Review article: the clinical pharmacology of proton pump inhibitors

Diagnostic Accuracy of EndoFaster® and Narrow-Band Imaging Endoscopy in Patients with Impaired Gastric Acid Secretion: A Real-Time Prospective Study

BACKGROUND

EndoFaster® analyzes gastric juice in real time during gastroscopy allowing the detection of hypo-achlorhydric conditions, like corpus atrophic gastritis. Narrow-band imaging (NBI) endoscopy allows to accurately detect and perform target biopsies in areas of intestinal metaplasia, a histological change often associated to corpus atrophic gastritis.

AIMS

To compare the diagnostic accuracy of EndoFaster® with histological evaluation for corpus atrophic gastritis through high-resolution (HR) NBI targeted biopsies.

METHODS

Prospective study on consecutive adult patients undergoing gastroscopy between April and November 2018. Patients in therapy with proton pump inhibitors, previous gastric surgery, and/or known gastric neoplasia were excluded. At the beginning of gastroscopy, gastric juice was aspirated and analyzed by EndoFaster® in 15 seconds. Endoscopists were blinded to the report of EndoFaster®. Evaluation of gastric mucosa in HR-white light was firstly performed, then with HR-NBI allowing to perform targeted biopsies on areas suspected for intestinal metaplasia; otherwise, biopsies were performed according to the updated Sydney System protocol and sent for histopathological evaluation.

RESULTS

Overall, 124 patients were included [64% F; 56 (18-85) years]. Corpus atrophic gastritis was present in 41.9% of patients. EndoFaster® showed an accuracy for corpus atrophic gastritis diagnosis, compared to histopathological evaluation as gold standard, of 87.1% and a sensitivity, specificity, PPV, and NPV of 78.8%, 93.1%, 89.1%, and 85.9%, respectively. pH showed a positive correlation with the severity score of atrophy (r = 0.67, 95% CI: 0.73-0.81, and p < 0.0001). EndoFaster® allowed to diagnose corpus atrophic gastritis in 3.7% of patients negative to NBI (corpus atrophic gastritis without intestinal metaplasia).

CONCLUSION

EndoFaster® seems a promising tool to diagnose corpus atrophic gastritis. The evaluation of hypo-achlorhydria during gastroscopy can address bioptic sampling in corpus atrophic gastritis patients without intestinal metaplasia.

Long-term use of proton pump inhibitors as a risk factor for various adverse manifestations

The long-term use of proton pump inhibitors (PPIs) can lead to increased gastric pH, hypochlorhydria and in some cases to achlorhydria when compared to other acid-suppressing agents like histamine-2 (H2) receptor blockers and antacids. These consequences by the use of long-term PPIs may lead to significant vitamin (B₁₂ and C) and mineral (iron, calcium and magnesium) deficiencies which needs gastric acid for their absorption and bioavailability. Long-term use of PPIs by the pregnant patients may impose a potential risk of congenital malformations. Various studies have recommended the life style modifications and antacid use as first choice among pregnant womens by preserving PPIs (omeprazole as a safe choice of PPI) for severe conditions of gastroesophageal reflux disease. The long-term acid suppression by PPIs can also lead to enteric, respiratory and urinary tract infections. The hypochlorhydria by chronic PPIs use may induce hypergastrinemia, which ultimately mediates the gastric polyps, gastric carcinoids and gastric cancer. The concomitant use of PPIs with antiplatelet drugs like clopidogrel can impose the patients to major adverse cardiac events. This review has enlisted the comprehensive information regarding the adverse effects induced by long-term use of PPIs and their possible relations. Considerable studies like case-control, randomized trials, cohort studies and meta-analysis were reported in supporting these adverse effects. The clinicians and patients should be cautious about these effects so that they can avoid the serious outcomes. PPIs should be avoided for long-term use mainly in older adults unless there is a proper indication.

Proton Pump Inhibitor-Induced Galactorrhea in a Kidney Transplant Recipient: A Friend or Foe?

Over the last decades, proton pump inhibitors (PPIs) have been widely used as the mainstay for treatment and prevention of gastrointestinal side effects, gastroesophageal reflux, and peptic ulcer disease. However, their safety profile has come into question recently after reports relating them to several side effects as well as kidney disease. Omeprazole, one of the mainly used PPIs, is almost entirely metabolized by the liver but the resulting metabolites are renally excreted. These metabolites may inhibit cytochrome P450 2C19 (CYP2C19) and cytochrome P450 3A4 (CYP3A4) reversibly, but as recent evidence suggests, they may also be involved in causing kidney disease. In the setting of renal dysfunction, these metabolites will not be excreted from the body and will accumulate further causing kidney damage and inhibiting CYP enzymes to a greater extent. Abnormally high serum prolactin levels leading to galactorrhea may be the result of such an accumulation. To our knowledge, there have been only three previously reported cases of PPI-induced galactorrhea in the literature but none in a kidney transplant recipient. In patients with established kidney disease and reduced glomerular filtration rate like kidney transplant recipients, the use of PPIs should be thoroughly assessed. Reduced clearance of their metabolites may lead to progression of the kidney disease and lead to more unwanted side effects. We present a case of a female kidney transplant recipient with worsening allograft function who presented with sudden galactorrhea and hyperprolactinemia while on a high-dose omeprazole for gastroesophageal reflux disease.

A Prospective Randomized Clinical Trial of Combination Therapy with Proton Pump Inhibitors and Mucolytics in Patients with Laryngopharyngeal Reflux

OBJECTIVES

To identify whether combination therapy with mucolytics and proton pump inhibitors (PPIs) leads to faster and more effective symptomatic relief in patients with laryngopharyngeal reflux (LPR).

METHODS

Patients diagnosed as LPR with a reflux symptom index (RSI) ≥ 13 and a reflux finding score (RFS) ≥ 7 were enrolled in this prospective study. Patients were randomly allocated to control (PPI only) or experimental (PPI + mucolytics) groups and changes in RSI and RFS values were assessed at 1- and 3-month follow-up.

