Twice-daily dosing of esomeprazole effectively inhibits acid secretion in CYP2C19 rapid metabolisers compared with twice-daily omeprazole, rabeprazole or lansoprazole

Wake up to gastro-oesophageal reflux disease: The interplay between arousal and night-time reflux

This review examines the temporal association between nocturnal gastro-oesophageal reflux and sleep-arousal cycles. Most nocturnal gastro-oesophageal reflux events occur during the awake cycle, and arousals precede most nocturnal gastro-oesophageal reflux events, indicating that arousal from sleep predisposes to nocturnal gastro-oesophageal reflux. This sheds light on the complex relationship between nocturnal gastro-oesophageal reflux and sleep, and has implications for managing nocturnal gastro-oesophageal reflux symptoms. The appearance of symptoms and the pathophysiology of nocturnal gastro-oesophageal reflux are influenced by sleep hygiene, sleep disturbances and the misalignment of circadian rhythms. Nocturnal gastro-oesophageal reflux and its related sleep disorders are prevalent and negatively impact the quality of life. There is conflicting evidence on whether nocturnal gastro-oesophageal reflux and sleep disturbances are causally linked, and whether sleep disturbances drive nocturnal gastro-oesophageal reflux. Poor sleep quality increases oesophageal hypersensitivity and overall acid exposure. The nocturnal gastro-oesophageal reflux is linked to the more severe forms of gastro-oesophageal reflux disease, especially with atypical/extra-oesophageal manifestations and complications of mucosal damage such as oesophagitis and stricture, Barret's oesophagus, and oesophageal adenocarcinoma. This review highlights the role of sleep problems in presenting nocturnal gastro-oesophageal reflux, and the potential benefits of treating sleep disturbances in enhancing patient care and quality of life.

Prediction of Omeprazole Pharmacokinetics and its Inhibition on Gastric Acid Secretion in Humans Using Physiologically Based Pharmacokinetic-Pharmacodynamic Model Characterizing CYP2C19 Polymorphisms

PURPOSE

To develop a whole physiologically based pharmacokinetic-pharmacodynamic (PBPK-PD) model to describe the pharmacokinetics and anti-gastric acid secretion of omeprazole in CYP2C19 extensive metabolizers (EMs), intermediate metabolizers (IMs), poor metabolizers (PMs) and ultrarapid metabolizers (UMs) following oral or intravenous administration.

METHODS

A PBPK/PD model was built using Phoenix WinNolin software. Omeprazole was mainly metabolized by CYP2C19 and CYP3A4 and the CYP2C19 polymorphism was incorporated using in vitro data. We described the PD by using a turn-over model with parameter estimates from dogs and the effect of a meal on the acid secretion was also implemented. The model predictions were compared to 53 sets of clinical data.

RESULTS

Predictions of omeprazole plasma concentration (72.2%) and 24 h stomach pH after administration (85%) were within 0.5-2.0-fold of the observed values, indicating that the PBPK-PD model was successfully developed. Sensitivity analysis demonstrated that the contributions of the tested factors to the plasma concentration of omeprazole were Vmax,2C19 ≈ Papp > Vmax,3A4 > Kti, and contributions to its pharmacodynamic were Vmax,2C19 > kome > kms > Papp > Vmax,3A4. The simulations showed that while the initial omeprazole dose in UMs, EMs, and IMs increased 7.5-, 3- and 1.25-fold compared to those of PMs, the therapeutic effect was similar.

CONCLUSIONS

The successful establishment of this PBPK-PD model highlights that pharmacokinetic and pharmacodynamic profiles of drugs can be predicted using preclinical data. The PBPK-PD model also provided a feasible alternative to empirical guidance for the recommended doses of omeprazole.

A Pharmacogenetics-Based Approach to Managing Gastroesophageal Reflux Disease: Current Perspectives and Future Steps

Proton pump inhibitors (PPIs) are commonly used medications to treat acid-related conditions, including gastro-esophageal reflux disease (GERD). Gastroenterology guidelines mention the importance of CYP2C19 in PPI metabolism and the influence of CYP2C19 genetic variations on variable responses to PPIs, but do not currently recommend the genotyping of CYP2C19 prior to prescribing PPIs. There are strong data to support the influence of CYP2C19 genetic variations on the pharmacokinetics of PPIs and clinical outcomes. Existing pharmacogenetic guideline recommendations for dose increases focus on H. pylori and erosive esophagitis indications, but PPIs are also the main therapy for treating GERD. Recent data suggest GERD patients being treated with a PPI may also benefit from genotype-guided dosing. We summarize the literature supporting this contention and highlight future directions for improved management of patients with GERD through precision medicine approaches.

Helicobacter pylori infection

Helicobacter pylori infection causes chronic gastritis, which can progress to severe gastroduodenal pathologies, including peptic ulcer, gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. H. pylori is usually transmitted in childhood and persists for life if untreated. The infection affects around half of the population in the world but prevalence varies according to location and sanitation standards. H. pylori has unique properties to colonize gastric epithelium in an acidic environment. The pathophysiology of H. pylori infection is dependent on complex bacterial virulence mechanisms and their interaction with the host immune system and environmental factors, resulting in distinct gastritis phenotypes that determine possible progression to different gastroduodenal pathologies. The causative role of H. pylori infection in gastric cancer development presents the opportunity for preventive screen-and-treat strategies. Invasive, endoscopy-based and non-invasive methods, including breath, stool and serological tests, are used in the diagnosis of H. pylori infection. Their use depends on the specific individual patient history and local availability. H. pylori treatment consists of a strong acid suppressant in various combinations with antibiotics and/or bismuth. The dramatic increase in resistance to key antibiotics used in H. pylori eradication demands antibiotic susceptibility testing, surveillance of resistance and antibiotic stewardship.

Vonoprazan poses no additional risk of developing Clostridioides difficile infection compared to proton pump inhibitors

BACKGROUND AND AIM

The use of proton pump inhibitors (PPIs) has been repeatedly reported as a trigger of Clostridioides difficile infection (CDI), a leading cause of nosocomial diarrhea. However, only a few studies have reported on the association between vonoprazan, a novel potassium-competitive acid blocker providing potent acid suppression, and CDI, with no studies having been conducted in a clinical setting. We therefore evaluated the association between various classes of acid suppressants and CDI with special attention paid to differences in the magnitudes of association between PPIs and vonoprazan.

METHODS

A retrospective hospital-based cohort from a secondary-care hospital in Japan (n = 25 821) was collected, wherein eligible CDI cases were defined as hospital-onset cases (n = 91). A multivariable adjusted logistic regression analysis for the entire cohort and propensity analyses for subgroups consisting of PPI and/or vonoprazan users at various doses (n = 10 306) were performed.

RESULTS

The overall CDI incidence rate was 1.42/10 000 patient-days, which was comparable with previous reports. A multivariable analysis showed that both PPIs and vonoprazan were positively associated with CDI (odds ratios [95% confidence intervals]: 3.15 [1.67-5.96] and 2.63 [1.01-6.88], respectively). In addition, matched subgroup analyses showed that PPIs and vonoprazan had equivalent magnitudes of association with CDI.

CONCLUSIONS

We found that both PPIs and vonoprazan were associated with CDI, and the magnitude of the association was comparable. Because vonoprazan is widely available in Asian countries, further studies on the association of its usage with CDI are warranted.

Expert consensus on emergency procedures for portal hypertension bleeding (2022)

Expert consensus proposes an emergency treatment protocol for portal hypertension bleeding. Herein, the emergency treatment procedures, which include first aid, medical, interventional, and surgical treatments, are described. In addition, the indications, contraindications, operating norms, precautions, and prevention of complications of portal hypertension are described to optimize the first aid process.

Multidrug resistance in Helicobacter pylori infection

Helicobacter pylori (Hp), a well-known human pathogen, causes one of the most common chronic bacterial infections and plays an important role in the emergence of chronic progressive gastric inflammation and a variety of gastrointestinal diseases. The prevalence of Hp infection varies worldwide and is indirectly proportional to socio-economic status, especially during childhood. The response to the eradication therapy significantly depends on the antibiotic resistance specific to each geographical region; thus, currently, given the increasing prevalence of antimicrobial resistance (especially to clarithromycin, metronidazole, and levofloxacin), successful treatment for Hp eradication has become a real challenge and a critical issue. The most incriminated factors associated with multidrug resistance (MDR) in Hp proved to be the overuse or the improper use of antibiotics, poor medication adherence, and bacterial-related factors including efflux pumps, mutations, and biofilms. Up to 30% of first-line therapy fails due to poor patient compliance, high gastric acidity, or high bacteremia levels. Hence, it is of great importance to consider new eradication regimens such as vonoprazan-containing triple therapies, quintuple therapies, high-dose dual therapies, and standard triple therapies with probiotics, requiring further studies and thorough assessment. Strain susceptibility testing is also necessary for an optimal approach.

