Proton pump inhibitors: from CYP2C19 pharmacogenetics to precision medicine

Drug-microbiota interactions: an emerging priority for precision medicine

Individual variability in drug response (IVDR) can be a major cause of adverse drug reactions (ADRs) and prolonged therapy, resulting in a substantial health and economic burden. Despite extensive research in pharmacogenomics regarding the impact of individual genetic background on pharmacokinetics (PK) and pharmacodynamics (PD), genetic diversity explains only a limited proportion of IVDR. The role of gut microbiota, also known as the second genome, and its metabolites in modulating therapeutic outcomes in human diseases have been highlighted by recent studies. Consequently, the burgeoning field of pharmacomicrobiomics aims to explore the correlation between microbiota variation and IVDR or ADRs. This review presents an up-to-date overview of the intricate interactions between gut microbiota and classical therapeutic agents for human systemic diseases, including cancer, cardiovascular diseases (CVDs), endocrine diseases, and others. We summarise how microbiota, directly and indirectly, modify the absorption, distribution, metabolism, and excretion (ADME) of drugs. Conversely, drugs can also modulate the composition and function of gut microbiota, leading to changes in microbial metabolism and immune response. We also discuss the practical challenges, strategies, and opportunities in this field, emphasizing the critical need to develop an innovative approach to multi-omics, integrate various data types, including human and microbiota genomic data, as well as translate lab data into clinical practice. To sum up, pharmacomicrobiomics represents a promising avenue to address IVDR and improve patient outcomes, and further research in this field is imperative to unlock its full potential for precision medicine.

Treatment of H. pylori infection and gastric ulcer: Need for novel Pharmaceutical formulation

Peptic ulcer disease (PUD) is one of the most prevalent gastro intestinal disorder which often leads to painful sores in the stomach lining and intestinal bleeding. Untreated Helicobacter pylori (H. pylori) infection is one of the major reasons for chronic PUD which, if left untreated, may also result in gastric cancer. Treatment of H. pylori is always a challenge to the treating doctor because of the poor bioavailability of the drug at the inner layers of gastric mucosa where the bacteria resides. This results in ineffective therapy and antibiotic resistance. Current treatment regimens available for gastric ulcer and H. pylori infection uses a combination of multiple antimicrobial agents, proton pump inhibitors (PPIs), H2-receptor antagonists, dual therapy, triple therapy, quadruple therapy and sequential therapy. This polypharmacy approach leads to patient noncompliance during long term therapy. Management of H. pylori induced gastric ulcer is a burning issue that necessitates alternative treatment options. Novel formulation strategies such as extended-release gastro retentive drug delivery systems (GRDDS) and nanoformulations have the potential to overcome the current bioavailability challenges. This review discusses the current status of H. pylori treatment, their limitations and the formulation strategies to overcome these shortcomings. Authors propose here an innovative strategy to improve the H. pylori eradication efficiency.

Evaluation of pentamidine tolerability and efficacy between CYP2C19 phenotypes

Intravenous pentamidine is used for prophylaxis against Pneumocystis jirovecii pneumonia, an infection seen in hematopoietic stem cell transplant recipients. Pentamidine is partially metabolized by CYP2C19, which is vulnerable to pharmacogenetic variation. This retrospective study evaluated allogeneic hematopoietic stem cell transplant patients who received intravenous pentamidine as P. jirovecii pneumonia prophylaxis. The primary objective was the association between CYP2C19 phenotype and discontinuation of pentamidine due to drug-related side effects based on univariate logistic regression (N = 81). Ten patients (12.3%) discontinued pentamidine because of side effects. There was no difference in discontinuation between phenotype groups (p = 0.18) or discontinuation due to side effects (p = 0.76). Overall, no association was seen between phenotypes and pentamidine-related side effects (p = 0.475). Drug discontinuation rates and P. jirovecii pneumonia infection rates were low.

A review of the long-term use of proton pump inhibitors and risk of celiac disease in the context of HLA-DQ2 and HLA-DQ8 genetic predisposition

Proton pump inhibitors (PPIs) are among the most prescribed and widely used medications; however, the long-term effects of these medications are only beginning to be investigated. Since the introduction of omeprazole in 1989, PPIs have become the first-choice treatment for esophagitis, peptic ulcer disease, Zoster-Ellison syndrome, dyspepsia, and the prevention of ulcers with non-steroidal anti-inflammatory drugs. Recent studies have specifically examined the rise in celiac disease (CD) in this context. This review explores how PPIs may impact the development of CD and highlights the need for additional research into the environmental and genetic factors that influence the development and progression of the disease. A literature search was performed using the keywords celiac disease, proton pump inhibitors, human leukocyte antigen (HLA)-DQ2, HLA-DQ8. The pathogenesis of CD is multifactorial, and human leukocyte antigens are one factor that may contribute to its development. Additionally, pharmaceuticals, such as PPIs, that cause gut dysbiosis have been linked to the inflammatory response present in CD. Recent studies have suggested that the rise in CD could be attributed to changes in the gut microbiome, highlighting the significant role that gut microbiota is proposed to play in CD pathogenesis. Although PPI therapy is helpful in reducing acid production in gastroesophageal disorders, additional information is needed to determine whether PPIs are still an appropriate treatment option with the possibility of developing CD in the future, particularly in the context of HLA-DQ2 and HLA-DQ8 predispositions. This review emphasizes the importance of personalized medicine for individuals with gastroesophageal disorders that require long-term use of PPIs.

Efficacy of Tegoprazan in Patients with Laryngopharyngeal Reflux Disease: A Preliminary Feasibility Study

Tegoprazan is a novel, potent, and highly selective potassium-competitive acid blocker that inhibits gastric acid secretion with rapid onset of action and prolonged control of gastric acidity. We performed a preliminary feasibility study to evaluate whether tegoprazan could control symptoms more effectively than a placebo in patients with laryngopharyngeal reflux disease (LPRD). In this double-blind, randomized, placebo-controlled trial, 35 patients with LPRD were randomly assigned to two groups: tegoprazan 50 mg daily and placebo. The primary endpoint was the complete resolution rate of LPRD symptoms after 8 weeks of medication, and the secondary endpoints were the complete resolution rate of LPRD symptoms after 4 weeks of medication and changes in the reflux symptom index (RSI) and reflux finding score (RFS) from baseline at 4 and 8 weeks of medication. There was no difference in the complete symptom resolution rates at 8 weeks between the tegoprazan and placebo groups (29.4% [5/17] vs. 27.8% [5/18], p = 1.000). Moreover, there was no significant difference in the complete symptom resolution rates at 4 weeks between the two groups. Compared with the baseline, both tegoprazan and placebo significantly reduced the total RSI and RFS scores after 4 and 8 weeks of medication; however, tegoprazan was not superior to the placebo. In conclusion, tegoprazan (50 mg daily) administration improved LPRD symptoms and signs. However, tegoprazan did not show superiority over placebo. Considering the potential effectiveness of tegoprazan as an acid-suppressing therapy and the possibility of type II error due to a low number of included patients herein, prospective, large-scale, multi-center studies with a higher dose of tegoprazan for a prolonged duration are required to elucidate the efficacy of tegoprazan in patients with LPRD. (ClinicalTrials.gov: NCT05871398).

Combined contributions of cytochrome P450s (CYPs) and non-enzymatic metabolism in the in vitro biotransformation of anaprazole, a novel proton pump inhibitor

Anaprazole, a new proton pump inhibitor (PPI), is designed for the treatment of acid-related diseases, such as gastric ulcers and gastroesophageal reflux. This study explored the in vitro metabolic transformation of anaprazole. The metabolic stabilities of anaprazole in human plasma and human liver microsomes (HLM) were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Then, the contribution (%) of non-enzymatic and cytochrome P450s (CYPs) enzyme-mediated anaprazole metabolism was assessed. To obtain the metabolic pathways of anaprazole, the metabolites generated in HLM, thermal deactivated HLM, and cDNA-expressed recombinant CYPs incubation systems were identified by ultra-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UPLC/Q-TOF-MS). Results showed that anaprazole was very stable in human plasma and unstable in HLM. The contribution (%) of non-enzymatic vs. CYPs enzyme-mediated metabolism was 49% vs. 51%. CYP3A4 was the major enzyme (48.3%), followed by CYP2C9 (17.7%) and CYP2C8 (12.3%), in responsible for the metabolism of anaprazole. Specific chemical inhibitors targeting CYP enzymes notably blocked the metabolic transformation of anaprazole. Six metabolites of anaprazole were identified in the non-enzymatic system, whereas 17 metabolites were generated in HLM. The biotransformation reactions mainly included sulfoxide reduction to thioether, sulfoxide oxidation to sulfone, deoxidation, dehydrogenation, O-dealkylation or O-demethylation of thioether, O-demethylation and dehydrogenation of thioether, O-dealkylation and dehydrogenation of thioether, thioether O-dealkylation and dehydrogenation of thioether, and O-dealkylation of sulfone. Both enzymatic and non-enzymatic metabolisms contribute to the clearance of anaprazole in human. Anaprazole is less likely to develop drug-drug interactions in clinical use compared to other PPIs.

