Desirable PEGylation for improving tumor selectivity of hyaluronic acid-based nanoparticles via low hepatic captured, long circulation times and CD44 receptor-mediated tumor targeting.

PEG coating was regarded as one effective method to improve the tumor-targeting efficiency of hyaluronic acid-based nanoparticles (HBN). However, the research of interaction between PEG coating and different receptors such as stabilin-2 and CD44 was limited. Herein, we synthesized a series of PEGylated hyaluronic acid with Curcumin (PHCs) to evaluate the role of PEG coating density in the interaction between HA and its receptors, which influenced tissues targeting activity, pharmacokinetic profiles and therapeutic efficacy of HBN. Compared with other counterparts, PHC HBN with about 5% PEG coating density preferably accumulated in the tumor mass, rather than in the liver, and hold desirable anti-cancer effect. These results indicated that to obtain optimized anticancer effect of HBN, the cellular uptake efficiency between different types of the cells should be carefully balanced by different PEG densities.

A sensitive LC-MS/MS method for simultaneous determination of cabozantinib and its metabolite cabozantinib N-oxide in rat plasma and its application in a pharmacokinetic study.

Cabozantinib (CBZ) is used for the treatment of progressive, metastatic medullary thyroid cancer. Its major oxidative metabolite is cabozantinib N-oxide (CBN), which contains a structural alert associated with mutagenicity, yet the pharmacokinetics studies lack the simultaneous investigation of CBN and dose proportionality. In the current study a simple LC-MS/MS method was developed and validated for the simultaneous estimation and pharmacokinetic investigation of CBZ and CBN in rat plasma. The analytes were separated on a Waters Atlantics C18 column (2.1 × 150 mm, 3 µm). The mass spectrometry analysis was conducted in positive ionization mode with multiple reaction monitoring. Good linearity was observed over the concentration ranges of 0.500-5000 ng/mL for CBZ and 0.525-2100 ng/mL for CBN. The extraction recoveries were constant and the intra- and inter-batch precision and accuracy were acceptable for the analysis of biological samples. The method was successfully applied for the simultaneous estimation of CBZ and CBN in a pharmacokinetic study in Sprague-Dawley rats. After oral administration of CBZ (1, 5 and 12.6 mg/kg), although CBZ showed dose proportionality, the metabolite CBN showed obvious nonlinear elimination pharmacokinetics with greater than dose-proportional increases in exposure.

[Research & development and evaluation of oral films].

Oral film is a new type of oral preparation. Due to portability, simple preparation process and good clinical compliance, oral films have become the focus of novel drug delivery system in recent years. Meanwhile, oral films have been gradually used in the development of Chinese medicine preparations. According to the application and approval situation of different types of oral films both at home and abroad in recent years, their research and development status was analyzed, including the basic concept, formulation, manufacturing process and quality control, as well as related progress and development prospects of oral films applied in traditional Chinese medicine. Some suggestions on the technical evaluation of oral films were put forward by considering specific requirements from regulatory agencies. This paper could provide some references for the development and evaluation of oral films. Due to the complexity of the drug substances and the particularity of the drug product, the development and application of oral films in traditional Chinese medicine are still faced with opportunity and challenges.

ROS-scavenging nanomedicine for "multiple crosstalk" modulation in non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is a chronic inflammatory disease characterized by "multiple crosstalk" paths of insulin resistance, lipid metabolism, oxidative stress, etc. The combination of LY294002 and oridonin was proposed as a promising therapy by targeting insulin-PI3K/AKT signaling and NF-κB inflammatory pathway. However, due to oxidative stress, disease-associated upregulation of murine CYP3A11 activity can contribute to unexpected drug metabolism and disposition, which could seriously hinder the efficacy of LY294002 and oridonin. Nanotechnology-based effective reactive oxygen species (ROS) scavengers have emerged as a promising strategy to overcome these limitations. In this study, a rationally designed ROS-responsive liposome loaded with oridonin and LY294002 (RLLs) was developed for effective liver deposition and metabolic regulation for NAFLD treatment. First, we ascertained that the insulin resistance-induced signaling response was balanced by the combination of LY294002 and oridonin. Then, the particle size, zeta potential, ROS-responsive release behavior, and ROS-scavenging properties were investigated. Moreover, the CCl4-exposed mouse model was used to assess the biodistribution and therapeutic efficacy of RLLs on NAFLD. Finally, the "multiple crosstalk" modulation of RLLs was explored by western blotting, enzyme-linked immunosorbent assay, and polymerase chain reaction analysis. RLLs exhibited antioxidant efficacy for the safe delivery of LY294002 and oridonin with good stability and biocompatibility. The biodistribution analysis proved that the accumulation of RLLs was significantly increased due to CD44-mediated targeting. In addition, RLLs had comprehensive protective effects on the CCl4-exposed mouse model, leading to significant elimination of excessive ROS, maintenance of insulin sensitivity and CYP450 activity, and reduction of inflammatory response. In the CCl4-induced mice, RLL intervention remarkably improved metabolic profiles and reduced the fibrosis lesions. Our results provided a strategy for the amelioration of oxidative stress and CYP450 activity using ROS-responsive thioketal as an antioxidant adjuvant facilitated by nanotechnology.

