Insufficient Drug Concentrations Research Articles

Abstract 7163: Pharmacokinetics assessment of intranasal NEO100 treatment on blood-brain barrier disruption and brain penetration of drugs in rodent brain

Abstract Background: Insufficient drug concentrations reaching the brain-localized tumor tissue remains one of the major challenges in the treatment of glioblastoma (GBM). An intranasal (IN) formulation of NEO100 (NeOnc Technologies, Inc., Los Angeles), a highly purified version of perillyl alcohol, has been recently reported to enhance drug concentrations in the brain upon IN co-delivery. Here, we report detailed pharmacokinetics (PK) and tissue analysis to quantitatively examine the extent of increase in drug concentrations in the brain after IN NEO100 administration. Furthermore, we also confirmed that IN NEO100 increases brain drug concentration by circumventing the blood brain barrier. Method: For PK analysis, either IN or oral formulation of a three-drug cocktail (ZEI, consisting of ZN-c3, everolimus, and infigratinib) was used to evaluate the impact of 3% IN NEO100 on the brain penetration profile of the three individual drugs. Athymic mice were grouped into four cohorts to receive 1) oral ZEI; 2) IN ZEI; 3) oral ZEI with IN NEO100; and 4) IN ZEI with IN NEO100. At 2, 4 and 6 hours post ZEI dosing, drug levels in plasma and brain tissue were measured by liquid chromatography tandem mass spectrometry (LC-MS/MS). For BBB disruption study, athymic mice were treated with IN delivery of saline (negative control) or 3% NEO100 one hour post intravenous Evans blue (2%) administration. Tumor bearing mice with disrupted BBB served as positive control. Two hours post Evans blue administration, animals were perfused, and brains were collected and sectioned for confocal microscopy to image Evan’s blue autofluorescence. Results: PK analysis revealed that brain-to-plasma ratios (Kp) for ZN-c3, everolimus, and infigratinib remained nearly equal, independent of the route of administration, i.e. 0.11, 0.03, and 0.82 vs 0.09, 0.03, and 0.87, for IN vs oral routes, respectively. Administration of the ZEI together with IN NEO100, either through oral or IN routes, resulted in higher drug concentrations, both in the plasma and in the brain. However, while overall drug exposure was increased, Kp values of the drugs were not changed. Confocal imaging of brains from mice treated with 3% IN NEO100 did not show presence of Evans blue autofluorescence while positive control mice with disrupted BBB within the tumor core displayed high Evans blue fluorescence. Conclusions: Co-administration of IN NEO100 with ZN-c3, everolimus, and infigratinib increases their brain and plasma exposure. As a result, no significant increase in brain-to-plasma partition was registered for any of the three drugs tested in this study. IN NEO100-mediated increase in brain drug concentration was independent of BBB disruption Citation Format: Anil Thaghalli Shivanna, Tigran Margaryan, Mariya Stavnichuk, William Knight, Sonam Patel, Elaine Cabrales, An-Chi Tien, Thomas Chen, Nader Sanai, Artak Tovmasyan, Shwetal Mehta. Pharmacokinetics assessment of intranasal NEO100 treatment on blood-brain barrier disruption and brain penetration of drugs in rodent brain [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7163.

Multifunctional Sr/Se co-doped ZIF-8 nanozyme for chemo/chemodynamic synergistic tumor therapy via apoptosis and ferroptosis.

