High Dose Pantoprazole for Gastroesophageal Reflux Disease: Need, Evidence, Guidelines and Our Experience.

Gastroesophageal reflux disease (GERD) has a pooled prevalence of 15.2% in India with varying presentation in different subset of patients. The approach towards the management of GERD includes use of monotherapy or a combination of OTCs like antacids and/or prescription drugs like H2 receptor antagonists and proton pump inhibitors (PPI). Better efficacy and safety profile of PPIs have contributed to its wide spread use as compared with other drugs for the same indication. Among PPIs, most of the healthcare professionals prefer to prescribe pantoprazole in India. Standard dose of Pantoprazole (40 mg) is unable to meet the needs in case of extraesophageal symptoms, partial responders, patients with concomitant use of non-steroidal anti-inflammatory drugs (NSAIDs), or severe presentation in cases of overweight/obese patients. Multiple guidelines recommend doubling the dose of PPI in such cases. Twice daily dosing of PPI may reduce compliance. Thus, there is a need for a higher dose of Pantoprazole (80 mg) to be prescribed once daily in these cases so that improved compliance leads to better outcomes. The use of dual release Pantoprazole 80 mg may help to improve compliance and also enhance the time for which acid suppression takes place. In this review, we discuss the use of higher dose PPI based on scientific evidence and experience of clinicians for the same. How to cite this article: Upadhyay R, Soni NK, Kotamkar AA, et al. High Dose Pantoprazole for Gastroesophageal Reflux Disease: Need, Evidence, Guidelines and Our Experience. Euroasian J Hepato-Gastroenterol 2024;14(1):86-91.

A liquid chromatography-tandem mass spectrometry method for the determination of apixaban in human plasma and its application to pharmacokinetics studies in the Indian population.

Apixaban is a novel oral anticoagulant intended to treat and prevent blood clots and to prevent strokes in patients with nonvalvular atrial fibrillation. The development and validation of a fast, selective, accurate, and precise method using high-performance liquid chromatography tandem mass spectrometry is described for the estimation of apixaban in human plasma, with apixaban 13CD3 as an internal standard (IS). Using a reverse phase Gemini C18 column (50 mm × 4.6 mm, 3 µm) and a mixture of acetonitrile (2 mM) and ammonium formate buffer (50 : 50 v/v) as the mobile phase, chromatographic separation was achieved following extraction via a solid-phase extraction process. To track multiple reaction monitoring transitions set at 460/443 (m/z) and 464/447 (m/z) for apixaban and apixaban 13CD3, respectively, liquid chromatography coupled with triple quadrupole mass spectrometry was employed. A concentration linearity range between 1.01 and 280.00 ng mL-1 was validated with regression ≥0.99, and the method was successfully applied to apixaban pharmacokinetics analysis. At a flow rate of 1.0 mL min-1, the run time was around 1.8 min, which is short. With an extraction recovery of >73% for both apixaban and apixaban 13CD3, the method was sensitive, with a limit of quantitation of 1.01 ng mL-1. The inter-day/between-run precision ranged from 1.21% to 3.21%, while the accuracy ranged from 96.5% to 102%. For pharmacokinetics analysis, the validated method was applied. The percentage difference between findings from samples that were reanalyzed and samples that were initially analyzed was within ±20%. With high-quality assay specificity and accuracy in relation to apixaban analysis in human plasma under the experimental conditions used, the method provided is accurate.

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determination of free and total dabigatran in human plasma and its application to a pharmacokinetic study.

A high-performance liquid chromatography-tandem mass spectrometric method for the determination of free and total dabigatran in human plasma has been developed and validated using a stable labeled internal standard (IS) as dabigatran D4. The extraction of analyte and IS was accomplished by the solid-phase extraction technique. Chromatographic separations were achieved using Peerless basic C8 (150 × 4.6) mm, 5 µ column eluted at a flow rate of 1 mL/min with mobile phase Acetonitrile: 5 mM ammonium formate: Methanol and 0.2% formic acid (30:20:50, v/v/v). The run time of the method was about 2.5 min with elution times of dabigatran and dabigatran D4 at around 1.2 min. The multiple reaction monitoring transitions (Q1/Q3) were set at 472/289, 172 (m/z) for dabigatran, and 476/293 (m/z) for dabigatran D4. The calibration curves were linear (r2 ≥0.99) over the range of 1.04-406.49 ng/mL. The presented method was successfully employed in the analysis of pharmacokinetic studies with the added advantage of demonstrating the effect of co-administration of dabigatran with the proton pump inhibitor pantoprazole on bioavailability and pharmacokinetic characteristics. Re-analysis of incurred sample resulted in >98% compliance indicating good assay precision of target analytes.

