Failure of proton pump inhibitors to treat GERD in neonates and infants: a question of drug, diagnosis, or design. Clin Pharmacol Ther. 2012;92:388-392. [PMID: 22805424 DOI: 10.1038/clpt.2012.86]

Appropriateness of proton pump inhibitors use in noncritically ill hospitalized children in a tertiary hospital in Saudi Arabia

Background

Studies assessing the appropriate use of proton pump inhibitors (PPIs) for hospitalized noncritically ill pediatric patients are lacking. Therefore, this study aimed to assess the suitability of PPI prescriptions in noncritically ill pediatric patients.

Methods

This cross sectional retrospective study was conducted at a maternity hospital in Qassim, Saudi Arabia from November 2020 to January 2021. All noncritically ill hospitalized children aged 14 years and below who received PPIs were included. The endpoints included the number and percentage of patients who appropriately received PPIs in general and in each age category. The collected data were analyzed using Microsoft Excel (version 2208, Microsoft Corp., Redmond, WA, USA).

Results

In total, 332 medical records were screened, of which 246 were included. Of all patients, 49.2% were children and 50.8% were infants, with the average age at admission being 5.39 ± 5.4 years years. More than half of the patients were female, and the average weight of patients was 19.8 kg. Omeprazole was appropriately used in 95 (38.5%) patients. Based on age groups, omeprazole was appropriately used in 66.3% of children and 38.4% of infants.

Conclusion

The use of omeprazole in noncritically ill pediatrics was only deemed appropriate in 38.6% of the study population. This result indicates that this medication was overused in the institution. Additional research is required to confirm this on a nationwide scale.

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.

Toxicity of long-term use of proton pump inhibitors in children

Proton pump inhibitor (PPI) use is becoming increasingly common. Although the toxicity profiles of PPIs are not well understood particularly in children, PPIs have been associated with increased risks of gastrointestinal and respiratory tract infection, vitamin B₁₂ deficiency, hypomagnesaemia, bone fractures, and rebound hyperacidity after discontinuation. Prescribers should take into account that PPI uses pose toxicity risks, which remain to be fully characterised in infants and children.

Dose-Finding Study of Omeprazole on Gastric pH in Neonates with Gastro-Esophageal Acid Reflux Using a Bayesian Sequential Approach

Objective

Proton pump inhibitors are frequently administered on clinical symptoms in neonates but benefit remains controversial. Clinical trials validating omeprazole dosage in neonates are limited. The objective of this trial was to determine the minimum effective dose (MED) of omeprazole to treat pathological acid reflux in neonates using reflux index as surrogate marker.

Design

Double blind dose-finding trial with continual reassessment method of individual dose administration using a Bayesian approach, aiming to select drug dose as close as possible to the predefined target level of efficacy (with a credibility interval of 95%).

Setting

Neonatal Intensive Care unit of the Robert Debré University Hospital in Paris, France.

Patients

Neonates with a postmenstrual age ≥ 35 weeks and a pathologic 24-hour intra-esophageal pH monitoring defined by a reflux index ≥ 5% over 24 hours were considered for participation. Recruitment was stratified to 3 groups according to gestational age at birth.

Intervention

Five preselected doses of oral omeprazole from 1 to 3 mg/kg/day.

Main outcome measures

Primary outcome, measured at 35 weeks postmenstrual age or more, was a reflux index <5% during the 24-h pH monitoring registered 72±24 hours after omeprazole initiation.

Results

Fifty-four neonates with a reflux index ranging from 5.06 to 27.7% were included. Median age was 37.5 days and median postmenstrual age was 36 weeks. In neonates born at less than 32 weeks of GA (n = 30), the MED was 2.5mg/kg/day with an estimated mean posterior probability of success of 97.7% (95% credibility interval: 90.3–99.7%). The MED was 1mg/kg/day for neonates born at more than 32 GA (n = 24).

Conclusions

Omeprazole is extensively prescribed on clinical symptoms but efficacy is not demonstrated while safety concerns do exist. When treatment is required, the daily dose needs to be validated in preterm and term neonates. Optimal doses of omeprazole to increase gastric pH and decrease reflux index below 5% over 24 hours, determined using an adaptive Bayesian design differ among neonates. Both gestational and postnatal ages account for these differences but their differential impact on omeprazole doses remains to be determined.

Widespread use of gastric acid inhibitors in infants: Are they needed? Are they safe?

Gastroesophageal reflux is a common phenomenon in infants, but the differentiation between gastroesophageal reflux and gastroesophageal reflux disease can be difficult. Symptoms are non-specific and there is increasing evidence that the majority of symptoms may not be acid-related. Despite this, gastric acid inhibitors such as proton pump inhibitors are widely and increasingly used, often without objective evidence or investigations to guide treatment. Several studies have shown that these medications are ineffective at treating symptoms associated with reflux in the absence of endoscopically proven oesophagitis. With a lack of evidence for efficacy, attention is now being turned to the potential risks of gastric acid suppression. Previously assumed safety of these medications is being challenged with evidence of potential side effects including GI and respiratory infections, bacterial overgrowth, adverse bone health, food allergy and drug interactions.