Antifungal Drug-Drug Interactions with Commonly Used Pharmaceutics in European Pediatric Patients with Acute Lymphoblastic Leukemia

Leukemia is one of the leading childhood malignancies, with acute lymphoblastic leukemia (ALL) being the most common type. Invasive fungal disease is a concerning problem also at pediatric hemato-oncology units. Available guidelines underline the need for antifungal prophylaxis and give recommendations for proper treatment in various clinical scenarios. Nonetheless, antifungal agents are often involved in drug-drug interaction (DDI) occurrence. The prediction of those interactions in the pediatric population is complicated because of the physiological differences in adults, and the lack of pharmacological data. In this review, we discuss the potential DDIs between antifungal agents and commonly used pharmaceutics in pediatric hemato-oncology settings, with special emphasis on the use of liposomal amphotericin B and ALL treatment. We obtained information from Micromedex^® and Drugs.com^® interaction checking databases and checked the EudraVigilance^® database to source the frequency of severe adverse drug reactions that resulted from antifungal drug interactions. Several major DDIs were identified, showing a favorable safety profile of echinocandins and liposomal amphotericin B. Interestingly, although there are numerous available drug interaction checking tools facilitating the identification of potential serious DDIs, it is important to use more than one tool, as the presented searching results may differ between particular checking programs.

Pilot Study: Personalized Medicine in Endoscopy, Can Pharmacogenomics Predict Response to Conscious Sedation?

BACKGROUND

Adequate response to moderate (conscious) sedation varies significantly between individuals. Polymorphisms in genes encoding drug metabolizing enzymes can lead to inter-individual variability in drug efficacy, potentially influencing sedation requirements during endoscopic procedures.

OBJECTIVES

The aim of this study was to assess the potential role of inter-individual variation in inherited polymorphisms of drug-metabolizing enzymes, cytochrome P450 (CYP450), specifically CYP3A4 and CYP3A5, in sedation requirements for outpatient endoscopic procedures.

METHODS

A retrospective analysis of sedation requirements and pharmacogenomics data in 106 unique patients who received outpatient esophagogastroduodenoscopy (EGD), colonoscopy, or both between December 2011 and February 2019 was conducted. Patients were divided into two groups based on their sedation requirements during endoscopy (high vs. normal sedation).

RESULTS

Patients with reduced a CYP2C19 metabolism (poor + intermediate metabolizers) (odds ratio [OR] = 0.38, 95% confidence interval [CI]: 0.16-0.91, p = 0.03), poor CYP3A5 metabolism (OR = 0.25, 95% CI: 0.095-0.65, p = 0.0046), and poor UGT1A1 (OR = 2.76, 95% CI: 1.07-7.13, p = 0.08) had higher odds of requiring normal sedation compared to those with CYP2C19 increased metabolism, CYP3A5 intermediate metabolism, and UGT1A1 intermediate metabolism.

CONCLUSION

Information about inter-individual variation in (CYP450) genes may be useful for determining the sedation requirements for outpatient endoscopic procedures. We found that patients with reduced CYP2C19 metabolism, poor CYP3A5 metabolism, and poor UGT1A1 metabolism were more likely to require normal sedation requirements during outpatient endoscopic procedures.

Pharmacokinetics, Bioequivalence, and Safety of Esomeprazole Magnesium Enteric-Coated Capsules in Healthy Chinese Subjects

This bioequivalence study is critically important for drug production. Recently, a local pharmaceutical company produced esomeprazole magnesium enteric-coated capsules, a major drug to help to eradicate Helicobacter pylori, but the bioequivalence is not well known. The present study aimed to evaluate the bioequivalence of the 2 esomeprazole magnesium enteric-coated capsules and their pharmacokinetics and safety in 3 biological equivalence trials: fasting, feeding, and mixing. The fasting and mixing trials used single-centered randomized, open-label, single-dose, 2-treatment, 2-period, and 2-sequence crossover design, while the fed trials used single-centered, randomized, open-label, single-dose, 2-treatment, 3-period, 3-sequence partial crossover design. For the fasting and mixing trials, each of the 32 subjects was fasted overnight prior to taking the test preparations or reference preparations. In the fed trial, 54 subjects were given a high-fat meal 1 hour before the drugs were administered. Blood specimens from all subjects were collected against the light within 14 hours, with the plasma drug concentration being detected by the validated ultra-performance liquid chromatography-tandem mass spectrometry analysis method. Geometric mean ratio of maximum concentration, the area under the concentration-time curve from time zero to the last measurable concentration, and area under the concentration-time curve from time zero to infinity with 90% confidence interval were calculated. The data from fasting, mixing, and fed trials met the bioequivalence criteria. No serious adverse reactions were found, suggesting that the test and reference preparations of esomeprazole magnesium enteric capsules have similar safety profile.

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.

Prediction of gastric pH-mediated drug exposure using physiologically-based pharmacokinetic modeling: A case study of itraconazole

Abnormal gastric acidity, including achlorhydria, can act as a significant source of variability in orally administered drugs especially with pH-sensitive solubility profiles, such as weak bases, potentially resulting in an undesirable therapeutic response. This study aimed to evaluate the utility of physiologically-based pharmacokinetic (PBPK) modeling in the prediction of gastric pH-mediated drug exposure by using itraconazole, a weak base, as a case. An itraconazole PBPK model was developed on the mechanistic basis of its absorption kinetics in a middle-out manner from a stepwise in vitro-in vivo extrapolation to in vivo refinement. Afterward, an independent prospective clinical study evaluating gastric pH and itraconazole pharmacokinetics (PKs) under normal gastric acidity and esomeprazole-induced gastric hypoacidity was conducted for model validation. Validation was performed by comparing the predicted data with the clinical observations, and the valid model was subsequently applied to predict PK changes under achlorhydria. The developed itraconazole PBPK model showed reasonable reproducibility for gastric pH-mediated exposure observed in the clinical investigation. Based on the model-based simulations, itraconazole exposure was expected to be decreased up to 65% under achlorhydria, and furthermore, gastric pH-mediated exposure could be mechanistically interpreted according to sequential variation in total solubility, dissolution, and absorption. This study suggested the utility of PBPK modeling in the prediction of gastric pH-mediated exposure, especially for drugs whose absorption is susceptible to gastric pH. Our findings will serve as a leading model for further mechanistic assessment of exposure depending on gastric pH for various drugs, ultimately contributing to personalized pharmacotherapy.

Proton Pump Inhibitors, Kidney Damage, and Mortality: An Updated Narrative Review

Since their approval by the Food and Drug Administration (FDA) in 1989, proton pump inhibitors (PPIs) have become one of the most highly utilized drugs in the United States, assuming a position as one of the top 10 most prescribed medications in the country. The purpose of PPIs is to limit the amount of gastric acid secreted by the parietal cells via irreversible inhibition of the H+/K+-ATPase pump, therefore maintaining an elevated gastric acid pH of greater than 4 for 15-21 h. Even though PPIs have many clinical uses, they are not without their adverse effects, mimicking achlorhydria. Besides electrolyte abnormalities and vitamin deficiencies, long-term use of PPIs has been linked to acute interstitial nephritis, bone fractures, poor COVID-19 infection outcomes, pneumonia, and possibly an increase in all-cause mortality. The causality between PPI use and increased mortality and disease risk can be questioned since most studies are observational. Confounding variables can greatly affect an observational study and explain the wide-ranging associations with the use of PPIs. Patients on PPIs are generally older, obese, sicker with a higher number of baseline morbidities, and on more medications than the compared PPI non-users. These findings suggest that PPI users are at a higher risk of mortality and complications based on pre-existing conditions. This narrative review aims to update readers on the concerning effects that proton pump inhibitor use can have on patients and give providers a resource to create informed decisions on appropriate PPI use.

