Investigation of Patient-Centric 3D-Printed Orodispersible Films Containing Amorphous Aripiprazole.

The objective of this study was to design and evaluate an orodispersible film (ODF) composed of aripiprazole (ARP), prepared using a conventional solvent casting technique, and to fuse a three-dimensional (3D) printing technique with a hot-melt extrusion (HME) filament. Klucel® LF (hydroxypropyl cellulose, HPC) and PE-05JPS® (polyvinyl alcohol, PVA) were used as backbone polymers for 3D printing and solvent casting. HPC-, PVA-, and ARP-loaded filaments were applied for 3D printing using HME. The physicochemical and mechanical properties of the 3D printing filaments and films were optimized based on the composition of the polymers and the processing parameters. The crystalline states of drug and drug-loaded formulations were investigated using differential scanning calorimetry (DSC) and powder X-ray diffraction (XRD). The dissolution and disintegration of the 3D-printed films were faster than those of solvent-cast films. HPC-3D printed film was fully disintegrated within 45 ± 3.5 s. The dissolution rate of HPC films reached 80% within 30 min at pH 1.2 and pH 4.0 USP buffer. There was a difference in the dissolution rate of about 5 to 10% compared to PVA films at the same sampling time. The root mean square of the roughness (Rq) values of each sample were evaluated using atomic force microscopy. The higher the Rq value, the rougher the surface, and the larger the surface area, the more salivary fluid penetrated the film, resulting in faster drug release and disintegration. Specifically, The HPC 3D-printed film showed the highest Rq value (102.868 nm) and average surface roughness (85.007 nm). The puncture strength of 3D-printed films had desirable strength with HPC (0.65 ± 0.27 N/mm2) and PVA (0.93 ± 0.15 N/mm2) to prevent deformation compared to those of marketed film products (over 0.34 N/mm2). In conclusion, combining polymer selection and 3D printing technology could innovatively design ODFs composed of ARP to solve the unmet medical needs of psychiatric patients.

Improved Bioavailability of Poorly Water-Soluble Drug by Targeting Increased Absorption through Solubility Enhancement and Precipitation Inhibition.

Itraconazole (ITZ) is a class II drug according to the biopharmaceutical classification system. Its solubility is pH 3-dependent, and it is poorly water-soluble. Its pKa is 3.7, which makes it a weak base drug. The aim of this study was to prepare solid dispersion (SD) pellets to enhance the release of ITZ into the gastrointestinal environment using hot-melt extrusion (HME) technology and a pelletizer. The pellets were then filled into capsules and evaluated in vitro and in vivo. The ITZ changed from a crystalline state to an amorphous state during the HME process, as determined using DSC and PXRD. In addition, its release into the gastrointestinal tract was enhanced, as was the level of ITZ recrystallization, which was lower than the marketed drug (Sporanox®), as assessed using an in vitro method. In the in vivo study that was carried out in rats, the AUC0-48h of the commercial formulation, Sporanox®, was 1073.9 ± 314.7 ng·h·mL-1, and the bioavailability of the SD pellet (2969.7 ± 720.6 ng·h·mL-1) was three-fold higher than that of Sporanox® (*** p < 0.001). The results of the in vivo test in beagle dogs revealed that the AUC0-24h of the SD-1 pellet (which was designed to enhance drug release into gastric fluids) was 3.37 ± 3.28 µg·h·mL-1 and that of the SD-2 pellet (which was designed to enhance drug release in intestinal fluids) was 7.50 ± 4.50 µg·h·mL-1. The AUC of the SD-2 pellet was 2.2 times higher than that of the SD-1 pellet. Based on pharmacokinetic data, ITZ would exist in a supersaturated state in the area of drug absorption. These results indicated that the absorption area is critical for improving the bioavailability of ITZ. Consequently, the bioavailability of ITZ could be improved by inhibiting precipitation in the absorption area.

Preparation of Hot-Melt Extruded Dosage Form for Enhancing Drugs Absorption Based on Computational Simulation.