Evolution of drug regulations and regulatory innovation for anticancer drugs in China.

Over the past two decades, China has introduced significant changes to drug regulations through regulatory innovations to accelerate drug review and approvals, keeping in line with the rapidly growing scientific innovation in drug research and development (R&D). In this study, we outlined the revolution of drug regulation in China since the establishment of the State Drug Administration in 1998. More particularly, we performed a comprehensive analysis of newly approved anticancer drugs in China from the year 2005 to May 2021, as a powerful illustration of how the revolution has changed the drug R&D landscape. Innovative drug development in China has boomed, benefiting in particular from pro-innovation policies as well as expedited program designations by the authority. We found a significant increase in the number of both imported and domestic new anticancer drugs from 2005 to 2021, with the emergence of drugs with novel mechanisms of action, including immune checkpoint inhibitors and cell therapy products. Drug lag has also been dramatically shortened by more than 70% for imported drugs in years 2016-2020 compared to years 2006-2010. Furthermore, we provide an insight into the potential approaches to further optimize the science-based and clinical value-based regulatory and R&D drug ecosystem in China. This review provides evidence of significant impacts of regulations and policies on drug R&D and suggests that the constantly adapting regulatory ecosystem will speed up drug development in China and worldwide.

Liposomal remdesivir inhalation solution for targeted lung delivery as a novel therapeutic approach for COVID-19.

Strong infectivity enables coronavirus disease 2019 (COVID-19) to rage throughout the world. Moreover, the lack of drugs with definite therapeutic effects further aggravates the spread of the pandemic. Remdesivir is one of the most promising anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) drugs. However, the limited clinical effects make its therapeutic effect controversial, which may result from the poor accumulation and activation of remdesivir in the lung. Therefore, we developed lyophilized remdesivir liposomes (Rdv-lips) which can be reconstituted as liposomal aerosol for pulmonary delivery to improve the in vivo behavior of existing remdesivir cyclodextrin conclusion compound (Rdv-cyc) injections. Liposome encapsulation endowed remdesivir with much higher solubility and better biocompatibility. The in vitro liposomal aerosol characterization demonstrated that Rdv-lips possessed a mass median aerodynamic diameter of 4.118 µm and fine particle fraction (<5 µm) higher than 50%, indicating good pulmonary delivery properties. Compared to the Rdv-cyc intravenous injection group, the Rdv-lips inhalation group displayed a nearly 100-fold increase in the remdesivir-active metabolite nucleotide triphosphate (NTP) concentration and better NTP accumulation in the lung than the Rdv-cyc inhalation group. A faster transition from remdesivir to NTP of Rdv-lips (inhalation) could also be observed due to better cell uptake. Compared to other preparations, the superiority of Rdv-lips was further evidenced by the results of an in vivo safety study, with little possibility of inducing inflammation. In conclusion, Rdv-lips for pulmonary delivery will be a potent formulation to improve the in vivo behavior of remdesivir and exert better therapeutic effects in COVID-19 treatment.

Resolving hepatic fibrosis via suppressing oxidative stress and an inflammatory response using a novel hyaluronic acid modified nanocomplex.

