Biopharmaceutical Characteristics Research Articles

Design and biopharmaceutical preclinical characterisation of a new thermosensitive hydrogel for the removal of gastric polyps

Background and AimsSubmucosal injection agents are widely used solutions in gastric polyp resection techniques. Currently, many different solutions are used in clinical practice, but most are not authorised for this use or are not biopharmaceutical characterised. The objective of this multidisciplinary work is to test the efficacy of a novel thermosensitive hydrogel designed specifically for this indication. MethodsA mixture design of various components (Pluronic®, hyaluronic acid and sodium alginate) was carried out to select the combination with optimal properties for this use. Three final thermosensitive hydrogels were selected on which biopharmaceutical characterisation was performed and stability and biocompatibility were analysed. Efficacy in maintaining elevation was tested ex vivo on pig mucosa and in vivo in pigs ResultsThe mixture design allowed selection of the ideal combinations of agents for the characteristics sought. The thermosensitive hydrogels studied showed high values of hardness and viscosity at 37 °C, maintaining good syringeability. One of them demonstrated superiority in maintaining polyp elevation in the ex vivo assay and non-inferiority in the in vivo assay. ConclusionThe thermosensitive hydrogel specifically designed for this use is promising both for its biopharmaceutical characteristics and for its demonstrated efficacy. This study lays the foundation for evaluating the hydrogel in humans.

Comparative Analysis of Physical and Chemical Properties of Differently Obtained Zn-Methionine Chelate with Proved Antibiofilm Properties (Part II).

The previously demonstrated activity of aqueous solutions of methionine and zinc salts against biofilms of uropathogenic bacteria prompted us to investigate the structure and properties of zinc methionine complex obtained from such solutions. The paper presents the analysis results of zinc coordination complexes with methionine obtained by synthesis (0.034 mol of L-methionine, 0.034 mol of NaOH, 40 mL of H2O, 0.017 mol ZnSO4, 60 °C) and simple crystallization from water solution (25 mL of a solution containing 134 mmol/L L-methionine, 67 mmol/L ZnSO4, pH = 5.74, I = 0.37 mmol/L, crystallization at room temperature during more than two weeks). IR spectral analysis and X-ray diffraction showed the structural similarity of the substances to each other, in agreement with the data described in the literature. DSC confirmed the formation of a thermally stable (in the range from -30 °C to 180 °C) chelate compound in both cases and indicated the possible retention of the polymorphic two-dimensional structure inherent in L-methionine with the temperature of phase transition 320 K. The crystallized complex had better solubility in water (100 to 1000 mL per 1.0 g) contra the synthesized analog, which was practically insoluble (more than 10 000 mL per 1.0 g). The results of the solubility assessment, supplemented by the results of the dispersion analysis of solutions by the dynamic light scattering method indicated the formation of zinc-containing nanoparticles (80 nm) in a saturated water solution of a crystallized substance, suggesting the crystallized substance may have higher bioavailability. We predicted a possibility of the equivalent existence of optically active cis and trans isomers in methionine-zinc solutions by the close values of formation enthalpy (-655 kJ/mol and -657 kJ/mol for cis and trans forms, respectively) and also illustrated by the polarimetry measurement results (∆α = 0.4°, pH = 5.74, C(Met) = 134 mmol/L; the concentration of metal ion gradually increased from 0 to 134 mmol/L). The obtained results allowed us to conclude that the compound isolated from the solution is a zinc-methionine chelate with the presence of sulfate groups and underline the role of the synthesis route for the biopharmaceutical characteristics of the resulting substance. We provided some quality indicators that it may be possible to include in the pharmacopeia monographs.

Influence of Co-amorphization on the Physical Stability and Dissolution Performance of an Anthelmintic Drug Flubendazole.

