Preparation and Characterization of Pazopanib Hydrochloride-Loaded Four-Component Self-Nanoemulsifying Drug Delivery Systems Preconcentrate for Enhanced Solubility and Dissolution

Comparison of Solid Self-Nanoemulsifying Systems and Surface-Coated Microspheres: Improving Oral Bioavailability of Niclosamide

Purpose

This study aimed to develop a solid self-nanoemulsifying drug delivery system (SNEDDS) and surface-coated microspheres to improve the oral bioavailability of niclosamide.

Methods

A solubility screening study showed that liquid SNEDDS, prepared using an optimized volume ratio of corn oil, Cremophor RH40, and Tween 80 (20:24:56), formed nanoemulsions with the smallest droplet size. Niclosamide was incorporated into this liquid SNEDDS and spray-dried with calcium silicate to produce solid SNEDDS. Surface-coated microspheres were prepared using sodium alginate and poloxamer 407 and optimized through solubility and dissolution tests. Scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction were used to evaluate the physicochemical properties of the prepared solid SNEDDS, surface-coated microspheres, and the drug alone. The solubility, dissolution, and oral bioavailability were also assessed.

Results

Physicochemical evaluation demonstrated that niclosamide was converted to an amorphous state in the Solid SNEDDS formulation, with enhanced solubility and oral bioavailability. In comparison to niclosamide alone, solid SNEDDS exhibited an increase in drug solubility (approximately 2500-fold vs 158-fold) and oral bioavailability (approximately 10-fold vs 1.65-fold), significantly outperforming surface-coated microspheres.

Conclusion

This solid SNEDDS formulation may be an excellent candidate for niclosamide with improved oral bioavailability for repurposing.

Supersaturated Liquid Formulation of Pazopanib Hydrochloride Loaded with Synergistic Precipitation Inhibitors

This study aimed to develop a supersaturated liquid formulation (SSLF) to enhance the solubility and dissolution of pazopanib hydrochloride (PZH). SSLFs were prepared by a simple stirring method in a heated silicon oil bath (70 °C). PZH showed highly pH-dependent solubility (pH 1.2 > water >> pH 4.0 and pH 6.8) at 37 °C. The SSLF containing glycerol and polyvinylpyrrolidone K30 (PVP K30) increased PZH dispersion solubility (273.66 ± 48.91 μg/mL) at pH 6.8 by more than 50-fold compared with that of glycerol alone (<5 μg/mL), and the PZH precipitate particle size was considerably small (<100 nm). Moreover, the dispersion solubility of PZH from SSLF containing additional propylene glycol (PG) increased to 364.41 ± 2.47 μg/mL. The optimized SSLF10 (PZH/glycerol/PG/PVP K30 = 10/50/20/20, w/w) exhibited a high dissolution rate at pH 4.0 (>90%) and 6.8 (>55%) until 360 min, whereas PZH powder and PZH glycerol solution showed pH-dependent, low dissolution rates (<10%) under similar conditions. The supersaturation ratio of SSLF10 was very high at 29.88 and 18.36 at pH 6.8 and 4.0, respectively, indicating a stable PZH supersaturation solution. In the transmission electron microscopy analysis, PVP K30 and PG in SSLF10 synergistically suppressed PZH precipitation and recrystallization with small amorphous particles (<200 nm). Therefore, SSLF10 would be a promising formulation with enhanced solubility and dissolution rates regardless of medium pH.

Self-microemulsifying drug delivery system-based gastroretentive in situ raft of pazopanib with enhanced solubility and bioavailability

Pazopanib hydrochloride (PZH) is a Biopharmaceutics Classification System class II drug that faces challenges at the formulation forefront including low aqueous solubility (0.043 mg/mL) and poor oral bioavailability (14-39%). The present investigation aimed to develop a self-microemulsifying drug delivery system (SMEDDS) of PZH using a blend of Capryol® 90, Labrasol®, and propylene glycol to improve its solubility. Furthermore, a sustained-release SMEDDS-based gastroretentive floating system was developed and optimized using the Central Composite Design approach of DoE. The optimized SMEDDS-based in situ gelling raft, R-SM-PZH, exhibited minimal floating lag time (3.09 ± 0.8 s), optimal viscosity (1229.4 ± 20.9 cP) and density (0.327 ± 0.15 g/mL) as compared to other formulations under study. Additionally, R-SM-PZH was evaluated for its in vitro dissolution in FaSSGF and FeSSGF, pharmacokinetic profile, and MTT assay (against NCI-H460 lung cancer cells) compared to pure PZH. A 12 h sustained release, three-fold augmentation in dissolution rate and bioavailability, and 15-fold enhancement in cytotoxicity were observed in comparison to pure PZH. Thus, the SMEDDS-based in situ gelling raft presents a promising approach to advancing the developability potential of PZH.

