Stability Evaluation and Pharmacokinetic Profiling of Vepdegestrant in Rodents Using Liquid Chromatography-Tandem Mass Spectrometry.

Vepdegestrant (formerly ARV-471), a novel proteolysis-targeting chimera (PROTAC), targets estrogen receptor alpha (ERα) for degradation, offering a promising option to treat advanced ER-positive breast cancer. We developed and validated a sensitive and rapid liquid chromatography-tandem mass spectrometry method to quantify vepdegestrant in rodent plasma using bavdegalutamide (formerly ARV-110) as an internal standard. Plasma samples were prepared with protein precipitation using acetonitrile and analyzed using reverse-phase C18 columns and a mobile phase of 10 mM ammonium formate in distilled water and acetonitrile. The method demonstrated linearity from 1 to 1000 ng/mL in mouse and rat plasma, meeting all validation criteria, and successfully applied to in vivo and in vitro studies. Pharmacokinetic analysis revealed low-to-moderate clearance (313.3, 1053 mL/h/kg) and oral bioavailability (17.91, 24.12%) of vepdegestrant in mice and rats, respectively. It was unstable in buffer solutions across pH 2-10 and in phosphate-buffered saline (pH 7.4), likely due to adsorption, but remained stable in mouse and rat plasma at varying temperatures. In liver microsomes, vepdegestrant exhibited moderate stability in rats but was stable in mice, dogs, and humans. These findings enhance the understanding of pharmacokinetic properties of vepdegestrant supporting further development of PROTAC drugs.

Mesoporous Silica Nanoparticles as a Potential Nanoplatform: Therapeutic Applications and Considerations.

With advances in nanotechnology, nanoparticles have come to be regarded as carriers of therapeutic agents and have been widely studied to overcome various diseases in the biomedical field. Among these particles, mesoporous silica nanoparticles (MSNs) have been investigated as potential nanocarriers to deliver drug molecules to various target sites in the body. This review introduces the physicochemical properties of MSNs and synthesis procedures of MSN-based nanoplatforms. Moreover, we focus on updating biomedical applications of MSNs as a carrier of therapeutic or diagnostic cargo and review clinical trials using silica-nanoparticle-based systems. Herein, on the one hand, we pay attention to the pharmaceutical advantages of MSNs, including nanometer particle size, high surface area, and porous structures, thus enabling efficient delivery of high drug-loading content. On the other hand, we look through biosafety and toxicity issues associated with MSN-based platforms. Based on many reports so far, MSNs have been widely applied to construct tissue engineering platforms as well as treat various diseases, including cancer, by surface functionalization or incorporation of stimuli-responsive components. However, even with the advantageous aspects that MSNs possess, there are still considerations, such as optimizing physicochemical properties or dosage regimens, regarding use of MSNs in clinics. Progress in synthesis procedures and scale-up production as well as a thorough investigation into the biosafety of MSNs would enable design of innovative and safe MSN-based platforms in biomedical fields.

Combined Application of Prototype Ultrasound and BSA-Loaded PLGA Particles for Protein Delivery.

PURPOSE: To develop an in vitro culture system for tissue engineering to mimic the in vivo environment and evaluate the applicability of ultrasound and PLGA particle system. METHODS: For tissue engineering, large molecules such as growth factors for cell differentiation should be supplied in a controlled manner into the culture system, and the in vivo microenvironment need to be reproduced in the system for the regulation of cellular function. In this study, portable prototype ultrasound with low intensity was devised and tested for protein release from bovine serum albumin (BSA)-loaded poly(lactic-co-glycolic acid) (PLGA) particles. RESULTS: BSA-loaded PLGA particles were prepared using various types of PLGA reagents and their physicochemical properties were characterized including particle size, shape, or aqueous wetting profiles. The BSA-loaded formulation showed nano-ranged size distribution with optimal physical stability during storage period, and protein release behaviors in a controlled manner. Notably, the application of prototype ultrasound with low intensity influenced protein release patterns in the culture system containing the BSA-loaded PLGA formulation. The results revealed that the portable ultrasound set controlled by the computer could contribute for the protein delivery in the culture medium. CONCLUSIONS: This study suggests that combined application with ultrasound and protein-loaded PLGA encapsulation system could be utilized to improve culture system for tissue engineering or cell regeneration therapy.