In this work, the co-amorphization approach was applied to flubendazole (FluBZ), resulting in the formation of two novel solid forms of FluBZ with l-phenylalanine (Phe) and l-tryptophan (Trp). A variety of physicochemical techniques have been used to describe new systems, including powder X-ray diffraction, thermal methods, infrared spectroscopy, and scanning electron microscopy. Co-amorphization has been shown to suppress crystallization tendency and considerably increase the shelf-life storage of amorphous flubendazole solid across a wide range of relative humidities. The dissolution behavior of the amorphous forms in biorelevant media at pH = 1.6, pH = 6.5, and 37 °C has been studied in terms of Cmax (maximum FluBZ concentration), Tmax (time to attain peak drug concentration), and AUC (concentration area under the curve during dissolution). At pH = 6.5, a continuous supersaturation and the highest AUC value of all examined systems were observed for the FluBZ-Phe (1:1) system. The phase solubility diagrams revealed that the reason for the better dissolution performance of FluBZ-Phe (1:1) at pH = 6.5 is a complexation between the components in a solution. This work highlights the applicability of co-amorphous systems in improving the physical stability and dissolution performance of drug compounds with poor biopharmaceutical characteristics.

A mechanistic study on the cellular uptake, intracellular trafficking, and antisense gene regulation of bottlebrush polymer-conjugated oligonucleotides.

We have developed a non-cationic transfection vector in the form of bottlebrush polymer-antisense oligonucleotide (ASO) conjugates. Termed pacDNA (polymer-assisted compaction of DNA), these agents show improved biopharmaceutical characteristics and antisense potency in vivo while suppressing non-antisense side effects. Nonetheless, there still is a lack of the mechanistic understanding of the cellular uptake, subcellular trafficking, and gene knockdown with pacDNA. Here, we show that the pacDNA enters human non-small cell lung cancer cells (NCI-H358) predominantly by scavenger receptor-mediated endocytosis and macropinocytosis and trafficks via the endolysosomal pathway within the cell. The pacDNA significantly reduces a target gene expression (KRAS) in the protein level but not in the mRNA level, despite that the transfection of certain free ASOs causes ribonuclease H1 (RNase H)-dependent degradation of KRAS mRNA. In addition, the antisense activity of pacDNA is independent of ASO chemical modification, suggesting that the pacDNA always functions as a steric blocker.

Strategic application of a mixed polymeric micellar solid dispersion system to domperidone for improved biopharmaceutical characteristics

Strategic application of a mixed polymeric micellar solid dispersion system to domperidone for improved biopharmaceutical characteristics

Repurposing Disulfiram as an Antimicrobial Agent in Topical Infections.

Antimicrobial drugs applied topically offer several advantages. However, the widespread use of antibiotics has led to increasing antimicrobial resistance. One interesting approach in the drug discovery process is drug repurposing. Disulfiram, which was originally approved as an anti-alcoholism drug, offers an attractive alternative to treat topical multidrug resistance bacteria in skin human infections. This study aimed to evaluate the biopharmaceutical characteristics of the drug and the effects arising from its topical application in detail. Microdilution susceptibility testing showed antibacterial activity against Gram-positive bacteria Staphylococcus aureus and Streptococcus pyogenes. Dermal absorption revealed no permeation in pig skin. The quantification of the drug retained in pig skin demonstrated concentrations in the stratum corneum and epidermis, enough to treat skin infections. Moreover, in vitro cytotoxicity and micro-array analyses were performed to better understand the mechanism of action and revealed the importance of the drug as a metal ion chelator. Together, our findings suggest that disulfiram has the potential to be repurposed as an effective antibiotic to treat superficial human skin infections.

XS004 Dasatinib (XS004) Improves Variability and Bioavailability in Humans Using Amorphous Solid Dispersion Formulation of Dasatinib with Potential Implications for Its Clinical Use

