A phase 1/2 study of NS-87/CPX-351 (cytarabine and daunorubicin liposome) in Japanese patients with high-risk acute myeloid leukemia.

OBJECTIVES: NS-87/CPX-351 is a dual-drug liposomal encapsulation of cytarabine and daunorubicin. NS-87/CPX-351 exerts antileukemic action by maintaining a synergistic molar ratio of cytarabine to daunorubicin of 5:1 within the liposome while in circulation. Patients with high-risk acute myeloid leukemia (AML), which includes therapy-related AML and AML with myelodysplasia-related changes (AML-MRC), have poorer outcomes than those with other AML. METHODOLOGY: This open-label phase 1/2 (P1/2) study was conducted in 47 Japanese patients aged 60-75 years with newly diagnosed high-risk AML to evaluate the pharmacokinetics, safety, and efficacy of NS-87/CPX-351. RESULTS: In the 6 patients enrolled in the P1 portion, no dose-limiting toxicities (DLTs) were reported, and 100 units/m2 during the induction cycle was found to be acceptable. Cytarabine and daunorubicin had a long half-life in the terminal phase (32.8 and 28.7 h, respectively). In the 35 patients enrolled in the P2 portion, composite complete remission (CRc; defined as complete remission [CR] or CR with incomplete hematologic recovery [CRi]) was achieved in 60.0% (90% CI: 44.7-74.0) of the patients. Adverse events due to NS-87/CPX-351 were well tolerated. OUTCOMES: NS-87/CPX-351 can be considered as a frontline treatment option for Japanese patients with high-risk AML.

Liposomal co-delivery of toll-like receptors 3 and 7 agonists induce a hot triple-negative breast cancer immune environment.

Triple-negative breast cancer (TNBC) is highly aggressive and has no standard treatment. Although being considered as an alternative to conventional treatments for TNBC, immunotherapy has to deal with many challenges that hinder its efficacy, particularly the poor immunogenic condition of the tumor microenvironment (TME). Herein, we designed a liposomal nanoparticle (LN) platform that delivers simultaneously toll-like receptor 7 (imiquimod, IQ) and toll-like receptor 3 (poly(I:C), IC) agonists to take advantage of the different toll-like receptor (TLR) signaling pathways, which enhances the condition of TME from a "cold" to a "hot" immunogenic state. The optimized IQ/IC-loaded LN (IQ/IC-LN) was effectively internalized by cancer cells, macrophages, and dendritic cells, followed by the release of the delivered drugs and subsequent stimulation of the TLR3 and TLR7 signaling pathways. This stimulation encouraged the secretion of type I interferon (IFN-α, IFN-ß) and CXCLl0, a T-cell and antigen-presenting cells (APCs) recruitment chemokine, from both cancer cells and macrophages and polarized macrophages to the M1 subtype in in vitro studies. Notably, systemic administration of IQ/IC-LN allowed for the high accumulation of drug content in the tumor, followed by the effective uptake by immune cells in the TME. IQ/IC-LN treatment comprehensively enhanced the immunogenic condition in the TME, which robustly inhibited tumor growth in tumor-bearing mice. Furthermore, synergistic antitumor efficacy was obtained when the IQ/IC-LN-induced immunogenic state in TME was combined with anti-PD1 antibody therapy. Thus, our results suggest the potential of combining 2 TLR agonists to reform the TME from a "cold" to a "hot" state, supporting the therapeutic efficacy of immune checkpoint inhibitors.

Subconjunctival Sirolimus-Loaded Liposomes for the Treatment of Moderate-to-Severe Dry Eye Disease.