RESULTS

One hundred sixteen patients were randomly allocated into either the control group (n = 59) or the experimental group (n = 57). The RSI and RFS scores significantly decreased in both groups (all P < .001) after 1 month of treatment; however, there was no significant difference in RSI change between groups (P = .223). After 3 months of treatment, there remained no significant difference in RSI change between groups (P = .592).

CONCLUSIONS

Combination therapy with mucolytics and PPI compared to PPI alone did not lead to faster or more effective symptomatic relief in LPR patients.

Effect of a Preoperative Proton Pump Inhibitor and Gastroesophageal Reflux Disease on Postoperative Nausea and Vomiting

Postoperative nausea and vomiting (PONV) are common complications after anesthesia, but no study has considered the effects of a proton pump inhibitor (PPI) and gastroesophageal reflux disease (GERD) on PONV at the same time. Thus, we investigated the effects of a PPI and GERD on PONV. Patients aged ≥18 years who underwent general anesthesia between 2010 and 2019 were enrolled. In total, 202,439 patients were included and 21,361 In a multivariate analysis, the OR for PONV was higher in subjects with GERD (OR, 1.157; 95% CI, 1.032-1.298; p = 0.012). The OR was lower for subjects with taking a PPI (OR, 0.890; 95% CI, 0.832-0.953; p < 0.0001). In patients without GERD, the incidence of PONV was lower when lansoprazole (OR, 0.801; 95% CI, 0.718-0.894; p < 0.0001), pantoprazole (OR, 0.856; 95% CI, 0.748-0.980; p = 0.025) and ilaprazole (OR, 0.391; 95% CI, 0.158-0.966; p = 0.042) were taken. However, in GERD patients, all PPIs did not show reducing the incidence of PONV. Taken together, the results show that a lansoprazole, pantoprazole, and ilaprazole reduced PONV in patients without GERD, and PPI could not reduce PONV in patients with GERD.

Selective Targeting of Virus Replication by Proton Pump Inhibitors

Two proton pump inhibitors, tenatoprazole and esomeprazole, were previously shown to inhibit HIV-1 egress by blocking the interaction between Tsg101, a member of the ESCRT-I complex, and ubiquitin. Here, we deepen our understanding of prazole budding inhibition by studying a range of viruses in the presence of tenatoprazole. Furthermore, we investigate the relationship between the chemistry of prodrug activation and HIV-1 inhibition for diverse prazoles currently on the market. We report that tenatoprazole is capable of inhibiting the replication of members of the enveloped filo, alpha, and herpes virus families but not the flavivirus group and not the non-enveloped poliovirus. Another key finding is that prazole prodrugs must be activated inside the cell, while their rate of activation in vitro correlated to their efficacy in cells. Our study lays the groundwork for future efforts to repurpose prazole-based compounds as antivirals that are both broad-spectrum and selective in nature.

Synthesis and discovery of triazolo-pyridazine-6-yl-substituted piperazines as effective anti-diabetic drugs; evaluated over dipeptidyl peptidase-4 inhibition mechanism and insulinotropic activities

A family of 12 triazolo-pyridazine-6-yl-substituted piperazines (5a-l) was synthesized and evaluated for their Dipeptidyl peptidase-4 (DPP-4) inhibition potentials in order to develop them as anti-diabetic medications. In the two-step synthesis process, 6-chloro-3-(m-tolyl)-[1,2,4]triazolo[4,3-b]pyridazine was synthesized with one-pot mode using pyridine, 3,6-dichloropyridazine 5-(3-methyl-phenyl)tetrazole in toluene. Conjugating corresponding 2° amines with 6-chloro-3-(m-tolyl)-[1,2,4]triazolo[4,3-b]pyridazine afforded the target triazolo-pyridazine-6-yl-substituted piperazines (5a-l). DPP-4 inhibition potential of these compounds was testified in silico and in nitro along with their insulinotropic activities in 832/13 INS-1 cells. H₂O₂ radical scavenging assay and MTT assay were conducted to assess the antioxidant and cytotoxicity of these compounds respectively. Molecular docking and ELISA based enzyme inhibition assay results revealed the strong inhibition potential of the target compounds. MTT assay results indicated a maximum dose of 2.5 nM (IC₅₀ 1.25 nM) could be used and above this level vital for the cells. Compounds 5a, 5c, 5g and 5i were found with excellent antioxidant and insulinotropic activity up to 99%.

Phase III, randomised, double-blind, multicentre study to evaluate the efficacy and safety of vonoprazan compared with lansoprazole in Asian patients with erosive oesophagitis

OBJECTIVE

To establish the non-inferior efficacy of vonoprazan versus lansoprazole in the treatment of Asian patients with erosive oesophagitis (EO).

DESIGN

In this phase III, double-blind, multicentre study, patients with endoscopically confirmed EO were randomised 1:1 to receive vonoprazan 20 mg or lansoprazole 30 mg, once daily for up to 8 weeks. The primary endpoint was EO healing rate at 8 weeks. The secondary endpoints were EO healing rates at 2 and 4 weeks. Safety endpoints included treatment-emergent adverse events (TEAEs).

RESULTS

In the vonoprazan (n=238) and lansoprazole (n=230) arms, 8-week EO healing rates were 92.4% and 91.3%, respectively (difference 1.1% (95% CI -3.822% to 6.087%)). The respective 2-week EO healing rates were 75.0% and 67.8% (difference 7.2% (95% CI -1.054% to 15.371%)), and the respective 4-week EO healing rates were 85.3% and 83.5% (difference 1.8% (95% CI -4.763% to 8.395%)). In patients with baseline Los Angeles classification grade C/D, 2-week, 4-week and 8-week EO healing rates were higher with vonoprazan versus lansoprazole (2 weeks: 62.2% vs 51.5%, difference 10.6% (95% CI -5.708% to 27.002%); 4 weeks: 73.3% vs 67.2%, difference 6.2% (95% CI -8.884 to 21.223); and 8 weeks: 84.0% vs 80.6%, difference 3.4% (95% CI -9.187% to 15.993%)). Overall, EO healing rates appeared higher with vonoprazan versus lansoprazole. TEAE rates were 38.1% and 36.6% in the vonoprazan and lansoprazole group, respectively.