QbD-Based Development and Evaluation of Pazopanib Hydrochloride Extrudates Prepared by Hot-Melt Extrusion Technique: In Vitro and In Vivo Evaluation

BACKGROUND

Pazopanib hydrochloride (PZB) is a protein kinase inhibitor approved by the United States Food and Drug Administration and European agencies for the treatment of renal cell carcinoma and other renal malignancies. However, it exhibits poor aqueous solubility and inconsistent oral drug absorption. In this regard, the current research work entails the development and evaluation of the extrudates of pazopanib hydrochloride by the hot-melt extrusion (HME) technique for solubility enhancement and augmenting oral bioavailability.

RESULTS

Solid dispersion of the drug was prepared using polymers such as Kollidon VA64, hydroxypropylmethylcellulose (HPMC), Eudragit EPO, and Affinisol 15LV in a 1:2 ratio by the HME process through a lab-scale 18 mm extruder. Systematic optimization of the formulation variables was carried out with the help of custom screening design (JMP Software by SAS, Version 14.0) to study the impact of polymer type and plasticizer level on the quality of extrudate processability by measuring the torque value, appearance, and disintegration time as the responses. The polymer blends containing Kollidon VA64 and Affinisol 15LV resulted in respective clear transparent extrudates, while Eudragit EPO and HPMC extrudates were found to be opaque white and brownish, respectively. Furthermore, evaluation of the impact of process parameters such as screw rpm and barrel temperature was measured using a definitive screening design on the extrude appearance, torque, disintegration time, and dissolution profile. Based on the statistical outcomes, it can be concluded that barrel temperature has a significant impact on torque, disintegration time, and dissolution at 30 min, while screw speed has an insignificant impact on the response variables. Affinisol extrudates showed less moisture uptake and faster dissolution in comparison to Kollidon VA64 extrudates. Affinisol extrudates were evaluated for polymorphic stability up to a 3-month accelerated condition and found no recrystallization. PZB-Extrudates using the Affinisol polymer (Test formulation A) revealed significantly higher bioavailability (AUC) in comparison to the free Pazopanib drug and marketed formulation.

Solubility enhancement of fexofenadine using self-nano emulsifying drug delivery system for improved biomimetic attributes

BACKGROUND

Fexofenadine is a poorly water-soluble drug, which limit its bioavailability and ultimately therapeutic efficacy. Liquid self-nano emulsifying drug delivery system (L-SNEDDs) is an approach that can enhance the solubility of fexofenadine by increasing its surface area and reducing the particle size, which increases the rate and extent of drug dissolution.

METHOD

In this investigation, L-SNEDDs of fexofenadine was made up using surfactants and co-surfactant. The SNEDDS formulation was optimized using a pseudo-ternary phase diagram and characterized.

RESULTS

The optimized L-SNEDDS incorporated fexofenadine were thermodynamically stable and showed mean droplet size and zeta potential of 155nm and -18mV, respectively unaffected by the media pH. In addition, the viscosity, and refractive index were observed 18.4 and 1.49 cps, respectively for optimized L-SNEDDS fortified fexofenadine. The results of Fourier transform infrared spectroscopy revealed an insignificant interaction between the fexofenadine and excipients. A drug loading efficiency of 94.20% resulted with a complete in vitro drug release in 2h, compared with the pure drug, which demonstrate significant improvement in the efficacy. Moreover, these results signify that on further in vivo assessment L-SNEDDS fortified fexofenadine can indicate improvement in pharmacokinetic and clinical outcome.

CONCLUSION

Thus, the investigation revealed that, the L-SNEDDs incorporated fexofenadine was most effective with a mixture of surfactant and co-surfactant with improved solubility intend to relieve pain associated with inflammation with single-dose oral administration.