Factors associated with treatment failure, and possible applications of probiotic bacteria in the arsenal against Helicobacter pylori

INTRODUCTION

Helicobacter pylori is a widespread helical Gram-negative bacterium, which causes a variety of stomach disorders, such as peptic ulcer, chronic atrophic gastritis, and gastric cancer. This microbe frequently colonizes the mucosal layer of the human stomach and survives in the inhospitable microenvironment, by adapting to this hostile milieu.

AREAS COVERED

In this extensive review, we describe conventional antibiotic treatment regimens used against H. pylori including, empirical, tailored, and salvage therapies. Then, we present state-of-the-art information about reasons for treatment failure against H. pylori. Afterward, the latest advances in the use of probiotic bacteria against H. pylori infection are discussed. Finally, we propose a polymeric bio-platform to provide efficient delivery of probiotics for H. pylori infection.

EXPERT OPINION

For effective probiotic delivery systems, it is necessary to avoid the early release of probiotics at the acidic stomach pH, to protect them against enzymes and antimicrobials, and precisely target H. pylori bacteria which have colonized the antrum area of the stomach (basic pH).

Rescue therapy for refractory Helicobacter pylori infection: current status and future concepts

Helicobacter pylori infection is an important issue worldwide, and several guidelines have been published for clinicians to achieve successful eradication. However, there are still some patients who remain infected with H. pylori after treatment. Clinicians should identify the reasons that caused treatment failure and find strategies to manage them. We have searched and organized the literature and developed methods to overcome factors that contribute to prior treatment failure, such as poor compliance, inadequate intragastric acid suppression, and antibiotic resistance. To improve compliance, telemedicine or smartphone applications might play a role in the modern world by increasing doctor-patient relationships, while concomitant probiotics could be administered to reduce adverse effects and enhance adherence. For better acid suppression, high-potency and high-dose proton-pump inhibitors or potassium-competitive acid blockers have preferable efficacy. To overcome antibiotic resistance, susceptibility tests either by culture or by genotyping are the most commonly used methods and have been suggested for antibiotic selection before rescue therapy, but empirical therapy according to detailed medical history could be an alternative. Eradication with a longer treatment period (14 days) has a better outcome than shorter period (7 or 10 days). Ultimately, clinicians should select antibiotics based on the patient's history of drug allergy, previous antibiotic exposure, local antibiotic resistance, available medications, and cost. In addition, identifying patients with a high risk of cancer and shared decision-making are also essential for those who have experienced eradication failure.

Development of a point-of-care genetic test for effective treatment of ischaemic stroke: an early model-based cost-effectiveness analysis

Background: People who have experienced a stroke are at high risk of recurrent strokes. Clopidogrel is prescribed to people who have had a non-cardioembolic stroke. There is evidence that clopidogrel is not effective for patients with CYP2C19 loss-of-function alleles. Pharmacogenetic testing is a potential strategy to identify such patients and guide prescription of appropriate antiplatelet treatment. This study aimed to provide an early estimate of the cost-effectiveness of using a point-of-care pharmacogenetic CYP2C19 test in the UK National Health System. Methods: A decision-analytic model comprising a linked decision tree and Markov model were created in R comparing pharmacogenetic testing with current prescribing practice. In the pharmacogenetic testing arm, patients identified to have one of three loss-of-function alleles were prescribed modified-release dipyridamole and aspirin or aspirin alone. Indicative data were sourced from reviews of the literature supported by expert consultation to select the most appropriate value for the input parameters. The healthcare costs (£;2021) and quality adjusted life years resulting from each strategy were estimated and the incremental cost-effectiveness of testing calculated. Deterministic threshold analysis and probabilistic sensitivity analysis (PSA) was conducted to account for uncertainty in the parameter estimates. Results: The pharmacogenetic testing strategy generated 0.107 additional QALYs per patient tested and saved £512. Pharmacogenetic testing dominated current prescribing practice. The results were robust to extreme changes in key input variables. The PSA suggested that there was a 77% chance that pharmacogenetic testing would be cost-effective with a 62% chance it is cost-saving. Conclusions: A point-of-care pharmacogenetic test to guide prescription of clopidogrel for people who have experienced a stroke has the potential to provide a significant health gain by preventing secondary strokes and may save resources in the health system. This early economic analysis has also informed the direction for future research.

Efficacy of tegoprazan-based bismuth quadruple therapy compared with bismuth quadruple therapy for Helicobacter pylori infection: A randomized, double-blind, active-controlled study

BACKGROUND

Bismuth-based quadruple therapy (BQT) is recommended as the first-line empirical therapy for Helicobacter pylori eradication as it is not associated with resistance. However, few studies have investigated the use of potassium-competitive acid blockers for BQT.

AIM

To investigate the efficacy and safety profiles of tegoprazan-based BQT (TBMT) versus lansoprazole-based BQT (LBMT) for H. pylori eradication.

METHODS

We included patients older than 18 with an H. pylori infection without a history of H. pylori eradication who visited four university-affiliated hospitals between March 2020 and December 2021. H. pylori infection was diagnosed using a rapid urease test or Giemsa staining. Patients were randomly assigned to the TBMT or LBMT group.

RESULTS

217 subjects were randomly allocated to receive either TBMT (n = 108) or LBMT (n = 109) therapy. Intention-to-treat (ITT) eradication rates of TBMT and LBMT were 80.0% and 77.4% (95% confidence interval [CI]: -8.4 to 13.7, p = 0.0124), respectively. Corresponding modified ITT rates were 90.3% and 84.5% (95% CI: -3.6 to 15.2, p = 0.0005), respectively. Per-protocol (PP) eradication rates of TBMT and LBMT were 90.2% and 82.4% (95% CI: -2.5 to 18.2, p = 0.0003), respectively. There was no significant difference in the rate of adverse events between the TBMT and LBMT groups (39.1% vs. 43.4%, p = 0.5211). TBMT showed higher eradication rates than that of LBMT in ITT, m-ITT, and PP analysis.

CONCLUSION

TBMT showed a noninferior eradication rate and similar adverse events to LBMT as a first-line eradication regimen. Our results suggest that tegoprazan might be substituted for proton pump inhibitors in H. pylori eradication regimens.

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.

Bortezomib Pharmacogenetic Biomarkers for the Treatment of Multiple Myeloma: Review and Future Perspectives

Multiple myeloma (MM) is a hematological neoplasm for which different chemotherapy treatments are used with several drugs in combination. One of the most frequently used drugs for the treatment of MM is the proteasome inhibitor bortezomib. Patients treated with bortezomib are at increased risk for thrombocytopenia, neutropenia, gastrointestinal toxicities, peripheral neuropathy, infection, and fatigue. This drug is almost entirely metabolized by cytochrome CYP450 isoenzymes and transported by the efflux pump P-glycoprotein. Genes encoding both enzymes and transporters involved in the bortezomib pharmacokinetic pathway are highly polymorphic. The response to bortezomib and the incidence of adverse drug reactions (ADRs) vary among patients, which could be due to interindividual variations in these possible pharmacogenetic biomarkers. In this review, we compiled all pharmacogenetic information relevant to the treatment of MM with bortezomib. In addition, we discuss possible future perspectives and the analysis of potential pharmacogenetic markers that could influence the incidence of ADR and the toxicity of bortezomib. It would be a milestone in the field of targeted therapy for MM to relate potential biomarkers to the various effects of bortezomib on patients.

Randomised clinical trial: Safety, tolerability, pharmacodynamics and pharmacokinetics of zastaprazan (JP-1366), a novel potassium-competitive acid blocker, in healthy subjects

BACKGROUND

Zastaprazan (JP-1366) is a novel potassium-competitive acid blocker with favourable preclinical safety and efficacy profile being developed for the treatment of acid-related diseases.

AIMS

To investigate the safety, tolerability, pharmacodynamics and pharmacokinetics of zastaprazan.

METHODS

A randomised, open-label, placebo- and active-controlled, single and multiple ascending dose clinical trial was conducted in healthy Korean male subjects. Intragatric pH and serum gastrin were measured to assess the pharmacodynamics, while serial blood and urine samples were collected to assess the pharmacokinetics. Pharmacogenomic evaluation was conducted to explore genetic variants, which can affect the pharmacodynamics and pharmacokinetics. Safety and tolerability including hepatotoxicity were evaluated.