Development of LC-MS/MS method for simultaneous determination of Canagliflozin and Metformin in human plasma and its pharmacokinetic application in Indian population under fast and fed conditions.

A novel, selective and sensitive method is developed for simultaneous estimation of canagliflozin and metformin and successfully applied to fast and fed pharmacokinetic studies in healthy Indian volunteers. The current study reports the development, optimization, and validation of liquid chromatography-mass spectrometry (LC-MS/MS) method for simultaneous quantification of canagliflozin and metformin in human plasma using deuterated canagliflozin D4 and metformin D6 as an internal standard (IS). The solid-phase extraction technique was employed where strata X polymeric reverse phase (30 mg-1 cc) SPE cartridges were used for the extraction of analytes and IS from plasma. The ACE 5 C18 column (50 × 4.6 mm, 5µ) was used to chromatograph the prepared samples. The mobile phase consisted of methanol and 5 mM ammonium trifluoroacetate in water, pH 5 (50:50, v/v) at a flow rate of 0.8 mL/min. Detection was performed by positive ion Turbo ion spray in Multiple reaction monitoring (MRM) mode, monitoring the transitions m/z 461.9 â†’ m/z 191.1 and m/z 461.9 â†’ m/z 267.2, for quantification of canagliflozin. The response of canagliflozin fragments m/z 461.9 â†’ m/z 191.1 and m/z 461.9 â†’ m/z 267.2 was combined. Also, for metformin transitions were monitored at m/z 130.0 â†’ m/z 71.1. Full validation of the method was performed according to the United States Food and Drugs Administration (USFDA) guidelines. Linearity was in the range of 24.95-2806.55 ng/mL for canagliflozin and 24.99-3400.72 ng/mL for metformin. The mean extraction recovery of canagliflozin, canagliflozin D4, metformin, and metformin D6 was 77.240, 84.663, 66.747, and 67.449, respectively across four QC levels. This rapid method with the run time of 2.80 min allows the analysis of more than 400 plasma samples per day.

Liquid chromatography-tandem mass spectrometry method for determination of rivaroxaban in human plasma and its application to a pharmacokinetic study.

A high-performance liquid chromatography tandem mass spectrometric method for the determination of Rivaroxaban in human plasma has been developed and validated using Rivaroxaban D4 as an internal standard. The extraction of analyte and internal standard was accomplished by solid phase extraction technique. The method has been validated over a concentration range of 5.96-801 ng/mL. Chromatographic separations were achieved using Gemini C18, 150 mm × 4.6 mm, 5 µm, column eluted at flow rate of 1.5 mL/min with mobile phase (acetonitrile: ammonium acetate buffer (80:20 v/v)). The overall run time of method was about 1.8 min with elution times of Rivaroxaban and its internal standard Rivaroxaban D4 at around 1.18 min. The multiple reaction monitoring transitions were set at 436/145 (m/z) and 440/145 (m/z) for Rivaroxaban and Rivaroxaban D4, respectively. The calibration curves were linear (r2 ≥ 0.99) over the range of 5.96-801 ng/mL with lower limit of quantitation validated at 5.96 ng/mL. Extraction recoveries were >88% for both rivaroxaban and its stable labeled internal standard rivaroxaban D4. The inter-day/between run precisions were ranged from 1.08% to 3.75%, while accuracy ranged from 96.3% to 102%. The presented method was used in pharmacokinetic study in healthy volunteers. Results of incurred sample reanalysis were within the acceptance range of ±20% of original value, for 98.3% of samples reanalyzed. This indicated good assay precision of target analytes in their real matrix at the employed experimental conditions. The applicability of the assay for the determination of the pharmacokinetic parameters was demonstrated.