Tyrosine kinase inhibitors (TKIs) have significantly improved the prognosis of patients with chronic myeloid leukemia (CML). Dasatinib, one of the most utilized TKIs, is formulated as a crystalline dasatinib monohydrate. This results in a low and pH-dependent solubility with highly variable intestinal absorption and plasma pharmacokinetics (PK). Poor dissolution of an anti-cancer drug is generally expected to result in low and highly variable bioavailability and plasma exposure, consequently jeopardizing an optimal and anticipated therapeutic response. Applying bioavailability enhancement techniques, such as amorphous solid dispersion (ASD) formulations, will reduce variability in plasma PK as solubility and intestinal absorption improves, and most importantly increase patient compliance, safety, and efficacy. XS004 dasatinib (XS004) (Xspray Pharma, Solna, Sweden) is a novel immediate release and ASD formulation of dasatinib produced with the HyNap™ technique. XS004 is designed to provide an increased solubility of dasatinib in acidic to neutral pH conditions, mitigating gastric pH dependency and leading to reduced variability and increased absorption and bioavailability of dasatinib. Here we report the results of a clinical study comparing the PK of XS004 and the original dasatinib product (reference) (Sprycel®, Bristol-Myers Squibb Company, NJ, USA), and results of a comparative in vitro solubility study. Plasma PK parameters were compared following single doses of XS004 (100 mg dasatinib ASD) and the reference product (140 mg dasatinib non-ASD) in 107 healthy volunteers at fasting conditions in a randomized, single dose, laboratory-blinded, 2 treatments, 4 period, 2 sequence, full replicate crossover, bioavailability study. In the in vitro study, dasatinib ASD and dasatinib monohydrate solubility was determined in the gastrointestinal (GI) relevance pH-interval of 1.2 to 8.0 at 37°C. The plasma exposure of XS004 (100 mg dasatinib ASD) was equivalent for all PK parameters with the reference product (140 mg dasatinib non-ASD) with least square geometric mean Cmax, AUC0-24h and AUC0-inf ratios of 100.8 (CI 90%, 90.8-112.0%), 94.2 (CI 90%, 87.5-101.4) and 92.2 (CI 90%, 86.2-98.6), respectively (Table 1). The intra-subject variability (coefficient of variation (CV%)) for AUC0-24 and AUC0-inf for the reference was approximately 3-fold and 2.5-fold higher than for XS004 (Table 2). For Cmax, the intra-subject variability was approximately 2-fold greater with the reference compared to XS004 (Table 2). The inter-individual variability was generally higher in all plasma PK parameters for the reference formulation (range: 38-128%) when compared to XS004 (range: 20-48%). There was considerably greater inter-subject variability (CV%) in Cmax, AUC0-24 and AUC0-inf after single dose administration of the reference product, when compared with XS004 (Table 2). The inter-individual variability was 4.5-fold, 4.3-fold and 4.8-fold greater for the reference product when compared to the test formulation for the three PK parameters. The in vitro solubility study provided higher apparent solubility of dasatinib ASD compared to the original crystalline dasatinib, explaining the improved in vivo GI absorption for the new preparation. Dasatinib ASD was unaffected and kept in solution over at least 2 hours in the pH range 1.2 to 5.0 and the solubility was at least 10-fold higher for dasatinib ASD compared to the dasatinib monohydrate at pH-values in the range 5.0 to 8.0. In conclusion, XS004 displayed a more robust and consistent GI-absorption and bioavailability, with significantly reduced intra- and inter-individual variability in plasma dasatinib concentrations, compared to the original non-ASD formulated dasatinib. The in vitro data showed that the solubility of dasatinib ASD was substantially less pH-dependent at GI-relevant pH values of 2.0 to 5.0. The results suggest that XS004, an ASD formulation of dasatinib, with improved biopharmaceutical features, reduces the risk of both low exposure and high exposure outliers, with lower risk of exposure outside the therapeutic window. This would likely diminish the risk of adverse events and optimize the therapeutic efficacy of dasatinib in patients with CML. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

A critical review of traditional and advanced characterisation tools to drive formulators towards the rational development of 3D printed oral dosage forms

The high degree of precision and control of 3D printing has given formulators the autonomy to engineer sophisticated and personalised medicines, starting a revolution in pharmaceutics. In addition, dosage forms with tailored drug release profile can be produced by changing some parameters of the 3D printing processes. Therefore, 3D printed medicines must be characterised in an orthogonal approach, to establish their physicochemical and biopharmaceutical features, and consequently to understand how these characteristics can be customised by changing the formulation and process parameters to ensure medicines’ safety and efficacy. Given the recent regulation and commercialisation of 3D printed medicines, several methods and techniques have been transposed from official compendia; however, formulators must still make a critical assessment of their practical implications. A comprehensive review of the findings obtained by the characterisation of 3D printed oral dosage forms using traditional and advanced techniques is therefore presented here, to drive formulators towards a rational pharmaceutical development pathway. The characterisation methods have been classified in terms of their physicochemical or biopharmaceutical character. Interestingly, beyond the rise of modern characterisation techniques, the reassessment of data obtained by traditional methods has provided knowledge and a solid foundation to support the evolution of 3D printing techniques in pharmaceutics.