Night-time gastric acid suppression by tegoprazan compared to vonoprazan or esomeprazole

AIM

Nocturnal acid breakthrough has been considered an unmet need of proton pump inhibitors. Tegoprazan, a novel potassium-competitive acid blocker, is expected to show improved properties for this unmet need. This study was aimed to compare night-time acid suppression by tegoprazan with that by vonoprazan or esomeprazole, and to explore the effect of CYP2C19 phenotypes on acid-suppressive effects.

METHODS

A randomized, open-label, three-period, six-sequence crossover study was conducted. A single oral dose of tegoprazan 50 mg, vonoprazan 20 mg or esomeprazole 40 mg was administered at night in each period. Continuous intragastric pH was monitored at baseline and after each dosing.

RESULTS

16 healthy subjects (6 CYP2C19 extensive metabolizers, 5 intermediate metabolizers, 5 poor metabolizers) completed the study. After a single dose of tegoprazan, intragastric pH increased more rapidly to over 4 at approximately 1 hour compared to the other treatments, and elevated intragastric pH was maintained stably at night. Tegoprazan exhibited night-time acid suppression for slightly but not significantly longer than vonoprazan, and greater than esomeprazole; % Time pH ≥4 at night-time was 66.0%, 60.5% and 36.1% for tegoprazan, vonoprazan and esomeprazole, respectively. Night-time acid suppression by tegoprazan and vonoprazan was not dependent on CYP2C19 phenotypes, while that by esomeprazole tended to be influenced by CYP2C19 phenotypes.

CONCLUSIONS

Tegoprazan produced more rapid, potent and well sustained night-time acid suppression versus vonoprazan or esomeprazole when administered at night. Furthermore, tegoprazan showed no CYP2C19 phenotype dependency in acid suppression. It suggests the potential of tegoprazan, especially in preventing nocturnal acid breakthrough.

Pharmacokinetics of Esomeprazole in Critically Ill Patients

Background

Esomeprazole, a potent proton pump inhibitor (PPI), is widely used for the prevention of stress ulcers in intensive care unit (ICU) patients.

Objective

This study investigates the pharmacokinetics (PK) of esomeprazole in critically ill patients.

Methods

The study included eligible adult ICU patients who received endotracheal intubation assisted mechanical ventilation for more than 48 h and had at least an extra risk factor for stress ulcers. All enrolled patients received once-daily intravenous (IV) esomeprazole 40 mg. After the first dose of esomeprazole was administrated, serial blood samples were collected at 3, 5, 15, 30 min and 1, 2, 4, 6, 8, and 10 h. The total sample concentrations of esomeprazole were measured by UPLC-MS/MS. Esomeprazole PK parameters were analyzed using noncompartmental analysis.

Results

A total of 30 patients were evaluable. Mean age and body mass index (BMI) were 61.97 years and 23.14. PK sampling on the first dose resulted in the following median (IQR) parameters: AUC_0−∞ 8.06 (6.65–9.47) mg·h/L; MRT_0−∞ 4.70 (3.89–5.51) h; t_1/2 3.29 (2.7–3.87) h; V 24.89 (22.09–27.69) L; CL 6.13 (5.01–7.26) L/h; and C_max 2.56 (2.30–2.82) mg/L.

Conclusions

According to the label of esomeprazole, our study showed different esomeprazole PK parameters in ICU patients compared with healthy volunteers. Esomeprazole has unique pharmacokinetic parameters in critically ill patients.

Influence of Cytochrome P450 2C19 Genotype on Helicobacter pylori Proton Pump Inhibitor-Amoxicillin-Clarithromycin Eradication Therapy: A Meta-Analysis

Background: Proton pump inhibitors (PPIs) are the first-line treatment for acid-related diseases. The pharmacokinetics and therapeutic efficacy of PPIs, however, are influenced by genetic factors such as variants in genes encoding drug-metabolizing enzymes (e.g., cytochrome P450 2C19 [CYP2C19]) and drug transporters. We performed a meta-analysis to evaluate the influence of CYP2C19 genotype and PPI class, PPI dose, treatment duration and clarithromycin dose on the cure rate of PPI-containing Helicobacter pylori eradication therapy.

Methods: Randomized control trials (RCTs) investigating cure rates using a PPI-amoxicillin-clarithromycin regimen among different CYP2C19 genotypes through May 2021 were included.

Results: A total of 25 studies (5,318 patients) were included. The overall eradication rate in the intention-to-treat analysis was 79.0% (3,689/4,669, 95% confidence interval [CI]: 77.8–80.2%), and that in CYP2C19 extensive metabolizers (EMs), intermediate metabolizer (IMs) and poor metabolizers (PMs) was 77.7% (1,137/1,464, 95% CI: 75.3–79.6%), 81.2% (1,498/1,844, 95% CI: 79.3–83.0%) and 86.8% (644/742, 95% CI: 83.9–88.9%), respectively. Meta-analysis showed that the relaTakashitive risk of failed eradication in CYP2C19 EMs compared with IMs and PMs was 1.21 (95% CI: 1.06–1.39, P = 0.006) and 1.57 (95% CI: 1.27–1.94, P < 0.001), respectively, in the fixed-effects model. The cure rate of omeprazole and lansoprazole-containing eradication regimens differed among CYP2C19 genotypes (P < 0.05), while that of rabeprazole and esomeprazole-containing regimens was similar.

Conclusion: The cure rates of PPI-amoxicillin-clarithromycin H. pylori eradication regimen, especially those containing omeprazole and lansoprazole, differ among CYP2C19 genotypes. Therefore, selection of a second-generation PPI or tailored treatment may achieve higher eradication rates than first-generation PPI-amoxicillin-clarithromycin triple regimen.

Prevention of delayed bleeding with vonoprazan in upper gastrointestinal endoscopic treatment

BACKGROUND

Delayed bleeding is the major adverse event in upper gastrointestinal endoscopic treatment (UGET). We aimed to investigate the efficacy of vonoprazan, which is the novel strong antisecretory agent, to reduce the risk for delayed bleeding in comparison with proton pump inhibitors (PPIs) in UGET.

METHODS

This retrospective population-based cohort study used the Diagnosis Procedure Combination database in Japan. We included patients on vonoprazan or PPI in UGET between 2014 and 2019. The primary outcome was delayed bleeding. We conducted propensity score matching to balance the comparison groups, and logistic regression analyses to compare the bleeding outcomes.

RESULTS

We enrolled 124,422 patients, in which 34,822 and 89,600 were prescribed with vonoprazan and PPI, respectively. After propensity score matching, the risk for delayed bleeding was lower in vonoprazan than in PPI (odds ratio [OR], 0.75; 95% confidence interval [CI], 0.71-0.80), consistent with sensitivity analysis results. In the subgroup analyses of seven UGET procedures, vonoprazan was significantly advantageous in esophageal endoscopic submucosal dissection (E-ESD) (OR, 0.71; 95% CI, 0.54-0.94) and gastroduodenal endoscopic submucosal dissection (GD-ESD) (OR, 0.70; 95% CI, 0.65-0.75), although correction for multiple testing of the outcome data removed the significance in E-ESD. These results were also consistent with sensitivity analysis results. In the five other procedures, no significant advantage was found.

CONCLUSIONS

This nationwide study found that, compared with PPI, vonoprazan can reduce delayed bleeding with approximately 30% in GD-ESD. Vonoprazan has the possibility to become a new treatment method for preventing delayed bleeding in this procedure.

Eradication Rates for Esomeprazole and Lansoprazole-Based 7-Day Non-Bismuth Concomitant Quadruple Therapy for First-Line Anti-Helicobacter pylori Treatment in Real World Clinical Practice

PURPOSE

Non-bismuth concomitant quadruple therapy is commonly administered in Taiwan, achieving an acceptable efficacy as a first-line anti-Helicobacter pylori treatment. This study compared the eradication rates between esomeprazole- and lansoprazole-based non-bismuth concomitant quadruple therapy for first-line anti-H. pylori treatment.