CONCLUSION

Our findings demonstrate the non-inferior efficacy of vonoprazan versus lansoprazole in terms of EO healing rate at 8 weeks in this population. Safety outcomes were similar in the two treatment arms.

TRIAL REGISTRATION NUMBER

NCT02388724.

Comparison of Oral versus Intravenous Proton Pump Inhibitors in Preventing Re-bleeding from Peptic Ulcer after Successful Endoscopic Therapy

Introduction Perforation, obstruction, and bleeding remain the most frequently encountered complications of peptic ulcer disease (PUD). Bleeding may be in the form of hematemesis or melena. The treatment of choice in patients with a bleeding peptic ulcer is endoscopic ligation to maintain the hemostatic balance followed by the administration of proton pump inhibitors (PPIs). This study focuses on the evaluation and comparison of intravenous (IV) and oral PPIs in terms of prevention of re-bleeding after successful endoscopy for peptic ulcers. Methods A prospective, comparative study was conducted in a tertiary care hospital in Pakistan from January 1, 2018 to June 30, 2019. The trial included known cases of PUD admitted with active upper gastrointestinal bleeding (UGIB). They were randomly divided into two groups: one received oral pantoprazole and the other was administered IV pantoprazole. The outcomes for both groups were compared. Data was entered and analyzed using Statistical Package for the Social Sciences (SPSS) software version 23.0 (IBM, Armonk, NY) Results There were 96 (48%) patients in the IV pantoprazole group and 104 (52%) in the oral group. From 24 hours after the medication onwards, the IV pantoprazole group showed a significant improvement in hemoglobin (Hb) levels (p: 0.01); the group also showed improvement in supine systolic BP at 48 hours (p: 0.04) and in diastolic BP at both 12 and 48 hours as compared to the oral pantoprazole group (p: 0.05). The mean duration of hospital stay, need for blood transfusion and repeat endoscopy, re-bleeding, and mortality rates were similar for both groups (p: >0.05). Conclusion We could not find any statistically significant difference between oral and IV routes of pantoprazole administration in the prevention of rebleeding when used after successful therapeutic endoscopy in patients with bleeding PUDs.

Drug resistance in Giardia: Mechanisms and alternative treatments for Giardiasis

The use of chemotherapeutic drugs is the main resource against clinical giardiasis due to the lack of approved vaccines. Resistance of G. duodenalis to the most used drugs to treat giardiasis, metronidazole and albendazole, is a clinical issue of growing concern and yet unknown impact, respectively. In the search of new drugs, the completion of the Giardia genome project and the use of biochemical, molecular and bioinformatics tools allowed the identification of ligands/inhibitors for about one tenth of ≈150 potential drug targets in this parasite. Further, the synthesis of second generation nitroimidazoles and benzimidazoles along with high-throughput technologies have allowed not only to define overall mechanisms of resistance to metronidazole but to screen libraries of repurposed drugs and new pharmacophores, thereby increasing the known arsenal of anti-giardial compounds to some hundreds, with most demonstrating activity against metronidazole or albendazole-resistant Giardia. In particular, cysteine-modifying agents which include omeprazole, disulfiram, allicin and auranofin outstand due to their pleiotropic activity based on the extensive repertoire of thiol-containing proteins and the microaerophilic metabolism of this parasite. Other promising agents derived from higher organisms including phytochemicals, lactoferrin and propolis as well as probiotic bacteria/fungi have also demonstrated significant potential for therapeutic and prophylactic purposes in giardiasis. In this context the present chapter offers a comprehensive review of the current knowledge, including commonly prescribed drugs, causes of therapeutic failures, drug resistance mechanisms, strategies for the discovery of new agents and alternative drug therapies.

Proton Pump Inhibitors and Radiofrequency Ablation for Treatment of Barrett's Esophagus

Gastroesophageal Reflux Disease (GERD) is characterized by acid and bile reflux in the distal oesophagus, and this may cause the development of reflux esophagitis and Barrett's oesophagus (BE). The natural histological course of untreated BE is non-dysplastic or benign BE (ND), then lowgrade (LGD) and High-Grade Dysplastic (HGD) BE, with the expected increase in malignancy transfer to oesophagal adenocarcinoma (EAC). The gold standard for BE diagnostics involves high-resolution white-light endoscopy, followed by uniform endoscopy findings description (Prague classification) with biopsy performance according to Seattle protocol. The medical treatment of GERD and BE includes the use of proton pump inhibitors (PPIs) regarding symptoms control. It is noteworthy that long-term use of PPIs increases gastrin level, which can contribute to transfer from BE to EAC, as a result of its effects on the proliferation of BE epithelium. Endoscopy treatment includes a wide range of resection and ablative techniques, such as radio-frequency ablation (RFA), often concomitantly used in everyday endoscopy practice (multimodal therapy). RFA promotes mucosal necrosis of treated oesophagal region via high-frequency energy. Laparoscopic surgery, partial or total fundoplication, is reserved for PPIs and endoscopy indolent patients or in those with progressive disease. This review aims to explain distinct effects of PPIs and RFA modalities, illuminate certain aspects of molecular mechanisms involved, as well as the effects of their concomitant use regarding the treatment of BE and prevention of its transfer to EAC.

Drug repurposing for anticancer therapies. A lesson from proton pump inhibitors

Introduction: Worldwide, the annual expenditure on anticancer drugs is grossly calculated to be in the order of US$100 billion, and is expected to escalate up to $150 billion by 2020. It is evident that the vast majority of the most recently devised anticancer drugs are unaffordable in economically developing nations, frequently resulting in subpar therapies. In this complex medical and economic scenario, the repurposing of older drugs for anticancer therapies becomes a necessity. The repurposing of antiacid drugs such as the proton pump inhibitors as antitumoral agents and chemosensitizers is probably one of the most recent and promising phenomenon in oncology.Areas covered: Important research articles and patents focusing on proton pump inhibitors as a potential class of therapeutics, published between the period of 2006-2019, have been covered. This review mainly focuses on the therapeutic applications, as direct anticancer agents as well as modifiers of the tumor microenvironment and modulator of chemoresistance.Expert opinion: PPIs have significant anticancer applications and are proving to be safe, effective and inexpensive. Here the authors review the current knowledge regarding the influence of PPIs on the efficacy and safety of cancer chemotherapeutics through the regulation of targets other than the H⁺/K⁺-ATPase.

