Genotype tailored treatment of mild symptomatic acid reflux in children with uncontrolled asthma (GenARA): Rationale and methods

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.

Pharmacogenetic Aspects of Drug Metabolizing Enzymes and Transporters in Pediatric Medicine: Study Progress, Clinical Practice and Future Perspectives

As the activity of certain drug metabolizing enzymes or transporter proteins can vary with age, the effect of ontogenetic and genetic variation on the activity of these enzymes is critical for the accurate prediction of treatment outcomes and toxicity in children. This makes pharmacogenetic research in pediatrics particularly important and urgently needed, but also challenging. This review summarizes pharmacogenetic studies on the effects of genetic polymorphisms on pharmacokinetic parameters and clinical outcomes in pediatric populations for certain drugs, which are commonly prescribed by clinicians across multiple therapeutic areas in a general hospital, organized from those with the most to the least pediatric evidence among each drug category. We also further discuss the research status of the gene-guided dosing regimens and clinical implementation of pediatric pharmacogenetics. More and more drug-gene interactions are demonstrated to have clinical validity for children, and pharmacogenomics in pediatrics have shown evidence-based benefits to enhance the efficacy and precision of existing drug dosing regimens in several therapeutic areas. However, the most important limitation to the implementation is the lack of high-quality, rigorous pediatric prospective clinical studies, so adequately powered interventional clinical trials that support incorporation of pharmacogenetics into the care of children are still needed.

Randomised trials of proton pump inhibitors for gastro-oesophageal reflux disease in patients with asthma: an updated systematic review and meta-analysis

OBJECTIVE

Asthma often coexists with gastro-oesophageal reflux disease (GERD). The effect of proton pump inhibitors (PPIs) treatment on asthma concomitant with GERD was inconsistent. This study aimed to assess whether PPIs treatment improved morning peak expiratory flow (mPEF) in asthma patients with GERD.

DATA SOURCES

PubMed, MEDLINE, EMBASE, Web of Science, Cochrane Library and ClinicalTrials.gov; hand searching for reference lists; contacted with authors if necessary.

STUDY SELECTION

All eligible trials were randomised clinical trials comparing PPIs with placebo in asthma patients accompanying with GERD.

RESULTS

Fourteen randomised clinical trials (2182 participants) were included. Overall, PPIs versus placebo did not affect mPEF in patients with asthma having GERD (weighted mean difference 8.68 L/min, 95% CI -2.02 to 19.37, p=0.11). Trial sequential analysis (TSA) further confirmed this finding (TSA adjusted 95% CI -1.03 to 22.25). Subgroups analyses based on the percentage of patients with symptomatic GERD≥95%, treatment duration >12 weeks also found no statistically significant benefit on mPEF. Similarly, analyses of secondary outcomes (evening PEF, forced expiratory volume in 1 s, asthma symptoms score, asthma quality of life score and episodes of asthma exacerbation) did not show significant difference between PPIs and placebo.

CONCLUSION

In this meta-analysis, PPIs therapy did not show a statistically significant improvement on mPEF in asthma patients having GERD, neither in subgroup with symptomatic GERD nor in subgroup with treatment duration >12 weeks. This analysis does not support a recommendation for PPIs therapy as empirical treatment in asthma patients with GERD.

PROSPERO REGISTRATION NUMBER

CRD42020177330.

[Treatment of GERD in asthma]

Gastro-oesophageal reflux disease (GORD) is one of the most frequent conditions associated with asthma. GORD has an impact on asthma control and quality of life of asthmatic patients. Its treatment relies on lifestyle modifications, anti-acidic treatment with proton pump inhibitors (PPI) and/or surgical management by fundoplication in some situations. The impact of lifestyle modifications has not been analysed on asthma outcomes alone. Several randomised controlled trials assessed the efficacy of PPI on asthma control, peak expiratory flow and/or quality of life. The impact of fundoplication in asthma has mainly been analysed in retrospective or prospective observational studies. This review highlights the limited impact of GORD treatment on asthma control. Current guidelines are to restrict GORD treatment in asthma to asthmatic patients with actual symptomatic GORD. Given the lack of controlled studies, the place of surgical management of GORD in asthma is currently not defined.