Purpose: To determine the effectiveness of subconjunctival application of a novel sirolimus liposomal formulation for the treatment of dry eye. Methods: A randomized, triple-blind, Phase II clinical trial. Thirty-eight eyes of 19 patients were included. Nine patients (18 eyes) assigned to the sham group (Sham) and 10 patients (20 eyes) to sirolimus-loaded liposomes group (Sirolimus). The treatment group received three doses of subconjunctival liposome-encapsulated sirolimus and the sham group received three doses of liposomal suspension without sirolimus. Subjective (Ocular Surface Disease Index, OSDI) and measured (corrected distance visual acuity, conjunctival hyperemia, tear osmolarity, Schirmer's test, corneal/conjunctival staining and matrix metalloproteinase-9) variables were measured. Results: Sirolimus-entrapped liposomes-treated group OSDI scores changed from 62.19 (± 6.07) to 37.8 (± 17.81) (p=0.0024), and conjunctival hyperemia from 2.0 (± 0.68) to 0.83 (± 0.61) (p<0.0001); Sham group with OSDI scores from 60.02 (± 14.2) to 36.02 (± 20.70) (p=0.01), and conjunctival hyperemia from 1.33 (± 0.68) to 0.94 (± 0.87) (p=0.048). All the other evaluated outcomes only showed significant differences in the sirolimus group: corneal/conjunctival staining score (p=0.0015), lipid layer interferometry (p=0.006), and inferior meibomian gland dropout (p=0.038). No local or systemic adverse effects regarding the medication itself were reported, and the administration route was well accepted. Conclusion: Our findings suggest that sub-conjunctival sirolimus-loaded liposomes are effective in reducing both signs and symptoms of dry eye in patients with poorly controlled moderate-to-severe DED, while avoiding other topical administration adverse effects. Further investigation with a larger sample size is required to determine long-term effects.

A systemically administered detoxified TLR4 agonist displays potent antitumor activity and an acceptable tolerance profile in preclinical models.

Bacterial lipopolysaccharides (LPS) are potent innate immunostimulants targeting the Toll-like receptor 4 (TLR4), an attractive and validated target for immunostimulation in cancer therapy. Although LPS possess anti-tumor activity, toxicity issues prevent their systemic administration at effective doses in humans. We first demonstrated that LPS formulated in liposomes preserved a potent antitumor activity per se upon systemic administration in syngeneic models, and significantly enhance the antitumor activity of the anti-CD20 antibody rituximab in mice xenografted with the human RL lymphoma model. Liposomal encapsulation also allowed a 2-fold reduction in the induction of pro-inflammatory cytokines by LPS. Mice receiving an intravenous administration demonstrated a significant increase of neutrophils, monocytes and macrophages at the tumor site as well as an increase of macrophages in spleen. Further, we chemically detoxified LPS to obtain MP-LPS that was associated with a 200-fold decrease in the induction of proinflammatory cytokines. When encapsulated in a clinically approved liposomal formulation, toxicity, notably pyrogenicity (10-fold), was limited while the antitumor activity and immunoadjuvant effect were maintained. This improved tolerance profile of liposomal MP-LPS was associated with the preferential activation of the TLR4-TRIF pathway. Finally, in vitro studies demonstrated that stimulation with encapsulated MP-LPS reversed the polarization of M2 macrophages towards an M1 phenotype, and a phase 1 trial in healthy dogs validated its tolerance upon systemic administration up to very high doses (10µg/kg). Altogether, our results demonstrate the strong therapeutic potential of MPLPS formulated in liposomes as a systemically active anticancer agent, supporting its evaluation in patients with cancer.

Selective COX-2 Inhibitor Etoricoxib's Liposomal Formulation Attenuates M2 Polarization of TAMs and Enhances its Anti-metastatic Potential.

INTRODUCTION: COX-2 inhibition in pro-tumoral M2 polarization of Tumor-Associated Macrophages (TAMs) underscore the improved prognosis and response to cancer therapy. Thus, etoricoxib, a COX-2 inhibiting NSAID drug is highly effective against tumorigenesis, but its compromised solubility and associated hepatotoxicity, and cardiotoxicity limit its clinical translation. OBJECTIVE: In view of the consequences, the proposed study entails the development of a liposomal formulation for etoricoxib and evaluates its anticancer potential. METHODS AND RESULT: Etoricoxib loaded liposome was prepared by thin layer hydration method and characterized as a nearly monodisperse system with particle size (91.64 nm), zeta potential (-44.5 mV), drug loading (17.22%), and entrapment efficiency (94.76%). The developed formulation was administered subcutaneously into the orthotopic 4T1/Balb/c mice model. Its treatment significantly reduced tumor size and skewed M2 polarization of TAMs to a greater extent against free etoricoxib. Furthermore, Tumor tissues analyzed through immunoblotting study confirmed the reduction in Akt phosphorylation at Thr308 residue and pro-tumoral VEGF, MMP-9, and MMP-2 proteins; Moreover, histology studies and microCT analysis of bones revealed the enhanced anti-metastatic potential of etoricoxib delivered through developed formulation against free etoricoxib. CONCLUSION: As an epilogue, the developed formulation efficiently delivers poorly soluble etoricoxib, enhances its therapeutic potential as an anti-tumor and anti-metastatic agent, and directs explorative research for clinical translation.