A Novel Zebrafish Model of Metastasis Identifies the HSD11β1 Inhibitor Adrenosterone as a Suppressor of Epithelial-Mesenchymal Transition and Metastatic Dissemination

Metastasis of cancer cells is multi-step process and dissemination is an initial step. Here we report a tamoxifen-controllable Twist1a-ER^T2 transgenic zebrafish line as a new animal model for metastasis research, and demonstrate that this model can serve as a novel platform for discovery of antimetastasis drugs targeting metastatic dissemination of cancer cells. By crossing Twist1a-ER^T2 with xmrk (a homolog of hyperactive form of EGFR) transgenic zebrafish, which develops hepatocellular carcinoma, approximately 80% of the double transgenic zebrafish showed spontaneous cell dissemination of mCherry-labeled hepatocytes from the liver to the entire abdomen region and the tail region. The dissemination is accomplished in 5 days through induction of an epithelial-to-mesenchymal transition. Using this model, we conducted in vivo drug screening and identified three hit drugs. One of them, adrenosterone, an inhibitor for hydroxysteroid (11-beta) dehydrogenase 1 (HSD11β1), has a suppressor effect on cell dissemination in this model. Pharmacologic and genetic inhibition of HSD11β1 suppressed metastatic dissemination of highly metastatic human cell lines in a zebrafish xenotransplantation model. Through downregulation of Snail and Slug, adrenosterone-treated cells recovered expression of E-cadherin and other epithelial markers and lost partial expression of mesenchymal markers compared with vehicle-treated cells. Taken together, our model offers a useful platform for the discovery of antimetastasis drugs targeting metastatic dissemination of cancer cells. IMPLICATIONS: This study describes a transgenic zebrafish model for liver tumor metastasis and it has been successfully used for identification of some drugs to inhibit metastatic dissemination of human cancer cells.

Regulation of adipocyte differentiation and metabolism by lansoprazole

AIMS

Lansoprazole (LPZ) is one of the most commonly prescribed drugs for treatment of acid-related diseases, and it is increasingly recognized for its potential application as an anti-diabetic therapy. Although LPZ target tissues remain poorly understood, possible sites of action include adipose tissue. In this study, we assessed effects of LPZ on adipocyte differentiation and function by using 3T3-L1 preadipocytes and HFD-induced obesity mice as an in vitro and in vivo model, respectively.

MAIN METHODS

Oil red O staining and intracellular triacylglycerol content were used to determine lipid accumulation. Glucose uptake was performed to measure mature adipocyte function. Expression of adipocyte genes was determined by qRT-PCR and immunoblotting.

KEY FINDINGS

LPZ has dual effects on differentiation of 3T3-L1 cells. At low concentrations, LPZ enhanced adipocyte differentiation via induction of PPARγ and C/EBPα, two master adipogenic transcription factors, as well as lipogenic proteins, ACC1 and FASN. Increasing of adipocyte number subsequently increased basal and insulin-stimulated glucose uptake, and expression of Glut4 mRNA. Conversely, high concentrations of LPZ strongly inhibited differentiation and expression of PPARγ and C/EBPα, and maintained expression of preadipocytes markers, β-catenin and Pref-1. Inhibition of adipogenesis by LPZ reduced mature adipocyte number, Glut4 mRNA expression and insulin-stimulated glucose uptake. In addition, treatment with LPZ at 200 mg/kg significantly reduced body weight gain and total fat mass in HFD-induced obese mice.

SIGNIFICANCE

These results indicate that effects of LPZ on adipocyte differentiation are dependent on concentration and are correlated with PPARγ and C/EBPα.

Targeted covalent inhibitors of MDM2 using electrophile-bearing stapled peptides

Herein, we describe the development of a novel staple with an electrophilic warhead to enable the generation of stapled peptide covalent inhibitors of the p53-MDM2 protein-protein interaction (PPI). The peptide developed showed complete and selective covalent binding resulting in potent inhibition of p53-MDM2 PPI.

In search of the grail: A race for acid suppression

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

Intragastric pH effect of 20mg of levo-pantoprazole versus 40mg of racemic pantoprazole the first seven days of treatment in patients with gastroesophageal reflux disease

INTRODUCTION/AIM

Levo-pantoprazole, the S-enantiomer of pantoprazole, is a proton pump inhibitor that has been shown in animal studies to be faster and stronger than its racemic formulation. There are no studies on humans and therefore our aim was to evaluate the effects of levo-pantoprazole versus racemic pantoprazole on intragastric pH.

MATERIALS AND METHODS

A randomized controlled study was conducted on patients with erosive gastroesophageal reflux disease that were given 20mg of levo-pantoprazole (n = 15) versus 40mg of racemic pantoprazole (n = 15) for 7 days. Baseline and end-of-treatment symptom evaluation and intragastric pH measurement were carried out.

RESULTS

There were no differences between the groups in the baseline evaluations. From 40 to 115min after the first dose of levo-pantoprazole, the mean intragastric pH was higher, compared with that of racemic pantoprazole (p < 0.05). After one week, levo-pantoprazole and racemic pantoprazole significantly reduced intragastric acid production and its esophageal exposure (p < 0.05). Even though there was no statistically significant difference, a larger number of patients that received levo-pantoprazole stated that their heartburn improved within the first 3 days.

CONCLUSIONS

The S-enantiomer of pantoprazole (levo-pantoprazole) had a faster and stronger effect with respect to acid suppression, compared with its racemic formulation. Although the effect on symptoms was faster with levo-pantoprazole, occurring within the first days of treatment, it was equivalent to that of the racemate at one week of treatment.

Identification and structural characterization of the stress degradation products of omeprazole using Q-TOF-LC-ESI-MS/MS and NMR experiments: evaluation of the toxicity of the degradation products

Omeprazole (OMP), a prototype proton pump inhibitor used for the treatment of peptic ulcers and gastroesophageal reflux disease (GERD), was subjected to forced degradation studies as per ICH guidelines Q1A (R2).