Rationale: Cancer continues to be a significant public health issue. Traditional treatments such as surgery, radiotherapy, and chemotherapy often fall short because of intrinsic issues such as lack of specificity and poor drug delivery, leading to insufficient drug concentration at the tumor site and/or potential side effects. Consequently, improving the delivery of conventional chemotherapy drugs like doxorubicin (DOX) is crucial for their therapeutic efficacy. Successful cancer treatment is achieved when regulated cell death (RCD) of cancer cells, which includes apoptotic and non-apoptotic processes such as ferroptosis, is fundamental to successful cancer treatment. The developing field of nanozymes holds considerable promise for innovative cancer treatment approaches. Methods: A dual-metallic nanozyme system encapsulated with DOX was created, derived from metal-organic frameworks (MOFs), designed to combat tumors by depleting glutathione (GSH) and concurrently liberating DOX. The initial phase of the study examined the GSH oxidase-mimicking function of the dimetallic nanozyme (ZIF-8/SrSe) through enzyme kinetic assays and Density Functional Theory (DFT) simulations. Following this, we probed the ability of ZIF-8/SrSe@DOX to release DOX in response to the tumor microenvironment in vitro, alongside examining its anticancer capabilities and mechanisms prompting apoptosis or ferroptosis in cancer cells. Moreover, we established tumor-bearing animal models to corroborate the anti-tumor effectiveness of our nanozyme complex and to identify the involved apoptotic and ferroptotic pathways implicated. Results: Enzyme kinetic analyses demonstrated that the ZIF-8/SrSe nanozyme exhibits substantial GSH oxidase-like activity, effectively oxidizing reduced GSH to glutathione disulfide (GSSG), while also inhibiting glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11). This inhibition led to an imbalance in iron homeostasis, pronounced caspase activation, and subsequent induction of apoptosis and ferroptosis in tumor cells. Additionally, the ZIF-8/SrSe@DOX nanoparticles efficiently delivered DOX, causing DNA damage and further promoting apoptotic and ferroptotic pathways. Conclusions: This research outlines the design of a novel platform that combines chemotherapeutic agents with a Fenton reaction catalyst, offering a promising strategy for cancer therapy that leverages the synergistic effects of apoptosis and ferroptosis.

Combined medical-interventional approaches for the management of complex fungal balls: a case series as a viable alternative in non-surgical patients.

Intracavitary pulmonary aspergilloma is a persistent and life-threatening infection that carries a mortality rate of up to 15%. It occurs when Aspergillus species gain entry to an existing lung cavity. In the absence of definitive treatment, patients may succumb to severe complications such as massive hemoptysis, cachexia, or secondary infections. Aspergillomas often show limited response to antifungal medications, mainly due to insufficient drug concentrations within the cavities. Surgery is frequently the preferred treatment option, but it poses significant risks, and many individuals are ineligible due to underlying health issues. We present the most extensive non-surgical fungal ball cohort to date, managed using an innovative multimodal strategy that combines antifungal therapy before and after bronchoscopic debulking. This was a cross-sectional observational study. For those who cannot undergo surgery, our medical center has pioneered a multimodal approach to aspergilloma resection. This approach combines bronchoscopic endoscopy with antifungal therapy and has been applied successfully to more than 18 patients that are presented in this series. The median age of the cohort was 58 years (range: 32-73), with an equal sex distribution. The mean percent predicted FEV1 was 65.3%. The mean follow-up duration was 3.6 years (range: 0.5-10 years). The cohort receiving antifungals systematically prior to debridement showed a reduction of the pre-existing cavity (40.38 mm versus 34.02 mm, p = 0.021). Across the 18 patients during the follow-up period, 94% remained recurrence-free (defined by symptoms and radiology). Our study fills a critical knowledge gap regarding the significance of initiating antifungal treatment before bronchoscopic debulking and presents a viable approach in these cases for which there is a current unmet therapeutic need.

Ligand-mediated Targeted Drug Delivery Approaches against Hepatocellular Carcinoma.

One of the most important health problems in the world today is cancer. The World Health Organization (WHO) reported that it results in 8.9 million deaths annually. Malignant tumours and unregulated cell proliferation are features of malignant neoplasms, which can also invade nearby body regions. Hepatocellular carcinoma is the third most prevalent cause of cancer-related death worldwide and the fifth most common kind of cancer, according to a recent analysis. Patients with liver disease as well as chronic hepatitis B and C are more likely to develop hepatocellular carcinoma (HCC). Physical barriers, including RES absorption, opsonization, and first-pass drug metabolism, make drug therapy more challenging. Conventional cancer therapy procedures have a low response rate or may continue to be unsuccessful due to multi-drug resistance (MDR), high clearance rates, and other side effects because of suboptimal drug distribution and insufficient drug concentration reaching cancer cells. Innovative target drug molecules that are tailored to the injured liver cells must be developed in order to improve medication administration and drug targeting. The use of targeting ligands that have been joined to drug molecules or nanocarriers forms the basis of innovative targeting techniques. After being conjugated with the treatment method, ligands for targeting hepatocellular carcinoma cells included asialoglycoprotein, galactoside, lactobionic acid, mannose-6-phosphate, PDGF, antibodies, and aptamers.