A Dual Adjuvant System for Intranasal Boosting of Local and Systemic Immunity for Influenza Vaccination.

Systemically vaccinated individuals against COVID-19 and influenza may continue to support viral replication and shedding in the upper airways, contributing to the spread of infections. Thus, a vaccine regimen that enhances mucosal immunity in the respiratory mucosa is needed to prevent a pandemic. Intranasal/pulmonary (IN) vaccines can promote mucosal immunity by promoting IgA secretion at the infection site. Here, we demonstrate that an intramuscular (IM) priming-IN boosting regimen with an inactivated influenza A virus adjuvanted with the liposomal dual TLR4/7 adjuvant (Fos47) enhances systemic and local/mucosal immunity. The IN boosting with Fos47 (IN-Fos47) enhanced antigen-specific IgA secretion in the upper and lower respiratory tracts compared to the IM boosting with Fos47 (IM-Fos47). The secreted IgA induced by IN-Fos47 was also cross-reactive to multiple influenza virus strains. Antigen-specific tissue-resident memory T cells in the lung were increased after IN boosting with Fos47, indicating that IN-Fos47 established tissue-resident T cells. Furthermore, IN-Fos47 induced systemic cross-reactive IgG antibody titers comparable to those of IM-Fos47. Neither local nor systemic reactogenicity or adverse effects were observed after IN delivery of Fos47. Collectively, these results indicate that the IM/IN regimen with Fos47 is safe and provides both local and systemic anti-influenza immune responses.

First-in-human assessment of safety and immunogenicity of low and high doses of Plasmodium falciparum malaria protein 013 (FMP013) administered intramuscularly with ALFQ adjuvant in healthy malaria-naïve adults.

The global burden of malaria remains substantial. Circumsporozoite protein (CSP) has been demonstrated to be an effective target antigen, however, improvements that offer more efficacious and more durable protection are still needed. In support of research and development of next-generation malaria vaccines, Walter Reed Army Institute of Research (WRAIR) has developed a CSP-based antigen (FMP013) and a novel adjuvant ALFQ (Army Liposome Formulation containing QS-21). We present a single center, open-label, dose-escalation Phase 1 clinical trial to evaluate the safety and immunogenicity of the FMP013/ALFQ malaria vaccine candidate. In this first-in-human evaluation of both the antigen and adjuvant, we enrolled ten subjects; five received 20 µg FMP013 / 0.5 mL ALFQ (Low dose group), and five received 40 µg FMP013 / 1.0 mL ALFQ (High dose group) on study days 1, 29, and 57. Adverse events and immune responses were assessed during the study period. The clinical safety profile was acceptable and there were no serious adverse events. Both groups exhibited robust humoral and cellular immunological responses, and compared favorably with historical responses reported for RTS,S/AS01. Based on a lower reactogenicity profile, the 20 µg FMP013 / 0.5 mL ALFQ (Low dose) was selected for follow-on efficacy testing by controlled human malaria infection (CHMI) with a separate cohort. Trial Registration:Clinicaltrials.gov Identifier NCT04268420 (Registered February 13, 2020).

Amphotericin B: A drug of choice for Visceral Leishmaniasis.