Directional Self-Assembly of Ofloxacin and Syringic Acid: The First Salt Cocrystal of Ofloxacin with Phenolic Acid Displays Superior In Vitro/Vivo Biopharmaceutical Property and Enhanced Antibacterial Activity

A cocrystallization tactic of double optimization and synergistic enhancement efficacy has been proposed, aiming at maximizing the benefits of phenolic acid nutriment syringic acid (HSA) to perfect biopharmaceutical features of antibacterial drug ofloxacin (OA). This strategy utilizes the salt-forming function and cocrystallization ability of HSA interplaying with OA to assemble into a salt cocrystal, thus ameliorating OA’s physicochemical properties in vitro, which, in turn, can optimize its pharmacokinetic characteristics in vivo, making OA’s pharmaceutical peculiarities be doubly optimized on both in vivo and in vitro levels. Ulteriorly, the antibacterial potency of OA is heightened by stimulating the auxiliary antibacterial ability of HSA, fulfilling the cooperativeness of OA and HSA in antibacterial efficacy. Taking this tactic as orientation, the first OA– nutriment salt cocrystal, viz., [HOA+-SA–]-HSA-H2O, is directionally synthesized and structurally identified. Single-crystal X-ray diffraction substantiates that the salt cocrystal has a bilayer hole structure, wherein, a hexahelical hydrogen-bonding motif of [HOA+-SA–] salts situates outside with a double spiral of neutral HSA and H2O molecules inside, thus endowing the salt cocrystal with the capacity to simultaneously enhance solubility and permeability compared with OA itself, which achieves positive correlations with theoretical investigations. Intriguingly, the strengthened in vitro properties of the salt cocrystal have been effectually turned into in vivo pharmacokinetic advantages, displaying an advanced peak plasma concentration and protracted half-life along with raised relative bioavailability. More meaningfully, the antibacterial capacity of the salt cocrystal has also attained significant enhancement owing to the congenerous antibacterial action of OA and HSA. Therefore, this investigation not only offers a novice strategy for optimizing in vitro/vivo pharmaceutical characteristics and concurrently elevating antibacterial efficacy of OA through formation of the salt cocrystal but also fulfills a breakthrough in developing new salt cocrystal systems of antibacterial drugs.

Identification and antioxidant activity of natural functional microstructures produced with various neutral chemicals and bovine serum albumin

Stress-related conditions are a product of modern practices, and different treatments, such as meditation, yoga, and antistress medications, are utilized to reduce disincentive stress impact. Herbal medicines are rescued humanity from a variety of illnesses, and they could be able to provide adequate responses to stress-induced disturbances. In this article, bovine serum albumin (BSA) microparticles comprising germinated seeds wheat-ginger, germinated seeds wheat-rosemary loaded BSA microparticles (GSW-ROS-MPs), germinated seeds wheat-asafoetida loaded BSA microparticles (GSW-ASA-MPs), ginger-rosemary loaded BSA microparticles (GIN-ROS-MPs), resveratrol-ginger microspheres (RES-GIN-MSs), resveratrol-rosemary microspheres (RES-ROS-MSs), resveratrol-asafoetida microspheres (RES-ASA-MSs), and asafoetida-ginger microspheres (ASA-GIN-MSs) were enhanced to improve the biopharmaceutical features of the neutral compounds. While all MPs kinds synthesized had a so-called spherical morphology, the microspheres were found to be non-porous and with a smooth spherical surface morphology. The antiradical activities were tested .Antioxidant activities of RES-ASA-MSs and GIN-ROS-MPs were found to be higher. Therefore, BSA-containing RES-ASA-MSs and GIN-ROS-MPs can be alternative systems for improving the features of these compounds and administering them therapeutically effectively. In conclusion, all prepared compounds in the present study displayed substantial in vitro free radical-scavenging capability which was dose dependent and be applicate in oxidative stress-based diseases.

