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1.
Mol Pharm ; 20(12): 6213-6225, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37917742

RESUMO

Lenacapavir (LEN) is a picomolar first-in-class capsid inhibitor of human immunodeficiency virus type 1 (HIV-1) with a multistage mechanism of action and no known cross resistance to other existing antiretroviral (ARV) drug classes. LEN exhibits a low aqueous solubility and exceptionally low systemic clearance following intravenous (IV) administration in nonclinical species and humans. LEN formulated in an aqueous suspension or a PEG/water solution formulation showed sustained plasma exposure levels with no unintended rapid drug release following subcutaneous (SC) administration to rats and dogs. A high total fraction dose release was observed with both formulations. The long-acting pharmacokinetics (PK) were recapitulated in humans following SC administration of both formulations. The SC PK profiles displayed two-phase absorption kinetics in both animals and humans with an initial fast-release absorption phase, followed by a slow-release absorption phase. Noncompartmental and compartmental analyses informed the LEN systemic input rate from the SC depot and exit rate from the body. Modeling-enabled deconvolution of the input rates from two processes: absorption of the soluble fraction (minor) from a direct fast-release process leading to the early PK phase and absorption of the precipitated fraction (major) from an indirect slow-release process leading to the later PK phase. LEN SC PK showed flip-flop kinetics due to the input rate being substantially slower than the systemic exit rate. LEN input rates via the slow-release process in humans were slower than those in both rats and dogs. Overall, the combination of high potency, exceptional stability, and optimal release rate from the injection depot make LEN well suited for a parenteral long-acting formulation that can be administered once up to every 6 months in humans for the prevention and treatment of HIV-1.


Assuntos
Fármacos Anti-HIV , HIV-1 , Humanos , Ratos , Animais , Cães , Antirretrovirais , Capsídeo , Fármacos Anti-HIV/farmacologia , Proteínas do Capsídeo
2.
EBioMedicine ; 95: 104764, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37625266

RESUMO

BACKGROUND: Long-acting subcutaneous lenacapavir (LEN), a first-in-class HIV capsid inhibitor approved by the US FDA for the treatment of multidrug-resistant HIV-1 with twice yearly dosing, is under investigation for HIV-1 pre-exposure prophylaxis (PrEP). We previously derived a simian-tropic HIV-1 clone (stHIV-A19) that encodes an HIV-1 capsid and replicates to high titres in pigtail macaques (PTM), resulting in a nonhuman primate model well-suited for evaluating LEN PrEP in vivo. METHODS: Lenacapavir potency against stHIV-A19 in PTM peripheral blood mononuclear cells in vitro was determined and subcutaneous LEN pharmacokinetics were evaluated in naïve PTMs in vivo. To evaluate the protective efficacy of LEN PrEP, naïve PTMs received either a single subcutaneous injection of LEN (25 mg/kg, N = 3) or vehicle (N = 4) 30 days before a high-dose intravenous challenge with stHIV-A19, or 7 daily subcutaneous injections of a 3-drug control PrEP regimen starting 3 days before stHIV-A19 challenge (N = 3). FINDINGS: In vitro, LEN showed potent antiviral activity against stHIV-A19, comparable to its potency against HIV-1. In vivo, subcutaneous LEN displayed sustained plasma drug exposures in PTMs. Following stHIV-A19 challenge, while all vehicle control animals became productively infected, all LEN and 3-drug control PrEP animals were protected from infection. INTERPRETATION: These findings highlight the utility of the stHIV-A19/PTM model and support the clinical development of long-acting LEN for PrEP in humans. FUNDING: Gilead Sciences as part of a Cooperative Research and Development Agreement between Gilead Sciences and Frederick National Lab; federal funds from the National Cancer Institute, National Institutes of Health, under Contract No. 75N91019D00024/HHSN261201500003I; NIH grant R01AI078788.