Development and in vitro evaluation of carmustine delivery platform: A hypoxia-sensitive anti-drug resistant nanomicelle with BBB penetrating ability

Glioma is extremely difficult to be completely excised by surgery due to its invasive nature. Thus, chemotherapy still is the mainstay in the treatment of glioma after surgery. However, the natural blood-brain barrier (BBB) greatly restricts the penetration of chemotherapeutic agents into the central nervous system. As a front-line anti-glioma agent in clinical, carmustine (BCNU) exerts antitumor effect by inducing DNA damage at the O6 position of guanine. However, the therapeutic effect of BCNU was largely decreased because of the drug resistance mediated by O6-alkylguanine-DNA alkyltransferase (AGT) and insufficient local drug concentrations. To overcome these obstacles, we synthesized a BCNU-loaded hypoxia-responsive nano-micelle with BBB penetrating capacity and AGT inhibitory activity, named as T80-HA-AZO-BG/BCNU NPs. In this nano-system, Tween 80 (T80) serves as a functional coating on the surface of the micelle, promoting transportation across the BBB. Hyaluronic acid (HA) with active tumor-targeting capability was linked with the hydrophobic O6-benzylguanine (BG) analog via a hypoxia-sensitive azo bond. Under hypoxic tumor microenvironment, the azo bond selectively breaks to release O6-BG as AGT inhibitor and BCNU as DNA alkylating agent. The synthesized T80-HA-AZO-BG/BCNU NPs showed good stability, favorable biocompatibility and hypoxia-responsive drug-releasing ability. T80 modification improved the transportation of the micelle across an in vitro BBB model. Moreover, T80-HA-AZO-BG/BCNU NPs exhibited significantly enhanced cytotoxicity against glioma cell lines with high AGT expression compared with traditional combined medication of BCNU plus O6-BG. We expect that the tumor-targeting nano-micelle designed for chloroethylnitrosourea will provide new tools for the development of effective glioma therapy.

Posaconazole exposure in critically ill ICU patients: a need for action

PurposePosaconazole is an antifungal drug currently being used for prophylaxis and treatment of invasive fungal infections such as aspergillosis. To date, therapeutic drug monitoring (TDM) of posaconazole is recommended with the use of oral suspension, but the potential need of TDM with the use of IV formulations is rising. Therefore, we aimed to investigate the pharmacokinetics of IV posaconazole in critically ill patients.MethodsIn a prospective study, we analysed 168 consecutivelly collected posaconazole levels from 10 critically ill patients drawn during a 7 day curse. Posaconazole concentrations were measured using a chromatographic method. Demographic and laboratory data were collected, and the data was analysed using descriptive statistics.ResultsWe included 168 posaconazole levels, resulting in a median trough of 0.62 [0.29–1.05] mg/L with 58% not reaching the suggested target of 0.5 mg/L for fungal prophylaxis. Moreover, 74% of the trough levels were under the target of 1 mg/L which is proposed for the treatment of aspergillosis.ConclusionPosaconazole exposure is highly variable in critically ill patients resulting in potentially insufficient drug concentrations in many cases. TDM is highly recommended to identify and avoid underexposure.Trial registration numberNCT05275179, March 11, 2022.