Drug-like properties of tyrosine kinase inhibitors in ophthalmology: Formulation and topical availability

Tyrosine kinase inhibitors (TKIs) can inhibit edema and neovascularization, such as in age-related macular degeneration and diabetic retinopathy. However, their topical administration in ophthalmology is limited by their toxicity and poor aqueous solubility. There are multiple types of TKIs, and each TKI has an affinity to more than one type of receptor. Studies have shown that ocular toxicity can be addressed by selecting TKIs that have a high affinity for specific vascular endothelial growth factor receptors (VEGFRs) but a low affinity for epidermal growth factor receptors (EGFRs). Drugs permeate from the aqueous tear fluid into the eye via passive diffusion. Thus, a sustained high concentration of the dissolved drug in the aqueous tear fluid is essential for a successful delivery to posterior tissues such as the retina. Unfortunately, the aqueous solubility of the TKIs that have the most favorable VEGFR/EGFR affinity ratio, that is, axitinib and cabozantinib, is well below 1 µg/mL, making their topical delivery very challenging. This is a review of the drug-like properties of TKIs that are currently being evaluated or have been evaluated as ophthalmic drugs. These properties include their solubilization, cyclodextrin complexation, and ability to permeate from the aqueous tear fluid to the posterior eye segment.

The Impact of Polymers on Enzalutamide Solid Self-Nanoemulsifying Drug Delivery System and Improved Bioavailability

Enzalutamide (ENZ), marketed under the brand name Xtandi® as a soft capsule, is an androgen receptor signaling inhibitor drug actively used in clinical settings for treating prostate cancer. However, ENZ's low solubility and bioavailability significantly hinder the achievement of optimal therapeutic outcomes. In previous studies, a liquid self-nanoemulsifying drug delivery system (L-SNEDDS) containing ENZ was developed among various solubilization technologies. However, powder formulations that included colloidal silica rapidly formed crystal nuclei in aqueous solutions, leading to a significant decrease in dissolution. Consequently, this study evaluated the efficacy of adding a polymer as a recrystallization inhibitor to a solid SNEDDS (S-SNEDDS) to maintain the drug in a stable, amorphous state in aqueous environments. Polymers were selected based on solubility tests, and the S-SNEDDS formulation was successfully produced via spray drying. The optimized S-SNEDDS formulation demonstrated through X-ray diffraction and differential scanning calorimetry data that it significantly reduced drug crystallinity and enhanced its dissolution rate in simulated gastric and intestinal fluid conditions. In an in vivo study, the bioavailability of orally administered formulations was increased compared to the free drug. Our results highlight the effectiveness of solid-SNEDDS formulations in enhancing the bioavailability of ENZ and outline the potential translational directions for oral drug development.

Enhanced Stability and Improved Oral Absorption of Enzalutamide with Self-Nanoemulsifying Drug Delivery System

The purpose of this study is to develop and evaluate a self-nanoemulsifying drug delivery system (SNEDDS) to improve the oral absorption of poorly water-soluble enzalutamide (ENZ). Considering the rapid recrystallization of the drug, based on solubility and crystallization tests in various oils, surfactants and co-surfactants, Labrafac PG 10%, Solutol HS15 80%, and Transcutol P 10%, which showed the most stable particle size and polydispersity index (PDI) without drug precipitation, were selected as the optimal SNEDDS formulation. The optimized SNEDDS formulation showed excellent dissolution profiles for all the drugs released at 10 min of dissolution due to the increased surface area with a small particle size of approximately 16 nm. Additionally, it was confirmed to be stable without significant differences in physical and chemical properties for 6 months under accelerated conditions (40 ± 2 °C, 75 ± 5% RH) and stressed conditions (60 ± 2 °C). Associated with the high dissolutions of ENZ, pharmacokinetic parameters were also greatly improved. Specifically, the AUC was 1.9 times higher and the Cmax was 1.8 times higher than those of commercial products (Xtandi® soft capsule), resulting in improved oral absorption. Taken together with the results mentioned above, the SNEDDS could be an effective tool as a formulation for ENZ and other similar drugs.