Increase in cetuximab-induced skin rash and hypomagnesemia in patients receiving concomitant treatment with proton pump inhibitors (PPIs): a possible drug interaction?

INTRODUCTION

In a previous study, we found that co-administration of proton pump inhibitors (PPIs) with cetuximab was associated with increased skin toxicity. Both these drugs can induce hypomagnesemia. The aim of this study was to retrospectively explore the possible influence of PPI drugs on cetuximab skin toxicity and the potential synergistic effect of hypomagnesemia.

PATIENTS AND METHODS

The files of all eligible patients treated with cetuximab during 2015-2016 with metastatic colorectal carcinoma (mCRC) or head and neck (H&N) carcinoma were reviewed. The concomitant use of PPIs was defined if a drug belonging to that class was included in the patient's chronic medications list.

RESULTS

One hundred eighteen patients (61 with H&N carcinoma, 57 with mCRC) were included in the study, and 58 of the 118 patients received PPIs concomitantly with cetuximab. Skin toxicity of any grade was reported in 33/58 (56.9%) patients on PPIs compared with 22/60 (36.7%) patients (p = 0.08) with grade 3-4 in 19/58 (32.8%) and 2/60 (3.3%), respectively (p = 0.001). Hypomagnesemia (Mg serum level < 1.2 mg/dL) was reported in 14/58 (25.9%) PPI-treated patients, compared with 5/60 (10.4%) patients not on PPIs (p = 0.08). Grade 3-4 skin toxicity or hypomagnesemia (Mg < 0.9 mg/dL) was reported in 23/58 (39.7%) patients on concomitant treatment with PPIs, compared with 3/60 (5%) patients not on PPIs (p = 0.001).

CONCLUSIONS

Both the rate and the severity of cetuximab-induced skin toxicity and hypomagnesemia were increased by chronic concomitant administration of PPIs. A prospective study is needed to confirm the possible interaction between cetuximab and PPIs.

Pharmacological treatments for functional nausea and functional dyspepsia in children: a systematic review

INTRODUCTION

Chronic idiopathic nausea (CIN) and functional dyspepsia (FD) cause considerable strain on many children's lives and their families. Areas covered: This study aims to systematically assess the evidence on efficacy and safety of pharmacological treatments for CIN or FD in children. CENTRAL, EMBASE, and Medline were searched for Randomized Controlled Trials (RCTs) investigating pharmacological treatments of CIN and FD in children (4-18 years). Cochrane risk of bias tool was used to assess methodological quality of the included articles. Expert commentary: Three RCTs (256 children with FD, 2-16 years) were included. No studies were found for CIN. All studies showed considerable risk of bias, therefore results should be interpreted with caution. Compared with baseline, successful relief of dyspeptic symptoms was found for omeprazole (53.8%), famotidine (44.4%), ranitidine (43.2%) and cimetidine (21.6%) (p = 0.024). Compared with placebo, famotidine showed benefit in global symptom improvement (OR 11.0; 95% CI 1.6-75.5; p = 0.02). Compared with baseline, mosapride versus pantoprazole reduced global symptoms (p = 0.011; p = 0.009). One study reported no occurrence of adverse events. This systematic review found no evidence to support the use of pharmacological drugs to treat CIN or FD in children. More high-quality clinical trials are needed.

ABBREVIATIONS

AP-FGID: Abdominal Pain Related Functional Gastrointestinal Disorders; BART: Biofeedback-Assisted Relaxation Training; CIN: Chronic Idiopathic Nausea; COS: Core Outcomes Sets; EPS: Epigastric Pain Syndrome; ESPGHAN: European Society for Pediatric Gastroenterology Hepatology and Nutrition; FAP: Functional Abdominal Pain; FD: Functional Dyspepsia; GERD: Gastroesophageal Reflux Disease; GES: Gastric Electrical Stimulation; H2RAs: H2 Receptor Antagonists; IBS: irritable bowel syndrome; NASPGHAN: North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition; PDS: Postprandial Distress Syndrome; PPIs: Proton Pump Inhibitor; PROMs: Patient Reported Outcome Measures; RCTs: Randomized Controlled Trials; SSRIs: selective serotonin reuptake inhibitors; TCAs: tricyclic antidepressants.

Proton pump inhibitors: Review of reported risks and controversies

Proton pump inhibitors (PPIs) are among the most prescribed classes of drugs in this day and age. These may be beneficial to treat many gastrointestinal conditions, such as gastroesophageal reflux or Barrett's esophagus as well as laryngopharyngeal reflux. However, many reports have emerged in the literature exposing the potential association of PPIs with various risks and complications such as bone fracture, infection, myocardial infarction, renal disease, and dementia. This review highlights many of these potential adverse side effects by exploring relevant publications and addressing the controversies associated with those findings. The diligent otolaryngologist should be aware of the current state of the literature and the risks associated with prescribing PPIs to insure proper counseling of their patients.

Level of Evidence

5

Proton pump inhibitors: use and misuse in the clinical setting

INTRODUCTION

The introduction of proton pump inhibitors (PPIs) into clinical practice has greatly improved our therapeutic approach to acid-related diseases for their efficacy and safety. Areas Covered: The following evidence-based indications for PPI use are acknowledged by many scientific societies: treatment of the various forms and complications of gastroesophageal reflux disease, eradication of H. pylori infection in combination with two or more antibiotics, short- and long-term therapy of H. pylori-negative peptic ulcers, healing, and prevention of NSAID/COXIB-associated gastric ulcers, co-therapy with endoscopic procedures to control upper digestive bleeding and medical treatment of Zollinger Ellison syndrome. Expert Commentary: Despite the above well-defined indications, however, the use of PPIs continues to grow every year in both western and eastern countries and the endless expansion of the PPI market has created important problems for many regulatory authorities for two relevant features: the progressive increase of the costs of therapy and the greater potential harms for the patients. The major reasons for the misuse of PPIs are the prevention of gastro-duodenal ulcers in patients without risk factors and the stress ulcer prophylaxis in non-intensive care units, steroid therapy alone, anti-platelet or anti-coagulant treatment in patients without risk of gastric injury and the overtreatment of functional dyspepsia.