Assuntos
Fármacos Anti-HIV , Soropositividade para HIV , HIV-1 , Estados Unidos , Animais , Humanos , Macaca , Leucócitos Mononucleares , Administração Intravenosa , Proteínas do Capsídeo
3.
Arthritis Res Ther ; 25(1): 57, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041650

RESUMO

BACKGROUND: We sought to discover serum biomarkers of ankylosing spondylitis (AS) for diagnosis and monitoring disease activity. METHODS: We studied biologic-treatment-naïve AS and healthy control (HC) patients' sera. Eighty samples matched by age, gender, and race (1:1:1 ratio) for AS patients with active disease, inactive disease, and HC were analyzed with SOMAscan™, an aptamer-based discovery platform. T-tests tests were performed for high/low-disease activity AS patients versus HCs (diagnosis) and high versus low disease activity (Monitoring) in a 2:1 and 1:1 ratio, respectively, to identify differentially expressed proteins (DEPs). We used the Cytoscape Molecular Complex Detection (MCODE) plugin to find clusters in protein-protein interaction networks and Ingenuity Pathway Analysis (IPA) for upstream regulators. Lasso regression analysis was performed for diagnosis. RESULTS: Of the 1317 proteins detected in our diagnosis and monitoring analyses, 367 and 167 (317 and 59, FDR-corrected q < .05) DEPs, respectively, were detected. MCODE identified complement, IL-10 signaling, and immune/interleukin signaling as the top 3 diagnosis PPI clusters. Complement, extracellular matrix organization/proteoglycans, and MAPK/RAS signaling were the top 3 monitoring PPI clusters. IPA showed interleukin 23/17 (interleukin 22, interleukin 23A), TNF (TNF receptor-associated factor 3), cGAS-STING (cyclic GMP-AMP synthase, Stimulator of Interferon Gene 1), and Jak/Stat (Signal transducer and activator of transcription 1), signaling in predicted upstream regulators. Lasso regression identified a Diagnostic 13-protein model predictive of AS. This model had a sensitivity of 0.75, specificity of 0.90, a kappa of 0.59, and overall accuracy of 0.80 (95% CI: 0.61-0.92). The AS vs HC ROC curve was 0.79 (95% CI: 0.61-0.96). CONCLUSION: We identified multiple candidate AS diagnostic and disease activity monitoring serum biomarkers using a comprehensive proteomic screen. Enrichment analysis identified key pathways in AS diagnosis and monitoring. Lasso regression identified a multi-protein panel with modest predictive ability.


Assuntos
Proteômica , Espondilite Anquilosante , Humanos , Biomarcadores/sangue , Proteoglicanas/metabolismo , Curva ROC , Espondilite Anquilosante/sangue , Espondilite Anquilosante/diagnóstico
4.
Nature ; 601(7894): 612-616, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34875675

RESUMO

Because no currently available vaccine can prevent HIV infection, pre-exposure prophylaxis (PrEP) with antiretrovirals (ARVs) is an important tool for combating the HIV pandemic1,2. Long-acting ARVs promise to build on the success of current PrEP strategies, which must be taken daily, by reducing the frequency of administration3. GS-CA1 is a small-molecule HIV capsid inhibitor with picomolar antiviral potency against a broad array of HIV strains, including variants resistant to existing ARVs, and has shown long-acting therapeutic potential in a mouse model of HIV infection4. Here we show that a single subcutaneous administration of GS-CA1 provides long-term protection against repeated rectal simian-human immunodeficiency virus (SHIV) challenges in rhesus macaques. Whereas all control animals became infected after 15 weekly challenges, a single 300 mg kg-1 dose of GS-CA1 provided per-exposure infection risk reduction of 97% for 24 weeks. Pharmacokinetic analysis showed a correlation between GS-CA1 plasma concentration and protection from SHIV challenges. GS-CA1 levels greater than twice the rhesus plasma protein-adjusted 95% effective concentration conferred 100% protection in this model. These proof-of-concept data support the development of capsid inhibitors as a novel long-acting PrEP strategy in humans.