Hepatic fibrosis remains a serious threat to human health globally and there are no effective antifibrotic pharmacotherapeutic strategies, to date. Upon the activation of hepatic stellate cells, excess deposition of the extracellular matrix occurs, acting as a trigger that generates reactive oxygen species and an inflammatory response, thereby exacerbating the development of hepatic fibrosis and inflammation. In this study, we incorporated an idea that targets key pathways for developing novel anti-fibrosis nanomedicine. Previous studies have reported the potential of LY294002 (LY) as a PI3K/Akt inhibitor that suppresses the HSC activation and fibrosis development; however, its poor water solubility impedes further investigation. Moreover, the proliferation of HSC, severe oxidative stress and inflammatory conditions could be undermined by oridonin (ORD) treatment. Herein, we developed an HA-ORD/LY-Lips nanocomplex, where LY294002 was encapsulated into liposomes to prepare LY-Lips while ORD was conjugated with a hyaluronic acid (HA) polymer acting as a prodrug HA-ORD. The complex exerts great potential in improving the liver-targeted drug release. We adopted a series of in vitro and in vivo evaluations which demonstrate that HA-ORD/LY-Lips can significantly avert activation of hepatic stellate cells via scavenging reactive oxygen species and suppressing an inflammatory response. Our work implements a proof of concept strategy for fibrosis treatment based on the dual antioxidative and anti-inflammatory mechanisms, which may be applicable to treat liver fibrosis associated with a dysregulated inflammatory microenvironment.

Fibroblast activation protein-α-adaptive micelles deliver anti-cancer drugs and reprogram stroma fibrosis.

Cancer-associated fibroblasts (CAFs) are the majority cell population of tumor stroma, and they not only play important roles in tumor growth and metastasis, but they also form a protective physical barrier for cancer cells. Herein, we designed a fibroblast activation protein-α (FAP-α)-adaptive polymeric micelle based on hyaluronic acid and curcumin conjugates. The polymeric micelle is composed of a CD44-targeting shell and a FAP-α-cleavable polyethylene glycol (PEG) coating. When FAP-α is encountered on the surface of CAFs in the tumor microenvironment, the PEG layer is released, hyaluronic acid is recovered on the surface of nanoparticles, and the nanoparticles effectively inhibit the growth of tumor cells and CAFs through CD44-mediated endocytosis. The FAP-α-adaptive polymeric micelle exhibited potent anti-cancer efficacy by enhancing CAF apoptosis and reducing collagen in tumor tissues. Collectively, FAP-α-adaptive nanoparticles may be a promising method for antitumor anticancer treatments via reprogramming of stroma fibrosis.

Doxorubicin delivered by redox-responsive Hyaluronic Acid-Ibuprofen prodrug micelles for treatment of metastatic breast cancer.

During the process of cancer metastasis, various enzymes, cytokines, and factors were involved, and upregulated cyclooxygenase-2(COX-2) in tumor cells led to proliferation and invasion of various tumors. Many nonsteroidal anti-inflammatory drugs (NSAIDs) were used as an anticancer adjuvant in chemotherapy, such as ibuprofen (BF) and celecoxib. NSAIDs could effectively inhibit local inflammation and decreased COX-2 expression. However, most of them have serious toxicity issues due to their limit selectivity against cancer and poor water solubility. Thus hyaluronic acid-ibuprofen (HA-ss-BF), which was sensitive to the reducing environment, was prepared by binding ibuprofen (BF) to the hyaluronic acid backbone through a disulfide bond, and the HA-ss-BF polymer could self-assemble into micelles and serve as carriers to delivery doxorubicin. These redox-sensitive prodrug polymeric micelles hold multiple therapeutic advantages, including on-demand BF release and disassembling micelles responding to redox stimuli, as well as desirable cellular uptake and favorable biodistribution. These advantages indicated the redox-responsive hyaluronic acid-ibuprofen prodrug could be a promising delivery system for metastatic breast cancer treatment.

Development and validation of a highly sensitive LC-MS/MS method for determination of brain active agent dianhydrogalactitol in mouse plasma and tissues: Application to a pharmacokinetic study.

A sensitive and specific liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) method was developed and validated for quantitative analysis of 1,2:5,6-dianhydrogalactitol (DAG) in mouse plasma and tissues. Sodium diethyldithiocarbamate (DDTC) was used as the derivatization reagent to improve its LC-MS/MS behavior. Analytes were separated on a Welch Ultimate XB-CN column with a mobile phase consisting of acetonitrile and 0.1% formic acid solution (65:35). The MS analysis was conducted by positive electrospray ionization in multiple-reaction monitoring (MRM) mode. Good linearity (r2 > 0.9958) was observed over the concentration range of 1-1000 ng/mL in plasma and tissue homogenates (brain, liver, heart, spleen, lung and kidney). The intra- and inter-batch precision and accuracy of DAG in plasma and brain samples were all within the acceptable limits. The extraction recovery was stable and no significant matrix effects were observed. The method was successfully applied to study the pharmacokinetic and tissue distribution of DAG in mice after intravenous administration. DAG could cross the blood-brain barrier and had limited liver distribution. Rat primary hepatocytes in vitro experiments demonstrated that DAG had a safe profile in liver.