The aim of this study was to control the dissolution rate and permeability of cilostazol. To enhance the dissolution rate of the active pharmaceutical ingredient (API), hot-melt extrusion (HME) technology was applied to prepare a solid dispersion (SD). To control permeability in the gastrointestinal tract regardless of food intake, the HME process was optimized based on physiologically based pharmacokinetic (PBPK) simulation. The extrudates were produced using a laboratory-scale twin-screw hot-melt extruder with co-rotatory screws and a constant feeding rate. Next, for PBPK simulation, parameter-sensitive analysis (PSA) was conducted to determine the optimization approach direction. As demonstrated by the dissolution test, the solubility of extrudate was enhanced comparing cilostazol alone. Based on the PSA analysis, the surfactant induction was a crucial factor in cilostazol absorption; thus, an extrudate with an even distribution of lipids was produced using hot-melt extrusion technology, for inducing the bile salts in the gastrointestinal tract. In vivo experiments with rats demonstrated that the optimized hot-melt extruded formulation was absorbed more rapidly with lower deviation and regardless of the meal consumed when compared to marketed cilostazol formulations.

Preparation of celecoxib tablet by hot melt extrusion technology and application of process analysis technology to discriminate solubilization effect.

The aim of this study was to prepare various types of solid dispersions (SDs) by the hot-melt extrusion technique. Next, process analytical technology (PAT) such as Fourier transform-infrared (FT-IR) and Raman and near infrared (NIR) spectroscopy were applied to determine the solubilization effect. The SDs and its tablets were prepared. Differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM) were performed to determine the morphological and crystalline characteristics of the SDs. Additionally, PAT analyses were performed to identify the solubilization of the celecoxib. Dissolution testing was performed using the paddle method indicated in the US Pharmacopeia Apparatus II. Based on SEM, DSC, and XRD analysis, all SDs changed successfully from the crystalline to the amorphous form. However, FT-IR, Raman, and NIR analysis used in PAT showed that SDs were divided into two groups. New peaks formed as the amount of drug loading increased to >50% in the SD and the dissolution rates were lower than those of the marketed drug. Drug loading levels of ≤50% showed no new peak and exhibited strong solubilization effects. PAT tools can be used to discriminate between extrudates with poor (<50% drug release after 120 min) and desirable (>75% drug release after 120 min) dissolution performance.

In Vitro-In Vivo Correlation Using In Silico Modeling of Physiological Properties, Metabolites, and Intestinal Metabolism.

BACKGROUND: Recently, pharmaceutical research has focused on in vitro-in vivo correlation as a novel challenge, and in silico modeling has been an important component. As in silico models are highly representative of practical use, regulatory agencies such as the US Food and Drug Administration and European Medicines Agency have recognized and utilized in silico modeling as a useful tool; this allows pharmaceutical organizations to use Physiologically Based Pharmacokinetic (PBPK) models for decision-making, which may aid the financial efficiency of a clinical trial. However, some studies have shown differences of up to approximately 40% in pharmacokinetic parameters such as area under the curve or maximum serum concentration between observed and simulated data. METHODS: Gastroplus™ was used to demonstrate current PBPK simulation. 46 research papers were compared with each other's applications of PBPK simulation. RESULTS: To improve the accuracy of simulation, additional factors may need to be considered, such as precise volume of gastrointestinal sections, specific metabolism of the target drug, and physicochemical data of drug metabolites. Furthermore, the results of these simulations would be extremely valuable to the relevant applications. Simulation programs using Advanced Compartmental Absorption and Transit (ACAT)/PBPK modeling could be a powerful tool for companies performing pre-clinical experiments, and could provide a solution for the ethical issues and economic constraints of clinical trials. CONCLUSION: If in silico modeling produced more precise results that could closely match clinical data, it could be more readily used to screen drug pharmacodynamics in bodily systems, and the efficiency of clinical trials would be improved. However, simulation programs are currently limited in their accuracy of pharmacodynamic predictions. In developing new drugs, pharmaceutical companies should address this issue in order to improve in silico/PBPK modeling in the future.

Process Analytical Quality Control of Tailored Drug Release Formulation Prepared via Hot-Melt Extrusion Technology.

The objective of the present study was to compare the influence of Eudragit® RS PO and RL PO blends on the release of water-soluble and insoluble drugs from hot-melt extruded formulations. In addition, we aimed to evaluate drug content uniformity and distribution by Fourier transform-infrared (FT-IR) chemical imaging. Theophylline (TP) and carbamazepine (CBZ) were selected as the water-soluble and insoluble model drugs, respectively. Eudragit® RS PO and RL PO were selected as the polymeric matrices. FT-IR chemical imaging clearly demonstrated the content uniformity and distribution for both drugs in the extrudates, which was confirmed by HPLC. Increasing the ratio of Eudragit® RL PO led to an increase in the in vitro drug release, whereas an increase in the ratio of Eudragit® RS PO sustained the drug release for up to 12 h. The hot-melt extrusion of TP and CBZ with varying ratios of Eudragit® RS PO and RL PO can be employed to tailor the drug release profiles. In this study, we demonstrated, for the first time, the use of FT-IR chemical imaging as a process analytical technique to determine the drug content uniformity and distribution. Our data correlated well with the results of HPLC analysis in the study of tailored drug release from the prepared hot-melt extruded formulation.