Nanomaterials-mediated on-demand and precise antibacterial therapies

Bacterial infection is a series of pathological changes caused by bacteria invading the host and interacting with the body. Nowadays, bacterial infection remains a major public health issue and a severe threat to human life and health. Traditional antibiotic therapy is less effective against biofilms and easily causes bacterial resistance, which has urged the development of a substitute antibacterial strategy. Recently, antibacterial nanomaterials have attracted much attention. However, traditional nanomaterials face some problems of insufficient drug concentration at infectious sites and the toxicity of extravasated drug causes damage to healthy tissues. On the contrary, nanomaterials based on advanced on-demand and precise strategies reduce biological toxicity effectively while improving germicidal efficacy, since these type of nanodrugs have higher spatiotemporal controllability. Currently, some smart stimuli-responsive nanomaterials and targeting nanomaterials have been successfully constructed to achieve on-demand and precise antibacterial therapies. This review focuses on the mechanisms, working principles and antimicrobial properties of diverse nanoparticles based on on-demand and precise strategies. Meanwhile, the strengths and inferiorities of different on-demand and precise strategies have been discussed. Finally, this review concludes with our opinions on the future development directions for exploiting next-generation on-demand and precise antibacterial therapies.

Hollow MnO2-Based Nanoprobes for Enhanced Photothermal/Photodynamic /Chemodynamic Co-Therapy of Hepatocellular Carcinoma

The effect of monotherapy in cancer is frequently influenced by the tumor's unique hypoxic microenvironment, insufficient drug concentration at the treatment site, and tumour cells' increased drug tolerance. In this work, we expect to design a novel therapeutic nanoprobe with the ability to solve these problems and improve the efficacy of antitumor therapy. We have prepared a hollow manganese dioxide nanoprobes loaded with photosensitive drug IR780 for the photothermal/photodynamic/chemodynamic co-therapy of liver cancer. The nanoprobe demonstrates efficient thermal transformation ability under a single laser irradiation, and under the synergistic influence of photo heat, accelerates the Fenton/ Fenton-like reaction efficiency based on Mn2+ ions to produce more ·OH under the synergistic effect of photo heat. Moreover, the oxygen released under the degradation of manganese dioxide further promotes the ability of photosensitive drugs to produce singlet oxygen (ROS). The nanoprobe has been found to efficiently destroy tumour cells in vivo and in vitro experiments when used in combination with photothermal/photodynamic/ chemodynamic modes of treatment under laser irradiation. In all, this research shows that a therapeutic strategy based on this nanoprobe could be a viable alternative for cancer treatment in the near future.

Idarubicin-loaded biodegradable microspheres enhance sensitivity to anti-PD1 immunotherapy in transcatheter arterial chemoembolization of hepatocellular carcinoma.

Transarterial chemoembolization (TACE) is an image-guided locoregional therapy used for the treatment of patients with primary hepatocellular carcinoma (HCC). However, conventional TACE formulations such as epirubicin-lipiodol emulsion are rapidly dissociated due to the instability of the emulsion, resulting in insufficient local drug concentrations in the target tumor. To overcome these limitations, we used biodegradable Idarubicin loaded microspheres (BILMs), which were prepared from gelatin and carrageenan and could be loaded with Idarubicin (IDA-MS). The morphology and the ability to load and release IDA of BILMs were characterized in vitro. We evaluated tumor changes and side effects after TACE treatment with IDA-MS in VX2 rabbit and C57BL/6 mice HCC models. In addition, the effect of IDA-MS on the tumor immune microenvironment of HCC tumors was elucidated via mass spectrometry and immunohistochemistry. Result showed that IDA-MS was developed as a new TACE formulation to overcome the poor delivery of drugs due to rapid elimination of the anticancer drug into the systemic circulation. We demonstrated in rabbits and mice HCC models that TACE with IDA-MS resulted in significant tumor shrinkage and no more severe adverse events than those observed in the IDA group. TACE with IDA-MS could also significantly enhance the sensitivity of anti-PD1 immunotherapy, improve the expression of CD8+ T cells, and activate the tumor immune microenvironment in HCC. This study provides a new approach for TACE therapy and immunotherapy and illuminates the future of HCC treatment. STATEMENT OF SIGNIFICANCE: Conventional transarterial chemoembolization (TACE) formulations are rapidly dissociated due to the instability of the emulsion, resulting in insufficient local drug concentrations in hepatocellular carcinoma (HCC). To overcome these limitations, we used biodegradable microspheres called BILMs, which could be loaded with Idarubicin (IDA-MS). We demonstrated in rabbits and mice HCC models that TACE with IDA-MS resulted in significant tumor shrinkage and no more severe adverse events than those observed in the IDA group. TACE with IDA-MS could also significantly enhance the sensitivity of anti-PD1 immunotherapy, improve the expression of CD8+ T cells, and activate the tumor immune microenvironment in HCC. This study provides a new approach for TACE therapy and immunotherapy and illuminates the future of HCC treatment.