ИЗУЧЕНИЕ ТЕХНОЛОГИЧЕСКИХ ХАРАКТЕРИСТИК СУБСТАНЦИИ VMA-10-13 И ТЕХНОЛОГИЯ ИЗГОТОВЛЕНИЯ ТАБЛЕТОК

Abstract. Currently, intensive research is being conducted in the study of new biologically active substances for medical use that will be effective and safe for human use. Before the production of a medicinal product, the technological parameters and characteristics of a pharmaceutical substance must be carefully studied and scientifically substantiated. When creating and modernizing the technology of dosage forms, one of the most important stages is the assessment of bioavailability. It, in turn, depends on the physico-chemical properties of the active substance. The present work is devoted to the study of the technological properties of the original pharmaceutical substance of the quinazoline derivative, used as an active substance for the development of the composition and technology for obtaining a dosage form for oral use in the form of tablets using solid dispersion. The technological characteristics of a new biologically active compound –a derivative of quinazoline: 3-[2-(2-Methylphenylamino)-2-oxoethyl]-quinazoline-4(3H)–oh (laboratory code: VMA–10–13), capable of influencing pharmacological activity in the production of the dosage form, have been studied. The study examined key indicators: residual moisture, bulk density, flowability, ejection pressure, compressibility and disintegration of model tablets. The composition and technology of obtaining a solid dosage form (tablets) using a solid dispersion with improved biopharmaceutical characteristics have been developed. The main pharmaceutical and technological indicators of tablet quality are determined: average weight and disintegration. The data obtained allowed us to assume the content and course of further stages of pharmaceutical development.

Predicting Bile and Lipid Interaction for Drug Substances.

Predicting biopharmaceutical characteristics and food effects for drug substances may substantially leverage rational formulation outcomes. We established a bile and lipid interaction prediction model for new drug substances and further explored the model for the prediction of bile-related food effects. One hundred and forty-one drugs were categorized as bile and/or lipid interacting and noninteracting drugs using 1H nuclear magnetic resonance (NMR) spectroscopy. Quantitative structure-property relationship modeling with molecular descriptors was applied to predict a drug's interaction with bile and/or lipids. Bile interaction, for example, was indicated by two descriptors characterizing polarity and lipophilicity with a high balanced accuracy of 0.8. Furthermore, the predicted bile interaction correlated with a positive food effect. Reliable prediction of drug substance interaction with lipids required four molecular descriptors with a balanced accuracy of 0.7. These described a drug's shape, lipophilicity, aromaticity, and hydrogen bond acceptor capability. In conclusion, reliable models might be found through drug libraries characterized for bile interaction by NMR. Furthermore, there is potential for predicting bile-related positive food effects.

Hyaluronan-colistin conjugates: Synthesis, characterization, and prospects for medical applications

The development of nanotechnology-based antibiotic delivery systems (nanoantibiotics) is an important challenge in the effort to combat microbial multidrug resistance. These systems have improved biopharmaceutical characteristics by increasing local bioavailability and reducing systemic toxicity and the number and frequency of drug side effects. Conjugation of low -molecular -weight antibacterial agents with natural polysaccharides is an effective strategy for developing optimal targeted delivery systems with programmed release and reduced cytotoxicity. This study describes the synthesis of conjugates of colistin (CT) and hyaluronic acid (HA) using carbodiimide chemistry to conjugate the amino groups of CT with the carboxyl groups of HA. The obtained polysaccharide carriers had a degree of substitution (DS) with CT molecules of 3–10 %, and the CT content was 129–377 μg/mg. The size of the fabricated particles was 300–600 nm; in addition, there were conjugates in the form of single macromolecules (30–50 nm). The ζ-potential of developed systems was about −20 mV. In vitro release studies at pH 7.4 and pH 5.2 showed slow hydrolysis of amide bonds, with a CT release of 1–5 % after 24 h. The conjugates retained antimicrobial activity depending on the DS: at DS 8 %, the minimum inhibitory concentration (MIC) of the conjugate corresponded to the MIC of free CT. The resulting systems also reduced CT nephrotoxicity by 20–50 %. These new conjugates of CT with HA are promising for the development of nanodrugs for safe and effective antimicrobial therapy.