PATIENTS AND METHODS

This study included 206 H. pylori-infected naïve patients between July 2016 and February 2019. The patients were prescribed with either a 7-day non-bismuth containing quadruple therapy (esomeprazole, 40 mg twice daily; amoxicillin, 1 g twice daily; and metronidazole, 500 mg twice daily; and clarithromycin, 500 mg twice daily for 7 days [EACM group]; lansoprazole, 30 mg twice daily; amoxicillin, 1 g twice daily; metronidazole, 500 mg twice daily; and clarithromycin, 500 mg twice daily [LACM group]). Then, the patients were asked to perform urea breath tests 8 weeks later.

RESULTS

The eradication rates in the EACM group were 86.1% (95% confidence interval [CI], 77.8%-92.2%) and 90.6% (95% CI, 82.9%-95.6%) in the intention-to-treat (ITT) and the per-protocol (PP) analyses, respectively. Moreover, the eradication rates in the LACM group were 90.1% (95% CI, 82.6%-95.2%) and 92.6% (95% CI, 85.5%-96.9%) in the ITT and the PP analyses, respectively. Consequently, the LACM group exhibited more diarrhea patients than the EACM group (7.1% versus 1.0%, p = 0.029), but all symptoms were mild. Univariate analysis in this study showed that metronidazole-resistant strains were the clinical factor affecting the eradications (95.3% versus 78.9%, p = 0.044). Moreover, a trend was observed in dual clarithromycin- and metronidazole-resistant strains (91.5% versus 66.7%, p = 0.155).

CONCLUSION

The eradication rates between esomeprazole and lansoprazole-based non-bismuth concomitant quadruple therapy for first-line H. pylori treatment were similar in this study. Both could achieve a > 90% report card in the PP analysis.

The appropriate cutoff gastric pH value for Helicobacter pylori eradication with bismuth-based quadruple therapy

BACKGROUND

This study aimed to investigate whether an increased proton pump inhibitor (PPI) dose enhanced the efficacy of Helicobacter pylori (H. pylori) eradication and determine the appropriate cutoff intragastric pH value that could predict H. pylori eradication with bismuth-based quadruple therapy.

MATERIALS AND METHODS

A total of 207 H. pylori infected, treatment naive patients were enrolled in this prospective, open-label, randomized controlled trial. Patients were randomly allocated into Eso40-group (esomeprazole 40 mg bid) and Eso20-group (esomeprazole 20 mg bid), and their CYP2C19 genotyping status was assessed. The 24-h intragastric pH monitoring on day 7 was performed, and percentage of time gastric pH ≥ 3, ≥4, ≥5, and ≥6 (pH holding time ratios; HTRs) were measured. H. pylori eradication was evaluated using ¹³ C-urea breath test.

RESULTS

No significant difference in the eradication rates was observed between two groups. The median 24-h intragastric pH value was not significant different between two groups but the Eso40 Group had a significant higher pH4 HTRs (91.11% [95%CI: 87.50%-95.83%] vs. 95.83% [95.83%-100%]; p = .002). Additionally, the median 24-h intragastric pH value showed significantly difference between two groups in EM genotype (Eso20 Group 6.00 [95%CI; 5.75-6.15] vs. Eso40 Group 6.30 [6.05-6.30]; p = .019). Similar results were observed in pH4 HTRs. There were significant differences in intragastric pH value (6.10 [95%CI: 4.40-7.00] vs. 5.65 [4.85-5.95], p = .038) and in pH4 HTRs (96% [95%CI: 92.00%-96.00%] vs. 87.5% [67.00%-100.0%], p = .019) between eradication-successful and eradication-failed patients. Statistical analysis suggested that the median intragastric pH = 5.7 could identify the success of H. pylori eradication.

CONCLUSIONS

Bismuth-based quadruple therapy resulted in high H. pylori eradication rates either in PPI standard or double doses. Double dose of esomeprazole is associated with better intragastric acid suppression. A median 24-h intragastric pH of 5.7 could be appropriate cutoff value for predicting the successful H. pylori eradication.

Effect of Antibiotic Susceptibility and CYP3A4/5 and CYP2C19 Genotype on the Outcome of Vonoprazan-Containing Helicobacter pylori Eradication Therapy

Background: Helicobacter pylori eradication containing the potassium-competitive acid blocker, vonoprazan, achieves a higher eradication rate than therapy with proton pump inhibitors (PPIs). Because vonoprazan is mainly metabolized by CYP3A4/5, CYP genotype may affect the eradication rate. We investigated the influence of antibiotic susceptibility and CYP3A4/5 and CYP2C19 genotypes on the eradication rates. Methods: A total of 307 Japanese who were genotyped for CYP3A4 *1/*22, CYP3A5 *1/*3 and CYP2C19 *1/*2/*3/*17, and investigated for susceptibility to antimicrobial agents, received vonoprazan-containing regimens: (1) With amoxicillin and clarithromycin as the first-line treatment; (2) with amoxicillin and metronidazole as the second-line treatment; or (3) with amoxicillin and sitafloxacin as the third-line treatment. Results: The eradication rate was 84.5% (95% confidence interval [CI]: 78.9–89.1%) using first-line, 92.6% (95% CI: 82.1–97.9%) using second-line and 87.5% (95% CI: 73.1–95.8%) using third-line treatment. Infection with clarithromycin-resistant strains was a predictive factor for failed eradication (odds ratio: 5.788, 95% CI: 1.916–17.485, p = 0.002) in multivariate analysis. No significant differences were observed in the eradication rate of regimens among CYP3A4, CYP3A5 and CYP2C19 genotypes. Conclusions: Genotyping for CYP3A4 *1/*22, CYP3A5 *1/*3 and CYP2C19 *1/*2/*3/*17 before vonoprazan-containing eradication treatment may not be useful for predicting clinical outcomes.

Nocturnal Gastroesophageal Reflux Disease (GERD) and Sleep: An Important Relationship That Is Commonly Overlooked

Gastroesophageal reflux disease (GERD) is a prevalent, chronic medical condition that affects 13% of the adult population globally at least once a week. Sleep disturbances are frequently encountered in up to 25% of the GERD patients, likely due to nocturnal gastroesophageal reflux (GER). With advance in diagnostic techniques allowing for an improved understanding of involved physiological mechanisms of nocturnal reflux, there is growing evidence of a bidirectional relationship between GERD and sleep disturbances. Furthermore, nocturnal GER is associated with more complicated GERD. Obstructive sleep apnea (OSA) and GERD also have been linked, but to what degree remains controversial. Treatment of nocturnal GER has been shown to improve both subjective and objective sleep measures. The therapeutic approach includes lifestyle modifications and medication individualization and optimization with proton-pump inhibitors serving as the mainstay of treatment. Antireflux surgery and newer endoscopic procedures have been demonstrated to control nocturnal GER.

Previous Helicobacter pylori infection-induced atrophic gastritis: A distinct disease entity in an understudied population without a history of eradication

Individuals with chronic atrophic gastritis who are negative for active H. pylori infection with no history of eradication therapy have been identified in clinical practice. By excluding false-negative and autoimmune gastritis cases, it can be surmised that most of these patients have experienced unintentional eradication of H. pylori after antibiotic treatment for other infectious disease, unreported successful eradication, or H. pylori that spontaneously disappeared. These patients are considered to have previous H. pylori infection-induced atrophic gastritis. In this work, we define these cases based on the following criteria: absence of previous H. pylori eradication; atrophic changes on endoscopy or histologic confirmation of glandular atrophy; negative for a current H. pylori infection diagnosed in the absence of proton-pump inhibitors or antibiotics; and absence of localized corpus atrophy, positivity for autoantibodies, or characteristic histologic findings suggestive of autoimmune gastritis. The risk of developing gastric cancer depends on the atrophic grade. The reported rate of developing gastric cancer is 0.31%-0.62% per year for successfully eradicated severely atrophic cases (pathophysiologically equal to unintentionally eradicated cases and unreported eradicated cases), and 0.53%-0.87% per year for spontaneously resolved cases due to severe atrophy. Therefore, for previous H. pylori infection-induced atrophic gastritis cases, we recommend endoscopic surveillance every 3 years for high-risk patients, including those with endoscopically severe atrophy or intestinal metaplasia. Because of the difficulty involved in the endoscopic diagnosis of gastric cancer in cases of previous infection, appropriate monitoring of the high-risk subgroup of this understudied population is especially important.