Safety, Tolerability, and Pharmacokinetics of Nebulized Hydroxychloroquine: A Pilot Study in Healthy Volunteers.

Background: Early in the coronavirus disease 2019 (COVID-19) pandemic, hydroxychloroquine (HCQ) drew substantial attention as a potential COVID-19 treatment based on its antiviral and immunomodulatory effects in vitro. However, HCQ showed a lack of efficacy in vivo, and different groups of researchers attributed this failure to the insufficient drug concentration in the lung following oral administration (HCQ is only available in the market in the tablet form). Delivering HCQ by inhalation represents a more efficient route of administration to increase HCQ exposure in the lungs while minimizing systemic toxicity. In this pilot study, the safety, tolerability, and pharmacokinetics of HCQ nebulizer solution were evaluated in healthy volunteers. Methods: Twelve healthy participants were included in this study and were administered 2 mL of HCQ01 solution (equivalent to 25 mg of HCQ sulfate) through Aerogen® Solo, a vibrating mesh nebulizer. Local tolerability and systemic safety were assessed by forced expiratory volume in the first and second electrocardiograms, clinical laboratory results (e.g., hematology, biochemistry, and urinalysis), vital signs, and physical examinations. Thirteen blood samples were collected to determine HCQ01 systemic exposure before and until 6 hours after inhalation. Results: The inhalation of HCQ01 was well tolerated in all participants. The mean value of Cmax for the 12 participants was 9.66 ng/mL. Tmax occurred at around 4.8 minutes after inhalation and rapidly decreased thereafter. The reported systemic exposure was very low with a mean value of 5.28 (0.6-15.6) ng·h/mL. Conclusion: The low systemic concentrations of HCQ01 of 9.66 ng/mL reported by our study compared with 1 μg/mL previously predicted after 200 mg BID oral administration, and the safety and tolerability of HCQ01 administered as a single dose through nebulization, support the assessment of its efficacy, safety, and tolerability in further studies for the treatment of COVID-19.

Microemulsion-thermosensitive gel composites as in situ-forming drug reservoir for periodontitis tissue repair through alveolar bone and collagen regeneration strategy

A satisfactory clinical effect in treating periodontitis is often difficult to achieve by conventional non-surgical systemic drug delivery due to the narrow anatomical structure of the periodontal pocket and insufficient drug concentration at lesion sites. In addition, the feasibility of combating periodontal tissue lesions by restoring the alveolar bone and allowing collagen regeneration has not been fully explored. The objective of this study was to prepare a microemulsion integrating the anti-inflammatory and osteogenic active ingredients of baicalin and clove oil (BC-MEs). Then, the composite hydrogel obtained by mixing poloxamer 407 and 188 was used as the thermosensitive gel matrix to load BC-MEs and form a drug reservoir (Gel-BC-MEs) injectable in situ. Gel-BC-MEs exhibited a significant, sustained release of baicalin for 12 h, gelation temperature was 33.4 ± 0.36 °C, and pH was 5.45 ± 0.12. The experiment on a rat periodontitis model demonstrated that Gel-BC-MEs significantly improved periodontal tissue repair by collagen regeneration and osteogenesis by inhibiting osteoclast infiltration. This study proposes a novel strategy for periodontal tissue repair by enhancing the therapeutic potential of a microemulsion using an in situ nano-gel delivery system.