A novice cocrystal nanomicelle formulation of 5-fluorouracil with proline: The design, self-assembly and in vitro/vivo biopharmaceutical characteristics

To fully play the advantages of cocrystallization and nano-preparation techniques in regulating in vitro/vivo biopharmaceutical properties of anticancer drug 5-fluorouracil (FU), and further exploit new avenues in its formulation development, a recombination strategy of cocrystallization and nano-micellar self-assembly techniques is proposed. Thereinto, the cocrystallization technique is aiming at augmenting antitumor ability by ameliorating physicochemical performances of FU, while the nano-micellar self-assembly technique is mainly employed to achieve slowed release and long-term efficacy. Guided by this strategy, a new zwitterionic cocrystal of FU with L-proline (PL), FU-PL, is successfully synthesized, and then incorporated into carriers PEG-PCL to gain cocrystal micelles. The structure of FU-PL cocrystal and morphology of the cocrystal micelles are respectively characterized via various analytical means. The comparative studies of in vivo/vitro properties are systematacially conducted by theoretical and experimental methods. The results showcase that the cocrystal's solubility and permeability are 4.60 and 3.89 folds higher than those of pristine drug FU at pH 6.8, separately; and the drug loading and entrapment efficiency of the obtained cocrystal micelles with spherical particles of 146 nm are 2.39 and 1.74 times than those of FU micelles itself, respectively. Particularly, both the cocrystal and its micelles eventually bring about the excellent antitumor activity, but the cocrystal micelles improve even more significantly in comparison with the cocrystal. These in vitro advantages have promoted the in vivo absorption with increased relative bioavailability (FREL) of 2.72 relative to FU-PL cocrystal. More particularly, the cocrystal micelles have preferable sustained-release action relative to FU micelles, thus more efficaciously prolonging the half-life and therapy duration. All these findings not only supply a novice slow-release dosage form for FU with greater efficiency, but also fill the blank of the micelle researches for antitumor pharmaceutical cocrystals.

Preparation and Characterization of Fenofibrate Microparticles with Surface-Active Additives: Application of a Supercritical Fluid-Assisted Spray-Drying Process.

In this study, supercritical fluid-assisted spray-drying (SA-SD) was applied to achieve the micronization of fenofibrate particles possessing surface-active additives, such as d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS), sucrose mono palmitate (Sucroester 15), and polyoxyethylene 52 stearate (Myrj 52), to improve the pharmacokinetic and pharmacodynamic properties of fenofibrate. For comparison, the same formulation was prepared using a spray-drying (SD) process, and then both methods were compared. The SA-SD process resulted in a significantly smaller mean particle size (approximately 2 μm) compared to that of unprocessed fenofibrate (approximately 20 μm) and SD-processed particles (approximately 40 μm). There was no significant difference in the effect on the particle size reduction among the selected surface-active additives. The microcomposite particles prepared with surface-active additives using SA-SD exhibited remarkable enhancement in their dissolution rate due to the synergistic effect of comparably moderate wettability improvement and significant particle size reduction. In contrast, the SD samples with the surface-active additives exhibited a decrease in dissolution rate compared to that of the unprocessed fenofibrate due to the absence of particle size reduction, although wettability was greatly improved. The results of zeta potential and XPS analyses indicated that the surface-active additive coverage on the surface layer of the SD-processed particles with a better wettability was higher than that of the SA-SD-processed composite particles. Additionally, after rapid depletion of hydrophilic additives that were excessively distributed on the surfaces of SD-processed particles, the creation of a surface layer rich in poorly water-soluble fenofibrate resulted in a decrease in the dissolution rate. In contrast, the surface-active molecules were dispersed homogeneously throughout the particle matrix in the SA-SD-processed microparticles. Furthermore, improved pharmacokinetic and pharmacodynamic characteristics were observed for the SA-SD-processed fenofibrate microparticles compared to those for the SD-processed fenofibrate particles. Therefore, the SA-SD process incorporating surface-active additives can efficiently micronize poorly water-soluble drugs and optimize their physicochemical and biopharmaceutical characteristics.