Assuntos
Antirretrovirais , Proteínas do Capsídeo , Capsídeo , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , Antirretrovirais/farmacologia , Capsídeo/efeitos dos fármacos , Proteínas do Capsídeo/antagonistas & inibidores , Proteínas do Capsídeo/metabolismo , Macaca mulatta , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/efeitos dos fármacos
5.
Drug Metab Dispos ; 49(12): 1063-1069, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34599018

RESUMO

As an expansion investigation of drug-drug interaction (DDI) from previous clinical trials, additional plasma endogenous metabolites were quantitated in the same subjects to further identify the potential biomarkers of organic anion transporter (OAT) 1/3 inhibition. In the single dose, open label, three-phase with fixed order of treatments study, 14 healthy human volunteers orally received 1000 mg probenecid alone, or 40 mg furosemide alone, or 40 mg furosemide at 1 hour after receiving 1000 mg probenecid on days 1, 8, and 15, respectively. Endogenous metabolites including kynurenic acid, xanthurenic acid, indo-3-acetic acid, pantothenic acid, p-cresol sulfate, and bile acids in the plasma were measured by liquid chromatography-tandem mass spectrometry. The Cmax of kynurenic acids was significantly increased about 3.3- and 3.7-fold over the baseline values at predose followed by the treatment of probenecid alone or in combination with furosemide respectively. In comparison with the furosemide-alone group, the Cmax and area under the plasma concentration-time curve (AUC) up to 12 hours of kynurenic acid were significantly increased about 2.4- and 2.5-fold by probenecid alone, and 2.7- and 2.9-fold by probenecid plus furosemide, respectively. The increases in Cmax and AUC of plasma kynurenic acid by probenecid are comparable to the increases of furosemide Cmax and AUC reported previously. Additionally, the plasma concentrations of xanthurenic acid, indo-3-acetic acid, pantothenic acid, and p-cresol sulfate, but not bile acids, were also significantly elevated by probenecid treatments. The magnitude of effect size analysis for known potential endogenous biomarkers demonstrated that kynurenic acid in the plasma offers promise as a superior addition for early DDI assessment involving OAT1/3 inhibition. SIGNIFICANCE STATEMENT: This article reports that probenecid, an organic anion transporter (OAT) 1 and OAT3 inhibitor, significantly increased the plasma concentrations of kynurenic acid and several uremic acids in human subjects. Of those, the increases of plasma kynurenic acid exposure are comparable to the increases of furosemide by OAT1/3 inhibition. Effect size analysis for known potential endogenous biomarkers revealed that plasma kynurenic acid is a superior addition for early drug-drug interaction assessment involving OAT1/3 inhibition.


Assuntos
Biomarcadores Farmacológicos , Interações Medicamentosas/fisiologia , Furosemida/farmacologia , Ácido Cinurênico , Proteína 1 Transportadora de Ânions Orgânicos , Transportadores de Ânions Orgânicos Sódio-Independentes , Probenecid/farmacocinética , Adjuvantes Farmacêuticos/farmacocinética , Biomarcadores Farmacológicos/análise , Biomarcadores Farmacológicos/sangue , Cromatografia Líquida/métodos , Furosemida/farmacocinética , Voluntários Saudáveis , Humanos , Ácido Cinurênico/análise , Ácido Cinurênico/sangue , Proteína 1 Transportadora de Ânions Orgânicos/antagonistas & inibidores , Proteína 1 Transportadora de Ânions Orgânicos/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/antagonistas & inibidores , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Espectrometria de Massas em Tandem/métodos
6.
Adv Sci (Weinh) ; 8(12): e2005031, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34165896

RESUMO

Next-generation Li-ion batteries (LIBs) with higher energy density adopt some novel anode materials, which generally have the potential to exhibit higher capacity, superior rate performance as well as better cycling durability than conventional graphite anode, while on the other hand always suffer from larger active lithium loss (ALL) in the first several cycles. During the last two decades, various pre-lithiation strategies are developed to mitigate the initial ALL by presetting the extra Li sources to effectively improve the first Coulombic efficiency and thus achieve higher energy density as well as better cyclability. In this progress report, the origin of the huge initial ALL of the anode and its effect on the performance of full cells are first illustrated in theory. Then, various pre-lithiation strategies to resolve these issues are summarized, classified, and compared in detail. Moreover, the research progress of pre-lithiation strategies for the representative electrochemical systems are carefully reviewed. Finally, the current challenges and future perspectives are particularly analyzed and outlooked. This progress report aims to bring up new insights to reassess the significance of pre-lithiation strategies and offer a guideline for the research directions tailored for different applications based on the proposed pre-lithiation strategies summaries and comparisons.

