Study on Formulation, in vivo Exposure, and Passive Targeting of Intravenous Itraconazole Nanosuspensions

Challenges of nanoparticle albumin bound (nab™) technology: Comparative study of Abraxane® with a newly developed albumin-stabilized itraconazole nanosuspension

Nanoparticle albumin bound™ (nab™) technology is an established delivery platform for development of albumin stabilized nanoparticles as drug delivery systems for poorly water-soluble drugs. By using albumin for particle stabilization, nab™ technology does not require solubilizers or emulsifiers for the formulation of poorly water-soluble drugs for intravenous use. Despite the great potential, however, to date only two products based on nab™ technology have been approved by the Food and Drug Administration: Abraxane® (nab™ paclitaxel) and Fyarro® (nab™ rapamycin). In this study, the commercially available product Abraxane® was characterized in comparison to an albumin stabilized nanosuspension for the poorly water-soluble drug itraconazole. The aim of this study was to identify critical product parameters of the nanosuspensions depending on the manufacturing process in order to assess the transferability of nab™ technology to other drugs. The colloidal properties, stabilizing protein composition and particle disintegration behavior were analyzed. In addition, studies were carried out on the impact of the key process step, the high-pressure homogenization, using a design of experiments (DoE) approach. A nanosuspension comprising spherical, stable drug nanoparticles stabilized by a large fraction of dissolved albumin around the nanoparticles were identified. During the manufacturing process, the drug core was coated with a layer of albumin, which was cross-linked to a certain level. The Abraxane® and itraconazole suspensions differed in the analyzed protein fraction, with stronger cross-linking at the particle surface for Abraxane®. Both active pharmaceutical ingredients were present in the amorphous state as nanoparticles. In vitro disintegration studies performed to mimic a strong dilution during intravenous application showed the disintegration of the nanoparticles. All in all, the analysis underlined the transferability of the nab™ technology to selected other poorly water-soluble drugs with the great advantage of eliminating solubilizers and emulsifiers for intravenous applications.

Nanosuspensions technology as a master key for nature products drug delivery and In vivo fate

The drug nanosuspensions is a universal formulation approach for improved drug delivery of hydrophobic drugs and one the most promising approaches for increasing the biopharmaceutical performance of poorly water-soluble drug substances, especially for nature products. This review aimed to summarize the nanosuspensions preparation approaches and the main technological difficulties encountered in nanosuspensions development, such as guidelines for stabilizers screening, in vivo fate of the intravenously administrated nanosuspensions, and how to realize the intravenously target delivery was reviewed. Furthermore, challenges of nanosuspensions for the nature products delivery also was discussed and commented. Therefore, it hoped to provide reference and assistance for the nanosuspensions production, stabilizers usage, and predictability of in vivo fate and controllability of targeting delivery of the nature products nanosuspensions.

Antifungal Encapsulated into Ligand-Functionalized Nanoparticles with High Specificity for Macrophages

Infectious diseases caused by intracellular microorganisms such as Histoplasma capsulatum represent a significant challenge worldwide. Drug encapsulation into functionalized nanoparticles (NPs) is a valuable alternative to improving drug solubility and bioavailability, preventing undesirable interactions and drug degradation, and reaching the specific therapeutic target with lower doses. This work reports on Itraconazole (ITZ) encapsulated into core-shell-like polymeric NPs and functionalized with anti-F4/80 antibodies for their targeted and controlled release into macrophages. Uptake assay on co-culture showed significant differences between the uptake of functionalized and bare NPs, higher with functionalized NPs. In vitro assays showed that F4/80-NPs with 0.007 µg/mL of encapsulated ITZ eliminated the H. capsulatum fungus in co-culture with macrophages effectively compared to the bare NPs, without any cytotoxic effect on macrophages after 24 h interaction. Furthermore, encapsulated ITZ modulated the gene expression of anti and pro-inflammatory cytokines (IL-1, INF-Y, IL-6 and IL-10) on macrophages. Additionally, the anti-F4/80 antibody-coating enhanced natural and adequate antifungal response in the cells, exerting a synergistic effect that prevented the growth of the fungus at the intracellular level. Functionalized NPs can potentially improve macrophage-targeted therapy, increasing NPs endocytosis and intracellular drug concentration.