Preclinical testing of dabigatran in trypsin-dependent pancreatitis.

Pancreatitis, the inflammatory disorder of the pancreas, has no specific therapy. Genetic, biochemical, and animal model studies revealed that trypsin plays a central role in the onset and progression of pancreatitis. Here, we performed biochemical and preclinical mouse experiments to offer proof of concept that orally administered dabigatran etexilate can inhibit pancreatic trypsins and shows therapeutic efficacy in trypsin-dependent pancreatitis. We found that dabigatran competitively inhibited all human and mouse trypsin isoforms (Ki range 10-79 nM) and dabigatran plasma concentrations in mice given oral dabigatran etexilate well exceeded the Ki of trypsin inhibition. In the T7K24R trypsinogen mutant mouse model, a single oral gavage of dabigatran etexilate was effective against cerulein-induced progressive pancreatitis, with a high degree of histological normalization. In contrast, spontaneous pancreatitis in T7D23A mice, which carry a more aggressive trypsinogen mutation, was not ameliorated by dabigatran etexilate, given either as daily gavages or by mixing it with solid chow. Taken together, our observations showed that benzamidine derivatives such as dabigatran are potent trypsin inhibitors and show therapeutic activity against trypsin-dependent pancreatitis in T7K24R mice. Lack of efficacy in T7D23A mice is probably related to the more severe pathology and insufficient drug concentrations in the pancreas.

Nano-Chemotherapy synergize with immune checkpoint inhibitor- A better option?

Immune checkpoint inhibitor (ICI) is one of the most important tumor treatment methods. Although the therapeutic efficiency of immune checkpoint inhibitor mono-therapy is limited, the combination of chemotherapy plus immune checkpoint inhibitors has shown great advantages in cancer treatment. This is mainly due to the fact that tumor reactive T cells could fully provide their anti-tumor function as chemotherapy could not only cause immunogenic cell death to increase antigen presentation, but also improve the immunosuppressive tumor micro-environment to synergize with immune checkpoint inhibitors. However, traditional chemotherapy still has shortcomings such as insufficient drug concentration in tumor region, short drug duration, drug resistance, major adverse events, etc, which might lead to the failure of the therapy. Nano chemotherapeutic drugs, which refer to chemotherapeutic drugs loaded in nano-based drug delivery system, could overcome the above shortcomings of traditional chemotherapeutic drugs to further improve the therapeutic effect of immune checkpoint inhibitors on tumors. Therefore, the scheme of nano chemotherapeutic drugs combined with immune checkpoint inhibitors might lead to improved outcome of cancer patients compared with the scheme of traditional chemotherapy combined with immune checkpoint inhibitors.

Inhaled therapy for COVID-19: Considerations of drugs, formulations and devices

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent responsible for the COVID-19 pandemic, has outspread at full tilt across the world. Although several effective vaccines continue to be deployed, reliable antiviral treatments have yet to be developed against this disease. Currently, available therapeutics for COVID-19 include repurposed, and a few novel drugs. Many drugs have been promising in preclinical studies, but a majority of these drugs have shown little or no efficacy in clinical studies. One of the major reasons is the insufficient drug concentration in the lung, the primary target site of infection for SARS-CoV-2, from the administration of drugs through oral or intravenous routes. Higher effective doses administered through these routes could also lead to adverse side effects. For this reason, inhaled treatments are being tested as an efficient approach for COVID-19, allowing lower doses of drugs ensuring higher concentrations of the drug(s) in the lung. The inhaled treatment combining two or more antiviral drugs will increase potency and reduce the possibility of selecting for SARS-CoV-2 variants with reduced drug susceptibility. Finally, the appropriate drug combination needs to be delivered using a suitable system. Here, we review the current treatment for COVID-19 and their limitations, discussing the advantages of mono and combinational inhaled therapy with a brief outline of the recently reformulated anti-SARS-CoV-2 agents as inhaled formulations. The selection of appropriate delivery devices for inhalation and associated key considerations including the formulation challenges are also discussed.