Development of simultaneous determination of empagliflozin and metformin in human plasma using liquid chromatography-mass spectrometry and application to pharmacokinetics.

A rapid and sensitive liquid chromatography-mass spectrometry method was developed, optimized, and validated for simultaneous quantification of empagliflozin and metformin in human plasma using empagliflozin D4and metformin D6 as an internal standard. Analytes and internal standard were extracted from plasma by optimized solid-phase extraction technique using Strata X polymeric reverse phase (30 mg-1cc) solid-phase extraction cartridges. The prepared samples were chromatographed on Orosil C18 column (150 × 4.6 mm, 3 µ). Separation was done by pumping isocratic mobile phase consisting of methanol and 10 mM ammonium trifluoroacetate (90:10, v/v) in positive ion mode at a flow rate of 0.8 mL/min. The API 3200 liquid chromatography-mass spectrometry system having turbo ion spray as an ion source coupled with Shimadzu Prominence ultrafast liquid chromatography system was operated under the selected reaction monitoring mode. Turbo ion spray ionization was used for mass transition of m/z 468.070/355.100 and m/z 130.072/71.200 for empagliflozin and metformin, respectively. A method was successfully validated for concentration range of 10.09-5013.46 ng/mL for both the analytes and according to the United States Food and Drugs Administration guidelines. The linearity was found to be in the range of 10.09-403.46 ng/mL for empagliflozin and 25.44-5013.46 ng/mL for metformin. The limit of quantification was found to be 10.09 ng/mL for empagliflozin and 25.44 ng/mL for metformin. Intra- and inter-day/between batch precision determination for empagliflozin and metformin, expressed as coefficient of variation were within the acceptance limits and ranged below 13.16%. A short run time of 3.3 min allows analysis of more than 400 plasma samples per day. The developed method was successfully applied to fasting pharmacokinetic study in healthy human volunteers. Results of incurred sample re-analysis were within the acceptance range of ±20% of original value, for 97.2% of samples reanalyzed for empagliflozin and 100% of samples reanalyzed for metformin.

High- performance liquid chromatography method applied to investigate mechanism, kinetics, isotherm, and thermodynamics of bile acid adsorption onto bile acid sequestrants.

The purpose of the study was to develop and validate a high-performance liquid chromatography (HPLC) method which can be further applied to understand the mechanism, kinetics, isotherm, and thermodynamics of bile acid adsorption onto bile acid sequestrants. To investigate these properties a HPLC method was developed using peerless C-8 (150 x 4.6 mm, 5 µm) column with a detection wavelength of 200 nm and run time of about 12.5 min. Bile salts glycocholic (GC), glycochenodeoxycholic (GCDC), and taurodeoxycholic acid (TDC), were used and colesevelam hydrochloride was employed as the bile acid sequestrant. The calibration range was found linear from 10 to 6500 mgL-1 for GC and GCDC and 4to 2400 mg L-1 for TDC. The precision was less than 8.8% and accuracy was found well within the range of 85 to 115%. On treating the data with various established models, it was known that, the adsorption kinetics followed the pseudo second order equation indicating chemisorption mechanism. Equilibrium isotherms revealed that the linear form of Langmuir model was the best fit. The separation factor (RL) calculated revealed that the reaction is favorable and reversible. The positive value of heat of sorption (B) calculated from Temkin model indicated towards the exothermic nature of adsorption. The adsorption energy (E) calculated from Dubinin-Kaganer-Radushkevich model was found to be greater than 8 KJmol-1 conforming chemisorption mechanism. The Gibbs free energy calculated established the affinity of bile salts as TDC > GCDC > GC.

A novel analytical approach towards in-vitro bile acid binding studies to Colesevelam Hydrochloride tablets: An ultra-high performance liquid chromatography tandem mass spectrometric method.