Antiviral activity of the organic germanium complex with aciclovir against herpes simplex virus (Herpesviridae: Alphaherpesvirinae: Simplexvirus: Human alphaherpesvirus 1/2) in the in vitro and in vivo systems

A significant increase in the incidence of various forms of herpesvirus infection (HVI) determines the need to search for new approaches to the modification of one of the basic antiviral drugs aciclovir (ACV) and its dosage forms to improve their biopharmaceutical characteristics and increase the effectiveness of therapy. In this aspect, an innovative organic germanium complex with aciclovir (OGCA) is promising.The aim of the study was to assess the antiviral activity of OGCA against the herpes simplex virus (HSV) (human herpes virus, HHV) on the HVI models both in vitro and in vivo. We studied the activity of OGCA in a therapeutic regimen against HSV-1 (HHV-1) (Kl strain), HSV-2 (HHV-2) (VN strain) using virological and statistical research methods in the in vitro model of HVI on Vero cell culture and the model of genital herpes (GH) caused by HHV-2 (VN strain) in male guinea pigs (Canis porcellus). It was found OGCA inhibits the replication of HHV-1 and HHV-2 in Vero cells, and has anti-HHV activity in the GH model in male guinea pigs, leading to a decrease in the severity and duration of the disease, the intensity and duration of viral shedding. The most pronounced activity was detected when preparation was applied topically 5 times a day for 5 days at the early stages of infection (3% gel). The delayed use of OGCA (48 hours after infection) also had statistically significant efficacy compared to commercial reference drugs containing aciclovir or its pro-drugs: aciclovir (5% cream), AIL (acyclovir+interferon alfa-2b+lidocaine, 3% ointment), penciclovir (1% cream). OGCA significantly reduced the number of days of the pathogen shedding, as well as its infectivity, compared to animals in the control group and ones receiving placebo. The activity of OGCA, apparently, is due to its improved biopharmaceutical characteristics compared to aciclovir, as well as the presence of a number of biological activities of its constituent components. The results of the study allow us to consider OGCA as the basis for the development of antiviral agents for the treatment of HVI.

Chitosan-encapsulated niosomes for enhanced oral delivery of atorvastatin

Atorvastatin is the most commonly used hypolipidemic drug. It provides excellent protection against cardiovascular disease especially in subjects having high risk factors. However, atorvastatin has problematic biopharmaceutical characteristics due to low dissolution rate and extensive pre-systemic disposition. This contributed to reduced oral bioavailability and necessitated prescription of higher doses with subsequent unwanted side effects. The aim of this work is to probe chitosan-encapsulated niosomes for enhanced oral delivery of atorvastatin. Standard niosomes comprising Span 60, cholesterol and dicetyl-phosphate were prepared. Chitosan-encapsulated vesicles were prepared by coating the standard niosomes with chitosan followed by crosslinking with tripolyphosphate. Niosomes were characterized with respect to their morphology, size, atorvastatin entrapment and release. The antihyperlipidemic effect of atorvastatin-loaded niosomes was assessed after oral administration to hyperlipidemic mice. Both chitosan-encapsulated and unencapsulated vesicles were spherical. Chitosan-encapsulated niosomes had significantly lower particle size (96.9 nm) compared with unencapsulated niosomes (143.2 nm). The entrapment efficiency values were 57% and 55.5% for chitosan-encapsulated and unencapsulated niosomes, respectively with both formulations showing similar release pattern. Biochemical and histopathological evaluations of the therapeutic efficacy of different atorvastatin formulations in an in vivo model of hyperlipidemia revealed that the antihyperlipidemic effect could be ranked as follows: chitosan-encapsulated niosomes > unencapsulated niosomes > drug suspension. The study introduced chitosan-encapsulated niosomes as promising carrier for oral delivery of atorvastatin.

Clinical investigation of the biopharmaceutical characteristics of nifurtimox tablets – Implications for quality control and application