High-dose PPI-amoxicillin dual therapy with or without bismuth for first-line Helicobacter pylori therapy: A randomized trial

BACKGROUND

A reliably highly effective high-dose proton-pump inhibitor plus amoxicillin (dual Helicobacter pylori therapy) has remained elusive. We compared whether the addition of bismuth to high-dose dual therapy would improve the efficacy of high-dose dual therapy as first-line treatment.

METHODS

This was an open-label, randomized single-center study of 160 treatment-naive patients with H. pylori infection who were randomly assigned to 14-day therapy with esomeprazole 40 mg twice a day plus amoxicillin 1 g three times a day with or without bismuth potassium citrate 600 mg (elemental bismuth 220 mg) twice a day. Antibiotic resistance was determined by agar dilution method and eradication by ¹³ C-urea breath test.

RESULTS

The per-protocol eradication rates were 96.1%; 95% CI = 88.9%-99.2% (73/76) without bismuth vs 93.3%; 95% CI = 85.1%-97.8% (70/75) with bismuth (P = 0.494). The intention-to-treat eradication rates were 92.5%; 95% CI = 84.4%-97.2% (74/80) without bismuth and 88.8%; 95% CI = 79.7%-94.7% (71/80) with bismuth (P = 0.416). Resistance to amoxicillin, clarithromycin, metronidazole, and levofloxacin was 0%, 31.7%, 81.4%, and 40.7%, respectively. Smoking reduced treatment effectiveness limited to those not receiving bismuth. The per-protocol eradication rates were 70% (7/10) vs 100% (66/66) in smokers vs non-smokers without bismuth (P = 0.002), and 100% (10/10) in smokers vs 92.3% (60/65) in non-smokers with bismuth (P = 1.0). The adverse event rates were 7.5% (6/80) without bismuth vs 11.3% (9/80) with bismuth (P = 0.416).

CONCLUSIONS

Fourteen-day high-dose dual therapy was both effective and safe for first-line treatment in a region of high prevalence antibiotic resistance. Adding bismuth only improved treatment effectiveness among smokers.

Association of proton pump inhibitors with risk of hepatic encephalopathy in advanced liver disease: A meta-analysis

BACKGROUND

Several studies have explored the association between the use of proton pump inhibitors (PPIs) and the risk of developing hepatic encephalopathy (HE) in patients with advanced liver disease. However, the evidence-based conclusions are controversial. We hypothesized that using PPIs may increase the risk of HE in patients with advanced liver disease. If confirmed, clinicians must strictly adhere to the indications for PPI treatment in this population.

AIM

To evaluate the pooled risk of HE in patients with advanced liver disease who use PPIs.

METHODS

Three electronic databases (PubMed, EMBASE, and the Cochrane Library) were searched from the date of database inception through January 8, 2019 to identify comparative studies evaluating the association between PPI use and the risk of HE. Data from the included studies were extracted. The random-effects model was used for pooling risk estimates and the corresponding 95% confidence intervals (CIs). Subgroup and sensitivity analyses were also performed.

RESULTS

In total, 4342 patients from five case-control studies and 188053 patients from four cohort studies were included in this analysis. In patients with advanced liver disease, PPI use was associated with an elevated risk of developing HE, with significant heterogeneity. The pooled odds ratio for case-control studies was 2.58 (95%CI: 1.68-3.94, I² = 72%). The pooled RR for cohort studies was 1.67 (95%CI: 1.30-2.14, I² = 67%). The results of the subgroup analyses suggested that the heterogeneity may be the result of differences in the study designs and the definitions of PPI use. The sensitivity and subgroup analyses did not alter our findings.

CONCLUSION

In patients with advanced liver disease, PPI use is associated with an elevated risk of HE. Future large prospective studies are needed to confirm this association.

Hypergastrinemia in Long-Term Use of Proton Pump Inhibitors

BACKGROUND/AIM

The use of proton pump inhibitors (PPIs) is known to lead to hypergastrinemia; however, the data in patients with atrophic gastritis is still lacking. The aim of this study was to investigate the effects of long-term PPIs use on the gastrin levels in patients with atrophic gastritis and to determine factors affecting hypergastrinemia in long-term users of PPIs.

METHODS

Serum Helicobacter pylori IgG, gastrin and pepsinogen levels were measured. Atrophic gastritis was assessed by upper gastrointestinal endoscopies based on the Kimura-Takemoto classification and pepsinogen levels. CYP2C19 polymorphisms were assessed using DNA extracted from peripheral blood.

RESULTS

A total number of 382 patients (275 men and 107 women) were enrolled. Median serum gastrin levels were higher in PPI users than in non- users (234 vs. 113 pg/mL, p < 0.001) and in women than in men (252 vs. 155 pg/mL, p = 0.006). Gastrin levels were significantly associated with corpus atrophy only in the subgroup of non-users of PPIs. Multivariate analysis revealed that hypergastrinemia (over 150 pg/mL) was significantly associated with PPI use (OR 5.30; 95% CI 3.32-8.47), women (OR 2.22; 95% CI 1.33-3.72) and corpus atrophy (OR 1.82; 95% CI 1.14-2.90).

CONCLUSION

PPI use, women and corpus atrophy were risk factors for hypergastrinemia. Gender, but not corpus atrophy, affected the gastrin levels in long-term users of PPIs.

Proton pump inhibitors: from CYP2C19 pharmacogenetics to precision medicine

Introduction: Proton Pump inhibitors (PPIs) are commonly used for a variety of acid related disorders. Despite the overall effectiveness and safety profile of PPIs, some patients do not respond adequately or develop treatment related adverse events. This variable response among patients is in part due to genotype variability of CYP2C19, the gene encoding the CYP450 (CYP2C19) isoenzyme responsible for PPIs metabolism.

Areas covered: This article provides an overview of the pharmacokinetics and mechanism of action of the currently available PPIs, including the magnitude of CYPC19 contribution to their metabolism. Additionally, the role of CYP2C19 genetic variability in the therapeutic effectiveness or outcomes of PPI therapy is highlighted in details, to provide supporting evidence for the potential value of CYP2C19 genotype-guided approaches to PPI drug therapy.

Expert opinion: There is a large body of evidence describing the impact of CYP2C19 variability on PPIs and its potential role in individualizing PPI therapy, yet, CYP2C19 pharmacogenetics has not been widely implemented into clinical practice. More data are needed but CYP2C19 genotype-guided dosing of PPIs is likely to become increasingly common and is expected to improve clinical outcomes, and minimize side effects related to PPIs.

Fifth Chinese National Consensus Report on the management of Helicobacter pylori infection

BACKGROUND

Since the 'Fourth Chinese National Consensus Report on the management of H. pylori infection' was published in 2012, three important consensuses (Kyoto global consensus report on H. pylori gastritis, The Toronto Consensus for the Treatment of H. pylori Infection in Adults and Management of H. pylori infection-the Maastricht V/Florence Consensus Report) have been published regarding the management of H. pylori infection.

MATERIALS AND METHODS

A Delphi method was adopted to develop the consensus of relevant 'statements'. First, the established 'statements' were sent to experts via email. Second, after undergoing two rounds of consultation, the initial statements were discussed face to face and revised in the conference item by item on 16 December 2016. Finally, 21 core members of conferees participated in the final vote of statements. Voting for each statement was performed using an electronic system with levels of agreements shown on the screen in real time.

RESULTS

Consensus contents contained a total of 48 "statements" and related 6 parts, including indications for H. pylori eradication, diagnosis, treatment, H. pylori and gastric cancer, H. pylori infection in special populations, H. pylori and gastrointestinal microbiota.

CONCLUSIONS

Recommendations are provided on the basis of the best available evidence.

Refractory gastroesophageal reflux disease: Current status and perspectives

Patients with gastroesophageal reflux disease (GERD) who do not respond to an 8-12 wk course of acid-suppressive therapy with a proton pump inhibitor twice daily, with symptoms such as heartburn and acid reflux symptoms persisting after therapy, can be diagnosed with refractory GERD (RGERD). It is estimated that RGERD accounts for approximately 10%-40% of all GERD cases. Due to complicated causes, the clinical recognition of RGERD is insufficient. Thanks to the advances in the basic and clinical research of RGERD in recent years, there have been updated consensus guidelines on the diagnosis and treatment of RGERD in America and Asia (including China). This paper reviews the definition, epidemiology, pathophysiology, diagnostic evaluation, and treatment of RGERD.