Pharmacokinetics and diuretic effect of furosemide after single intravenous, oral tablet, and newly developed oral disintegrating film administration in healthy beagle dogs.

BACKGROUND: Furosemide, a diuretic that acts on the loop of Henle, is commonly used to treat congestive heart failure in veterinary medicine. Some owners have difficulty in administering oral tablet medication to animal patients, which leads to noncompliance, especially during long-term administration. Oral disintegrating film (ODF) has the advantages of easy administration via a non-invasive route, rapid dissolution, and low suffocating risk. The objective of this study was to research the pharmacokinetic (PK) profiles and diuretic effect of furosemide after intravenous (IV), orally uncoated tablet (OUT), and newly developed ODF administration in healthy beagle dogs. In this study, a furosemide-loaded ODF (FS-ODF) formulation was developed and five beagle dogs were administered a single dose (2 mg/kg) of furosemide via each route using a cross-over design. RESULTS: The most suitable film-forming agent was sodium alginate; thus, this was used to develop an ODF for easy drug administration. No significant differences were detected in the PK profiles between OUT and FS-ODF. In the blood profiles, the concentration of total protein was significantly increased compared to the baseline (0 h), whereas no significant difference was detected in the concentration of creatinine and hematocrit compared to the baseline. FS-ODF resulted in a similar hourly urinary output to OUT during the initial 2 h after administration. The urine specific gravity was significantly decreased compared to the baseline in each group. The peak times of urine electrolyte (sodium and chloride) excretion per hour were 1 h (IV), 2 h (OUT), and 2 h (FS-ODF). CONCLUSIONS: These results suggest that the PK/PD of furosemide after administration of newly developed FS-ODF are similar to those of OUT in healthy dogs. Therefore, the ODF formulation has the benefits of ease and convenience, which would be helpful to owners of companion animals, such as small dogs (< 10 kg), for the management of congestive heart failure.

Extracellular Vesicles: The Next Frontier in Regenerative Medicine and Drug Delivery.

Extracellular vesicles (EVs) are nanosized membrane particles secreted by cells to convey intercellular information. In recent years, EVs have enticed scientists owing to their prevalent distribution, enormous possibility as therapeutic aspirants, and probable roles as disease biomarkers. As natural transporters in the endogenous communication system, they play a role in protein, lipid, miRNA, mRNA, and DNA transport. In this chapter, we recapitulate the roles of EVs in the vast field of regenerative medicine. This summary mainly describes the potential roles of EVs in the regeneration of extensively studied organs or tissues, such as the heart, kidney, lung, liver, skin, and hair. Furthermore, EV can also transport drugs and corroborate their uptake by target cells through endocytosis; therefore, this chapter also highlights the use of EVs in the field of drug delivery.

Enhanced Solubility, In-Vitro Dissolution and Lipase Inhibition of a Self-Nanoemulsifying Drug Delivery System Containing Orlistat.

The aim of this work was to prepare and assess a self-nanoemulsifying drug delivery system (SNEDDS) containing water-insoluble orlistat that was used for the inhibition of lipase activity in gastrointestinal lumen. The pseudo-ternary phase diagram, composed of orlistat and medium chain triglycerides (MCT) as oil phase and Cremophor EL as surfactant, was made for the confirmation of giving SNEDDS preconcentrate. The physical state, particle size dispersed in water, dissolution and lipase inhibition of SNEDDS preconcentrates were investigated. The appointed SNEDDS preconcentrates in the pseudo-ternary phase diagram showed no endothermic peak of orlistat and a liquid state. The particle sizes of SNEDDS dispersed with water were uniform and in the range of <200 nm. In the dissolution test, the liquid SNEDDS preconcentrate and solid state mixture exhibited 90.89±2.03% versus 22.42±3.71% at 60 min., respectively, whereas the raw orlistat showed no significant dissolution rate. The SNEDDS preconcentrate showed a lipase inhibition of 92.42±1.58% until 60 min., with no significant inhibition activity of orlistat. Therefore, the SNEDDS preconcentrate presented in this work solubilized orlistat and increased its dissolution rate, and resulted in sufficient inhibitory action on lipase.

Preparation, Characterization, and In Vitro Release of Chitosan-Ecabet Electrolyte Complex for the Mucosal Delivery.