Nifurtimox is approved in Chagas disease and has been used in endemic countries since the 1960s. Nifurtimox, available as a 120 mg tablet, is administered with food typically three times daily, and dose is adjusted for age and bodyweight. Accurately or reproducibly fragmenting the 120 mg tablet for dose adjustment in young children and those with low bodyweight is problematic. Based on the existing tablet formulation, new nifurtimox 30 mg and 120 mg tablets have been developed in a format that can be divided accurately into 15 mg and 60 mg fragments. In adults with chronic Chagas disease, we investigated whether nifurtimox bioavailability is affected by tablet dissolution rate, and whether different diets affect nifurtimox bioavailability. In an open-label, three-period cross-over study (n=36; ClinicalTrials.gov, NCT03350295), patients randomly received three 30 mg tablet formulations (slow, medium, or fast dissolution; a 4 × 30 mg dose of one formulation per period). In an open-label, four-period cross-over study (n=24; ClinicalTrials.gov, NCT03334838) patients randomly fasted or received one of three meal types (high-fat/high-calorie, low-fat, dairy-based) before ingesting nifurtimox (a 4 × 30 mg dose per period). Acceptance criteria for no difference between groups were 90% confidence intervals (CIs) of exposure ratios in the range 0.8–1.25. Nifurtimox bioavailability was unaffected by tablet dissolution kinetics. Ratios of area under the curve at final assessment (AUC(0–tlast) [90% CI]) were: fast/medium dissolution, 1.061 (0.990–1.137); slow/medium dissolution, 0.964 (0.900–1.033); fast/slow dissolution, 1.100 (1.027–1.179). Compared with a fasting state, nifurtimox bioavailability increased by 73% after a high-fat/high-calorie meal (AUC(0–tlast) ratio [90% CI], 1.732 [1.581–1.898]); smaller increases were seen with the other meal types (low-fat: 1.602 [1.462–1.755]; dairy-based: 1.340 [1.222–1.468]). Although type of diet can affect bioavailability, taking nifurtimox with food is most important.

Topical Nanoemulgel for the Treatment of Skin Cancer: Proof-of-Technology.

The present study is a mechanistic validation of ‘proof-of-technology’ for the effective topical delivery of chrysin nanoemulgel for localized, efficient treatment of melanoma-affected skin. Background: Currently available treatments for skin cancer are inefficient due to systemic side effects and poor transcutaneous permeation, thereby presenting a formidable challenge for the development of novel nanocarriers. Methods: We opted for a novel approach and formulated a nanocomplex system composed of hydrophobic chrysin dissolved in a lipid mix, which was further nanoemulsified in Pluronic® F-127 gel to enhance physicochemical and biopharmaceutic characteristics. Chrysin, a flavone extracted from passion flowers, exhibits potential anti-cancer activities; however, it has limited applicability due to its poor solubility. Pseudo-ternary phase diagrams were constructed to identify the best self-nanoemulsifying region by varying the compositions of oil, Caproyl® 90 surfactant, Tween® 80, and co-solvent Transcutol® HP. Chrysin-loaded nanoemulsifying compositions were characterized for various physicochemical properties. Results: This thermodynamically stable, self-emulsifying drug delivery system showed a mean droplet size of 156.9 nm, polydispersity index of 0.26, and viscosity of 9100 cps after dispersion in gel. Mechanical characterization using Texture Analyzer exhibited that the gel had a hardness of 487 g and adhesiveness of 500 g. Ex vivo permeation through rat abdominal skin revealed significant improvement in percutaneous absorption measured as flux, the apparent permeability coefficient, the steady-state diffusion coefficient, and drug deposition. In vitro cytotoxicity on A375 and SK-MEL-2 cell lines showed a significantly improved therapeutic effect, thus ensuring reduction in dose. The safety of the product was established through biocompatibility testing on the L929 cell line. Conclusion: Aqueous, gel-based, topical, nanoemulsified chrysin is a promising technology approach for effective localized transcutaneous delivery that will help reduce the frequency and overall dose usage and ultimately improve the therapeutic index.

Obtaining Cocrystals by Reaction Crystallization Method: Pharmaceutical Applications.

Cocrystals have gained attention in the pharmaceutical industry due to their ability to improve solubility, stability, in vitro dissolution rate, and bioavailability of poorly soluble drugs. Conceptually, cocrystals are multicomponent solids that contain two or more neutral molecules in stoichiometric amounts within the same crystal lattice. There are several techniques for obtaining cocrystals described in the literature; however, the focus of this article is the Reaction Crystallization Method (RCM). This method is based on the generation of a supersaturated solution with respect to the cocrystal, while this same solution is saturated or unsaturated with respect to the components of the cocrystal individually. The advantages of the RCM compared with other cocrystallization techniques include the ability to form cocrystals without crystallization of individual components, applicability to the development of in situ techniques for the screening of high quality cocrystals, possibility of large-scale production, and lower cost in both time and materials. An increasing number of scientific studies have demonstrated the use of RCM to synthesize cocrystals, mainly for drugs belonging to class II of the Biopharmaceutics Classification System. The promising results obtained by RCM have demonstrated the applicability of the method for obtaining pharmaceutical cocrystals that improve the biopharmaceutical characteristics of drugs.