7.
Hepatology ; 73(1): 53-67, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32246499

RESUMO

BACKGROUND AND AIMS: GS-9688 (selgantolimod) is an oral selective small molecule agonist of toll-like receptor 8 in clinical development for the treatment of chronic hepatitis B. In this study, we evaluated the antiviral efficacy of GS-9688 in woodchucks chronically infected with woodchuck hepatitis virus (WHV), a hepadnavirus closely related to hepatitis B virus. APPROACH AND RESULTS: WHV-infected woodchucks received eight weekly oral doses of vehicle, 1 mg/kg GS-9688, or 3 mg/kg GS-9688. Vehicle and 1 mg/kg GS-9688 had no antiviral effect, whereas 3 mg/kg GS-9688 induced a >5 log10 reduction in serum viral load and reduced WHV surface antigen (WHsAg) levels to below the limit of detection in half of the treated woodchucks. In these animals, the antiviral response was maintained until the end of the study (>5 months after the end of treatment). GS-9688 treatment reduced intrahepatic WHV RNA and DNA levels by >95% in animals in which the antiviral response was sustained after treatment cessation, and these woodchucks also developed detectable anti-WHsAg antibodies. The antiviral efficacy of weekly oral dosing with 3 mg/kg GS-9688 was confirmed in a second woodchuck study. The antiviral response to GS-9688 did not correlate with systemic GS-9688 or cytokine levels but was associated with transient elevation of liver injury biomarkers and enhanced proliferative response of peripheral blood mononuclear cells to WHV peptides. Transcriptomic analysis of liver biopsies taken prior to treatment suggested that T follicular helper cells and various other immune cell subsets may play a role in the antiviral response to GS-9688. CONCLUSIONS: Finite, short-duration treatment with a clinically relevant dose of GS-9688 is well tolerated and can induce a sustained antiviral response in WHV-infected woodchucks; the identification of a baseline intrahepatic transcriptional signature associated with response to GS-9688 treatment provides insights into the immune mechanisms that mediate this antiviral effect.


Assuntos
Antivirais/uso terapêutico , Vírus da Hepatite B da Marmota/efeitos dos fármacos , Vírus da Hepatite B da Marmota/genética , Hepatite B Crônica/tratamento farmacológico , Hexanóis/uso terapêutico , Pirimidinas/uso terapêutico , Receptor 8 Toll-Like/agonistas , Animais , Antivirais/farmacologia , DNA Viral/sangue , Modelos Animais de Doenças , Anticorpos Anti-Hepatite/sangue , Antígenos de Hepatite/sangue , Vírus da Hepatite B da Marmota/imunologia , Hepatite B Crônica/complicações , Hepatite B Crônica/imunologia , Hexanóis/farmacologia , Humanos , Marmota , Pirimidinas/farmacologia , Replicação Viral/efeitos dos fármacos
8.
Drug Metab Dispos ; 48(11): 1199-1209, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32892154

RESUMO

The eastern woodchuck (Marmota monax) is a hibernating species extensively used as an in vivo efficacy model for chronic human hepatitis B virus infection. Under laboratory conditions, woodchucks develop a pseudohibernation condition; thus, the pharmacokinetics (PK) of small-molecule therapeutics may be affected by the seasonal change. The seasonal PK of four probe compounds were characterized over 12 months in seven male and nine female laboratory-maintained woodchucks. These compounds were selected to study changes in oxidative metabolism [antipyrine (AP)], glucuronidation [raltegravir (RTG)], renal clearance [lamivudine (3TC)], and hepatic function [indocyanine green (ICG)]. Seasonal changes in physiologic parameters and PK were determined. Seasonal body weight increases were ≥30%. Seasonal changes in body temperature and heart rate were <10%. The mean AP exposure remained unchanged from April to August 2017, followed by a significant increase (≥1.0-fold) from August to December and subsequent decrease to baseline at the end of study. A similar trend was observed in RTG and 3TC exposures. The ICG exposure remained unchanged. No significant sex difference in PK was observed, although female woodchucks appeared to be less susceptible to seasonal PK and body weight changes. Significant seasonal PK changes for AP, RTG, and 3TC indicate decreases in oxidative metabolism, phase II glucuronidation, and renal clearance during pseudohibernation. The lack of seasonal change in ICG exposure suggests there are no significant changes in hepatic function. This information can be used to optimize the scheduling of woodchuck studies to avoid seasonally driven variation in drug PK. SIGNIFICANCE STATEMENT: Woodchuck is a hibernating species and is commonly used as a nonclinical model of hepatitis B infection. Investigation of seasonal PK changes is perhaps of greater interest to pharmaceutical industry scientists, who use the woodchuck model to optimize the scheduling of woodchuck studies to avoid seasonally driven variation in drug PK and/or toxicity. This information is also valuable to drug metabolism and veterinary scientists in understanding woodchuck's seasonal metabolism and behavior under the pseudohibernation condition.