RESULTS

Suppression of gastric acid secretion increased as the dose of zastaprazan increased. The percentage of time that gastric pH was over 4 (%Time pH >4) with zastaprazan 20 mg (85.19%) and 40 mg (91.84%) were similar to or greater than that with esomeprazole 40 mg (72.06%). Zastaprazan was rapidly absorbed within 2 h and eliminated with a half-life of 6-10 h. Pharmacogenomic analysis found no genetic variant of drug metabolising enzymes including CYP2C19 or drug transporters associated with the exposure of zastaprazan. Zastaprazan was well tolerated with no clinically significant changes in safety and tolerability assessments.

CONCLUSIONS

Zastaprazan was safe and well tolerated after a single oral dose up to 60 mg and multiple oral doses up to 40 mg. It also showed rapid, potent suppression of gastric acid secretion. Pharmacodynamic and pharmacokinetic profile of zastaprazan was suitable for treatment of patients with acid-related diseases.

Using single cell atlas data to reconstruct regulatory networks

Inference of global gene regulatory networks from omics data is a long-term goal of systems biology. Most methods developed for inferring transcription factor (TF)-gene interactions either relied on a small dataset or used snapshot data which is not suitable for inferring a process that is inherently temporal. Here, we developed a new computational method that combines neural networks and multi-task learning to predict RNA velocity rather than gene expression values. This allows our method to overcome many of the problems faced by prior methods leading to more accurate and more comprehensive set of identified regulatory interactions. Application of our method to atlas scale single cell data from 6 HuBMAP tissues led to several validated and novel predictions and greatly improved on prior methods proposed for this task.

The concomitant use of proton pump inhibitors and BRAF/MEK inhibitors in metastatic melanoma

BACKGROUND

Proton-pump inhibitors (PPIs) are commonly used by patients with cancer, although they could reduce the absorption of oral anticancer targeted therapies. The US Food and Drug Administration states that the effect of PPIs on the efficacy of dabrafenib use by patients with metastatic melanoma is unknown. As a precautionary measure, the European Society for Medical Oncology recommends avoiding PPIs for patients receiving dabrafenib.

OBJECTIVES

To determine the effect of the concomitant use of PPIs and BRAF/MEK inhibitors in patients with metastatic melanoma.

METHODS

Patients with advanced melanoma receiving BRAF/MEK inhibitors as first-line treatments between 2015 and 2017 in France were selected using the French National Health Insurance database. We compared time-to-treatment discontinuation (TTD) and overall survival (OS) according to concomitant PPI exposure. We balanced the baseline characteristics of patients exposed and nonexposed to PPIs using an overlap weighting method based on a propensity score.

RESULTS

The metastatic melanoma cohort comprised 1028 patients receiving BRAF/MEK inhibitors, including 361 (35.1%) patients using PPIs. PPI users had more comorbidities and a more severe metastatic disease. After having equally distributed metastatic sites and comorbidities across patients exposed and nonexposed to PPIs, concomitant PPI use was not associated with shorter TTD [weighted hazard ratio (wHR) 1.03, 95% confidence interval (CI) 0.86-1.24] or OS (wHR 1.11, 95% CI 0.88-1.39). Consistent results were observed when restricting the population to patients receiving dabrafenib, or when narrowing exposure to PPIs with stronger inhibition of cytochromes.

CONCLUSIONS

In a population-based cohort of patients with advanced melanoma, the concomitant use of PPIs and BRAF/MEK inhibitors was not associated with worse outcome.

Pharmacokinetics and bioequivalence evaluation of omeprazole and sodium bicarbonate dry suspensions in healthy Chinese volunteers

Omeprazole and sodium bicarbonate dry suspension are effective treatments for acid-related disorders. This study compared the bioequivalence and safety of the two formulations of omeprazole and sodium bicarbonate powder and assessed how CYP2C19 gene polymorphisms affect pharmacokinetics (PK). A single-center, randomized, single-dose, 2-sequence and 2-period crossover method was performed in forty healthy Chinese subjects. Blood samples were collected after a single dose for PK (AUC0-∞, AUC0-t, and Cmax) analysis. The concentrations of Omeprazole in human plasma were determined by HPLC-MS/MS. Besides, the gene polymorphisms of CYP2C19 were assessed by Sanger sequencing. The geometric mean ratios (90% confidence interval) [GMR (95% CI)] of Test/Reference preparation for Cmax: 95.2% (88.48%, 102.43%), AUC0-t: 97.47% (94.4%, 101.02%), AUC0-∞: 97.68% (94.27%, 101.21%) were within the range of 80.00-125.00%. The non-parametric test showed no statistical difference in Tmax between the two groups (p > 0.05). All drugs were well tolerated, no severe adverse reactions occurred, and no significant differences in adverse events between the two drugs. For CYP2C19 gene polymorphisms, the results showed that of 40 subjects, 12 subjects were extensive metabolizers, 24 were intermediate metabolizers, and 4 were poor metabolizers, the frequency of metabolic genotypes were 30%, 60%, and 10%. And the allele distributions for CYP2C19 were *1, *2, and *3 at 60%, 38.75%, and 1.25%. Both the CYP2C19 alleles and metabolic genotypes were consistent with other studies in Chinese. The results of PK parameters showed that different genotypes of CYP2C19 lead to significant differences in t1/2, AUC0-t, AUC0-∞ and Cmax, but no significant differences in Tmax in each group. At the same time, we confirmed that the PK parameters of the test and reference had no differences between the males and females. This study has shown that the pharmacokinetic parameters of the two formulations are not significantly different, which showed bioequivalence and exemplary safety. CYP2C19 gene polymorphism significantly differed in the PK parameters of omeprazole sodium bicarbonate powder.

Vietnam Association of Gastroenterology (VNAGE) consensus on the management of Helicobacter pylori infection

Helicobacter pylori (H. pylori) infection is prevalent and has a rapidly increasing antibiotic resistance rate in Vietnam. Reinfection is quite common, and gastric carcinoma remains one of the most common malignancies, which is not uncommon to develop after successful eradication. The purpose of this consensus is to provide updated recommendations on the management of H. pylori infection in the country. The consensus panel consisted of 32 experts from 14 major universities and institutions in Vietnam who were invited to review the evidence and develop the statements using the Delphi method. The process followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. The consensus level was defined as ≥80% for agreement on the proposed statements. Due to the limited availability of high-quality local evidence, this consensus was also based on high-quality evidence from international studies, especially those conducted in other populations in the Asia-Pacific region. The panel finally reached a consensus on 27 statements after two voting rounds, which consisted of four sections (1) indications for testing and selection of diagnostic tests (2), treatment regimens, (3) post-treatment confirmation of H. pylori status, and (4) reinfection prevention methods and follow-up after eradication. Important issues that require further evidence include studies on third-line regimens, strategies to prevent H. pylori reinfection, and post-eradication follow-up for precancerous gastric lesions. We hope this consensus will help guide the current clinical practice in Vietnam and promote multicenter studies in the country and international collaborations.

Which four medication classes have important pharmacogenetic considerations?

ABSTRACT

Medications often are prescribed without knowledge of a patient's pharmacogenetic profile. Initial therapy may require subsequent modification due to adverse reactions or lack of efficacy. Although many variables, including changes in pharmacokinetics, pharmacodynamics, or patient nonadherence, may account for these outcomes, information about a patient's ability to metabolize or transport drugs across membranes may be used to optimize therapy, resulting in improved medication outcomes.

Effect and safety of anaprazole in the treatment of duodenal ulcers: a randomized, rabeprazole-controlled, phase III non-inferiority study

BACKGROUND

The pharmacokinetic and clinical behaviors of many proton pump inhibitors (PPIs) in peptic ulcer treatment are altered by CYP2C19 genetic polymorphisms. This non-inferiority study evaluated the efficacy and safety of the novel PPI anaprazole compared with rabeprazole. We also explored the influence of Helicobacter pylori ( H. pylori ) infection status and CYP2C19 polymorphism on anaprazole.

METHODS

In this multicenter, randomized, double-blind, double-dummy, positive-drug parallel-controlled, phase III study, Chinese patients with duodenal ulcers were randomized 1:1 to receive rabeprazole 10 mg + anaprazole placebo or rabeprazole placebo + anaprazole 20 mg once daily for 4 weeks. The primary efficacy endpoint was the 4-week ulcer healing rate assessed by blinded independent review. Secondary endpoints were the proportion of patients with improved overall and individual duodenal ulcer symptoms at 4 weeks. Furthermore, exploratory subgroup analysis of the primary endpoint by H. pylori status and CYP2C19 polymorphism was conducted. Adverse events were monitored for safety. Non-inferiority analysis was conducted for the primary endpoint.