Zoledronate combined metal-organic frameworks for bone-targeting and drugs deliveries

Medicine treatments for bone-related diseases such as osteoporosis, bone metastasis, osteomyelitis, and osteolysis are often limited by insufficient drug concentration at the lesion sites owing to the low perfusion of bone tissue. A carrier that can deliver multiple bone destruction site-targeting drugs is required to address this limitation. Here, we reported a novel bone-targeting nano-drug delivery platform formed by the integration of zoledronate (ZOL) and zeolitic imidazolate framework-8 (ZIF-8) nanoparticles. The ZOL mixed zeolitic imidazolate framework (ZZF) nanoparticles were synthesized in water at room temperature (25 °C), where many biomacromolecules could maintain their activity. This allowed the ZZF nanoparticles to adapt the encapsulation ability and pH response release property from ZIF-8 and the excellent bone targeting performance of ZOL simultaneously. Considering the ease of preparation and biomacromolecule-friendly drug delivery of this nano platform, it may be useful in treating bone-related diseases.

Macrophage membrane-biomimetic adhesive polycaprolactone nanocamptothecin for improving cancer-targeting efficiency and impairing metastasis

The recent remarkable success and safety of mRNA lipid nanoparticle technology for producing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines has stimulated intensive efforts to expand nanoparticle strategies to treat various diseases. Numerous synthetic nanoparticles have been developed for pharmaceutical delivery and cancer treatment. However, only a limited number of nanotherapies have enter clinical trials or are clinically approved. Systemically administered nanotherapies are likely to be sequestered by host mononuclear phagocyte system (MPS), resulting in suboptimal pharmacokinetics and insufficient drug concentrations in tumors. Bioinspired drug-delivery formulations have emerged as an alternative approach to evade the MPS and show potential to improve drug therapeutic efficacy. Here we developed a biodegradable polymer-conjugated camptothecin prodrug encapsulated in the plasma membrane of lipopolysaccharide-stimulated macrophages. Polymer conjugation revived the parent camptothecin agent (e.g., 7-ethyl-10-hydroxy-camptothecin), enabling lipid nanoparticle encapsulation. Furthermore, macrophage membrane cloaking transformed the nonadhesive lipid nanoparticles into bioadhesive nanocamptothecin, increasing the cellular uptake and tumor-tropic effects of this biomimetic therapy. When tested in a preclinical murine model of breast cancer, macrophage-camouflaged nanocamptothecin exhibited a higher level of tumor accumulation than uncoated nanoparticles. Furthermore, intravenous administration of the therapy effectively suppressed tumor growth and the metastatic burden without causing systematic toxicity. Our study describes a combinatorial strategy that uses polymeric prodrug design and cell membrane cloaking to achieve therapeutics with high efficacy and low toxicity. This approach might also be generally applicable to formulate other therapeutic candidates that are not compatible or miscible with biomimetic delivery carriers.

Presenting a bioactive nanotherapeutic agent for colon cancer treatment

Colon cancer (CC) is one of the major causes of death worldwide. Insufficient drug concentration, non-specificity, or serious adverse effects of the conventional chemotherapeutic agents necessitate application of more effective treatment options. Herein, poly-ursolic acid, a polymer with anticancer effect, has been self-assembled for producing nanoparticles (NPs) for delivery of irinotecan (IRN) which is usually associated with poor solubility and severe adverse effects. NPs showed therapeutic efficiency by themselves in vivo and in vitro. IRN-loaded NPs with appropriate physicochemical characteristics, released IRN in a controlled fashion and demonstrated more efficient cytotoxicity, lower clearance rate and distribution volume, higher Cmax and AUC, prolonged t1/2, increased accumulation in tumor, and therapeutic effects in vivo as compared to free drug. There was no significant alteration of body weight or damage to the major organs. The prepared bioactive nanoplatform via improvement of IRN efficiency could be applied for inducing synergistic toxicity against CC.

The negative impact of vitamin D on antipsychotic drug exposure may counteract its potential benefits in schizophrenia.

