmacokinetic profile relative to omeprazole. In large well designed 8-week trials in patients with erosive oesophagitis, esomeprazole recipients achieved significantly higher rates of endoscopically confirmed healed oesophagitis than those receiving omeprazole or lansoprazole. Esomeprazole was effective across all baseline grades of oesophagitis; notably, relative to lansoprazole, as the baseline severity of disease increased, the difference in rates of healed oesophagitis also increased in favour of esomeprazole. In two trials, 94% of patients receiving esomeprazole 40mg once daily achieved healed oesophagitis versus 84 to 87% of omeprazole recipients (20mg once daily). In a study in >5000 patients, respective healed oesophagitis rates with once-daily esomeprazole 40mg or lansoprazole 30mg were 92.6 and 88.8%. Resolution of heartburn was also significantly better with esomeprazole than with these racemic proton pump inhibitors. Long-term (up to 12 months) therapy with esomeprazole effectively maintained healed oesophagitis in these patients. Esomeprazole 20 or 40mg once daily for 4 weeks proved effective in patients with symptomatic gastro-oesophageal reflux disease (GORD) without oesophagitis. Eradicating Helicobacter pylori infection is considered pivotal to successfully managing duodenal ulcer disease. Ten days' triple therapy (esomeprazole 40mg once daily, plus twice-daily amoxicillin 1g and clarithromycin 500mg) eradicated H. pylori in 77 to 78% of patients (intention-to-treat) with endoscopically confirmed duodenal ulcer disease. Esomeprazole is generally well tolerated, both as monotherapy and in combination with antimicrobial agents. The tolerability profile is similar to that of other proton pump inhibitors. Few patients discontinued therapy because of treatment-emergent adverse events (<3% of patients) and very few (<1%) drug-related serious adverse events were reported.

CONCLUSIONS

Esomeprazole is an effective and well tolerated treatment for managing GORD and for eradicating H. pylori infection in patients with duodenal ulcer disease. In 8-week double-blind trials, esomeprazole effectively healed oesophagitis and resolved symptoms in patients with endoscopically confirmed erosive oesophagitis. Notably, in large (n >1900 patients) double-blind trials, esomeprazole provided significantly better efficacy than omeprazole or lansoprazole in terms of both healing rates and resolution of symptoms. Long-term therapy with esomeprazole effectively maintained healed oesophagitis in these patients. Esomeprazole was also effective in patients with symptomatic GORD. Thus, esomeprazole has emerged as an effective option for first-line therapy in the management of acid-related disorders.