Drug-induced lupus erythematosus: an update on drugs and mechanisms

PURPOSE OF REVIEW

Rapid introduction of newly developed drugs in the absence of clear understanding of the pathophysiologic mechanisms behind drug-induced lupus erythematosus (DILE) can sometimes make DILE difficult to recognize in clinical practice. The purpose of this review is to summarize drugs most recently reported to be involved in DILE and discuss the current landscape of diverse mechanisms involved.

RECENT FINDINGS

A large number of proton pump inhibitor (PPI)-induced subacute cutaneous lupus erythematosus cases have been reported, suggesting a shift over time in the spectrum of drugs implicated in DILE. Twenty-two articles comprising 29 DILE case reports published within the last 2 years are summarized in this review, including 12 (41.4%) systemic DILE. Antitumor necrosis factor (anti-TNF) drugs were the most frequently (41.7%) reported to introduce systemic DILE in these cases. Chemotherapeutic drugs were the most common drug class (54.5%) involved in subacute cutaneous lupus erythematosus, with an observed higher incidence in female patients. Enhanced neutrophil extracellular trap (NET) formation induced by procainamide and hydralazine could be a new mechanism contributing to the pathogenesis of DILE.

SUMMARY

The list of drugs implicated in triggering DILE is expanding as new drugs with novel mechanisms of action are being developed. It is important to recognize culprit drugs that may induce lupus erythematosus, as discontinuation usually results in improvement of drug-induced manifestations. Characterizing the mechanisms involved might help better understand the cause of idiopathic autoimmunity.

Association between Proton Pump Inhibitor Use and CNS Infection Risk: A Retrospective Cohort Study

This study investigated the incidence of central nervous system (CNS) infection following the use of proton pump inhibitors (PPIs). A retrospective cohort study was conducted in Taiwan by using data from the National Health Insurance Research Database. We identified and enrolled 16,241 patients with CNS infection who used PPIs (PPI users). The patients were individually propensity score matched (1:1) according to age, sex, hypertension, hyperlipidemia, Charlson comorbidity index (CCI), H2 blocker, non-steroidal anti-inflammatory drugs (NSAIDs), corticosteroid, and immunosuppressant use with 16,241 controls (PPI nonusers). A Cox proportional hazards model was used to estimate adjusted hazard ratio (aHR) for CNS infection in the PPI users and nonusers. After adjustment for other confounding factors, the incidence of CNS infection in the PPI users was 2.23-fold higher than that in the PPI nonusers (95% CI = 1.27⁻3.94). In addition, the PPI users exhibited a higher risk of CNS infection than the nonusers in the hypertension and CCI = 1 groups (aHR = 3.80, 95% CI = 1.40⁻10.32; aHR = 2.47, 95% CI = 1.07⁻5.70 in the PPI users and nonusers, respectively). In conclusions, according to these results, we concluded that the incidence of CNS infection was higher in the PPI users than in the nonusers.

Use of proton pump inhibitors and risk of ischemic events in the general population

BACKGROUND AND AIMS

A potential increased risk of cardiovascular events has been suggested for proton pump inhibitors (PPIs), the most commonly prescribed drugs for the management of upper gastrointestinal disorders. We aimed to estimate the risk of hospitalization for cardio/cerebrovascular (CV) events in a cohort of incident PPI users.

METHODS

A nested case-control study was carried out using regional healthcare utilization databases. For each case (hospitalization for non-haemorrhagic CV event), up-to-five controls randomly selected from the cohort were matched by gender, age at cohort entry, and index date. Exposure was estimated as recency of therapy (current, recent and past users) and number of days covered. Adjusted conditional logistic regression was used to estimate the association between exposure and outcome.

RESULTS

Among new PPI users, we identified 17,832 cases and 89,160 controls (males 64.9%; mean age 58.9 years). Cases showed a significantly higher prevalence of use of drugs for diabetes, hypertension and hypercholesterolemia than controls. Risk of CV events was significantly higher for current (OR 1.61; 95%CI 1.55-1.68) and recent users (OR 1.15; 95%CI 1.06-1.26) compared to past users. Analogous results were found stratifying for cardiovascular (OR_current 1.71; 95%CI 1.63-1.81) and cerebrovascular events (OR_current 1.43; 95%CI 1.34-1.54). The increased risk was confirmed in subgroups by antithrombotic, statin use, or exposure duration. The same analysis for H2-antagonists use showed no significant results.

CONCLUSIONS

In primary care setting, PPI use was independently associated with increased risk of first-time cardiovascular event, consistent with the evidence that PPIs adversely impact vascular function, underlying the need to promote appropriate prescribing of these drugs.

Synthesis and drug efficacy validations of racemic-substituted benzimidazoles as antiulcer/antigastric secretion agents

Aim: Due to their effective binding affinity to receptors which are responsible for various diseases, benzimidazoles are often bioactive. Present study intended and carried out to synthesis, characterize and develop benzimidazole-based antiulcer drugs. Materials & methods: Established 8a–l were evaluated for gastric antisecretory/antiulcer properties using freshly prepared H+-K+-ATPase from goat fundus mucosa. Molecular docking was carried out to unveil best binding affinities with H+-K+-ATPase (protein data bank ID: 2XZB). Results: The obtained least inhibitory constant of 8a–l (18–92 nM) was comparable to the in vitro H+-K+-ATPase inhibition (IC50: 24–122 nM). Furthermore, the lethal effect of 8a–l to colon cancerous cells and nonharm effect to the normal cells was recognized through cytotoxicity studies. Conclusion: After all in silico, in vitro experimental and structure–activity relationship predictions, the antiulcer druggability potential of 8a–l was recognized. A future drug development study for the most potent compounds among 8a–l is strongly indorsed.