A review of medical therapy for proton pump inhibitor nonresponsive gastroesophageal reflux disease

Up to 40% of patients report persistent gastroesophageal reflux disease (GERD) symptoms despite proton pump inhibitor (PPI) therapy. This review outlines the evidence for medical therapy for PPI nonresponsive GERD. A literature search for GERD therapies from 2005 to 2015 in PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews identified 2928 unique citations. Of those, 40 unique articles specific to the impact of PPI metabolizer genotype on PPI response and the use adjunctive medical therapies were identified. Thirteen articles reported impacts on CYP genotypes on PPI metabolism demonstrating lower endoscopic healing rates in extensive metabolizers; however, outcomes across genotypes were more uniform with more CYP independent PPIs rabeprazole and esomeprazole. Twenty-seven publications on 11 adjunctive medications showed mixed results for adjunctive therapies including nocturnal histamine-2 receptor antagonists, promotility agents, transient lower esophageal sphincter relaxation inhibitors, and mucosal protective agents. Utilizing PPI metabolizer genotype or switching to a CYP2C19 independent PPI is a simple and conservative measure that may be useful in the setting of incomplete acid suppression. The use of adjunctive medications can be considered particularly when the physiologic mechanism for PPI nonresponse is suspected. Future studies using adjunctive medications with improved study design and patient enrollment are needed to better delineate medical management options before proceeding to antireflux interventions.

Novel and Effective Therapeutic Regimens for Helicobacter pylori in an Era of Increasing Antibiotic Resistance

Helicobacter pylori (H. pylori) is a common gastrointestinal bacterial strain closely associated with the incidence of chronic gastritis, peptic ulcers, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. A current research and clinical challenge is the increased rate of antibiotic resistance in H. pylori, which has led to a decreased H. pylori eradication rate. In this article, we review recent H. pylori infection and reinfection rates and H. pylori resistance to antibiotics, and we discuss the pertinent treatments. A PubMed literature search was performed using the following keywords: Helicobacter pylori, infection, reinfection, antibiotic resistance, bismuth, proton pump inhibitors, vonoprazan, susceptibility, quintuple therapy, dual therapy, and probiotic. The prevalence of H. pylori has remained high in some areas despite the decreasing trend of H. pylori prevalence observed over time. Additionally, the H. pylori reinfection rate has varied in different countries due to socioeconomic and hygienic conditions. Helicobacter pylori monoresistance to clarithromycin, metronidazole or levofloxacin was common in most countries. However, the prevalence of amoxicillin and tetracycline resistance has remained low. Because H. pylori infection and reinfection present serious challenges and because H. pylori resistance to clarithromycin, metronidazole or levofloxacin remains high in most countries, the selection of an efficient regimen to eradicate H. pylori is critical. Currently, bismuth-containing quadruple therapies still achieve high eradication rates. Moreover, susceptibility-based therapies are alternatives because they may avoid the use of unnecessary antibiotics. Novel regimens, e.g., vonoprazan-containing triple therapies, quintuple therapies, high-dose dual therapies, and standard triple therapies with probiotics, require further studies concerning their efficiency and safety for treating H. pylori.

Four-times-daily Dosing of Rabeprazole with Sitafloxacin, High-Dose Amoxicillin, or Both for Metronidazole-Resistant Infection with Helicobacter pylori in Japan

BACKGROUND

The bacterial resistance of Helicobacter pylori to antimicrobial agents such as clarithromycin and metronidazole has been increasing worldwide, leading to the failure of eradication treatment. Here, we present an eradication regimen consisting of four-times-daily dosing (q.i.d.) of rabeprazole with potent acid inhibition.

AIM

To investigate the efficacy of eradication therapy with rabeprazole q.i.d. and amoxicillin or sitafloxacin in Japanese infected with a metronidazole-resistant strain.

METHODS

We retrospectively investigated the efficacy of eradication regimens with rabeprazole q.i.d. for 7 days in 111 Japanese pooled patients infected with a metronidazole-resistant strain of H. pylori at Hamamatsu University School of Medicine Hospital or the Shiga University of Medical Science Hospital: 1, with sitafloxacin 100 mg twice daily (b.i.d.) (n = 82); 2, with amoxicillin 500 mg q.i.d. (n = 15); and 3, with amoxicillin q.i.d. and sitafloxacin b.i.d.-combined regimen (n = 14). Eradication status was assessed at 8 weeks via a ¹³ C-urea breath test.

RESULTS

Eradication rate on intention-to-treat analysis was 93.7% (95% confidence interval: 87.4-97.4%, 104/111), irrespective of the high prevalence of strains resistant to clarithromycin (81.1%, 90/111) and levofloxacin (42.3%, 47/111). No significant differences in eradication rates were observed among the different treatment regimens (p = .408), eradication history (p = .096) and different CYP2C19 genotypes (p = .789). On multivariate analysis, no significant risk factor for eradication failure by therapy with potent acid inhibition was seen.

CONCLUSION

In Japanese patients infected with metronidazole-resistant strains of H. pylori, eradication rates exceeding 90% can be achieved using appropriate dosing of antibiotic agents with strain susceptibility (amoxicillin q.i.d. and/or sitafloxacin b.i.d.) together with acid inhibition for a full 24 h and rabeprazole 10 mg q.i.d. These findings may be further evidence for dual therapy with rabeprazole q.i.d. and an antibiotic agent (amoxicillin q.i.d. or sitafloxacin b.i.d.) in Japanese patients with metronidazole-resistant strains.

Optimized high-dose amoxicillin-proton-pump inhibitor dual therapies fail to achieve high cure rates in China

Background\Aim: Quadruple daily administration of proton-pump inhibitor (PPI) therapy achieves potent acid inhibition, and combined with amoxicillin, with its pharmacodynamic and pharmacokinetic characteristics, may be efficient for Helicobacter pylori eradication. We compared the efficacy of two optimized high-dose dual therapies with a bismuth-containing quadruple regimen for treating H. pylori infection. Rabeprazole dosages for H. pylori eradication were also evaluated.

PATIENTS AND METHODS

Treatment-naive and H. pylori-positive subjects were recruited and randomly apportioned to three treatment groups: Group A (n = 87), rabeprazole 10 mg plus amoxicillin 750 mg (4 times/day for 14 days); Group B (n = 87), rabeprazole 20 mg plus amoxicillin 750 mg (4 times/day for 14 days); and Group C (n = 89), bismuth-containing quadruple regimen consisting of rabeprazole 20 mg, bismuth 220 mg, amoxicillin 1000 mg, and clarithromycin 500 mg (2 times/day for 14 days). Four weeks after treatment discontinuation, patients were examined for H. pylori infection by 13C-urea breath test. The rates of adverse effects, compliance, and eradication were evaluated.

RESULTS

Eradication rates in groups A, B, and C were 78.1, 81.6, and 84.3%, respectively, based on intention-to-treat analysis, or 79.1, 83.5, and 86.2%, according to per-protocol analysis. Rates of adverse events and compliance of the three groups were similar.

CONCLUSION

For treating H. pylori infection, optimized high-dose amoxicillin-PPI dual therapies failed to achieve high cure rates in China and held no advantage over a bismuth-containing quadruple regimen.

Efficacy of Magnetic Sphincter Augmentation versus Nissen Fundoplication for Gastroesophageal Reflux Disease in Short Term: A Meta-Analysis

Background. The efficacy of Magnetic Sphincter Augmentation (MSA) and its outcomes for Gastroesophageal Reflux Disease (GERD) are uncertain. Therefore, we aimed to summarize and analyze the efficacy of two treatments for GERD. Methods. The meta-analysis search was performed, using four databases. All studies from 2005 to 2016 were included. Pooled effect was calculated using either the fixed or random effects model. Results. A total of 4 trials included 624 patients and aimed to evaluate the differences in proton-pump inhibitor use, complications, and adverse events. MSA had a shorter operative time (MSA and NF: RR = -18.80, 95% CI: -24.57 to -13.04, and P = 0.001) and length of stay (RR = -14.21, 95% CI: -24.18 to -4.23, and P = 0.005). Similar proton-pump inhibitor use, complication (P = 0.19), and severe dysphagia for dilation were shown in both groups. Although there is no difference between the MSA and NF in the number of adverse events, the incidence of postoperative gas or bloating (RR = 0.71, 95% CI: 0.54-0.94, and P = 0.02) showed significantly different results. However, there is no significant difference in ability to belch and ability to vomit. Conclusions. MSA can be recommended as an alternative treatment for GERD according to their short-term studies, especially in main-features of gas-bloating, due to shorter operative time and less complication of gas or bloating.