Ecabet has a mucosal protection and anti-Helicobacter pylori effect only by local action in the gastric mucous layer, due to an extremely poor absorption into the systemic blood circulation. The aim of the present work was to develop chitosan-ecabet electrolyte complex (ChE) for the enhanced mucosal drug delivery. ChEs were prepared with various ecabet-chitosan concentration ratios. Entrapment efficiency (%), sedimentation volume (%), transmission electron microscopy (TEM), FT-IR spectrum, and drug release were investigated. ChEs were prepared by the simple mixing method in a pH-adjusted solution based on the electrostatic interaction between the sulfonate (negatively charged) group from ecabet and the amine (positively charged) group from chitosan. Sedimentation volume and entrapment efficiency at the same concentration of ecabet sodium with that of chitosan resulted in 53.6% and 86.75%, respectively, suggesting a high degree of forming complex. In TEM images, the complex was approximately 200 nm in particle size and had loosely entangled particles. Forming complex of ChEs was supported by new bands appearance in the FT-IR spectrum. In the drug release study using dialysis membrane sac, ChEs showed a sustainable release up to 80% during 12 h as compared to ecabet sodium suspension at pH 1.2 medium. Based on the results of this work, ChE would be a promising drug delivery system for gastric mucosa.

Preparation and Characterization of Celecoxib Nanosuspension Using Bead Milling.

The aim of this study is to develop nanosuspension for improved dissolution of poorly water-soluble celecoxib. We first prepared coarse suspension of celecoxib with Tween 80 and hydroxypropyl methylcellulose as stabilizers, and then fabricated nanosuspension using the bead milling technique. Depending on milling time, the physical properties of nanosuspension were evaluated by photon correlation spectroscopy (e.g., particle size and distribution) and scanning electron microscopy (SEM) (e.g., morphology). As results, the mean size of crystalline celecoxib particles was highly reduced (368.1±14.5 nm) as milling process proceeded comparing to celecoxib powder (6.5±1.0 µm). Morphology of milled celecoxib particles has changed considerably from bar-shape or plate-shape to needle-shape due to a high energy caused by milling. In the dissolution test, the celecoxib nanosuspension showed an improved dissolution profile at pH 1.2 compared to celecoxib powder (less than 1%). In contrast, 53.4% of celecoxib in nanosuspension was dissolved up to 30 minutes, demonstrating improved dissolution of celecoxib. Taken together, bead-milled nanosuspension could be an effective strategy that can improve the dissolution and bioavailability.

Preparation of Silica Microparticles as Volatile Material Carrier and Their Sustained-Release Property.

The aim of this study is to develop an effective delivery system (silica microparticles) encapsulating volatile essential oil (EO) by multiple emulsification process and sol-gel method. Depending on critical materials (Pluronic P123 and HPC) and process parameter (drying temperature), silica microparticles were prepared and evaluated. As results, the amount of EO inside microparticles increased in polymer-dependent manners. On the other hand, the amount of EO was reduced as drying temperature increased. Based on these data, the condition fabricating silica microparticles was optimized: drying temperature (25 °C), Pluronic P123 (1.2%) and HPC (1.2%). The size and morphology of microparticles were observed by scanning electron microscopy. Also, the loadings and release profiles of EO in these particles were quantitatively analyzed by HPLC. Optimized silica microparticles showed the high encapsulation efficiency (32.7%) and sustained-release profiles of EO for 3 days. Taken together, silica microparticles are effective carrier for encapsulating volatile materials and providing sustained-release.

Comparative Assessment of Biological Activities of Mistletoes for Cosmetic Applications: Viscum Album Var. Coloratum (Kom.) Ohwi and Loranthus Tanakae Franch. & Sav.

Mistletoes, hemiparasites, contain many components with various biological activities and have been used in cosmetics industry. Loranthacease (1,000 species) and Viscaceae (550 species) have the most dominant species in mistletoes (nearly 1,600 species). It can be expected that the biological activities vary from species to species; therefore, we have tested Viscum album var. coloratum (Kom.) Ohwi (belonging to Santalaceae) and Loranthus tanakae Franch. & Sav. (belonging to Loranthacease) for a comparative study of their cosmetic properties, including antioxidant, antimelanogenic, and antiwrinkle activities. As results, the ethanol extract of L. tanakae had higher phenolic content and showed effective antioxidant activity and elastase inhibition. Meanwhile, the ethanol extract of V. album more effectively inhibited tyrosinase. Comparing with ethanol extracts, the water extracts of both mistletoes showed lower biological efficacy than the ethanol extracts or no significant effect. Thus, these results show that different extracts of mistletoe have different levels of biological activities, presumably because of the differences in their phytochemical profiles and because of the different extraction methods used.