Visceral leishmaniasis or Kala-azar is a vector-borne disease caused by an intracellular parasite of the genus leishmania. In India, Amphotericin B (AmB) is a first-line medication for treating leishmaniasis. After a large-scale resistance to pentavalent antimony therapy developed in Bihar state, it was rediscovered as an effective treatment for Leishmania donovani infection. AmB which binds to the ergosterol of protozoan cells causes a change in membrane integrity resulting in ions leakage, and ultimately leading to cell death. The treatment effect of liposomal AmB can be seen more quickly than deoxycholate AmB because, it has some toxic effects, but liposomal AmB is significantly less toxic. Evidence from studies suggested that ABLC (Abelcet) and ABCD (Amphotec) are as effective as l-AmB but Liposomal form (Ambisome) is a more widely accepted treatment option than conventional ones. Nevertheless, the world needs some way more efficient antileishmanial drugs that are less toxic and less expensive for people living with parasitic infections caused by Leishmania. So, academics, researchers, and sponsors need to focus on finding such drugs. This review provides a summary of the chemical, pharmacokinetic, drug-target interactions, stability, dose efficacy, and many other characteristics of the AmB and their various formulations. We have also highlighted the clinically significant aspects of PKDL and VL co-infection with HIV/TB.

Characterization of a Mesoporous Silica Nanoparticle Formulation Loaded with Mitomycin C Lipidic Prodrug (MLP) and In Vitro Comparison with a Clinical-Stage Liposomal Formulation of MLP.

Nanomedicines have revolutionized the treatment of certain types of cancer, as is the case of doxil, liposomal formulation with doxorubicin encapsulated, in the treatment of certain types of ovarian cancer, AIDS-related Kaposi sarcoma, and multiple myeloma. These nanomedicines can improve the performance of conventional chemotherapeutic treatments, with fewer side effects and better efficiency against cancer. Although liposomes have been used in some formulations, different nanocarriers with better features in terms of stability and adsorption capabilities are being explored. Among the available nanoparticles in the field, mesoporous silica nanoparticles (MSNP) have attracted great attention as drug delivery platforms for the treatment of different diseases. Here, a novel formulation based on MSNP loaded with a potent antitumor prodrug that works in vitro as well as in a clinically evaluated liposomal formulation has been developed. This novel formulation shows excellent prodrug encapsulation efficiency and effective release of the anticancer drug only under certain stimuli typical of tumor environments. This behavior is of capital importance for translating this nanocarrier to the clinic in the near future.

Polyene Antibiotics Physical Chemistry and Their Effect on Lipid Membranes; Impacting Biological Processes and Medical Applications.

This review examined a collection of studies regarding the molecular properties of some polyene antibiotic molecules as well as their properties in solution and in particular environmental conditions. We also looked into the proposed mechanism of action of polyenes, where membrane properties play a crucial role. Given the interest in polyene antibiotics as therapeutic agents, we looked into alternative ways of reducing their collateral toxicity, including semi-synthesis of derivatives and new formulations. We follow with studies on the role of membrane structure and, finally, recent developments regarding the most important clinical applications of these compounds.

A SARS-CoV-2 Spike Ferritin Nanoparticle Vaccine Is Protective and Promotes a Strong Immunological Response in the Cynomolgus Macaque Coronavirus Disease 2019 (COVID-19) Model.

The COVID-19 pandemic has had a staggering impact on social, economic, and public health systems worldwide. Vaccine development and mobilization against SARS-CoV-2 (the etiologic agent of COVID-19) has been rapid. However, novel strategies are still necessary to slow the pandemic, and this includes new approaches to vaccine development and/or delivery that will improve vaccination compliance and demonstrate efficacy against emerging variants. Here, we report on the immunogenicity and efficacy of a SARS-CoV-2 vaccine comprising stabilized, pre-fusion spike protein trimers displayed on a ferritin nanoparticle (SpFN) adjuvanted with either conventional aluminum hydroxide or the Army Liposomal Formulation QS-21 (ALFQ) in a cynomolgus macaque COVID-19 model. Vaccination resulted in robust cell-mediated and humoral responses and a significant reduction in lung lesions following SARS-CoV-2 infection. The strength of the immune response suggests that dose sparing through reduced or single dosing in primates may be possible with this vaccine. Overall, the data support further evaluation of SpFN as a SARS-CoV-2 protein-based vaccine candidate with attention to fractional dosing and schedule optimization.