Assuntos
Antivirais/farmacocinética , Hepatite B Crônica/tratamento farmacológico , Hibernação/fisiologia , Marmota/fisiologia , Taxa de Depuração Metabólica/fisiologia , Animais , Antivirais/uso terapêutico , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Humanos , Masculino , Estações do Ano
9.
Nature ; 584(7822): 614-618, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32612233

RESUMO

Oral antiretroviral agents provide life-saving treatments for millions of people living with HIV, and can prevent new infections via pre-exposure prophylaxis1-5. However, some people living with HIV who are heavily treatment-experienced have limited or no treatment options, owing to multidrug resistance6. In addition, suboptimal adherence to oral daily regimens can negatively affect the outcome of treatment-which contributes to virologic failure, resistance generation and viral transmission-as well as of pre-exposure prophylaxis, leading to new infections1,2,4,7-9. Long-acting agents from new antiretroviral classes can provide much-needed treatment options for people living with HIV who are heavily treatment-experienced, and additionally can improve adherence10. Here we describe GS-6207, a small molecule that disrupts the functions of HIV capsid protein and is amenable to long-acting therapy owing to its high potency, low in vivo systemic clearance and slow release kinetics from the subcutaneous injection site. Drawing on X-ray crystallographic information, we designed GS-6207 to bind tightly at a conserved interface between capsid protein monomers, where it interferes with capsid-protein-mediated interactions between proteins that are essential for multiple phases of the viral replication cycle. GS-6207 exhibits antiviral activity at picomolar concentrations against all subtypes of HIV-1 that we tested, and shows high synergy and no cross-resistance with approved antiretroviral drugs. In phase-1 clinical studies, monotherapy with a single subcutaneous dose of GS-6207 (450 mg) resulted in a mean log10-transformed reduction of plasma viral load of 2.2 after 9 days, and showed sustained plasma exposure at antivirally active concentrations for more than 6 months. These results provide clinical validation for therapies that target the functions of HIV capsid protein, and demonstrate the potential of GS-6207 as a long-acting agent to treat or prevent infection with HIV.


Assuntos
Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Proteínas do Capsídeo/antagonistas & inibidores , HIV-1/efeitos dos fármacos , Adolescente , Adulto , Fármacos Anti-HIV/química , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Linhagem Celular , Células Cultivadas , Farmacorresistência Viral/genética , Feminino , HIV-1/crescimento & desenvolvimento , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Replicação Viral/efeitos dos fármacos , Adulto Jovem
10.
J Med Chem ; 63(18): 10188-10203, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32407112

RESUMO

Toll-like receptor 8 (TLR8) recognizes pathogen-derived single-stranded RNA fragments to trigger innate and adaptive immune responses. Chronic hepatitis B (CHB) is associated with a dysfunctional immune response, and therefore a selective TLR8 agonist may be an effective treatment option. Structure-based optimization of a dual TLR7/8 agonist led to the identification of the selective TLR8 clinical candidate (R)-2-((2-amino-7-fluoropyrido[3,2-d]pyrimidin-4-yl)amino)-2-methylhexan-1-ol (GS-9688, (R)-7). Potent TLR8 agonism (IL-12p40 EC50 = 220 nM) and >100-fold TLR7 selectivity (IFN-α EC50 > 50 µM) was observed in human peripheral blood mononuclear cells (PBMCs). The TLR8-ectodomain:(R)-7 complex confirmed TLR8 binding and a direct ligand interaction with TLR8 residue Asp545. Oral (R)-7 had good absorption and high first pass clearance in preclinical species. A reduction in viral markers was observed in HBV-infected primary human hepatocytes treated with media from PBMCs stimulated with (R)-7, supporting the clinical development of (R)-7 for the treatment of CHB.