Modulation of microenvironmental pH and utilization of alkalizers in crystalline solid dispersion for enhanced solubility and stability of clarithromicin.

Clarithromycin (CAM) is known to be poorly water-soluble and acid-labile drug. Various alkalizers such as MgO, Na2CO3, Na2HPO4 and NaHCO3 were utilized to modulate the microenvironmental pH (pHM) and to improve the low stability and solubility of CAM in a crystalline-solid dispersion system (CSD). Polyvinylpyrrolidone (PVP K-30) and hydroxypropylmethylcellulose (HPMC) 4000-based CSDs containing alkalizers were prepared by cosolvent precipitation followed by evaporation process. The dried-CSDs mixed with microcrystalline cellulose, 2% croscarmellose sodium, and 1% magnesium stearate was then directly compressed into tablet. A dissolution test was carried out in 900 mL of pH 5.0 buffer solutions at 37 °C with a 50 rpm paddle speed. pHM, surface morphology, and structural behaviors were investigated. The dissolution rates of CAM in CSD containing alkalizers were improved. The drug in CSD remained crystalline as observed by differential scanning calorimetry and powder X-ray diffraction. Scanning electron microscopy revealed nearly identical images regardless of the sorts and amounts of carriers. PVP-based CSD tablet without alkalizer showed greater drug release, while HPMC-based CSD tablet without alkalizer retarded drug release due to its greater swelling capability. However, when the alkalizers were added in CSD tablet, the drug release was sharply increased. NaHCO3 induced the most rapid drug release while MgO retarded drug dissolution. Alkalizers in CSD also could maintain the pHM of the tablet above pH 5 under acidic conditions. The use of pH modifiers in CSDs could provide a useful method to improve the dissolution rate and stability of CAM via modulation of pHM without changing drug crystallinity.

New investigation of distribution imaging and content uniformity of very low dose drugs using hot-melt extrusion method.

The content uniformity of low dose drugs in dosage forms is very important for quality assurance. The aim of this study was to prepare uniformly and homogeneously distributed dosage forms of very low-dose drugs using twin screw hot-melt extrusion (HME) and to investigate the distribution of drugs using instrumental analyses. For the feasibility of HME method, a very low amount of coumarin-6, a fluorescent dye, was used to visualize distribution images using confocal laser scanning microscope (CLSM). Limaprost, tamsulosin and glimepiride were then used as low-dose model drugs to study the applicability of HME for content uniformity and distribution behaviors. Hydrophilic thermosensitive polymers with low melting point, such as Poloxamer188 and polyethylene glycol (PEG) 6000, were chosen as carriers. The melt extrusion was carried out around 50°C, at which both carriers were easily dissolved but model drugs remained in solid form. The physicochemical properties of the hot-melt extrudates, including differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and Fourier transform infrared spectroscopy (FT-IR), were measured. Content uniformity of the drugs was also checked by HPLC. CLSM imaging showed that model drugs were well distributed throughout the hot-melt extrudate, giving better content uniformity with low batch-to-batch variations compared with simple physical mixtures. DSC, PXRD and FT-IR data showed that there was no interaction or interference between model drugs and thermosensitive polymers. The current HME methods could be used to prepare uniformly distributed and reproducible solid dosage forms containing very low dose drugs for further pharmaceutical applications.

Drug release-modulating mechanism of hydrophilic hydroxypropylmethylcellulose matrix tablets: distribution of atoms and carrier and texture analysis.