Pharmacogenomics of proton pump inhibitors

At present, proton pump inhibitors (PPIs), as a class of strong antacid agents, are widely used in the clinical treatment of gastrointestinal diseases. PPIs achieved a strong effect of acid suppression with high specificity and long duration. However, the issue of PPI abuse exists worldwide because of the lack of relevant knowledge. Due to tremendous inter-individual differences in uptake, the clinical application of PPIs appears to be limited. Therefore, rational use of PPIs in daily clinical practice is an important research topic. In addition, PPIs were found with many side effects. CYP2C19, as one of the most important enzymes in cytochrome P450 enzyme family, is responsible for the metabolism of over 10% of drugs. The bioavailability and metabolism of PPIs are mainly affected by drug-metabolizing enzymes CYP2C19 and CYP3A4, which are located in the liver. By suppressing cytochrome P450 isoenzyme, PPIs may affect the metabolism of multiple drugs, thus leading to unwanted side effects in case of combined medication. What's more, the individual difference in PPI administration is derived from distinct molecular mechanisms mediated by CYP3A4 and/or CYP2C19. Non-genetic factors, such as combined medication and food pyramid, also impact on the effectiveness of PPIs. Gene mutations can also alter the enzymatic activity of CY2C19, thereby resulting in different blood concentrations of drugs metabolized by CYP2C19. In conclusion, PPIs have the advantages of safety and effectiveness; however, the problem of drug resistance still exists, which indicates their selective application in clinical practice. In this paper, we review the advances in pharmacogenomics of PPIs, with an aim to provide reference to individualized clinical medication.

Asia-Pacific consensus on the management of gastro-oesophageal reflux disease: an update focusing on refractory reflux disease and Barrett's oesophagus

OBJECTIVE

Since the publication of the Asia-Pacific consensus on gastro-oesophageal reflux disease in 2008, there has been further scientific advancement in this field. This updated consensus focuses on proton pump inhibitor-refractory reflux disease and Barrett's oesophagus.

METHODS

A steering committee identified three areas to address: (1) burden of disease and diagnosis of reflux disease; (2) proton pump inhibitor-refractory reflux disease; (3) Barrett's oesophagus. Three working groups formulated draft statements with supporting evidence. Discussions were done via email before a final face-to-face discussion. We used a Delphi consensus process, with a 70% agreement threshold, using Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria to categorise the quality of evidence and strength of recommendations.

RESULTS

A total of 32 statements were proposed and 31 were accepted by consensus. A rise in the prevalence rates of gastro-oesophageal reflux disease in Asia was noted, with the majority being non-erosive reflux disease. Overweight and obesity contributed to the rise. Proton pump inhibitor-refractory reflux disease was recognised to be common. A distinction was made between refractory symptoms and refractory reflux disease, with clarification of the roles of endoscopy and functional testing summarised in two algorithms. The definition of Barrett's oesophagus was revised such that a minimum length of 1 cm was required and the presence of intestinal metaplasia no longer necessary. We recommended the use of standardised endoscopic reporting and advocated endoscopic therapy for confirmed dysplasia and early cancer.

CONCLUSIONS

These guidelines standardise the management of patients with refractory gastro-oesophageal reflux disease and Barrett's oesophagus in the Asia-Pacific region.

Comparison of vonoprazan and proton pump inhibitors for eradication of Helicobacter pylori

Alternative eradication therapies for Helicobacter pylori infection are needed because of an increasing failure rate over the past decade. The aim of this study was to determine if vonoprazan, a new potassium-competitive acid blocker, showed superiority to existing proton pump inhibitors for primary eradication of H. pylori in routine clinical practice. Data for 573 patients who underwent primary H. pylori eradication therapy were retrospectively reviewed. Regimens included clarithromycin 200 mg, amoxicillin 750 mg, and an acid-suppressing drug [lansoprazole 30 mg (LAC), rabeprazole 10 mg (RAC), esomeprazole 20 mg (EAC), or vonoprazan 20 mg (VAC)] twice daily for 1 week. Eradication was successful in 73% (419/573) of patients using intention-to-treat (ITT) analysis and 76% (419/549) of patients in per-protocol (PP) analysis. The VAC group had a significantly superior eradication rate compared with the LAC and RAC groups in ITT (VAC 83%, LAC 66% and RAC 67%, p < 0.01) and PP analysis (VAC 85%, LAC 69% and RAC 70%, p < 0.01), and had a similarly high eradication rate to the EAC group (83% in ITT and 87% in PP). Although the eradication rate in the VAC and EAC groups was not significantly higher than in the LAC and RAC groups in patients with mild gastric atrophy with both ITT and PP analyses, it was significantly higher in patients with severe gastric atrophy (p < 0.01). The VAC group had a significantly higher H. pylori eradication rate than the LAC and RAC groups, and a > 80% eradication rate regardless of the degree of atrophy.

Role of bismuth in improving Helicobacter pylori eradication with triple therapy

In most regions of the world, antimicrobial resistance has increased to the point where empirical standard triple therapy for Helicobacter pylorieradication is no longer recommended. The treatment outcome in a population is calculated as the sum of the treatment success in the subpopulation with susceptible infections plus treatment success in the subpopulation with resistant infections. The addition of bismuth (i.e., 14-day triple therapy plus bismuth) can improve cure rates despite a high prevalence of antimicrobial resistance. The major bismuth effect is to add an additional 30%-40% to the success with resistant infections. The overall result is therefore dependent on the prevalence of resistance and the treatment success in the subpopulation with resistant infections (eg, with proton-pump inhibitor-amoxicillin dual therapy). Here, we explore the contribution of each component and the mechanisms of how bismuth might enhance the effectiveness of triple therapy. We also discuss the limitations of this approach and provide suggestions how triple therapy plus bismuth might be further improved.

Potent acid inhibition by vonoprazan in comparison with esomeprazole, with reference to CYP2C19 genotype

BACKGROUND

Acid inhibitory effects of proton pump inhibitors (PPIs) are influenced by CYP2C19 genotype. In contrast, the potent acid inhibition of vonoprazan is not influenced by CYP2C19 genotype.

AIM

To compare the acid inhibitory effects of vonoprazan and esomeprazole in relation to CYP2C19 genotype.

METHODS

Twenty-eight healthy Japanese volunteers [7 CYP2C19 poor metabolisers (PMs), 11 intermediate metabolisers (IMs) and 10 rapid metabolisers (RMs)] received four different regimens in a randomised crossover manner: (i) vonoprazan 20 mg twice daily (b.d.), (ii) vonoprazan 20 mg daily, (iii) esomeprazole 20 mg b.d. and (iv) esomeprazole 20 mg daily. The timing of each dosing was 1 h before a meal. Twenty-four-hour intragastric pH monitoring was performed on day 7 on each regimen.

RESULTS

In the overall genotype group, pH ≥4 holding time ratios (pH 4 HTRs) with vonoprazan b.d., vonoprazan daily, esomeprazole b.d. and esomeprazole daily were 100%, 95%, 91%, and 68% respectively. pH 5 HTRs were 99%, 91%, 84% and 54% respectively. Vonoprazan b.d. potently suppressed acid for 24 h, and was significantly superior to other regimens irrespective of CYP2C19 genotype. Vonoprazan daily was equivalent to esomeprazole b.d. in IMs and PMs, but superior in RMs. CYP2C19 genotype-dependent differences were observed in esomeprazole daily but not in vonoprazan b.d. or daily.

CONCLUSION

Vonoprazan 20 mg b.d. inhibits acid irrespective of CYP2C19 genotype, more potently than esomeprazole 20 mg b.d., pH 4 and 5 holding time ratios reached 100% and 99%, respectively.

Antibiotic resistance and CYP2C19 polymorphisms affect the efficacy of concomitant therapies for Helicobacter pylori infection: an open-label, randomized, single-centre clinical trial

OBJECTIVES

We evaluate the efficacy of concomitant therapy for Helicobacter pylori infection and the associated factors that influence it in China, where it has not previously been investigated.