Biological and Intracellular Fates of Drug Nanocrystals through Different Delivery Routes: Recent Development Enabled by Bioimaging and PK Modeling

Nanocrystals have contributed to exciting improvements in the delivery of poorly water-soluble drugs. The biological and intracellular fates of nanocrystals are currently under debate. Due to the remarkable commercial success in enhancing oral bioavailability, nanocrystals have originally been regarded as a simple formulation approach to enhance dissolution. However, the latest findings from novel bioimaging tools lead to an expanded view. Intact nanocrystals may offer long-term durability in the body and offer drug delivery capabilities like those of other nano-carriers. This review renews the understanding of the biological fates of nanocrystals administered via oral, intravenous, and parenteral (e.g., dermal, ocular, and pulmonary) routes. The intracellular pathways and dissolution kinetics of nanocrystals are explored. Additionally, the future trends for in vitro and in vivo quantification of nanocrystals, as well as factors impacting the biological and intracellular fates of nanocrystals are discussed. In conclusion, nanocrystals present a promising and underexplored therapeutic opportunity with immense potential.

Functionalized niosomes as a smart delivery device in cancer and fungal infection

Various diseases remain untreated due to lack of suitable therapeutic moiety or a suitable drug delivery device, especially where toxicities and side effects are the primary reason for concern. Cancer and fungal infections are diseases where treatment schedules are not completed due to severe side effects or lengthy treatment protocols. Advanced treatment approaches such as active targeting and inhibition of angiogenesis may be preferred method for the treatment for malignancy over the conventional method. Niosomes may be a better alternative drug delivery carrier for various therapeutic moieties (either hydrophilic or hydrophobic) and also due to ease of surface modification, non-immunogenicity and economical. Active targeting approach may be done by targeting the receptors through coupling of suitable ligand on niosomal surface. Moreover, various receptors (CD44, folate, epidermal growth factor receptor (EGFR) & Vascular growth factor receptor (VGFR)) expressed by malignant cells have also been reviewed. The preparation of suitable niosomal formulation also requires considerable attention, and its formulation depends upon various factors such as selection of non-ionic surfactant, method of fabrication, and fabrication parameters. A combination therapy (dual drug and immunotherapy) has been proposed for the treatment of fungal infection with special consideration for surface modification with suitable ligand on niosomal surface to sensitize the receptors (C-type lectin receptors, Toll-like receptors & Nucleotide-binding oligomerization domain-like receptors) present on immune cells involved in fungal immunity. Certain gene silencing concept has also been discussed as an advanced alternative treatment for cancer by silencing the mRNA at molecular level using short interfering RNA (si-RNA).

Preparation and antitumor evaluation of quercetin nanosuspensions with synergistic efficacy and regulating immunity

To study the effect of quercetin (QUR) on modulating immune effects, enhancing anti-tumor activity, and reducing drug related side effects, three QUR nanosuspensions (QUR-NPs) with different particle sizes were prepared by a microprecipitation-high pressure homogenization method using mPEG-DCA as a stabilizer. Dynamic light scattering was used to analyze the particle sizes of the three QUR-NPs. The results of stability tests showed that the three QUR-NPs had good storage and plasma stability. It was confirmed that plasma protein adsorption occurred for all three QUR-NPs. The results of DSC, DTG, XRPD, and Raman spectroscopy showed that there was no significant change in the crystal form of QUR for any of the three QUR-NPs compared with the commercial QUR. The in vitro dissolution rate of the three QUR-NPs was significantly faster than that of the micronized QUR, with the dissolution rate increasing as particle size decreased. All three QUR-NPs showed stronger in vitro inhibitory activity on MCF-7 cells than the pure QUR solution, with the largest NPs having the strongest inhibitory effect. The pharmacokinetic parameters in rats showed that the MRT and t_1/2 of the QUR-NPs increased as particle size increased. QUR-NPs and the pure QUR solution showed obvious anti-tumor effects against murine hepatic carcinoma H22 model in vivo, although they were not as effective as cyclophosphamide (CTX). However, the anti-tumor effect of the large QUR-NPs combined with CTX was the strongest among all the tested groups. From the results of the thymus and spleen index, it was found that the QUR-NPs could not only regulate the immunity of tumor-bearing mice, but also alleviate the immunosuppression caused by CTX and protect normal tissues, all while enhancing the anti-tumor effect. The immunomodulatory effect of the QUR-NPs on tumor-bearing mice was significantly better than that of the pure QUR solution. Therefore, nanosuspensions can be used as a new drug delivery system for QUR to assist tumor therapy and regulate immunity.