Patients with schizophrenia frequently show insufficient vitamin D levels, which are associated with somatic comorbidity and may contribute to psychopathology. For many reasons, vitamin D supplementation may be indicated for this patient cohort. However, there is growing evidence for a vitamin D-mediated increase of drug metabolism by induction of cytochrome P450 (CYP) 3A4. Hence, this study aimed to assess vitamin D's impact on both antipsychotic drug concentrations and psychopathology in a non-interventional manner. Totals of 107 serum concentrations of different antipsychotic drugs (amisulpride, aripiprazole, clozapine, olanzapine, quetiapine and risperidone), 80 serum concentrations of vitamin D and psychopathological assessments were obtained from 80 patients with schizophrenia. The impact of Vitamin D on antipsychotic drug concentrations and symptomatology was assessed using a generalized linear model, path and correlation analyses. We observed a negative relationship between vitamin D and dose-adjusted antipsychotic drug concentrations, which was particularly pronounced for drugs which are predominantly metabolized via CYP3A4 (i.e., aripiprazole and quetiapine). A path analysis suggested a relieving effect of vitamin D on symptomatology which was, however, counteracted by its negative impact on antipsychotic drug levels. Finally, patients with vitamin D levels above the median exhibited a significantly higher proportion of therapeutically insufficient dose-normalized drug concentrations of aripiprazole and quetiapine. Despite vitamin D's potential benefits on physical and mental health, clinicians should be aware of its negative impact on blood concentrations of antipsychotics metabolized by CYP3A4 in patients with schizophrenia. Therefore, when considering its supplementation, therapeutic drug monitoring should be applied to guide dose adjustment.

Prediction of Insufficient Beta-Lactam Concentrations in Extracorporeal Membranous Oxygenation Patients.

Background: The aim of this study was to identify predictors of insufficient beta-lactam concentrations in patients undergoing extracorporeal membrane oxygenation (ECMO). Methods: Retrospective analysis of all patients receiving ECMO support and treated with ceftazidime or cefepime (CEF), piperacillin/tazobactam (TZP), or meropenem (MEM). Trough drug concentrations (Cmin) were measured before the subsequent dose, according to the decision of the attending physician. Insufficient drug concentrations were identified if Cmin was below the clinical breakpoint of Pseudomonas aeruginosa. Results: A total of 222 Cmin (CEF, n = 41; TZP, n = 85; MEM, n = 96) from 110 patients were included; insufficient concentrations were observed in 26 (12%) antibiotic assessments; 21 (81%) of those occurred during MEM therapy. Insufficient Cmin were associated with a shorter time from initiation of antibiotics to measurement, a lower single dose of antibiotic, a higher creatinine clearance (CrCL), lower sequential organ failure assessment (SOFA) scores, and less use of continuous renal replacement therapy (CRRT) when compared to others. Conclusions: Insufficient broad-spectrum beta-lactam concentrations were observed in 12% of drug measurement during ECMO therapy. Higher than recommended drug regimens could be considered in the very early phase of therapy and in those patients with augmented renal clearance and with less severe organ dysfunction.

Aerosolized antibiotics in the treatment of hospital-acquired pneumonia/ventilator-associated pneumonia

Aerosolized antibiotics are being increasingly used to treat respiratory infections, especially those caused by drug-resistant pathogens. Their use in the treatment of hospital-acquired pneumonia and ventilator-associated pneumonia in critically ill patients is especially significant. They are also used as an efficient alternative to overcome the issues caused by systemic administration of antibiotics, including the occurrence of drug-resistant strains, drug toxicity, and insufficient drug concentration at the target site. However, the rationale for the use of aerosolized antibiotics is limited owing to their insufficient efficacy and the potential for underestimated risks of developing side effects. Despite the lack of availability of high-quality evidence, the use of aerosolized antibiotics is considered as an attractive alternative treatment approach, especially in patients with multidrug-resistant pathogens. In this review, we have discussed the effectiveness and side effects of aerosolized antibiotics as well as the latest advancements in this field and usage in the Republic of Korea.