Removing Control of Cyclodextrin-Drug Complexes Using High Affinity Molecule.

Nanostructured supramolecular assemblies with hydrophobic cavities are used for improving the solubility, bioavailability, and stability of poorly water soluble drugs. In particular, host-guest inclusion using 2-hydroxypropyl-beta-cyclodextrin (HP-ß-CD) is a typical approach in the pharmaceutical field. In this study, celecoxib (CXB), a cyclooxygenase-2 selective nonsteroidal anti-inflammatory drug (NSAID), was used as the model drug (guest material) and effectively incorporated into HP-ß-CD (host material). After forming a complete complex of HP-ß-CD and CXB, 1-adamantylamine (ADA) was used to allow CXB to be released from the HP-ß-CD in a concentration-dependent manner. This was revealed from Fourier-transform infrared spectroscopy and drug dissolution studies. Notably, the use of ADA, which is a high-affinity guest molecule, with cyclodextrin accelerated the removal of CXB from the host material through the exchange of guest molecules. Taken together, the host-guest based approach using a second guest molecule is useful for regulating on-demand drug release and could therefore be a potential tool for biomedical applications.

Improved Dissolution and Oral Bioavailability of Celecoxib by a Dry Elixir System.

The purpose of this study was to develop and evaluate a dry elixir (DE) system for enhancing the dissolution rate and oral bioavailability of celecoxib. DE system has been used for improving solubility, oral bioavailability of poorly water-soluble drugs. The encapsulated drugs or solubilized drugs in the matrix are rapidly dissolved due to the co-solvent effect, resting in both an enhanced dissolution and bioavailability. DEs containing celecoxib were prepared by spray-drying method and characterized by morphology, drug/ethanol content, drug crystallinity, dissolution rate and oral bioavailability. The ethanol content and drug content in DE system could be easily altered by controlling the spraydrying conditions. The dissolution profile of celecoxib from DE proved to be much higher than that of celecoxib powder due to the nano-structured matrix, amorphous state and encapsulated ethanol. The bioavailability of celecoxib from DEs was compared with celecoxib powder alone and commercial product (Celebrex®) in rats. In particular, blood concentrations of celecoxib form DE formulation were much greater than those of native celecoxib and market product. The data demonstrate that the DE system could provide an useful solid dosage form to enhance the solubility, dissolution rate and oral bioavailability of celecoxib.

Cefdinir Solid Dispersion Composed of Hydrophilic Polymers with Enhanced Solubility, Dissolution, and Bioavailability in Rats.

The aim of this work was to develop cefdinir solid dispersions (CSDs) prepared using hydrophilic polymers with enhanced dissolution/solubility and in vivo oral bioavailability. CSDs were prepared with hydrophilic polymers such as hydroxypropyl-methylcellulose (HPMC; CSD1), carboxymethylcellulose-Na (CMC-Na; CSD2), polyvinyl pyrrolidone K30 (PVP K30; CSD3) at the weight ratio of 1:1 (drug:polymer) using a spray-drying method. The prepared CSDs were characterized by aqueous solubility, differential scanning calorimetry (DSC), powder X-ray diffraction (p-XRD), scanning electron microscopy (SEM), aqueous viscosity, and dissolution test in various media. The oral bioavailability of CSDs was also evaluated in rats and compared with cefdinir powder suspension. The cefdinir in CSDs was amorphous form, as confirmed in the DSC and p-XRD measurements. The developed CSDs commonly resulted in about 9.0-fold higher solubility of cefdinir and a significantly improved dissolution profile in water and at pH 1.2, compared with cefdinir crystalline powder. Importantly, the in vivo oral absorption (represented as AUCinf) was markedly increased by 4.30-, 6.77- and 3.01-fold for CSD1, CSD2, and CSD3, respectively, compared with cefdinir suspension in rats. The CSD2 prepared with CMC-Na would provide a promising vehicle to enhance dissolution and bioavailability of cefdinir in vivo.