METHODS

In this prospective study, 374 consecutive patients with H. pylori infection were randomly assigned to 10 day regimens of concomitant therapy with different proton pump inhibitors: esomeprazole (20 mg)/omeprazole (20 mg), amoxicillin (1000 mg), clarithromycin (500 mg) and metronidazole (400 mg). All drugs were administered twice daily. A [(13)C]urea breath test was performed at least 4 weeks after the completion of treatment. Gene polymorphisms and antimicrobial susceptibility were determined.

RESULTS

A total of 374 patients with active, uncomplicated duodenal ulcer disease were enrolled in the study (187 cases in each group). The overall eradication rate resulting from concomitant therapy was 90.7% (PP) and 86.1% (ITT) and the eradication rate was significantly higher in the group that received an esomeprazole-based regimen compared with the group that received an omeprazole-based regimen [95.4% versus 86.0%, respectively, P = 0.003 (PP) and 89.8% versus 82.4%, P = 0.036 (ITT), respectively]. Moreover, the omeprazole-based regimen was an independent risk factor for treatment failure (P = 0.039), as were CYP2C19 extensive metabolizer (P = 0.005), clarithromycin (P = 0.000) and metronidazole resistance (P = 0.000). In addition, CYP2C19 polymorphisms and antibiotic resistance had a synergistic effect on eradication rates. The majority of side effects were mild and none was serious.

CONCLUSIONS

The 10 day concomitant therapy yielded an eradication rate of nearly 90%. Antibiotic resistance, CYP2C19 polymorphisms and their interactions were closely associated with regimen efficacy.

Hp-normogram (normo-graham) for Assessing the Outcome of H. pylori Therapy: Effect of Resistance, Duration, and CYP2C19 Genotype

There have been hundreds of H. pylori eradication trials and yet doubt remains regarding the best regimen for any situation. With most regimens, treatment failure is the result of resistance to one component (e.g., clarithromycin). Thus, if one knows the treatment success with two groups (all with susceptible and with all with resistant infections), one can construct a normogram that provides a reliable estimate of the outcome at any prevalence of resistance. The same data can be used to estimate the prevalence of resistance in any clinical trial, the effects duration of therapy, and effects of any procedures to improve outcome (e.g., increasing the proton-pump inhibitor dose, the duration of therapy, etc.). Because the Hp-normo-graham can reliably predict the outcome of clinical trials, it can also obviate the need for many clinical trials in populations where resistance is common. Here, we illustrate the construction of Hp-normo-graham and its use to describe the effects of resistance, duration of therapy, attempts to improve results, and the prevalence of resistance and to obviate the need for many clinical trials.

Potent Gastric Acid Inhibition Over 24 Hours by 4-Times Daily Dosing of Esomeprazole 20 mg

BACKGROUND

When administered at a standard dose, proton pump inhibitors (PPIs) do not always provide sufficient acid inhibition for all subjects, particularly in extensive metabolizers (EMs) of CYP2C19. Whether esomeprazole at a dose of 20 mg four times daily dosing (q.i.d.) can attain sufficient acid inhibition throughout 24 h in EMs remains unclear. We therefore investigated the efficacy of esomeprazole q.i.d. for acid inhibition.

METHODS

In a randomized cross-over design, 30 Helicobacter pylori-negative healthy young Japanese volunteers received esomeprazole at a dose of 20 mg two times a day (b.i.d.) or q.i.d. for 7 days. A pH monitoring was conducted before the trial as a control and on day 7 of both regimens.

RESULTS

Median pH values in the q.i.d. regimen were significantly higher than those with the b.i.d. regimen in EMs (b.i.d.: 5.3, q.i.d.: 6.6, p = 0.022), intermediate metabolizer (IM) (b.i.d.: 5.5, q.i.d.: 6.8, p = 0.005) and poor metabolizer (PM) (b.i.d.: 6.2, q.i.d.: 7.0, p = 0.047), respectively. Median pH with the b.i.d. regimen differed significantly by CYP2C19 genotypes (p = 0.004), but not the q.i.d. regimen (p = 0.384).

CONCLUSION

Esomeprazole q.i.d. achieved potent acid inhibition in all Helicobacter pylori-negative subjects, irrespective of CYP2C19 genotype, which might be one of the rescue regimens for patients' refractory to PPI treatment.

Changes in Practice Patterns of Clopidogrel in Combination with Proton Pump Inhibitors after an FDA Safety Communication

Objectives

In 2009, the FDA issued a warning that omeprazole–a proton pump inhibitor (PPI)–reduces the antithrombotic effect of clopidogrel by almost half when taken concomitantly. This study aims to analyze the impact of the FDA Safety Communications on prescribing clopidogrel together with PPIs.

Methods

This retrospective study identified clopidogrel users from the Truven Health Analytics MarketScan Databases (01/2006–12/2012). Rates of clopidogrel-PPI combination therapy were estimated in 6-month intervals for patients with ≥1 clopidogrel prescription fill, then were analyzed pre- and post-safety communication (11/17/2009). Analyses were also conducted by grouping PPIs into CYP2C19 inhibitors (omeprazole and esomeprazole) and CYP2C19 non-inhibitors (pantoprazole, lansoprazole, dexlansoprazole, and rabeprazole).

Results

Overall, 483,074 patients met the selection criteria; of these, 157,248 used a clopidogrel-PPI combination. On average, 30.5% of patients in the pre- and 19.9% in the post-communication period used a clopidogrel-PPI combination therapy. Among clopidogrel users, the probability of using clopidogrel-PPI combinations fell by over 40% in the post-communication period (OR = 0.57; p<0.001); the proportion of patients using esomeprazole fell from 12.9% to 5.3%, and the proportion using omeprazole fell from 10.1% to 6.3%. Among combination therapy users, the probability of patients using a combination with a CYP2C19 inhibitor decreased by 53% (OR = 0.47; p<0.001); however, 31.5% of patients were still prescribed a clopidogrel-PPI combination therapy. Trends were similar for all and newly treated patients, regardless of clopidogrel indication and physician specialty.

Conclusions

The FDA Safety Communication resulted in a reduction in the number of patients undergoing combination therapy; however approximately one-third of patients still used combination therapy post-communication.

Comparative efficacy of esomeprazole and omeprazole: Racemate to single enantiomer switch

Background

Both omeprazole and its S enantiomer (esomeprazole) have been available and used to treat  symptoms of gastroesophageal reflux disease (GERD) and conditions associated with excessive stomach acid secretion for more than a decade. Controversy exists over improved efficacy of S enantiomer (esomeprazole) over parent racemate (omeprazole). However, a comparison of the clinical outcomes of these products may reveal the rationale for switching from the racemate to single enantiomer. Since enantiomers of omeprazole are equipotent, we compared the outcomes of equal doses of each product to see if both actually differ in their efficacy’s or the reported superiority of S enantiomer is just a dose effect.

Methods

A web search was carried out for randomized controlled trials with head-to-head comparisons of omeprazole and S-omeprazole. The data were abstracted and after calculating theodd ratios (OR) for the outcomes reported in each study, the combined overall odd ratios (OR’) were estimated. The random effect inverse variance method with omeprazole as the reference (OR” = 1) was used.

Results

Out of 1171 studies, 14 were deemed eligible. There was no significant difference in the therapeutic success between omeprazole and S-omeprazole as a part of triple therapy for the treatment of H. pylori in both intention-to-treat (OR’, 1.06; CI, 0.83, 1.36; p = 0.63) as well as per-protocol analysis (OR’, 1.07; CI, 0.84, 1.36; p = 0.57). For the treatment of gastro-oesophageal reflux disease, S-omeprazole was significantly but marginally superior to the racemate (OR’, 1.18; CI, 1.01, 1.38; p = 0.04). The two products were equipotent in all metrics used to assess intragastric pH except for the % patients maintaining a 24 h gastric pH above 4 (1.57; CI, 1.04, 2.381; p = 0.03).

Conclusion

The therapeutic benefit of chiral switch of omeprazole is questionable considering the substantially greater economic burden involved.

Antibiotic treatment for Helicobacter pylori: Is the end coming?

