Effects of Enteric-Coated Formulation of Sodium Bicarbonate on Bicarbonate Absorption and Gastrointestinal Discomfort

Sodium bicarbonate is used as an ergogenic supplement to enhance people's performances in various exercises. This study aimed to evaluate the effects of intestinal delivery of sodium bicarbonate on bicarbonate absorption and associated side effects in an experimental human trial. After preparing and assessing enteric-coated and uncoated sodium bicarbonate tablet formulations, pharmacokinetic analysis and gastrointestinal symptom tests were performed after oral administration in the human body. The dose required to increase blood bicarbonate concentration over 5 mmol∙L-1 for the purpose of improving performance during high-intensity exercise was also determined. Enteric-coated tablet formulation protects sodium bicarbonate under acidic conditions and releases bicarbonate in the intestine. Enteric-coated tablet formulation also reduced the oral dose required to achieve a blood bicarbonate concentration over 5 mmol∙L-1 from 300 mg∙kg-1 of uncoated tablet formulation to 225 mg∙kg-1. Gastrointestinal discomfort was significantly decreased for the group given 225 mg∙kg-1 enteric-coated tablets compared to that given 300 mg∙kg-1 uncoated tablets. These results suggest that enteric-coated tablet formulation could reduce the oral dose required in order to achieve a blood bicarbonate concentration over 5 mmol∙L-1 by 25%, from 300 mg∙kg-1 to 225 mg∙kg-1, along with its ability to reduce gastrointestinal discomfort associated with the dosage.

Enteric-Coated Cologrit Tablet Exhibit Robust Anti-Inflammatory Response in Ulcerative Colitis-like In-Vitro Models by Attuning NFκB-Centric Signaling Axis

Ulcerative colitis (UC) is an inflammatory bowel disease that affects the patients' colorectal area culminating in an inflamed 'leaky gut.' The majority of UC treatments only provide temporary respite leading to its relapse. Therefore, this study investigated the efficacy of the enteric-coated 'Cologrit' (EC) tablet in alleviating UC-like inflammation. Cologrit is formulated using polyherbal extracts that have anti-inflammatory qualities according to ancient Ayurveda scriptures. Phytochemical profiling revealed the presence of gallic acid, rutin, ellagic acid, and imperatorin in Cologrit formulation. Cologrit treatment decreased inflammation in LPS-induced transformed THP-1 macrophages, and TNF-α-stimulated human colorectal (HT-29) cells through the modulation of NFκB activity, IL-6 production, and NFκB, IL-1β, IL-8, and CXCL5 mRNA expression levels. Cologrit also lessened human monocytic (U937) cell adhesion to HT29 cells. Methacrylic acid-ethylacrylate copolymer-coating of the enteric Cologrit tablets (EC) supported their dissolution, and the release of phytochemicals in the small intestine pH 7.0 environment in a simulated gastrointestinal digestion model. Small intestine EC digestae effectively abridged dextran sodium sulfate (2.5% w/v)-induced cell viability loss and oxidative stress in human colon epithelial Caco-2 cells. In conclusion, the enteric-coated Cologrit tablets demonstrated good small intestine-specific phytochemical delivery capability, and decreased UC-like inflammation, and oxidative stress through the regulation of TNF-α/NFκB/IL6 signaling axis.

Oral Delivery of Niclosamide as an Amorphous Solid Dispersion That Generates Amorphous Nanoparticles during Dissolution

Niclosamide is an FDA-approved anthelmintic that is being studied in clinical trials as a chemotherapeutic and broad-spectrum antiviral. Additionally, several other applications are currently in the preclinical stage. Unfortunately, niclosamide is a poorly water soluble molecule, with reduced oral bioavailability, which hinders its use for new indications. Moreover, niclosamide is a poor glass former; in other words, the molecule has a high tendency to recrystallize, and it is virtually impossible to generate a stable amorphous solid employing the neat molecule. Previously, our group reported the development of an amorphous solid dispersion (ASD) of niclosamide (niclosamide ASD) that generates nanoparticles during its dissolution, not only increasing niclosamide's apparent solubility from 6.6 ± 0.4 to 481.7 ± 22.2 µg/mL in fasted state simulated intestinal fluid (FaSSIF) but also its oral bioavailability 2.6-fold in Sprague-Dawley rats after being administered as a suspension. Nevertheless, niclosamide ASD undergoes recrystallization in acidic media, and an enteric oral dosage form is needed for its translation into the clinic. In this work, we further characterized the nanoparticles that generated during the dissolution of the niclosamide ASD. Cryogenic transmission electron microscopy (Cryo-TEM) and wide-angle X-ray scattering (WAXS) revealed that the nanoparticles were amorphous and had a particle size of ~150 nm. The oral dosage forms of niclosamide ASD were formulated using commercial enteric capsules (Capsuline^® and Eudracap^TM) and as enteric-coated tablets. The enteric dosage forms were tested using pH-shift dissolution and acid-uptake tests, using the USP type II dissolution apparatus and the disintegration apparatus, respectively. The capsules exhibited a higher percentage of weight gain, and visual rupture of the Capsuline capsules was observed. Eudracap capsules protected the formulation from the acidic media, but polymer gelling and the formation of a nondispersible plug were noted during dissolution testing. In contrast, enteric-coated tablets protected the formulation from acid ingress and maintained the performance of niclosamide ASD granules during dissolution in FaSSIF media. These enteric-coated tablets were administered to beagle dogs at a niclosamide dose of 75 mg/kg, resulting in plasma concentrations of niclosamide higher than those reported in the literature using solubilized niclosamide at a higher dose (i.e., 100 mg/kg). In summary, an enteric oral dosage form of niclosamide ASD was formulated without hindering the generation of nanoparticles while maintaining the increase in the niclosamide's apparent solubility. The enteric-coated tablets successfully increased the niclosamide plasma levels in dogs when compared to a niclosamide solution prepared using organic solvents.