Vitamin D Receptor-Mediated Upregulation of CYP3A4 and MDR1 by Quercetin in Caco-2 cells.

To examine whether quercetin interacts with vitamin D receptor, we investigated the effects of quercetin on vitamin D receptor activity in human intestinal Caco-2 cells. The effects of quercetin on the expression of the vitamin D receptor target genes, vitamin D3 24-hydroxylase, cytochrome P450 3A4, multidrug resistance protein 1, and transient receptor potential vanilloid type 6 were measured using quantitative polymerase chain reaction. The vitamin D receptor siRNA was used to assess the involvement of the vitamin D receptor. Vitamin D receptor activation using a vitamin D responsive element-mediated cytochrome P450 3A4 reporter gene assay was investigated in Caco-2 cells transfected with human vitamin D receptor. We also studied the magnitude of the vitamin D receptor activation and/or synergism between 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3] and quercetin-like flavonoids. Slight but significant increases in the mRNA expression of cytochrome P450 3A4, vitamin D3 24-hydroxylase, multidrug resistance protein 1, and transient receptor potential vanilloid type 6 were observed after 3 days of continual quercetin treatment. The silencing effect of vitamin D receptor by vitamin D receptor siRNA in Caco-2 cells significantly attenuated the induction of the vitamin D receptor target genes. Moreover, quercetin significantly enhanced cytochrome P450 3A4 reporter activity in Caco-2 cells in a dose-dependent manner, and the expression of exogenous vitamin D receptor further stimulated the vitamin D receptor activity. Quercetin-like flavonoids such as kaempferol stimulated the vitamin D receptor activity in a manner similar to that seen with quercetin. Taken together, the data indicates that quercetin upregulates cytochrome P450 3A4 and multidrug resistance protein 1 expression in Caco-2 cells likely via a vitamin D receptor-dependent pathway.

Influence of polyvinylpyrrolidone quantity on the solubility, crystallinity and oral bioavailability of fenofibrate in solvent-evaporated microspheres.

The objective of this study is to explore the influence of polyvinylpyrrolidone (PVP) quantity on the solubility, crystallinity and oral bioavailability of poorly water-soluble fenofibrate in solvent-evaporated microspheres. Numerous microspheres were prepared with fenofibrate, sodium lauryl sulphate (SLS) and PVP using the spray-drying technique. Their aqueous solubility, dissolution, physicochemical properties and pharmacokinetics in rats were assessed. The drug in the solvent-evaporated microspheres composed of fenofibrate, PVP and SLS at the weight ratio of 1:0.5:0.25 was not entirely changed to the amorphous form and partially in the microcrystalline state. However, the microspheres at the weight ratio of 1:4:0.25 provided the entire conversion to the amorphous form. The latter microspheres, with an improvement of about 115 000-fold in aqueous solubility and 5.6-fold improvement in oral bioavailability compared with the drug powder, gave higher aqueous solubility and oral bioavailability compared with the former. Thus, PVP quantity played an important role in these properties of fenofibrate in the solvent-evaporated microspheres.

Novel piroxicam-loaded nanospheres generated by the electrospraying technique: physicochemical characterisation and oral bioavailability evaluation.

To determine if a novel electrospraying technique could be applied to an oral drug delivery system for improving the solubility and oral bioavailability of poorly water-soluble piroxicam; the nanospheres were generated with drug and polyvinylpyrrolidone (PVP) using electrospraying technique; and their physicochemical properties, solubility, release and pharmacokinetics were evaluated in comparison with piroxicam powder. All nanospheres had significantly increased drug solubility and dissolution rates in comparison with the drug powder. In particular, the nanosphere composed of piroxicam and PVP at a weight ratio of 2:8 gave about 600-fold higher solubility, 15-fold higher release rate and 3-fold higher AUC in comparison to piroxicam powder, leading to significantly enhanced oral bioavailability in rats, due to the mingled effect of nanonisation along with transformation to the amorphous state. Thus, this electrospraying technique can be utilised to produce a novel oral nanosphere delivery system with enhanced solubility and oral bioavailability for poorly water-soluble piroxicam.