RESULTS

The study enrolled 448 patients (anaprazole, n = 225; rabeprazole, n = 223). The 4-week healing rates were 90.9% and 93.7% for anaprazole and rabeprazole, respectively (difference, -2.8% [95% confidence interval, -7.7%, 2.2%]), demonstrating non-inferiority of anaprazole to rabeprazole. Overall duodenal ulcer symptoms improved in 90.9% and 92.5% of patients, respectively. Improvement rates of individual symptoms were similar between the groups. Healing rates did not significantly differ by H. pylori status or CYP2C19 genotype for either treatment group. The incidence of treatment-emergent adverse events was similar for anaprazole (72/220, 32.7%) and rabeprazole (84/219, 38.4%).

CONCLUSIONS

The efficacy of anaprazole is non-inferior to that of rabeprazole in Chinese patients with duodenal ulcers.

REGISTRATION

ClinicalTrials.gov, NCT04215653.

Clinical outcomes of concomitant use of proton pump inhibitors and regorafenib in patients with metastatic colorectal cancer: a multicenter study

AIM

To compare survival outcomes, response rates, and adverse events (AEs) in proton pump inhibitor (PPI) user and non-user patients with metastatic colorectal cancer (mCRC) treated with regorafenib.

METHODS

We included 272 patients with mCRC treated with regorafenib in this study. Patients were divided into two categories according to their status of PPI use. The primary endpoint was overall survival (OS). The secondary endpoints were time to treatment failure (TTF), response rates, and safety. To exclude immortal time bias in survival analyses, we compared PPI non-user patients and all patients.

RESULTS

There were 141 and 131 patients in the PPI non-user and user groups. Baseline characteristics were similar in each group. Pantoprazole was the most used PPI. At the median 35.2 (95% confidence interval (CI): 32.6-37.9) months follow-up, the median OS was similar in PPI non-user and all patients (6.9 months (95% CI: 5.3-8.5) and 7.7 months (95% CI:6.6-8.8), p = 0.913). TTF was also similar in PPI non-user and all patients (3.3 months (95% CI: 2.7-3.9) and 3.5 months (95% CI: 3.0-4.0), p = 0.661). In multivariable analysis, no statistically significant difference was observed between PPI user and non-user groups in OS and TTF (hazard ratio (HR), 0.99; 95% CI, 0.77-1.28; p = 0.963 for OS; HR, 0.93; 0.77-1.20, p = 0.598 for TTF). The objective response rates (ORR) were similar in the PPI non-user and user groups (19.8% and 16.8%, p = 0.455). The rates of any grade AEs were also similar in each group.

CONCLUSION

This study found no worse outcome in the combined use of PPI and regorafenib among patients with mCRC.

Effects of CYP2C19 genetic polymorphisms on the cure rates of H. pylori in patients treated with the proton pump inhibitors: An updated meta-analysis

Background: The cure rates of Helicobacter pylori (H. pylori) treatment using a proton pump inhibitor (PPI) are gradually decreasing due to antibiotic resistance, poor compliance, high gastric acidity, and cytochrome P450 2C19 (CYP2C19) polymorphism, and the effects of PPI depend on metabolic enzymes, cytochrome P450 enzymes. The aim of this meta-analysis was to determine whether CYP2C19 polymorphisms affect H. pylori cure rates in patients treated with different proton pump inhibitors (PPIs) according to stratified analysis.

Materials and methods: The literature was searched with the key words “H. pylori” and “CYP2C19” in PubMed, CNKI, and Wanfang up to 31 May 2022, and the studies were limited to clinical observational or randomized controlled trials (RCTs). Finally, seven RCTs and 29 clinical observational studies met the inclusion criteria and were used for the meta-analysis via STATA version 16.

Results: The cure rates were significantly different between genotypes of homozygous extensive metabolizers (EM) and poor metabolizers (PM) (OR = 0.58, 95% CI: 0.47–0.71) and between EM and heterozygous extensive metabolizers (IM) (OR = 0.71, 95% CI: 0.59–0.86), but not between IM and PM. Moreover, there was a significantly lower H. pylori cure rate in EM subjects than that in IM subjects when treated with omeprazole (66.4% vs. 84.1%), lansoprazole (76.1% vs. 85.6%), but not rabeprazole, esomeprazole, or pantoprazole. In addition, there was a significantly lower H. pylori cure rate in EM subjects than that in IM subjects when treated with a PPIs for 7 days (77.4% vs. 82.1%), but not 14 days (85.4% vs. 90.0%).

Conclusion: Carriers of CYP2C19 loss-of-function variant alleles (IM and PM) exhibit a significantly greater cure rate of H. pylori than noncarriers (EM) regardless of other factors (84.7% vs. 79.2%). In addition, pantoprazole- and rabeprazole-based quadruple therapy for H. pylori treatment is less dependent on the CYP2C19 genotype and should be prioritized in Asian populations with H. pylori.

Progress in research of pathogenesis of refractory gastroesophageal reflux disease

Refractory gastroesophageal reflux disease (rGERD) is a common clinical disease with many pathogenic factors, complex mechanisms, and increasing incidence. At present, scholars believe that the pathogenesis of rGERD is closely related to intra- and extra-esophageal factors. Elucidating the mechanism of rGERD can contribute to the diagnosis and treatment of the disease. This paper summarizes the current progress in the research of the pathogenesis of rGERD, and puts forward our own thoughts and prospects for the disease, in order to provide ideas for the in-depth study of the pathogenesis of rGERD.

Vonoprazan Triple and Dual Therapy for Helicobacter pylori Infection in the United States and Europe: Randomized Clinical Trial

BACKGROUND & AIMS

Novel, effective treatments for Helicobacter pylori infection are needed. This study evaluated the efficacy of vonoprazan, a potassium-competitive acid blocker, vs standard treatment on H pylori eradication in the United States and Europe.

METHODS

In a randomized, controlled, phase 3 trial, treatment-naïve adults with H pylori infection were randomized 1:1:1 to open-label vonoprazan dual therapy (20 mg vonoprazan twice daily; 1 g amoxicillin 3 times daily), or double-blind triple therapy twice a day (vonoprazan 20 mg or lansoprazole 30 mg; amoxicillin 1 g; clarithromycin 500 mg) for 14 days. The primary outcome was noninferiority in eradication rates in patients without clarithromycin- and amoxicillin-resistant strains (noninferiority margin = 10%). Secondary outcomes assessed superiority in eradication rates in clarithromycin-resistant infections, and in all patients.

RESULTS

A total of 1046 patients were randomized. Primary outcome eradication rates (nonresistant strains): vonoprazan triple therapy 84.7%, dual therapy 78.5%, vs lansoprazole triple therapy 78.8% (both noninferior; difference 5.9%; 95% confidence interval [CI], -0.8 to 12.6; P < .001; difference -0.3%; 95% CI, -7.4 to 6.8; P = .007, respectively). Eradication rates in clarithromycin-resistant infections: vonoprazan triple therapy 65.8%, dual therapy 69.6%, vs lansoprazole triple therapy 31.9% (both superior; difference 33.9%; 95% CI, 17.7-48.1; P < .001; difference 37.7%; 95% CI, 20.5-52.6; P < .001, respectively). In all patients, vonoprazan triple and dual therapy were superior to lansoprazole triple therapy (80.8% and 77.2%, respectively, vs 68.5%, difference 12.3%; 95% CI, 5.7-18.8; P < .001; difference 8.7%; 95% CI, 1.9-15.4; P = .013). Overall frequency of treatment-emergent adverse events was similar between vonoprazan and lansoprazole regimens (P > .05).

CONCLUSION

Both vonoprazan-based regimens were superior to proton pump inhibitor-based triple therapy in clarithromycin-resistant strains and in the overall study population.

CLINICALTRIALS

gov; NCT04167670.