Sea cucumbers-derived sterol sulfate alleviates insulin resistance and inflammation in high-fat-high-fructose diet-induced obese mice

Sea cucumbers are widely consumed in traditional medicine and food. Sea cucumbers-derived sulfated sterol exhibits a sulfate group at C-3 position, which is different from phytosterol with a hydroxyl group. However, the effect of sterol sulfate on metabolic syndrome remains unknown. The purpose of the present study is to investigate the alleviation of sterol sulfate on high-fat-high-fructose diet (HFFD)-induced insulin resistance and inflammation. After 2 weeks feeding with HFFD, male C57BL/6J mice were continuously fed with HFFD plus 0.4 % (w/w) sterol sulfate or phytosterol for 6 weeks. The OGTT was carried out at 7 weeks. At the end of the experimental period, the changes of glycogen, circulating glucose, insulin, pro-inflammatory cytokine and adiponectin were measured. H&E staining was used to observe the morphological changes in adipose tissue. Furthermore, the underlying molecular mechanisms were investigated. Dietary sterol sulfate was superior to phytosterol in reducing body weight gain, adipocyte hypertrophy, and levels of circulating glucose and insulin, as well as increasing the glycogen content of tissues. Furthermore, sterol sulfate ameliorated insulin resistance mainly due to the inhibition of gluconeogenesis, the promotion of glycogen synthesis and GLUT4 translocation by activating PI3K/Akt signaling pathway. Additionally, sterol sulfate effectively attenuated inflammation by increasing serum adiponectin and reducing pro-inflammatory cytokine release. Sterol sulfate exhibited a more significant effect than phytosterol in alleviating HFFD -induced insulin resistance and inflammation, which might be closely related to the sulfate group. The results might provide insights into the prevention and alleviation of metabolic syndrome.

Formulation aspects of intravenous nanosuspensions

Intravenous (IV) route is preferred for rapid onset of action, avoiding first pass metabolism and achieving site specific delivery. Development of IV formulations for poorly water soluble drugs poses significant challenges. Formulation approaches like salt formation, co-solvents, surfactants and inclusion complexation using cyclodextrins are used for solubilisation. However, these approaches are not applicable universally and have limitations in extent of solubilisation, hypersensitivity, toxicity and application to only specific type of molecules. IV nanosuspension have been attracting attention as a viable strategy for development of IV formulations of poorly water-soluble drugs. Nanosuspension consists of nanocrystals of poorly water soluble drug suspended in aqueous media and stabilized using minimal concentration of stabilizers. Recent years have witnessed their potential in formulations for toxicological studies and clinical trials. However various challenges are associated with the translational development of IV nanosuspensions. Therefore, the objective of the current review is to provide a holistic view of formulation development and desired properties of IV nanosuspensions. It will also focus on advancements in characterization tools, manufacturing techniques and post-production processing. Challenges associated with translational development and regulatory aspects of IV nanosuspension will be addressed. Additionally, their role in preclinical evaluation and special applications like targeting will also be discussed with the help of case studies. The applications of IV nanosuspensions shall expand as their applications move from preclinical phase to commercialization.