Although release profiles of drug from hydrophilic matrices have been well recognized, the visual distribution of hydroxypropylmethylcellulose (HPMC) and atoms inside of internal structures of hydrophilic HPMC matrices has not been characterized. In this paper, drug release mechanism from HPMC matrix tablet was investigated based on the release behaviors of HPMC, physical properties of gelled HPMC tablet and atomic distributions of formulation components using diverse instruments. A matrix tablet consisting of hydroxypropyl methylcellulose (HPMC 6, 4,000 and 100,000 mPa·s), chlorpheniramine maleate (CPM) as a model and fumed silicon dioxide (Aerosil(®) 200) was prepared via direct compression. The distribution of atoms and HPMC imaging were characterized using scanning electron microscope (SEM)/ energy-dispersive X-ray spectroscopy (EDX), and near-infrared (NIR) analysis, respectively as a function of time. A texture analyzer was also used to characterize the thickness and maintenance of gel layer of HPMC matrix tablet. The HPMC matrix tablets showed Higuchi release kinetics with no lag time against the square root of time. High viscosity grades of HPMC gave retarded release rate because of the greater swelling and gel thickness as characterized by texture analyzer. According to the NIR imaging, low-viscosity-grade HPMC (6 mPa·s) quickly leached out onto the surface of the tablet, while the high-viscosity-grade HPMC (4000 mPa·s) formed much thicker gel layer around the tablet and maintained longer via slow erosion, resulting in retarded drug release. The atomic distribution of the drug (chlorine, carbon, oxygen), HPMC (carbon, oxygen) and silicon dioxide (silica, oxygen) and NIR imaging of HPMC corresponded with the dissolution behaviors of drug as a function of time. The use of imaging and texture analyses could be applicable to explain the release- modulating mechanism of hydrophilic HPMC matrix tablets.

Effects of chromosomal variations on pharmacokinetic activity of zolpidem in healthy volunteers: an array-based comparative genomic hybridization study.

Zolpidem has been known as a very safe and effective hypnotic drug used to treat a variety of patients with insomnia. Even though the same dose of the medicine is administered to each patient, the blood level of zolpidem and the time required to obtain peak concentration are not consistent among different people. We evaluated the relationship between the peak concentrations of zolpidem and chromosomal imbalances using a high-resolution genome-wide array-based comparative genomic hybridization (CGH) in 16 healthy volunteers in order to detect the genetic factors underlying the variations. The present study showed that chromosomal losses were detected in the 4q35.2, 9p13.1 and 9p12 regions, and those gains were indicated in the 2p14, 11q13.4 and 15q11.2 regions. The abnormal regions were confirmed by fluorescence in situ hybridization (FISH) and real-time PCR. It is suggested that array-CGH analysis may be used as a measure for pharmacogenomic applications in the patients with insomnia and for further exploration of candidate genomic regions implicated in sleep disturbances.

Safety assessment of potential lactic acid bacteria Bifidobacterium longum SPM1205 isolated from healthy Koreans.

The safety assessment of Bifidobacterium longum SPM1205 isolated from healthy Koreans and this strain's inhibitory effects on fecal harmful enzymes of intestinal microflora were investigated. The overall safety of this strain was investigated during a feeding trial. Groups of SD rats were orally administered a test strain or commercial reference strain B. longum 1 x 10(9) CFU/kg body weight/day for four weeks. Throughout this time, their feed intake, water intake and live body weight were monitored. Fecal samples were periodically collected to test harmful enzyme activities of intestinal microflora. At the end of the four-week observation period, samples of blood, liver, spleen, kidney, and gut tissues were collected to determine for hematological parameters and histological differences. The results obtained in this experiment demonstrated that four weeks of consumption of this Bifidobacterium strain had no adverse effects on rat's general health status, blood biochemical parameters or histology. Therefore, it is likely to be safe for human use. Fecal harmful enzymes such as beta-glucosidase, beta-glucuronidase, tryptophanase and urease, were effectively inhibited during the administration of the B. longum SPM1205. These results suggested that this B. longum SPM 1205 could be used for humans as a probiotic strain.

The protein polymorphism of haptoglobin in Korean elite athletes.

OBJECTIVE: To investigate protein polymorphism of the haptoglobin (Hp) and the relationship between Hp phenotypes and anthropometric or biochemical parameters in elite Korean male athletes. MATERIALS AND METHODS: Serum samples were collected from 120 Korean male elite athletes. The Hp phenotypes were determined by polyacrylamide gel electrophoresis, followed by peroxidase staining. Then anthropometric or biochemical measurements were made: body composition, blood pressures, ventilatory responses, cholesterol (total, LDL cholesterol and HDL cholesterol), triglyceride, apolipoprotein A1, lipoprotein (a), creatine phosphokinase and lactate dehydrogenase. RESULTS: The gene frequencies of the Hp1-1, Hp2-1 and Hp2-2 phenotypes in Korean male athletes were 12, 37 and 51%, respectively; this polymorphism was significantly associated with the VO(2max) index in the athletes. An excess of the Hp1 allele was also observed in marathon runners compared with the other sporting activities, although it did not have any statistical significance. CONCLUSION: Hp polymorphism exists in elite Korean male athletes and Hp phenotype may be a useful marker for endurance performance in these male athletes.