Pharmacogenetic Expression of CYP2C19 in a Pediatric Population

Genetic variability in CYP2C19 may be associated with both lack of efficacy and toxicity of drugs due to its different metabolic status based on the presence of particular alleles. This literature review summarizes current knowledge relative to the association or treatment adaptation based on CYP2C19 genetics in a pediatric population receiving drugs metabolized by CYP2C19, such as voriconazole, antidepressants, clopidogrel and proton pump inhibitors. Additionally, we also presented one of the approaches that we developed for detection of variant alleles in the CYP2C19 gene. A total of 25 articles on PubMed were retained for the study. All studies included pediatric patients (age up to 21 years) having benefited from an assessment of CYP2C19. CYP2C19 poor and intermediate metabolizers exhibit a higher trough plasma concentration of voriconazole, and PPIs compared to the rapid and ultra-rapid metabolizers. The pharmacogenetic data relative to CYP2C19 and clopidogrel in the pediatric population are not yet available. CYP2C19 poor metabolizers have a higher trough plasma concentration of antidepressants compared to the rapid and the ultra-rapid metabolizers. Modification of allele-specific PCR through the introduction of artificial mismatch is presented. CYP2C19 genotyping remains a powerful tool needed to optimize the treatment of children receiving voriconazole, PPIs, and anti-depressants.

Proton pump inhibitor in the prevention of upper gastrointestinal mucosal injury associated with dual antiplatelet therapy after coronary artery bypass grafting (DACAB-GI-2): study protocol for a randomized controlled trial

Background

Dual antiplatelet therapy (DAPT) is recommended in secondary prevention after coronary artery bypass grafting (CABG), but it is inevitably associated with the risk of bleeding, of which gastrointestinal bleeding accounts for more than half. Proton pump inhibitors (PPIs) may increase the risk of major cardiovascular adverse events when reducing the risk of upper gastrointestinal bleeding. Therefore, the optimal duration of a PPI in combination with DAPT is unclear.

Methods

The “Proton Pump Inhibitor Preventing Upper Gastrointestinal Injury in Patients on Dual Antiplatelet Therapy after CABG” (DACAB-GI-2) study is a prospective, single-center, open-label, parallel, randomized controlled trial. A total of 232 eligible subjects who are scheduled or initiated on DAPT (clopidogrel plus aspirin or ticagrelor plus aspirin) for 12 months immediately after CABG will be enrolled and be randomized in a 1:1 ratio to either a 12-month pantoprazole treatment arm or a 1-month treatment arm. The primary outcome is to assess the rate of gastroduodenal erosions and ulcers evaluated by esophagogastroduodenoscopy (EGD) within 12 months after randomization, based on the modified Lanza score. Secondary outcomes include reflux esophagitis and upper gastrointestinal bleeding. Other pre-specified outcomes include major adverse cardiovascular events, graft failure, and all-cause death.

Discussion

This study aims to compare the efficacy and safety of 12 months and 1 month of pantoprazole treatment in preventing DAPT-related upper gastrointestinal mucosal injury after CABG.

Trial registration

ClinicalTrials.gov NCT03908593.

An update on drug-drug interactions associated with proton pump inhibitors

INTRODUCTION

Proton pump inhibitors (PPIs) block the gastric H/K-ATPase, therefore inhibiting acid gastric secretion, leading to an increased pH (>4). They account for an extremely high number of prescriptions worldwide. Numerous drug-drug interactions have been described with PPIs, but all the described interactions do not have clinical significance.

AREAS COVERED

This review will discuss the latest updates on drug-drug interactions with PPIs, focusing on the last ten-year publications in the following areas: anti-infective agents, anticancer drugs, antiplatelet agents and anticoagulants, and antidiabetics.

EXPERT OPINION

Although pharmacokinetic interactions of PPIs have been described with many drugs, their clinical relevance remains controversial. However, given the extremely high number of people being treated with PPIs, clinicians should remain vigilant for interactions that may be clinically significant and require dose adjustment or therapeutic monitoring. Interestingly, not all PPIs have the same pharmacokinetic and pharmacodynamic profile, with some having a strong potential to inhibit CYP2C19, such as omeprazole, esomeprazole and lansoprazole, while others, pantoprazole, rabeprazole and dexlansoprazole, are weak CYP2C19 inhibitors. These may be preferred depending on co-prescribed treatments.In addition, new formulations have been developed to prevent some of the gastric pH-dependent drug interactions and should be evaluated in further large-scale prospective comparative studies.

Randomised clinical trial: comparison of efficacy and adverse effects of a standard triple clarithromycin-containing regimen with high-dose amoxicillin and bismuth therapy in Helicobacter pylori eradication

BACKGROUND

The clarithromycin-based triple therapy is the most prescribed Helicobacter pylori eradication regimen in Europe; it causes adverse effects in a significant proportion of subjects, leading to discontinuation. Alternative therapies are required because of increasing clarithromycin resistance or to decrease the adverse effects.

AIMS

We compared the efficacy and spectrum of adverse effects of clarithromycin-based triple therapy with the high-dose amoxicillin/bismuth regimen.

METHODS

A randomised clinical trial enrolled healthy individuals aged 40-64 years. H. pylori was assessed with a 13C-urea breath test. In total 579 H. pylori-positive subjects were randomly allocated in two groups: group 1: clarithromycin 500 mg, amoxicillin 1000 mg, esomeprazole 40 mg, all twice daily; group 2: bismuth subcitrate 240 mg twice daily, amoxicillin 1000 mg three times daily, esomeprazole 40 mg twice daily. Regimens were administered for 14 days.Information on treatment completion and adverse effects were collected via a telephone interview at 21-28 days after medication delivery. The efficacy was assessed by UBT 6 months after the treatment.

RESULTS

We analysed 483 subjects for adverse effects (248 vs. 235 respectively). Furthermore, 316 subjects were analysed for efficacy. In per-protocol analysis, a higher efficacy was seen in group 1 (88.4 vs. 77.0%; P < 0.001); no difference was observed in compliance (90.3 and 91.2%). Therapy-related adverse effects were more common in group 1 (56.9 vs. 40.0%; P < 0.01). In intention-to-treat analysis no statistical difference in efficacy was revealed.

CONCLUSIONS

Bismuth-based high-dose amoxicillin therapy showed a lower efficacy but was less frequently associated with adverse effects. Further research is required to examine the high-dose amoxicillin and bismuth-containing regimens in various populations to maximise eradication efficacy.

Experience with comprehensive pharmacogenomic multi-gene panel in clinical practice: a retrospective single-center study

AIM

To assess the prevalence of actionable pharmacogenetic interventions in patients who underwent pharmacogenetic testing with a multi-gene panel.

METHODS

We retrospectively reviewed single-center electronic health records. A total of 319 patients were enrolled who underwent pharmacogenomic testing with the RightMed test panel using TaqMan quantitative real-time PCR method and copy number variation analysis to determine the SNPs in the 27 target genes.

RESULTS

Actionable drug-gene pairs were found in 235 (73.7%) patients. Relevant guidelines on genotype-based prescribing were available for 133 (56.7%) patients at the time of testing. Based on the patients' genotype, 139 (43.6%) patients were using at least one drug with significant pharmacogenetic interactions.

CONCLUSION

Two out of three patients had at least one drug-gene pair in their therapy. Further studies should assess the clinical effectiveness of integrating pharmacogenomic data into patients' electronic health records.

Proton Pump Inhibitor Use and Risk of Gastric Cancer: Current Evidence from Epidemiological Studies and Critical Appraisal

Proton pump inhibitors (PPIs) are used for maintaining or improving gastric problems. Evidence from observational studies indicates that PPI therapy is associated with an increased risk of gastric cancer. However, the evidence for PPIs increasing the risk of gastric cancer is still being debated. Therefore, we aimed to investigate whether long-term PPI use is associated with an increased risk of gastric cancer. We systematically searched the relevant literature in electronic databases, including PubMed, EMBASE, Scopus, and Web of Science. The search and collection of eligible studies was between 1 January 2000 and 1 July 2021. Two independent authors were responsible for the study selection process, and they considered only observational studies that compared the risk of gastric cancer with PPI treatment. We extracted relevant information from selected studies, and assessed the quality using the Newcastle−Ottawa scale (NOS). Finally, we calculated overall risk ratios (RRs) with 95% confidence intervals (CIs) of gastric cancer in the group receiving PPI therapy and the control group. Thirteen observational studies, comprising 10,557 gastric cancer participants, were included. Compared with patients who did not take PPIs, the pooled RR for developing gastric cancer in patients receiving PPIs was 1.80 (95% CI, 1.46−2.22, p < 0.001). The overall risk of gastric cancer also increased in patients with gastroesophageal reflux disease (GERD), H. pylori treatment, and various adjusted factors. The findings were also consistent across several sensitivity analyses. PPI use is associated with an increased risk of gastric cancer in patients compared with those with no PPI treatment. The findings of this updated study could be used in making clinical decisions between physicians and patients about the initiation and continuation of PPI therapy, especially in patients at high risk of gastric cancer. Additionally, large randomized controlled trials are needed to determine whether PPIs are associated with a higher risk of gastric cancer.