Comparison of Oral versus Intravenous Proton Pump Inhibitors in Preventing Re-bleeding from Peptic Ulcer after Successful Endoscopic Therapy

BACKGROUND

Proton pump inhibitors (PPIs) are now widely prescribed for the management of patients with acute upper gastrointestinal bleeding; although its optimal dose and route of administration has remained a controversial issue. The aim of this study was to assess the clinical effectiveness of high dose oral versus intravenous (IV) PPI after successful endoscopic therapy in patients with bleeding peptic ulcer disease.

METHODS

178 patients with active upper gastrointestinal bleeding due to a peptic ulcer with stigmata of high risk for re-bleeding entered the study. After successful endoscopic hemostasis, they were randomized to receive either high dose oral pantoprazole (80 mg stat and 80 mg twice daily for 3 days) or high dose intravenous pantoprazole (80 mg IV infusion within 30 minutes and 8 mg per hour for 3 days). After the 3rd day, the patients in both groups received oral pantoprazole 40 mg twice daily for one month. The end points were comparing the rate of re-bleeding or mortality, and the need for blood transfusion or surgery during the first month between the two groups.

RESULTS

There were not significant statistical differences between the two groups in the volume of blood transfusion, mean duration of hospital stay, need to surgery, or mortality rates. However, the rates of re-bleeding were 2.3% (2:88) in the IV group and 3.3% (3:90) in the oral group (p = 0.6).

CONCLUSION

According to our findings, it seems that high dose oral PPI can be a good alternative to high dose IV PPI in patients with bleeding peptic ulcer who are at high risk of re-bleeding. Due to the lower cost and the availability of oral PPIs, their use can be economically much more affordable.

Enantioselective Separation over a Chiral Biphenol-Based Metal-Organic Framework

A chiral porous 3D metal-organic framework (MOF) is constructed from an enantiopure carboxylate ligand of 1,1'-biphenol, which can be utilized as adsorbent for the separation of aromatic alcohols and sulfoxides with enantioselectivity of up to 99.4%. Single-crystal X-ray diffraction analysis reveals the binding sites and host-guest interactions clearly, providing microscopic insight into the origin of the enantiosorption in the framework.

Safety, tolerability, pharmacodynamics and pharmacokinetics of DWP14012, a novel potassium-competitive acid blocker, in healthy male subjects

BACKGROUND

A novel potassium-competitive acid blocker, DWP14012, is in clinical development as a potential alternative to proton pump inhibitors for the treatment of acid-related diseases.

AIMS

To evaluate the safety, tolerability, pharmacodynamics and pharmacokinetics of DWP14012 in humans.

METHODS

A randomised, double-blind, double-dummy, placebo- and active-controlled, single- and multiple-ascending dose (SAD and MAD, respectively) study was conducted in healthy male subjects without Helicobacter pylori infection. Subjects randomly received a single oral dose of 10-320 mg DWP14012, esomeprazole (active comparator) or placebo in the SAD study (n = 72) and once daily doses of 20-160 mg DWP14012, esomeprazole or placebo for 7 days in the MAD study (n = 48; 8:2:2). Tolerability was evaluated using a microRNA-122 assay. Pharmacodynamics were evaluated through 24-hour gastric pH monitoring, and pharmacokinetics were evaluated plasma and urine DWP14012 concentrations.

RESULTS

DWP14012 was generally well tolerated. The liver toxicity of DWP14012 was not higher than that of placebo after multiple oral administrations. DWP14012 showed rapid and sustained suppression of gastric acid secretion for 24 hours after dosing. Clear dose-response and exposure-response relationships were observed. Plasma concentrations of DWP14012 increased in a dose-proportional manner in the MAD study, whereas in the SAD study, DWP14012 did not significantly accumulate in the plasma.

CONCLUSIONS

DWP14012 was well tolerated, and showed a rapid and long-lasting gastric acid suppression effect in healthy subjects. These results justify further investigation of DWP14012 in patients with acid-related disorders.

Safe use of proton pump inhibitors in patients with cirrhosis

Aims

Proton pump inhibitors (PPIs) belong to the most frequently used drugs, also in patients with cirrhosis. PPIs are extensively metabolized by the liver, but practice guidance on prescribing in cirrhosis is lacking. We aim to develop practical guidance on the safe use of PPIs in patients with cirrhosis.

Methods

A systematic literature search identified studies on the safety (i.e. adverse events) and pharmacokinetics of PPIs in cirrhotic patients. This evidence and data from the product information was reviewed by an expert panel who classified drugs as safe; no additional risks known; additional risks known; unsafe; or unknown. Guidance was aimed at the oral use of PPIs and categorized by the severity of cirrhosis, using the Child–Turcotte–Pugh (CTP) classification.

Results

A total of 69 studies were included. Esomeprazole, omeprazole and rabeprazole were classified as having ‘no additional risks known’. A reduction in maximum dose of omeprazole and rabeprazole is recommended for CTP A and B patients. For patients with CTP C cirrhosis, the only PPI advised is esomeprazole at a maximum dosage of 20 mg per day. Pantoprazole and lansoprazole were classified as unsafe because of 4‐ to 8‐fold increased exposure. The use of PPIs in cirrhotic patients has been associated with the development of infections and hepatic encephalopathy and should be carefully considered.

Conclusions

We suggest using esomeprazole, omeprazole or rabeprazole in patients with CTP A or B cirrhosis and only esomeprazole in patients with CTP C. Pharmacokinetic changes are also important to consider when prescribing PPIs to vulnerable, cirrhotic patients.

Managing Polypharmacy in the 15-Minute Office Visit

Polypharmacy is an underappreciated factor in undesirable patient outcomes. In older adults, polypharmacy is considered a syndrome of harm and presents a challenge to primary care providers. The United States has one of the highest medication use rates per capita in the world. With the aging population, and polypharmacy a significant part of the lives of older adults, management of polypharmacy poses both a growing challenge and an opportunity for all health care providers. This article provides an overview of skills to improve medication use management in older adults living with polypharmacy.

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.

Efficacy and Safety Profile of Z-215 (Azeloprazole Sodium), a Proton Pump Inhibitor, Compared with Rabeprazole Sodium in Patients with Reflux Esophagitis: A Phase II, Multicenter, Randomized, Double-Blind, Comparative Study

BACKGROUND

The metabolism of many proton pump inhibitors is influenced by CYP2C19 genotype, which is a limitation of their use.