Current therapies for gastro-oesophageal reflux in the setting of chronic lung disease: state of the art review

The inter-relationship between chronic respiratory disease and reflux disease in the airway reflux paradigm is extremely complex and remains poorly characterised. Reflux disease is reported to cause or contribute to the severity of a number of respiratory tract diseases including laryngeal disorders, sinusitis, chronic cough, asthma, COPD, idiopathic pulmonary fibrosis, cystic fibrosis, bronchiectasis and bronchiolitis obliterans post lung transplant. It is now appreciated that reflux disease is not simply caused by liquid acid reflux but rather by a variety of chemical refluxates originating from the stomach and duodenum due to a number of different mechanisms. Reflux disease can be challenging to diagnose, particularly proving its role in the causation of direct respiratory epithelial damage. Significant advances in oesophageal assessment and gastric biomarkers have emerged in recent years as our understanding increases. There are a number of treatments available for reflux disease, both medical and surgical, but there is a paucity of large randomised trials to evaluate their efficacy in the setting of chronic respiratory disease. Everyday clinical practice, however, informs us that treatment failure in reflux disease is common. This clinical review summarises associations between reflux disease in the setting of chronic respiratory diseases and examines available evidence regarding potential therapeutic strategies.

Gastro-oesophageal reflux disease is prevalent among patients with chronic respiratory disease. A number of medical and surgical treatment options are available for GORD. This review examines available evidence in the setting of chronic lung disease.https://bit.ly/34TcMJS

Clinical Pharmacogenetics Implementation Consortium (CPIC) Guideline for CYP2C19 and Proton Pump Inhibitor Dosing

Proton pump inhibitors (PPIs) are widely used for acid suppression in the treatment and prevention of many conditions, including gastroesophageal reflux disease, gastric and duodenal ulcers, erosive esophagitis, Helicobacter pylori infection, and pathological hypersecretory conditions. Most PPIs are metabolized primarily by cytochrome P450 2C19 (CYP2C19) into inactive metabolites, and CYP2C19 genotype has been linked to PPI exposure, efficacy, and adverse effects. We summarize the evidence from the literature and provide therapeutic recommendations for PPI prescribing based on CYP2C19 genotype (updates at www.cpicpgx.org). The potential benefits of using CYP2C19 genotype data to guide PPI therapy include (i) identifying patients with genotypes predictive of lower plasma exposure and prescribing them a higher dose that will increase the likelihood of efficacy, and (ii) identifying patients on chronic therapy with genotypes predictive of higher plasma exposure and prescribing them a decreased dose to minimize the risk of toxicity that is associated with long-term PPI use, particularly at higher plasma concentrations.

DIAGNOSTIC VALUE OF MORPHOLOGICAL CHANGES IN GASTROESOPHAGEAL REFLUX DISEASE IN BIOPSY MATERIAL OF THE DISTAL ESOPHAGUS IN ADOLESCENTS SICKLY WITH ACUTE RESPIRATORY DISEASES

The article dedicated to the problem of the diagnostic value of morphological changes in gastroesophageal reflux disease in the biopsy of the distal esophagus in pubertal children of childbearing age. Aim of the research is to investigate the diagnostic value of morphological changes in gastroesophageal reflux disease in esophageal biopsy material in adolescents sickly with acute respiratory diseases. Methodology. The objective of the study was achieved through examination of 90 adolescents (10 to 16 years old, average age 13.1±3.54 years) kept under observation at the Children’s Clinical Hospital No. 9 of Kyiv and on the basis of the Department of Pediatrics No. 1 Center of Primary Health Care No. 4 of the Desnianskyi district of Kyiv. All adolescents belonged to the group of sickly with a number of respiratory diseases averaging 6-8 times a year, lasting from 8 to 18 days (on average 12.8±5.41 days). All children have undergone endoscopic examination of the esophagus, stomach and duodenum with the esophagus mucosa biopsy using the OLYMPUS GIF-P3 flexible fiberscope. Results. It was found that the least valuable diagnostic feature in the morphological examination of the mucous membrane of the distal esophagus in the pain-causing children with GERD was thickening of the epithelium with a sensitivity of 13,0 %, a specificity of 96.0 %, and total value of 65.0 %. It has been proved that hyperplasia of cells of the basal layer of the mucous membrane of the distal esophagus at the GERD in the infected children is 46.7 % (specificity – 93.3 %, the total value is 75.6 %). Increase in the number of papillae and their prolongation in 33.3 % cases (sensitivity – 33.3 %, specificity – 93.3 %, overall diagnostic value – 70.8 %). Conclusion. The peculiarity of the morphological manifestations of GERD in childbearing children is dystrophic changes in keratocytes in the superficial parts of the multilayer squamous epithelium, which are detected at 100.0 % of patients (specificity is 93.3 %, total value is 96.8 %), with parakeratosis centers at 13.3 % of cases. It has been shown that a frequent and diagnostically valuable indication is inflammatory infiltration of the esophageal mucosa, which are verified in all cases (100.0 %, with dilatation and hyperemia in 46.7 % of patients (specificity – 40.0 %, total value – 81.3 %).