Acid Suppressive Drugs

Histamine H₂ receptor antagonists (H₂RAs) suppress gastric acid production by blocking H₂ receptors in parietal cells. Studies have shown that proton pump inhibitors (PPIs) are superior to H₂RAs as a treatment for acid-related disorders, such as peptic ulcer disease (PUD) and gastroesophageal reflux disease (GERD). PPIs reduce gastric acid production by irreversibly inhibiting the H⁺/K⁺ ATPase pump, and they also increase gastric emptying. Although PPIs have differing pharmacokinetic properties, each PPI is effective in managing GERD and PUDs. However, PPIs have some limitations, including short plasma half-lives, breakthrough symptoms (especially at night), meal-associated dosing, and concerns associated with long-term PPI use. Potassium-competitive acid blockers (P-CABs) provide more rapid and profound suppression of intragastric acidity than PPIs. P-CABs are non-inferior to lansoprazole in healing erosive esophagitis and peptic ulcers, and may also be effective in improving symptoms in patients with non-erosive reflux disease. Acid suppressive drugs are the most commonly used drugs in clinical practice, and it is necessary to understand the pharmacological properties and adverse effects of each drug.

Helicobacter pylori Treatment Regimens: A US Perspective

Helicobacter pylori infects nearly one-third of the US population. H pylori is a significant cause of gastroduodenal disease, including peptic ulcers and cancers. However, rising antibiotic resistance has complicated management of H pylori. This article provides a practical review of management strategies, including first-line empiric therapies and how to treat patients when prior therapies fail. Bismuthbased quadruple therapy remains the standard initial empiric regimen, although a rifabutin-based triple regimen is another approach for empiric therapy in the United States. Clarithromycin and levofloxacin therapies should be avoided except when treating a strain of known susceptibility. When therapies fail, resistance should be tested with molecular or culture-based methods. Knowing local resistance patterns and/or using practice-based eradication rates is important for devising logic-based clinical choices. Ultimately, shared decision-making, patient counseling, and careful attention to drug type and dosage are essential for refractory cases.

Population pharmacokinetics of esomeprazole in patients with preterm preeclampsia

Esomeprazole is a proton pump inhibitor being investigated for treatment of preeclampsia. Esomeprazole pharmacokinetics during pregnancy are unknown. We used data from 10 pregnant participants with preterm preeclampsia, and 49 non-pregnant participants to develop a population pharmacokinetic model of esomeprazole. A two-compartment model described the data well. In pregnant participants after single dose, clearance was 42.2% (14.9% - 61.6%) lower compared to non-pregnant, most likely due to inhibition of CYP2C19. In non-pregnant after repeated dosing, clearance was 54.9% (48.2% - 63.5%) lower in extensive metabolizers and bioavailability was 33% (10.0% - 52.0%) higher compared to single dosing, which could be due to autoinhibition of CYP2C19. During pregnancy, the CYP2C19 autoinhibition effect with repeated dosing is expected to lead to much lower increase in exposure compared to non-pregnant, since CYP2C19 is already inhibited due to pregnancy.

Population pharmacokinetics of omeprazole in obese and normal-weight adults

BACKGROUND

Obesity is related to many pathophysiological changes that may result in altered drug disposition. Omeprazole is the most common option utilized for acid-related disorders treatment; however, the pharmacokinetic (PK) and dosing recommendations for the obese patient population are lacking.

METHODS

Data from 40 healthy subjects with normal weights and data from 61 obese subjects were included. The subjects all received a single dose of 20 mg of omeprazole. Nonlinear mixed effects modeling were performed to characterize the effect of obesity on omeprazole PK.

RESULTS

A one-compartment model with twelve transit absorption compartments and linear elimination described the data best. A lower clearance was observed in the obese patient population than in the normal-weight subjects, which was opposite to the well-known allometric effect of body weight on drug clearance. Moreover, the CYP2C19 genotype was identified as a significant covariate for clearance.

CONCLUSION

Given the potential adverse events related to high exposure to proton pump inhibitors over time, obese patients may require a lower dose of omeprazole for long-term treatment. Further studies in obese individuals into other drugs metabolized by CYP2C19 are warranted, especially those with a narrow therapeutic window.

CLINICAL TRIAL REGISTRATION

www.chictr.org.cn identifier is ChiCTR2100046578; www.chinadrugtrials.org.cn identifier is CTR20190175.

Complex Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is the most prevalent gastrointestinal disorder posing diagnostic and therapeutic challenges. Diagnosis should be objectively defined with endoscopy and pH testing, while novel metrics may augment diagnosis for inconclusive GERD cases, including the postreflux swallow-induced peristaltic wave index and esophageal mucosal impedance. Conditions that overlap with or mimic GERD should be considered such as achalasia, rumination, and eosinophilic esophagitis. Genetic testing for proton pump inhibitor metabolism is an option for precision therapy in complex persistent GERD. Proton pump inhibitor refractory GERD may require medical, surgical, or endoscopic therapies. The presence of GERD should be objectively evaluated in achalasia patients treated with peroral endoscopic myotomy, and further studies are needed to determine timing of this evaluation. Patients with scleroderma are at a high risk for GERD owing to abnormal esophageal motility and should be managed with aggressive medical therapy and lifestyle changes given the high prevalence of esophagitis and Barrett's esophagus in this population. Further studies are needed to understand the complex mechanisms of GERD in idiopathic pulmonary fibrosis and lung transplantation.

Mitigation of Gastric Damage Using Cinnamomum cassia Extract: Network Pharmacological Analysis of Active Compounds and Protection Effects in Rats

Gastritis is a common disease worldwide that is caused by various causes such as eating habits, smoking, severe stress, and heavy drinking, as well as Helicobacter pylori infections and non-steroidal anti-inflammatory drugs. Cinnamomum cassia is a tropical aromatic evergreen tree commonly used as a natural medicine in Asia and as a functional food ingredient. Studies have reported this species' anti-obesity, anti-diabetic, and cardiovascular disease suppression effects. We evaluated the potential effects of C. cassia using non-steroidal anti-inflammatory drugs (NSAIDs), ethanol (EtOH), and ethanol/hydrochloric acid (HCl)-induced gastric mucosal injury models. C. cassia extracts reduced the area of gastric mucosa injury caused by indomethacin, NSAID, EtOH, and EtOH/HCl. We also applied a network pharmacology-based approach to identify the active compounds, potential targets, and pharmacological mechanisms of C. cassia against gastritis. Through a network pharmacology analysis, 10 key components were predicted as anti-gastritis effect-related compounds of C. cassia among 51 expected active compounds. The NF-κB signaling pathway, a widely known inflammatory response mechanism, comprised a major signaling pathway within the network pharmacology analysis. These results suggest that the anti-gastritis activities of C. cassia may be induced via the anti-inflammatory effects of key components, which suppress the inflammation-related genes and signaling pathways identified in this study.

Evaluation of the relationship between polymorphisms in CYP2C19 and the single-dose pharmacokinetics of omeprazole in healthy Chinese volunteers: A multicenter study

The aim of this study was to evaluate the relationship between polymorphisms in CYP2C19 and the single‐dose pharmacokinetics (PKs) of omeprazole in healthy Chinese volunteers. A 20 mg single dose of omeprazole (Losec) enteric‐coated capsules or tablets was orally administered to 656 healthy subjects from eight subcenters. The polymorphic alleles of CYP2C19*2, *3, and *17 were determined by Sanger sequencing and Agena mass array. Plasma concentrations of omeprazole were determined by high‐performance liquid‐chromatography tandem mass spectrometry. PK parameters of area under the concentration versus time curve (AUC)_0‐t, AUC from zero to infinity (AUC_0‐∞), maximum plasma concentration (C_max), and terminal half‐life (t_1/2) were significantly influenced by CYP2C19 phenotype (all p < 0.001) and diplotype (all p < 0.001), and the same results were obtained in the subgroup analysis of the effects of diet and dosage form. The polymorphisms of CYP2C19*2(rs4244285; all PK parameters p < 0.001) and *3(rs4986893; p_Cmax = 0.020, and the p values of other PK parameters were less than 0.001) were significantly associated with the PKs of omeprazole. For CYP2C19*17 (rs12248560), only t_1/2 showed a significant correlation (p = 0.032), whereas other PK parameters did not. The present study demonstrated that the Pks of omeprazole is greatly influenced by CYP2C19.

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.