Impact of critical process parameters and critical material attributes on the critical quality attributes of liposomal formulations prepared using continuous processing.

Liposomes were one of the earliest drug delivery vehicles used for anti-cancer therapeutics and similarly, lipid-based nanoparticles have been used for abundance of applications as gene therapies. The methods to produce these particles have remained relatively unchanged until the recent emergence of continuous manufacturing. Continuous processing enables accelerated development of nanoparticle formulations while providing a scalable manufacturing solution. For this work a continuous processing platform for the production of lipid and polymeric-based nanoparticle formulations has been developed at the University of Connecticut. This research focuses on the formation of liposomes encompassing multiple design of experiments (DoEs) to identify functional relationships between critical process parameters (CPPs), critical material attributes (CMAs), and critical quality attributes (CQAs) for liposomal formulations produced using this continuous processing platform. Liposomes of various sizes and of low polydispersity index (PDI) were produced with different material attributes under various processing conditions. In general, lower mole percentages of cholesterol produced larger particles whereas the mole percent of phosphatidylglycerol did not seem to have a s impact on the size of the liposomes that were produced. The results showed that similarly sized liposomes could be produced with different processing conditions allowing for the flexibility to operate in regions most suitable for formulation components that may be sensitive to certain processing conditions. For example, if the target size of a formulation is 100 nm but the active pharmaceutical ingredient is sensitive to temperature, then the formulation can be manufactured at high (55 °C) or low (30 °C) depending on its characteristics. Additionally, the relationships between CMAs and CPPs were different from conventional liposomal manufacturing methods, allowing for more flexibility when using a continuous processing system. Models that can effectively predict the hydrodynamic diameter of monodispersed liposomes produced using continuous processing were developed. The models developed from the DoEs in this study may be useful for accelerated development of new lipid formulations as well as facilitate the translation from traditional manufacturing methods to continuous manufacturing for products already on the market.

New potential antiproliferative monophosphoester 2-aminoethyl dihydrogen phosphate in K-562 and K-562 MDR+ leukemia cells.

The main obstacle in the treatment of cancer patients has been resistance to multiple drugs, leading to the need to develop molecules with a higher specificity target. The liposomal formulation DODAC/2-AEH2P has antitumor potential, inducing apoptosis in several tumor types. Human chronic myeloid leukemia K-562 and K-562 Lucena (MDR+) cells were treated with the DODAC carrier and the liposomal formulation 2-AEH2P. Viability, cell cycle phases, apoptosis, marker expression and mitochondrial potential were analyzed. Significant reduction in viability was observed for all treatments. Changes in the distribution of the cell cycle phases and expression of markers involved in the apoptosis pathways were observed. Reduction of the mitochondrial electrical potential mediated by Bcl-2, being regulated by the reduction of the MTCH2 protein linked to the progression of myeloid leukemia and an increase in the pro-apoptotic proteins Bad and Bax, dependent on p53. This study demonstrated a significant therapeutic potential through apoptotic effects in leukemic cells, regardless of the molecular resistance profile (MDR+).

Formulations Based on Drug Loaded Aptamer-Conjugated Liposomes as a Viable Strategy for the Topical Treatment of Basal Cell Carcinoma-In Vitro Tests.

Topical liposomal drug formulations containing AS1411-aptamer conjugated liposomes were designed to deliver in a sustained way the 5-fluorouracil to the tumor site but also to increase the compliance of patients with basal cell carcinoma. The 5-fluorouracil penetrability efficiency through the Strat-M membrane and the skin irritation potential of the obtained topical liposomal formulations were evaluated in vitro and the Korsmeyer Peppas equation was considered as the most appropriate to model the drug release. Additionally, the efficiency of cytostatic activity for targeted antitumor therapy and the hemolytic capacity were performed in vitro. The obtained results showed that the optimal liposomal formulation is a crosslinked gel based on sodium alginate and hyaluronic acid containing AS1411-aptamer conjugated liposomes loaded with 5-fluorouracil, which appeared to have favorable biosafety effects and may be used as a new therapeutic approach for the topical treatment of basal cell carcinoma.