Colesevelam hydrochloride is a bile acid sequestrant used as a low density lipoprotein (LDL) reducing agent in hyperlipidemia with an additional advantage to improve glycemic control in type 2 diabetes patients. The objective of the study was to develop and validate a liquid chromatography tandem mass spectroscopic method for the simultaneous in-vitro estimation of bile acid salts of Glycocholic acid (GC), Glycochenodeoxycholic acid (GCDC) and Taurodeoxycholic acid (TDC) and its application in performing in-vitro binding study with Colesevelam Hydrochloride tablets. The method was developed using C-18 (50 x 4.6 mm, 3 µm) column with detection on negative ion mode and acquisition time of 3.5 min. The calibration range was linear from 0.0002 mM to 0.0065 mM for GC, 0.0002 mM to 0.0065 mM for GCDC and 0.0001 mM to 0.0021 mM for TDC. The precision was less than 3.0% and accuracy was found well within the range of 85 to 115%. The validated method was further applied to conduct in-vitro equilibrium binding study. The data was subjected to Langmuir isotherm and affinity constant (k1) and capacity constant (k2) were calculated.

Comparison of post-operative ICU sedation between dexmedetomidine and propofol in Indian population.

CONTEXT: Critically ill patients requiring mechanical ventilation frequently need sedatives and analgesics to facilitate their care. Dexmedetomidine, a short-acting alpha-2-agonist, possesses anxiolytic, anesthetic, hypnotic, and analgesic properties. AIMS: The objective of this study was to evaluate the efficacy and safety of dexmedetomidine in comparison to propofol in the management of sedation for post-operative intensive care unit (ICU) patients, as a sedative agent. SETTINGS AND DESIGN: Teaching hospital, A phase III, prospective, open, randomized and comparative. MATERIALS AND METHODS: Thirty patients who were ambulatory and who required the post-operative mechanical ventilation or post-operative sedation were enrolled, in which 15 patients received Dexmedetomidine and remaining 15 patients received propofol. All these patients were treated for the period of 8 to 24 h. STATISTICAL ANALYSIS USED: Data were analyzed using Student's t-test and Chi-square test. The value of P < 0.05 was considered as statistically significant. RESULTS: Demographic data were comparable. Pulse rate, respiratory rate and blood pressure were comparable. Depth of sedation and extubation time were similar. To maintain analgesia throughout the study period, patients receiving propofol infusions required significantly more analgesics than patients receiving Dexmedetomidine. CONCLUSIONS: Dexmedetomidine appears to be a safe and acceptable ICU sedative agent when both the clinician's and patient's perspectives are considered.

Development and validation of a highly sensitive LC-MS/MS method for simultaneous quantitation of ethionamide and ethionamide sulfoxide in human plasma: application to a human pharmacokinetic study.

A highly sensitive and specific LC-MS/MS method has been developed for simultaneous quantification of ethionamide and ethionamide sulfoxide in human plasma (300 µL) using prothionamide as an internal standard (IS). Solid-phase extraction was used to extract ethionamide, ethionamide sulfoxide and IS from human plasma. The chromatographic separation of ethionamide, ethionamide sulfoxide and IS was achieved with a mobile phase consisting of 0.1% acetic acid : acetonitrile (20:80, v/v) at a flow rate of 0.50 mL/min on a Peerless Basic C(18) column. The total run time was 3.5 min and the elution of ethionamide, ethionamide sulfoxide and IS occurred at 2.50, 2.18 and 2.68 min, respectively. A linear response function was established for the range of concentrations 25.7-6120 ng/mL (r > 0.998) for ethionamide and 50.5-3030 ng/mL (r > 0.998) for ethionamide sulfoxide. The intra- and inter-day precision values for ethionamide and ethionamide sulfoxide met the acceptance as per FDA guidelines. Ethionamide and ethionamide sulfoxide were stable in battery of stability studies, viz. bench-top, autosampler and freeze-thaw cycles. The developed assay was applied to a pharmacokinetic study in humans.

Human insulin genome sequence map, biochemical structure of insulin for recombinant DNA insulin.

Insulin is a essential molecule for type I diabetes that is marketed by very few companies. It is the first molecule, which was made by recombinant technology; but the commercialization process is very difficult. Knowledge about biochemical structure of insulin and human insulin genome sequence map is pivotal to large scale manufacturing of recombinant DNA Insulin. This paper reviews human insulin genome sequence map, the amino acid sequence of porcine insulin, crystal structure of porcine insulin, insulin monomer, aggregation surfaces of insulin, conformational variation in the insulin monomer, insulin X-ray structures for recombinant DNA technology in the synthesis of human insulin in Escherichia coli.