Analysis of the Guiding Role of CYP2C19 Gene Combined With Platelet Function Detection in Antiplatelet Therapy in Patients With Complex Coronary Artery Disease After PCI

Objective

To explore the influence of CYP2C19 gene combined with platelet function test on clinical prognosis of patients with complex coronary artery disease receiving antiplatelet therapy after PCI.

Methods

A total of 200 patients undergoing PCI in our hospital due to complex coronary artery disease from February 2019 to February 2021 were selected and divided into the control group and the observation group according to whether CYP2C19 gene detection was performed. The control group was treated with dual antiplatelet therapy of classical aspirin combined with clopidogrel, and the observation group was treated with individual antiplatelet therapy. The patients in the two groups were followed up for 1 year after PCI, and their quality of life was assessed using the Seattle Angina Questionnaire (SAQ score). The occurrence of major adverse cardiovascular events (MACE) during the follow-up period was also recorded.

Results

The incidence of total MACE events in the observation group was slightly less than that in the control group, and the difference was statistically significant (P = 0.040). In particular, the observation group was superior to the control group in reducing the readmission rate of recurrent unstable angina pectoris, and the difference was statistically significant (P = 0.023). The location of coronary culprit lesions with recurrent ischemic events was commonly seen in non-interventional target lesions (interventional/non-interventional target sites: 12.9%: 77.1%). The SAQ score in the observation group was larger than that in the control group, and the difference was statistically significant (P = 0.012). There was no statistical difference in the incidence of major bleeding between the two groups (P = 0.352).

Conclusion

Using CYP2C19 genotype combined with platelet function test to guide individualized antiplatelet therapy after complex coronary artery PCI is beneficial to reducing ischemic events in a short period (1 year), mainly due to reducing the risk of readmission for recurrent unstable angina pectoris, and improving the quality of daily life of patients without increasing the risk of massive hemorrhage, which can improve clinical prognosis.

Association of CYP2C19 polymorphism with proton pump inhibitors effectiveness and with fractures in real‐life: retrospective cohort study

Symptom refractoriness of patients treated with proton pump inhibitors (PPIs) might be explained by polymorphism in CYP2C19. This is a retrospective cohort study in which we used the computerized database of Clalit Health Services to compose a cohort from cancer case‐control studies’ participants that had been genotyped, and that have been dispensed PPI (January 1, 2002 to November 10, 2020). We retrieved demographic and clinical variables on date of PPI initiation (cohort entry), and studies’ questionnaires‐reported consumption of foods/beverages known to increase peptic‐related symptoms. Primary outcome was an abdominal pain diagnosis; secondary outcome was a composite of abdominal pain, visit to a gastroenterology clinic, change to another PPI, PPI dose increase, or metoclopramide prescription, reflecting symptoms persistence/recurrence; in a 2‐year follow‐up. We also evaluated the association between genetic groups and hip/wrist/spine fractures, in a long‐term follow‐up. Of 3,326 PPI initiators, there were 66 (2.0%), 739 (22.2%), 1394 (41.9%), 947 (28.5%), and 180 (5.4%) CYP2C19 poor, intermediate, normal, rapid, and ultra‐rapid metabolizers, respectively. Being a poor metabolizer was associated with lower risk for the primary outcome, hazard ratio (HR) = 0.50 (95% confidence interval (CI) 0.27–0.91), HR = 0.52 (95% CI 0.28–0.94); and for the secondary outcome, HR = 0.57 (95% CI 0.38–0.86), HR = 0.58 (95% CI 0.39–0.87), in univariate and multivariable cox regression analyses, respectively. In long‐term follow‐up with 20,142 person‐years of follow‐up: 7.6% (5 cases) within the poor metabolizers group, and 11.6%, 12.9%, 12.8%, and 11.1% in the normal, intermediate, rapid, and ultra‐rapid metabolizers groups, respectively, had a new fracture (nonsignificant). We conclude that CYP2C19 poor metabolizer status is associated with higher effectiveness of PPIs, and is not associated with higher risk for fractures.

Proton Pump Inhibitor Therapy for Eosinophilic Esophagitis: History, Mechanisms, Efficacy, and Future Directions

Over the past decade, the role of proton pump inhibitor (PPI) medication has evolved from a diagnostic tool for Eosinophilic Esophagitis (EoE), by excluding patients with PPI responsive esophageal eosinophilia (PPI-REE), to a therapy for EoE. This transition resulted from the Updated International Consensus Diagnostic Criteria for Eosinophilic Esophagitis: Proceedings of the Appraisal of Guidelines for Research and Evaluation II (AGREE) Conference to support PPI therapy for EoE in children and adults. Additional recent advances have suggested a role for genetic variations that might impact response to PPI therapy for EoE. This review article will explore a brief background of EoE, the evolution of PPI therapy for EoE and its proposed mechanisms, efficacy and safety in children and adults, and considerations for future PPI precision medicine in patients with EoE.

Eosinophil-Derived Neurotoxin Predicts Response to Proton-Pump Inhibitor Treatment in Pediatric Eosinophilic Esophagitis

OBJECTIVES

There are no tests or patient factors to help predict the best treatment approach for a patient with eosinophilic esophagitis (EoE). The prevalence of proton-pump inhibitor (PPI) responsive EoE in children ranges from 30% to 71% with multiple studies showing similar characteristics in responders and nonresponders. Eosinophil-derived neurotoxin (EDN), an eosinophilic granule protein, measured in esophageal brushing has been shown to be a viable measure of disease activity in EoE. Our aim is to determine if EDN can help predict response to PPI in pediatric patients with EoE.

METHODS

We conducted a prospective cross-sectional study to compare EDN between PPI-responsive and PPI-nonresponsive EoE subjects from 2018 through 2020. Enrolled patients with active EoE were treated with high-dose PPI and underwent repeat endoscopy to determine PPI-responsiveness. EDN was measured at baseline endoscopy, before any treatment, and at follow up endoscopy, after PPI therapy. Subjects were divided into PPI-responsive and nonresponsive groups. EDN, endoscopic reference score (EREFS), and peak eosinophilic count (PEC) were compared.

RESULTS

Fifteen out of the 36 enrolled subjects with EoE (age range 2-18 years, 73.3% male) were PPI-responsive and 21 (age range 2-19 years, 95.2% male) were PPI-nonresponsive. EDN concentration was significantly higher in the PPI-nonresponsive group than in the PPI-responsive group (219.1 ± 229 mcg/mL vs 75.7 ± 60 mcg/mL, respectively, P = 0.036). There was no difference between the two groups in EREFS (P = 0.55) or PEC (P = 0.15).

CONCLUSIONS

EDN measured in esophageal epithelial samples obtained by brushing during endoscopy may predict PPI-responsiveness in children and young adults with EoE.

Pharmacogenomics fail to explain proton pump inhibitor refractory esophagitis in pediatric esophageal atresia

BACKGROUND

Esophagitis is prevalent in patients with esophageal dysmotility despite acid suppression, likely related to poor esophageal clearance. Esophageal atresia (EA) is a classic model of dysmotility where this observation holds true. In adult non-dysmotility populations, failure of esophagitis to respond to proton pump inhibitors (PPI) has been linked to variants in CYP2C19 that influence the activity of the encoded enzyme. It is unknown if CYP2C19 metabolizer phenotype contributes to PPI-refractory, non-allergic esophagitis in EA.

METHODS

We performed a cross-sectional study of 314 children with (N = 188) and without (N = 126) EA who were on PPI therapy at the time of endoscopy to evaluate for possible gastroesophageal reflux disease. Patients with eosinophilic esophagitis and/or fundoplication were excluded. Clinical and histology data were collected. Genomic DNA from biopsy samples was genotyped for polymorphisms in CYP2C19.

RESULTS

CYP2C19 metabolizer phenotypes were not associated with presence or severity of esophagitis (P = 0.994). In a multivariate logistic regression adjusted for potential confounders, EA was the strongest and only significant predictor of esophagitis (odds ratio 2.72, P = 0.023). Using negative binomial regression, we found that CYP2C19 phenotype was not a significant predictor of eosinophil count in children with PPI-refractory esophagitis.

CONCLUSIONS

Patients with EA are significantly more likely to experience PPI-refractory, non-allergic esophagitis than controls regardless of CYP2C19 metabolizer phenotype, suggesting that factors other than CYP2C19 genetics, including dysmotility, are the primary drivers of esophagitis in EA. CYP2C19 genotype failed to predict PPI-refractory, non-allergic esophagitis in both EA and non-EA children.