New potential antiproliferative monophosphoester 2-aminoethyl dihydrogen phosphate in K-562 and K-562 MDR+ leukemia cells

The main obstacle in the treatment of cancer patients has been resistance to multiple drugs, leading to the need to develop molecules with a higher specificity target. The liposomal formulation DODAC/2-AEH2P has antitumor potential, inducing apoptosis in several tumor types. Human chronic myeloid leukemia K-562 and K-562 Lucena (MDR+) cells were treated with the DODAC carrier and the liposomal formulation 2-AEH2P. Viability, cell cycle phases, apoptosis, marker expression and mitochondrial potential were analyzed. Significant reduction in viability was observed for all treatments. Changes in the distribution of the cell cycle phases and expression of markers involved in the apoptosis pathways were observed. Reduction of the mitochondrial electrical potential mediated by Bcl-2, being regulated by the reduction of the MTCH2 protein linked to the progression of myeloid leukemia and an increase in the pro-apoptotic proteins Bad and Bax, dependent on p53. This study demonstrated a significant therapeutic potential through apoptotic effects in leukemic cells, regardless of the molecular resistance profile (MDR+).

Reducing Doxorubicin resistance in breast cancer by liposomal FOXM1 aptamer: In vitro and in vivo.

AIMS: Drug resistance is one of the main obstacles in cancer chemotherapy. The forkhead box M1 (FOXM1) is a transcription factor and its overexpression in breast cancer is related to resistance to chemotherapy. In this study, we prepare liposomal FOXM1 aptamer (Lip-FOXM1apt) and evaluate its effects on Doxorubicin (Dox) resistance in vitro and in vivo. MAIN METHODS: MTT assay, cell association, cellular uptake, Annexin V-FITC/PI dual staining assay were investigated in MDA-MB-231, MCF-7, 4T1. In vivo studies were performed in 4T1 tumor-bearing BALB/c mice. KEY FINDINGS: We found that the combination therapy of Dox and Lip-FOXM1apt significantly increases both Dox cytotoxicity on cancer cells as well as Dox-induced apoptosis. Administering Lip-FOXM1apt remarkably improved the anti-tumor efficacy of Dox in mice model that was strikingly more effective than Dox monotherapy. SIGNIFICANCE: Taken together, this study provides a new strategy to overcome Dox resistance and merits further investigation.

Formulation, Pharmacological Evaluation, and Efficacy Studies of Occidiofungin, a Novel Antifungal.

Occidiofungin is a nonribosomally synthesized cyclic lipopeptide that possesses broad-spectrum antifungal properties at submicromolar concentrations. This report explores multiple routes of administration and formulations of occidiofungin, as well as its toxicity in mice. Further, infection studies were performed in mice to assess the application of occidiofungin for treating systemic and intravaginal yeast infections. Formulations for intravenous and intravaginal administration of occidiofungin were prepared. Pharmacokinetic analyses were performed in a murine model, and a liquid chromatography-mass spectrometry (LC-MS) method was developed and used to quantify occidiofungin in mouse plasma samples. Toxicological and histopathological analyses of two repeat-dose studies using occidiofungin were performed. In these animal models, following intravenous administration, a liposomal formulation of occidiofungin improved the half-life and peak plasma drug concentration over that with a liposome-free formulation. Two long-term repeat-dosing toxicity studies of occidiofungin indicated the absence of toxicity in organ tissues. Murine models of a systemic yeast infection and a vulvovaginal yeast infection were performed. The findings of the systemic infection study revealed limitations in the use of occidiofungin that may be alleviated with the development of novel structural analogs or with further formulation studies. The gel formulation of occidiofungin demonstrated improved efficacy over that of the commercial product Monistat 3 in a vulvovaginal candidiasis study. This report outlines the optimal routes of administration of occidiofungin and demonstrates minimal toxicity following chronic exposure. Further, the results of these studies provide a clear indication for the use of occidiofungin for the treatment of recurrent vulvovaginal candidiasis (RVVC), which is a serious and clinically relevant issue.

Development and In Vivo Application of a Water-Soluble Anticancer Copper Ionophore System Using a Temperature-Sensitive Liposome Formulation.