A Survey of Neonatal Pharmacokinetic and Pharmacodynamic Studies in Pediatric Drug Development

Conducting clinical trials in neonates is challenging, and knowledge gaps in neonatal clinical pharmacology exist. We surveyed the US Food and Drug Administration databases and identified 43 drugs studied in neonates or referring to neonates between 1998 and 2014. Twenty drugs were approved in neonates. For 10 drugs, approval was based on efficacy data in neonates, supplemented by pharmacokinetic data for four drugs. Approval for neonates was based on full extrapolation from older patients for six drugs, and partial extrapolation was the basis of approval for four drugs. Dosing recommendations differed from older patients for most drugs, and used body-size based adjustment in neonates. Trial failures were associated with various factors including inappropriate dose selection. Successful drug development in neonates could be facilitated by an improved understanding of the natural history and pathophysiology of neonatal diseases and identification and validation of clinically relevant biomarkers.

Pantoprazole decreases gastroesophageal muscle tone in newborn rats via rho-kinase inhibition

Proton pump inhibitors reduce gastric acid secretion and are commonly utilized in the management of gastroesophageal reflux disease across all ages. Yet a decrease in lower esophageal sphincter tone has been reported in vitro in rats through an unknown mechanism; however, their effect on the gastroesophageal muscle tone early in life was never studied. Hypothesizing that proton pump inhibitors also reduce gastroesophageal muscle contraction in newborn and juvenile rats, we evaluated the in vitro effect of pantoprazole on gastric and lower esophageal sphincter muscle tissue. Electrical field stimulation and carbachol-induced force were significantly (P < 0.01) reduced in the presence of pantoprazole, whereas the drug had no effect on the neuromuscular-dependent relaxation. When administered in vivo, pantoprazole (9 mg/kg) significantly (P < 0.01) reduced gastric emptying time at both ages. To ascertain the signal transduction pathway responsible for the reduction in muscle contraction, we evaluated the tissue ROCK-2 and CPI-17 activity. Pantoprazole reduced myosin light chain phosphatase MYPT-1, but not CPI-17 phosphorylation of gastric and lower esophageal sphincter tissue, strongly suggesting that it is a ROCK-2 inhibitor. To the extent that these findings can be extrapolated to human neonates, the use of pantoprazole may impair gastric and lower sphincter muscle tone and thus paradoxically exacerbate esophageal reflux. Further studies addressing the effect of proton pump inhibitors on gastroesophageal muscle contraction are warranted to justify its therapeutic use in gastroesophageal reflux disease.

Off-label use of medicine in pediatrics: focus on gastrointestinal diseases

PURPOSE OF REVIEW

To provide current information on off-label medication use in pediatric gastroenterology, including a discussion on US legislative efforts to address the issue.

RECENT FINDINGS

Medications used to treat pediatric gastrointestinal illnesses are frequently prescribed off-label. Acid suppressors, antiemetics, laxatives, and antitumor necrosis factor therapies are types of medications frequently used off-label in the pediatric gastroenterology arena. Pediatric studies conducted under US Federal laws are generating much-needed data on the safety and effectiveness of medications used to treat pediatric patients. Moreover, a new US law, the Food and Drug Administration Safety and Innovation Act, may further the development of pediatric medications in part by requiring pediatric-specific study plans earlier in the overall drug development process. As of today, there still are gaps in our knowledge about these medications, including for the treatment of pediatric gastroenterology diseases.

SUMMARY

Medications are widely used off-label in pediatrics, including medications intended to treat gastrointestinal diseases, such as antitumor necrosis factor and laxatives. Although legislation is helping to generate and make available important information about pediatric medications, most still do not contain pediatric data. Therefore, providers need to understand the potential risks and benefits of prescribing off-label products to pediatric patients.

Synthesis and <i>In Vitro</i> Anti-Ulcer Effect of Triazolo-Methyl Tetrahydrobenzofuran Oxime Ether Derivatives

The triazolo-methyl tetrahydrobenzofuran oxime ether isomers were prepared through Cu (II)-catalyzed Huisgen 1,3-dipolar cycloaddition reaction in a high-yielding three-step reaction sequence under mild conditions. All of the intermediates and target compounds were characterized by NMR, IR, ESI-MS and elemental analysis. The in vitro anti-ulcer activity evaluation indicated the (Z)-oxime isomer of triazolo-methyl tetrahydrobenzofuran oxime ether exhibited most potent H+/K+-ATPase inhibitory effect with the IC50˰̵̱̼͆ͅ˰̶̿˰̅˾́̅˰μ̝˾ These compounds could be potentially used as anti-ulcer agents for the treatment of acid related diseases.