Infection with the Gram-negative pathogen Helicobacter pylori (H. pylori) has been associated with gastro-duodenal disease and the importance of H. pylori eradication is underscored by its designation as a group I carcinogen. The standard triple therapy consists of a proton pump inhibitor, amoxicillin and clarithromycin, although many other regimens are used, including quadruple, sequential and concomitant therapy regimens supplemented with metronidazole, clarithromycin and levofloxacin. Despite these efforts, current therapeutic regimens lack efficacy in eradication due to antibiotic resistance, drug compliance and antibiotic degradation by the acidic stomach environment. Antibiotic resistance to clarithromycin and metronidazole is particularly problematic and several approaches have been proposed to overcome this issue, such as complementary probiotic therapy with Lactobacillus. Other studies have identified novel molecules with an anti-H. pylori effect, as well as tailored therapy and nanotechnology as viable alternative eradication strategies. This review discusses current antibiotic therapy for H. pylori infections, limitations of this type of therapy and predicts the availability of newly developed therapies for H. pylori eradication.

Long-Term Loss of Response in Proton Pump Inhibitor-Responsive Esophageal Eosinophilia Is Uncommon and Influenced by CYP2C19 Genotype and Rhinoconjunctivitis

OBJECTIVES

Proton pump inhibitor-responsive esophageal eosinophilia (PPI-REE) is diagnosed in at least one-third of patients with suspected eosinophilic esophagitis (EoE). We aimed to evaluate the durability and factors influencing long-term efficacy of PPI therapy.

METHODS

Retrospective multicenter cohort study of patients with PPI-REE who had at least 12 months of follow-up. PPI therapy was tapered to the lowest dose, which maintained clinical remission. Primary outcomes were the proportion of patients with loss of histological response (<15 eos/HPF) and predictors of loss of response. CYP2C19 polymorphisms were determined from blood samples in a subset of patients.

RESULTS

Seventy-five PPI-REE patients were included (mean follow-up 26 months (12-85)), of whom fifty-five (73%) had sustained histological remission on low-dose PPI therapy. Loss of response was significantly higher in those patients with a CYP2C19 rapid metabolizer genotype (36% vs. 6%, P = 0.01) and with rhinoconjunctivitis (40% vs. 13%, P = 0.007). On the multivariate analysis, a CYP2C19 rapid metabolizer genotype (odds ratio (OR) 12.5; 95% confidence interval (CI): 1.3-115.9) and rhinoconjunctivitis (OR 8.6; 95% CI: 1.5-48.7) were independent predictors of loss of response. Among relapsing patients, eosinophilia was limited to the distal esophagus in 14/20 (70%). Nine of ten relapsers, with distal eosinophilia, all showing a CYP2C19 rapid metabolizer genotype, regained histological remission after PPI dose intensification.

CONCLUSIONS

Most PPI-REE patients remain in long-term remission on low-dose PPI therapy. CYP2C19 rapid metabolizer genotypes and rhinoconjunctivitis were independent predictors of loss of response to PPI, but patients frequently responded to PPI dose escalation.

Pharmacogenomic testing: the case for CYP2C19 proton pump inhibitor gene-drug pairs

The use of proton pump inhibitors (PPIs) in the treatment of gastroesophageal reflux and related diseases is increasing, especially in the pediatric population. Prolonged use of PPIs has been associated with several adverse effects, including potentially life-threatening gastric and respiratory infections, which are related to dose or to the degree of gastric acid suppression. Genetic variation in the CYP2C19 gene gives rise to poor and extensive metabolizer phenotypes, which influence PPI clearance, efficacy and exposure. A recent paper linked lansoprazole-associated respiratory infections in children with the poor metabolizer phenotype. The case is made for implementing pharmacogenomic testing for the CYP2C19-PPI gene-drug pair and to dose accordingly in order to minimize PPI-associated infections.

Cytochrome P450 in living donor liver transplantation

Cytochrome P450 metabolizes many drugs in the liver. Three genotypes of CYP2C19 with extensive, intermediate, and poor metabolizing activity, respectively, have been identified in peripheral blood of transplant recipients and new liver grafts in living donor liver transplantation (LDLT). The expression of the final genotype in liver graft biopsies depends on the donor, whereas the expression in peripheral blood mononuclear cells depends on the recipient. The metabolizing isoenzyme of the major anti-rejection agents passes through CYP3A4, CYP3A5 and MDR1, which have also been identified to have similar biological characteristics as genotype of CYP2C19 in liver tissue. Recently, pyrosequencing has been used to investigate the expressions of different genotypes in liver grafts in LDLT. This review focuses on recent findings regarding the biological expressions of the CYP2C19, CYP3A4, CYP3A5 and MRD1 genotypes in liver grafts before and after LDLT. The application of pyrosequencing may be beneficial in further research on liver transplantation. Laser capture microdissection of hepatocytes in liver grafts may be a direction for future research.

Optimised empiric triple and concomitant therapy for Helicobacter pylori eradication in clinical practice: the OPTRICON study

BACKGROUND

Empiric triple therapy for Helicobacter pylori should be abandoned when clarithromycin resistance rate is >15-20%. Optimisation of triple therapy (high-dose acid suppression and 14-day duration) can increase eradication rates by 10%.

AIM

To compare the efficacy and safety of optimised triple (OPT-TRI) and nonbismuth quadruple concomitant (OPT-CON) therapies.

METHODS

Prospective multicentre study in 16 Spanish centres using triple therapy in clinical practice. In a 3-month two-phase fashion, the first 402 patients received an OPT-TRI therapy [esomeprazole (40 mg b.d.), amoxicillin (1 g b.d) and clarithromycin (500 mg b.d) for 14 days] and the last 375 patients an OPT-CON treatment [OPT-TRI therapy plus metronidazole (500 mg b.d)].

RESULTS

Seven-hundred seventy-seven consecutive patients were included (402 OPT-TRI, 375 OPT-CON). The OPT-CON therapy achieved significantly higher eradication rates in the per-protocol [82.3% (95% CI = 78-86%) vs. 93.8% (91-96%), P < 0.001] and intention-to-treat analysis [81.3% (78-86%) vs. 90.4% (87-93%), P < 0.001]. Adverse events (97% mild/moderate) were significantly more common with OPT-CON therapy (39% vs. 47%, P = 0.016), but full compliance with therapy was similar between groups (94% vs. 92%, P = 0.4). OPT-CON therapy was the only significant predictor of successful eradication (odds ratio, 2.24; 95% CI: 1.48-3.51, P < 0.001). The rate of participating centres achieving cure rates ≥ 90% favoured OPT-CON therapy (OPT-TRI 25% vs. OPT-CON 62%).

CONCLUSIONS

Empiric OPT-CON therapy achieved significantly higher cure rates (>90%) compared to OPT-TRI therapy. Addition of metronidazole to OPT-TRI therapy increased eradication rates by 10%, resulting in more mild adverse effects, but without impairing compliance with therapy.

Efficacy of tailored Helicobacter pylori eradication treatment based on clarithromycin susceptibility and maintenance of acid secretion

BACKGROUND

Insufficient acid inhibition during Helicobacter pylori eradication treatment and bacterial resistance to antibiotics often causes eradication failure. Four times daily dosing (q.i.d.) of a proton-pump inhibitor (PPI) achieves potent acid inhibition, suggesting its potential usefulness as a regimen for eradicating H. pylori infection. Therefore, a tailored eradication regimen based on antibiotic susceptibility and maintenance of acid inhibition should have a high success rate. We investigated the efficacy of such treatment based on clarithromycin (CAM) susceptibility.

METHODS

Using 153 H. pylori-positive Japanese patients, we investigated the efficacy of tailored eradication strategy: (1) Patients infected with CAM-sensitive H. pylori were treated with a PPI (rabeprazole 10 mg q.i.d.), amoxicillin 500 mg q.i.d., and CAM 200 mg b.i.d. (n = 89), and (2) patients infected with CAM-resistant were given the same doses of rabeprazole and amoxicillin and metronidazole 250 mg b.i.d. (n = 64) for 1 week.

RESULTS

In the tailored regimen group, the overall eradication rate was 96.7% (95% CI: 92.5-98.9%, 148/153) in the intention-to-treat (ITT) analysis and 97.4% (93.4-99.3%, 148/152) in the PP analysis. The eradication rates for the CAM- and metronidazole-based treatments were similar (95.5% and 98.4%, respectively, p = .400). The tailored treatment achieved a high eradication rate in CYP2C19 rapid metabolizers who were a resistance genotype for PPI treatment (94.3% (86.0-98.4%, 66/70)).

DISCUSSION

A tailored H. pylori eradication regimen based on CAM susceptibility and maintaining acid secretion (rabeprazole 10 mg q.i.d.) is useful because it can achieve an eradication rate exceeding 95%, irrespective of eradication history, thus overcoming differences among CYP2C19 genotypes.