Paliperidone–Cation Exchange Resin Complexes of Different Particle Sizes for Controlled Release

This study aimed to develop electrolyte complexes of paliperidone (PPD) with various particle sizes using cation-exchange resins (CERs) to enable controlled release (both immediate and sustained release). CERs of specific particle size ranges were obtained by sieving commercial products. PPD–CER complexes (PCCs) were prepared in an acidic solution of pH 1.2 and demonstrated a high binding efficiency (>99.0%). PCCs were prepared with CERs of various particle sizes (on average, 100, 150, and 400 μm) at the weight ratio of PPD to CER (1:2 and 1:4). Physicochemical characterization studies such as Fourier-transform infrared spectroscopy, differential scanning calorimetry, powder X-ray diffraction, and scanning electron microscopy between PCCs (1:4) and physical mixtures confirmed PCC formation. In the drug release test, PPD alone experienced a complete drug release from PCC of >85% within 60 min and 120 min in pH 1.2 and pH 6.8 buffer solutions, respectively. Alternatively, PCC (1:4) prepared with CER (150 μm) formed spherical particles and showed an almost negligible release of PPD in pH 1.2 buffer (<10%, 2 h) while controlling the release in pH 6.8 buffer (>75%, 24 h). The release rate of PPD from PCCs was reduced with the increase in CER particle size and CER ratio. The PCCs explored in this study could be a promising technology for controlling the release of PPD in a variety of methods.

Assessing the Solubility of Baricitinib and Drug Uptake in Different Tissues Using Absorption and Fluorescence Spectroscopies

The low water solubility of baricitinib (BCT) limits the development of new formulations for the topical delivery of the drug. The aims of this study were to assess the solubility of BCT in different solvents, including Transcutol, a biocompatible permeation enhancer that is miscible in water, to evaluate the drug uptake in human skin and porcine tissues (sclera, cornea, oral, sublingual, and vaginal), and to subsequently extract the drug from the tissues so as to determine the drug recovery using in vitro techniques. Analytical methods were developed and validated for the quantification of BCT in Transcutol using absorption and fluorescence spectroscopies, which are complementary to each other and permit the detection of the drug across a broad range of concentrations. Results show that Transcutol permits an increased drug solubility, and that BCT is able to penetrate the tissues studied. The solutions of BCT in Transcutol were stable for at least one week. Hence, Transcutol may be a suitable solvent for further development of topical formulations.

Amidated Pluronic Decorated Muco-Penetrating Self-Nano Emulsifying Drug Delivery System (SNEDDS) for Improved Anti-Salmonella typhi Potential

The enteric system residing notorious Salmonella typhimurium (S. typhi) is an intracellular, food-borne, and zoonotic pathogen causing typhoid fever. Typhoid fever is one of the leading causes of mortality and morbidity in developing and underdeveloped countries. It also increased the prevalence of multidrug resistance globally. Currently, available anti-bacterial modalities are unable to penetrate into the intracellular compartments effectively for eradicating S. typhi infection. Therefore, in this study, we developed nanostructured lipid-based carriers in the form of a self-nanoemulsifying drug delivery system (SNEDDS) for targeted delivery of ciprofloxacin (CIP) into the S. typhi intracellular reservoirs. Capryol 90, Tween 80, and Span 20 were finalized as suitable oil, surfactant, and co-surfactant, respectively, according to the pseudoternary phase diagram emulsifying region. Targeting capability and mucopenetration of the SNEDDS was attributed to the inclusion of amidated pluronic (NH2-F127). Developed NH2-F127 SNEDDS were characterized via physicochemical, in vitro, ex vivo, and in vivo evaluation parameters. The size of the SNEDDS was found to be 250 nm, having positively charged zeta potential. In vitro dissolution of SNEDDS showed 80% sustained release of CIP in 72 h with maximum entrapment efficiency up to 90% as well as good hemocompatibility by showing less than 0.2% hemolysis and 90% biocompatibility. The survival rate of S. typhi in macrophages (RAW 264.7) was minimal, i.e., only 2% in the case of NH2-F127 SNEDDS. Macrophage uptake assay via nanostructures confirmed the maximum cellular uptake as evidenced by the highest fluorescence. Biofilm dispersion assay showed rapid eradication of developed resistant biofilms on the gall bladder. In vivo pharmacokinetics showed improved bioavailability by showing an increased area under the curve (AUC) value. Taken together, NH2-F127-SNEDDS can be utilized as an alternative and efficient delivery system for the sustained release of therapeutic amounts of CIP for the treatment of S. typhi.