Enhanced Cellular Uptake and Pharmacokinetic Characteristics of Doxorubicin-Valine Amide Prodrug.

In this study, we synthesized the valine (Val)-conjugated amide prodrug of doxorubicin (DOX) by the formation of amide bonds between DOX and Val. The synthesis of the DOX-Val prodrug was identified by a proton nuclear magnetic resonance (¹H-NMR) assay. In the MCF-7 cells (human breast adenocarcinoma cell; amino acid transporter-positive cell), the cellular accumulation efficiency of DOX-Val was higher than that of DOX according to the flow cytometry analysis data. Using confocal laser scanning microscopy (CLSM) imaging, it was confirmed that DOX-Val as well as DOX was mainly distributed in the nucleus of cancer cells. DOX-Val was intravenously administered to rats at a dose of 4 mg/kg, and the plasma concentrations of DOX-Val (prodrug) and DOX (formed metabolite) were quantitatively determined. Based on the systemic exposure (represented as area under the curve (AUC) values) of DOX-Val (prodrug) and DOX (formed metabolite), approximately half of DOX-Val seemed to be metabolized into DOX. However, it is expected that the remaining DOX-Val may exert improved cellular uptake efficiency in cancer cells after its delivery to the cancer region.

Clopidogrel Napadisilate Monohydrate Loaded Surface-Modified Solid Dispersion: Physicochemical Characterization and in Vivo Evaluation.

To develop a novel solid dispersion of clopidogrel napadisilate monohydrate (CNM) with improved stability and oral bioavailability, surface-modified solid dispersions were prepared by spray-drying using water as a solvent, Tween 80 as a surfactant, and hydroxypropylmethyl cellulose (HPMC) as a hydrophilic polymer, and optimized according to drug solubility. Its solid-state characterization was evaluated by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC). The stability study was performed at 50°C/75% RH over a period of 6 weeks. Its dissolution profiles and oral bioavailability in rats were also compared with that of CNM and clopidogrel bisulfate (CB). The solid dispersion, composed of CNM/HPMC/Tween80 at a weight ratio of 10/2.5/2.5, in which CNM was in the crystalline state, increased the drug solubility approximately 4.6-fold. It showed a significantly better dissolution profile than that of CNM in all the dissolution media, and gave either similar or higher dissolution compared to that of CB. This solubility and dissolution enhancement was attributed to improved wetting and solubilization of CNM crystals due to hydrophilic carriers attached on the drug surface. It had excellent stability, thereby addressing the stability problem of CB powder. Furthermore, it increased the area under curve (AUC) values by about 4-fold and 1.6-fold compared to CNM and CB, respectively, suggesting that it improved the oral bioavailability of the drug in rats. Thus, this solid dispersion system prepared with water, HPMC and Tween 80 can be used to enhance the bioavailability of CNM as well as to solve the stability problem of CB.

Pharmacokinetics, pharmacodynamics and food effect of LB30870, a novel direct thrombin inhibitor, after single oral doses in healthy men.

1. The safety, tolerability, pharmacokinetics, pharmacodynamics, and food effect of LB30870, a new selective thrombin inhibitor, were studied in 16 healthy men. 2. A double-blind, placebo-controlled single ascending dose study was done at oral doses of 5, 15, 30, 60, 120, and 240 mg under fasting conditions. An open, randomized, balanced cross-over food effect study was done at 60 mg dose. Plasma and urinary concentrations were measured up to 48 h post-dose. Coagulation and thrombin activity markers were measured at selected time points. 3. Cmax of LB30870 was at 1.3-3.0 h post-dose with a mean apparent terminal half-life (t1/2) of 2.8-4.1 h. AUC after doses above 15 mg appeared greater than dose-proportional. In fed state, AUC showed 80% reduction relative to fasting condition. 4. At doses 60 and 120 mg, peak activated partial thromboplastin time (aPTT) increased by 1.5- and 2-fold, respectively, from baseline. The aPTT and international normalized ratio (INR) were concentration-dependent, with less within-individual variability than ecarin clotting time (ECT), prothrombin time (PT), or thrombin time (TT). 5. Single oral doses of LB30870 up to 240 mg were well tolerated. The food effect must be overcome if LB30870 is to be used as an oral anti-coagulant.