Liposomes containing copper and the copper ionophore neocuproine were prepared and characterized for in vitro and in vivo anticancer activity. Thermosensitive PEGylated liposomes were prepared with different molar ratios of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) and hydrogenated soybean phosphatidylcholine (HSPC) in the presence of copper(II) ions. Optimal, temperature dependent drug release was obtained at 70:30 DPPC to HSPC weight ratio. Neocuproine (applied at 0.2 mol to 1 mol phospholipid) was encapsulated through a pH gradient while using unbuffered solution at pH 4.5 inside the liposomes, and 100 mM HEPES buffer pH 7.8 outside the liposomes. Copper ions were present in excess, yielding 0.5 mM copper-(neocuproine)2 complex and 0.5 mM free copper. Pre-heating to 45 °C increased the toxicity of the heat-sensitive liposomes in short-term in vitro experiments, whereas at 72 h all investigated liposomes exhibited similar in vitro toxicity to the copper(II)-neocuproine complex (1:1 ratio). Thermosensitive liposomes were found to be more effective in reducing tumor growth in BALB/c mice engrafted with C26 cancer cells, regardless of the mild hyperthermic treatment. Copper uptake of the tumor was verified by PET/CT imaging following treatment with [64Cu]Cu-neocuproine liposomes. Taken together, our results demonstrate the feasibility of targeting a copper nanotoxin that was encapsulated in thermosensitive liposomes containing an excess of copper.

Dog-specific hemorrhagic changes induced by liposomal formulations, in the liver and the gallbladder.

Although several liposomal drugs, including liposomal doxorubicin, have been approved, the etiology of the pathological responses caused by their physicochemical properties remains unknown. Herein, we investigated the pathological changes in the liver and the gallbladder of dogs following a single injection of liposomal doxorubicin (1 or 2.5 mg/kg) or an empty liposomal formulation (i.e., liposomal formulation without doxorubicin, ca. 21 mg/kg as lipid content). Injection of liposomal doxorubicin or the empty liposomal formulation induced hemorrhagic changes in the liver and the gallbladder. These changes were accompanied by minimal cellular infiltration with no obvious changes in the blood vessels. As there were no differences in the incidence and severity of hemorrhage between the groups administered comparable amounts of total lipid, the physicochemical properties of the liposomal formulation rather than an active pharmacological ingredient, doxorubicin, were associated with the hemorrhagic changes. Furthermore, decreased cytoplasmic granules with low electron density in mast cells beneath the endothelium of the hepatic vein were observed in the liver of dogs treated with liposomal doxorubicin or empty liposomal formulation. Injection of compound 48/80, a histamine releaser induced comparable hemorrhage in dogs, implying that hemorrhage caused by injection of liposomal doxorubicin or the empty liposomal formulation could be attributed to the histamine released from mast cells. The absence of similar hemorrhagic lesions in other species commonly used in toxicology studies (i.e., rats and monkeys), as well as humans, is due to the lack of mast cells beneath the endothelium of the hepatic vein in these species.

Evaluation of the in vivo genotoxicity of liposomal formulation for delivering anticancer estrogenic derivative (ESC8) in a mouse model.

The genotoxic potential of glucocorticoid receptor (GR)-targeted liposomal formulations of the anticancer drug molecule ESC8 was studied in vivo. A methodical literature review discovered no previous studies on the genotoxicity of ESC8. Genotoxicity was assessed in both male and female mice by various assay systems, such as comet assay, chromosomal aberrations and micronuclei assay, which detect different abnormalities. Eleven groups of male mice and eleven groups of female mice, containing six animals per group, were used in the present study: group I served as vehicle control; group II received the positive control (cyclophosphamide 40 mg/kg; CYP); and animals in group III to XI received free drug (ESC8), DX liposome and drug-associated DX liposomal formulation (DXE), respectively, dissolved in 5% solution of glucose at a drug-dose of 1.83, 3.67 and 7.34 mg/kg, respectively. Same drug treatments were followed for the female mice groups. The obtained data revealed the safety of DXE, which did not show substantial genotoxic effects at different dose levels. In contrast, the positive control, CYP, exhibited highly substantial irregular cytogenetic variations in comparison with the control group in different assays.