OBJECTIVES

To determine the efficacy and safety profile of Z-215 (azeloprazole sodium) as initial treatment for reflux esophagitis (RE), dose response, and optimal dose compared with rabeprazole sodium (RPZ).

METHODS

We conducted an exploratory, multicenter, randomized, double-blind, parallel-group study in Japan. Patients with RE aged ≥20 years were enrolled and randomly assigned to receive 10, 20, or 40 mg Z-215 or 10 mg RPZ (1:1:1:1), and orally administered the respective drug for 8 weeks. The primary efficacy end point was the endoscopic healing rate after 8 weeks of treatment (at Week 8). We also assessed the effects of CYP2C19 genotype. Safety end points were the incidence of adverse events and adverse drug reactions.

RESULTS

Five hundred three patients received the study drugs (10 mg Z-215: 125 patients, 20 mg Z-215: 126 patients, 40 mg Z-215: 126 patients, and 10 mg RPZ: 126 patients). The endoscopic healing rate at Week 8 was above 95% in all groups (10 mg Z-215: 95.2%, 20 mg Z-215: 96.8%, 40 mg Z-215: 95.2%, and 10 mg RPZ: 96.8%). The endoscopic healing rate and serum gastrin levels of the Z-215 groups were not influenced by CYP2C19 genotype. In patients with Grade C/D, the endoscopic healing rate at Week 4 was slightly higher in the 40-mg Z-215 group compared with the other groups. Incidences of adverse events/adverse drug reactions did not markedly differ between the Z-215 and 10-mg RPZ groups.

CONCLUSIONS

Z-215 was as effective and well tolerated as 10 mg RPZ in the treatment of RE in this selected population. CYP2C19 genotype status may not influence the efficacy and safety of Z-215. There were no clear dose-response effects between Z-215 doses in the endoscopic healing of RE. These findings suggest that Z-215 may be 1 option for the initial treatment of RE. ClinicalTrials.gov identifier: NCT 02463643.

Efficacy of vonoprazan for 24-week maintenance therapy of patients with healed reflux esophagitis refractory to proton pump inhibitors

The aim of the present study was to evaluate the efficacy of a potassium-competitive acid blocker (P-CAB), vonoprazan, for the maintenance therapy of healed reflux esophagitis (RE). A total of 60 patients were enrolled in this open-label, single-center, prospective study. All patients were diagnosed with RE with a frequency scale for the symptoms of gastroesophageal reflux disease (FSSG) total score ≥8 following treatment with standard proton pump inhibitors (PPIs) for a minimum of 8 weeks. Standard PPI treatment was switched to vonoprazan 20 mg once daily for 4 weeks. A total of 52 patients, who had no endoscopic evidence of erosive esophagitis following vonoprazan treatment, received maintenance therapy with vonoprazan 10 mg once daily for 24 weeks. Symptoms were evaluated using the FSSG and Gastrointestinal Symptom Rating Scale (GSRS). Upper gastrointestinal endoscopies were performed following 24 weeks of maintenance therapy. The primary endpoint was to determine the proportion of patients who exhibited maintenance of healed RE refractory to PPIs following 24 weeks of maintenance therapy with vonoprazan 10 mg once daily. Secondary endpoints included evaluation of the proportion of patients with symptomatic non-relapse at 24 weeks. Maintenance therapy with vonoprazan 10 mg once daily prevented relapse of esophageal mucosal breaks in 37/43 (86.0%) patients at 24 weeks. However, the number of patients with symptomatic relapse was 1 (1.9%) and 4 (7.7%) at 4 and 8 weeks, respectively. A total of 4 patients were withdrawn due to loss to follow-up. At the end of the 24-week maintenance period, the symptomatic non-relapse rate for acid reflux-associated and dysmotility symptom FSSG scores were 86.5 and 80.8%, respectively. Furthermore, the symptomatic non-relapse rate for reflux, abdominal pain, indigestion, diarrhea, and constipation GSRS scores at 24 weeks were 86.5, 80.8, 75.0, 71.2 and 76.9%, respectively. No serious adverse events were reported during the study. The mean gastrin level was 1,059 pg/ml. In conclusion, the results of the present study indicate that vonoprazan 10 mg once daily is effective for 24-week maintenance therapy of healed RE refractory to PPIs.

Stereoselective Inhibition of Renal Basolateral Human Organic Anion Transporter 3 by Lansoprazole Enantiomers

Lansoprazole, a proton pump inhibitor, potently inhibits human organic anion transporter, hOAT3 (SLC22A8). Lansoprazole has an asymmetric atom in its structure and is clinically administered as a racemic mixture of (R)-and (S)-enantiomers. However, little is known about the stereoselective inhibitory potencies of lansoprazole against hOAT3 and its homolog, hOAT1. In the present study, the stereoselective inhibitory effect of lansoprazole was evaluated using hOAT1-and hOAT3-expressing cultured cells. hOAT1 and hOAT3 transported [14C]p-aminohippurate and [3H]estrone-3-sulfate (ES) with Michaelis-Menten constants of 29.8 ± 4.0 and 30.1 ± 9.0 µmol/L respectively. Lansoprazole enantiomers inhibited hOAT1- and hOAT3-mediated transport of each substrate in a concentration-dependent manner. The IC50 value of (S)-lansoprazole against hOAT3-mediated transport of [3H]ES (0.61 ± 0.08 µmol/L) was significantly lower than that of (R)-lansoprazole (1.75 ± 0.31 µmol/L). In contrast, stereoselectivity was not demonstrated for the inhibition of hOAT1. Furthermore, (S)-lansoprazole inhibited hOAT3-mediated transport of pemetrexed and methotrexate (hOAT3 substrates) more strongly than the corresponding (R)-lansoprazole. This study is the first to demonstrate that the stereoselective inhibitory potency of (S)-lansoprazole against hOAT3 is greater than that of (R)-lansoprazole. The present findings provide novel information about the drug interactions associated with lansoprazole.