Physical and chemical stability of esomeprazole sodium solutions

Separation and identification of degradation impurities of esomeprazole sodium

Drug impurities are important factors that affect drug safety and efficacy. The aim of this study is to separate and confirm the structure of two degradation impurities of esomeprazole sodium, designated X and Y. The impurities X and Y were successfully isolated using preparative HPLC by developing separation methods with the help of ACD/Labs AutoChrom software. There was a steady increase in X and Y impurities in forced esomeprazole sodium degradation. Impurity X was confirmed as 6-methoxy-1h-benzo[d]imidazole-2-yl-4-amino-3,5-dimethylpyridinecarboxylate and impurity Y as 6-methoxy-1h-benzo[d]imidazole-2-yl-4-hydroxy-3,5-dimethylpyridinecarboxylate using nuclear magnetic resonance spectrometry, infrared spectroscopy, and high-resolution mass spectrometry. These findings provide a comprehensive understanding of the impurity profile of esomeprazole sodium because these impurities are reported for the first time. Based on our results, active pharmaceutical ingredient manufacturers can further control process parameters to reduce impurity generation, and drug production manufacturers can optimize the packaging and storage conditions of esomeprazole sodium.

Administering esomeprazole subcutaneously via a syringe driver in the palliative demographic: A case series

WHAT IS KNOWN AND OBJECTIVE

Proton pump inhibitors are potent suppressors of gastric acid secretion, and are commonly prescribed in palliative medicine. Despite multiple relevant indications in patients at the end-of-life, their use is often precluded as oral and intravenous administration is frequently inappropriate or not possible. Limited anecdotal evidence suggests proton pump inhibitors may be administered subcutaneously. Our objective was to investigate the tolerability and effectiveness of the administration of esomeprazole as a continuous subcutaneous infusion over 24 h via a syringe driver.

METHODS

Case series (n = 7) design assessing sequential patients admitted to a specialist inpatient centre for palliative care, who required parenteral proton pump inhibitor therapy.

RESULTS AND DISCUSSION

Four patients reported complete resolution of dyspeptic and reflux symptoms post commencement of esomeprazole. Two patients developed upper gastrointestinal bleeding, which via observation of vomitus and stools, resolved with the initiation of esomeprazole. A single patient, deemed high risk of gastrointestinal bleeding, was commenced on esomeprazole and no bleeding events occurred.

WHAT IS NEW AND CONCLUSION

Esomeprazole when administered via a syringe driver over 24 h appears well tolerated and effective for the symptomatic management of dyspepsia and treatment of gastrointestinal bleeding. Overall, this series adds to the limited evidence base for using subcutaneous proton pump inhibitors in the palliative demographic.

Compatibility of proton pump inhibitors in a preservative-free suspending vehicle

Objectives

To evaluate the microbiological and physicochemical compatibility of commonly used proton pump inhibitors (PPIs) esomeprazole, lansoprazole, omeprazole and pantoprazole compounded at a single concentration using SyrSpend SF Alka and stored at refrigerated temperatures (omeprazole was also stored at room temperature because it has the most widespread use).

Methods

Compatibility was assessed by measuring the per cent recovery at varying time points throughout a 90-day period. Quantification of the APIs was performed by a validated high performance liquid chromatography (HPLC-UV) method. This same assay was also used to determine the dosage content uniformity of the suspensions. Microbiological stability ('test in use') was assessed during 60 days and total aerobic microbial count (TAMC), total combined yeasts and moulds count (TYMC), detection of Escherichia coli and pH determination were performed. Antimicrobial effectiveness testing was determined following European Pharmacopoeia guidelines.

Results

Beyond-use dates of maximum 60 days for omeprazole (5 mg/mL), pantoprazole (3 mg/mL) and esomeprazole (3 mg/mL) were established. All suspensions that met the physicochemical criteria for stability also met the content uniformity criteria. The suspensions showed no antimicrobial efficiency against bacteria, yeasts and moulds as SyrSpend SF Alka is an unpreserved vehicle, but the 'test in use' showed that the suspensions can remain microbiologically stable for up to 60 days.

Conclusions

SyrSpend SF Alka can be used to compound palatable (taste-masking properties) preservative-free oral suspensions with almost all commonly used PPIs.