Pharmacokinetics and food impact assessment of ademetionine enteric-coated tablet as an endogenous substance drug in healthy Chinese volunteers

WHAT IS KNOWN AND OBJECTIVES

Ademetionine 1,4-Butanedisulfonate (SAMe) enteric-coated tablets are widely used for treatment of pre-cirrhotic and cirrhotic intrahepatic cholestasis, as well as intrahepatic cholestasis of pregnancy (ICP), but incomplete clinical data and interference from endogenous substances pose numerous challenges for clinical trial of ademetionine. The objective of this study was to evaluate the pharmacokinetic profile of SAMe enteric-coated tablets and to assess its food impact and safety in healthy Chinese subjects.

METHODS

A randomized, open-label, single-dose study was carried out to determine the pharmacokinetics of SAMe enteric-coated tablets administered in both fasted and postprandial conditions. Baseline collection and data adjustment were required to reduce the effect of endogenous substances. Relevant pharmacokinetic data from subjects administered the reference formulation will be disclosed and utilized in this thesis.

RESULTS

Twenty-four subjects with a body mass index (BMI) of 19-24 kg/m² were enrolled in the study and all completed the trial. The impact of food on the drug was noticeable, with faster absorption in the fasting group (T_max , 4.50 ± 1.07 and 7.50 ± 1.58 for the fasting and postprandial groups, respectively) but higher exposure in the postprandial group (AUC_0-inf , 4021.02 ± 3377.13 and 5087.28 ± 3539.26 for the fasting and postprandial groups, respectively). No serious adverse effects were observed in the fasted and postprandial conditions.

WHAT IS NEW AND CONCLUSIONS

The pharmacokinetic profile of SAMe enteric-coated tablets in healthy Chinese subjects was partially complemented in this study. SAMe enteric-coated tablets showed promising safety in fasted and postprandial conditions. However, the impact of food on the drug was significant and might access to the absorption site and affect biochemical reactions.

Pharmacokinetics, Bioequivalence, and Safety Studies of Pantoprazole Sodium Enteric-Coated Tablets in Healthy Subjects

This study aimed to evaluate the bioequivalence of 2 pantoprazole sodium enteric-coated tablet formulations, a generic formulation and a branded formulation, and to investigate their pharmacokinetic and safety profiles. The study was designed as a single-center, randomized, open-label, single-dose, dual-period, and 2-sequence crossover trial, and was divided into fasting and postprandial human bioequivalence trials. In the first trial, 36 subjects were fasted overnight before they were given generic or branded tablets (during 2 separate administration periods). Separately, 42 subjects were provided a high-fat meal 1 hour before the drugs were administered. Blood specimens of each subject were obtained up to 24 hours after drug administration. No significant differences were observed between the pharmacokinetic profiles of the generic and branded pantoprazole sodium enteric-coated tablets. Bioequivalence was evaluated using 90% confidence intervals for the ratio of test/reference log area under the concentration-time curve over 24 hours, log area under the concentration-time curve to infinity (AUC_0-∞ ), and log peak concentration (C_max ). The 90% confidence intervals of the least squares geometric mean ratio of C_max , area under the concentration-time curve from time zero to the last measurable concentration (AUC_0-t ), and AUC_0-∞ of 36 subjects in the fasting trial and of 40 of 41 subjects in the postprandial trial (C_max [41], AUC_0-t [41], and AUC_0-∞ [40]) were in accordance with the bioequivalence criteria. No severe adverse effects were detected. The generic and branded pantoprazole sodium enteric-coated tablets were considered bioequivalent with similar safety profiles.

Determination of Eudragit® L100 in an Enteric-Coated Tablet Formulation Using Size-Exclusion Chromatography with Charged-Aerosol Detection

Eudragit^® L100 is a commonly used polymer in a coating layer of modified-release drug formulation to prevent drug release in the stomach. The amount of Eudragit^® L100 in the formula determines the dissolution profile of drug at its release medium. Hence, its quantification in reference product will facilitate the formulation of a bioequivalent drug product. Some analytical methods including size-exclusion chromatography (SEC) have been reported for characterization of Eudragit^® L100 either as single component or its conjugate with the enzyme, but none for its quantification in drug formulation. In this work, an SEC method with charged-aerosol detection (CAD) was developed for determination of Eudragit^® L100 in an enteric-coated tablet formulation using Waters Ultrahydrogel 1000 and Waters Ultrahydrogel 120 columns in series. The mobile phase was a mixture of 90:10 (v/v) 44.75 mM aqueous ammonium acetate buffer, pH 6.6 and acetonitrile pumped at a constant flow rate of 0.8 mL/min in isocratic mode. The method was validated for specificity, working range, limit of detection (LOD), limit of quantification (LOQ), accuracy and precision. The method was shown to be specific for Eudragit^® L100 against the diluent (mobile phase) and placebo of a coating layer for the tablet. A good correlation coefficient (r = 0.9997) of CAD response against Eudragit^® L100 concentration from 0.1⁻1.0 mg/mL was obtained using polynomial regression. LOD and LOQ concentrations were 0.0015 and 0.0040 mg/mL, respectively. The mean recovery of Eudragit^® L100 was in the range of 88.0⁻91.1% at three levels of working concentration: 50%, 100% and 150%. Six replicated preparations of samples showed good precision of the peak area with % relative standard deviation (RSD) 2.7. In conclusion, the method was suitable for quantification of Eudragit^® L100 in an enteric-coated tablet formulation.