Assuntos
Antivirais/farmacologia , Hepatite B Crônica/tratamento farmacológico , Hexanóis/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Receptor 8 Toll-Like/agonistas , Administração Oral , Animais , Antivirais/administração & dosagem , Antivirais/síntese química , Antivirais/metabolismo , Cristalografia por Raios X , Cães , Descoberta de Drogas , Vírus da Hepatite B/efeitos dos fármacos , Hexanóis/administração & dosagem , Hexanóis/síntese química , Hexanóis/metabolismo , Humanos , Macaca fascicularis , Estrutura Molecular , Domínios Proteicos , Piridinas/administração & dosagem , Piridinas/síntese química , Piridinas/metabolismo , Pirimidinas/administração & dosagem , Pirimidinas/síntese química , Pirimidinas/metabolismo , Ratos , Relação Estrutura-Atividade , Receptor 8 Toll-Like/metabolismo
11.
Protein Sci ; 29(1): 298-305, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31721338

RESUMO

Significant efforts have been devoted in the last decade to improving molecular docking techniques to predict both accurate binding poses and ranking affinities. Some shortcomings in the field are the limited number of standard methods for measuring docking success and the availability of widely accepted standard data sets for use as benchmarks in comparing different docking algorithms throughout the field. In order to address these issues, we have created a Cross-Docking Benchmark server. The server is a versatile cross-docking data set containing 4,399 protein-ligand complexes across 95 protein targets intended to serve as benchmark set and gold standard for state-of-the-art pose and ranking prediction in easy, medium, hard, or very hard docking targets. The benchmark along with a customizable cross-docking data set generation tool is available at http://disco.csb.pitt.edu. We further demonstrate the potential uses of the server in questions outside of basic benchmarking such as the selection of the ideal docking reference structure.


Assuntos
Biologia Computacional/métodos , Proteínas/química , Proteínas/metabolismo , Algoritmos , Benchmarking , Sítios de Ligação , Desenho de Fármacos , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica , Navegador
12.
Nat Med ; 25(9): 1377-1384, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501601

RESUMO

People living with HIV (PLWH) have expressed concern about the life-long burden and stigma associated with taking pills daily and can experience medication fatigue that might lead to suboptimal treatment adherence and the emergence of drug-resistant viral variants, thereby limiting future treatment options1-3. As such, there is strong interest in long-acting antiretroviral (ARV) agents that can be administered less frequently4. Herein, we report GS-CA1, a new archetypal small-molecule HIV capsid inhibitor with exceptional potency against HIV-2 and all major HIV-1 types, including viral variants resistant to the ARVs currently in clinical use. Mechanism-of-action studies indicate that GS-CA1 binds directly to the HIV-1 capsid and interferes with capsid-mediated nuclear import of viral DNA, HIV particle production and ordered capsid assembly. GS-CA1 selects in vitro for unfit GS-CA1-resistant capsid variants that remain fully susceptible to other classes of ARVs. Its high metabolic stability and low solubility enabled sustained drug release in mice following a single subcutaneous dosing. GS-CA1 showed high antiviral efficacy as a long-acting injectable monotherapy in a humanized mouse model of HIV-1 infection, outperforming long-acting rilpivirine. Collectively, these results demonstrate the potential of ultrapotent capsid inhibitors as new long-acting agents for the treatment of HIV-1 infection.


Assuntos
Fármacos Anti-HIV/farmacologia , Proteínas do Capsídeo/antagonistas & inibidores , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Indazóis/farmacologia , Piridinas/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Fármacos Anti-HIV/uso terapêutico , Capsídeo/efeitos dos fármacos , Capsídeo/metabolismo , Proteínas do Capsídeo/genética , DNA Viral/efeitos dos fármacos , Preparações de Ação Retardada , Farmacorresistência Viral/efeitos dos fármacos , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/genética , HIV-1/patogenicidade , HIV-2/efeitos dos fármacos , HIV-2/patogenicidade , Humanos , Indazóis/uso terapêutico , Adesão à Medicação , Camundongos , Piridinas/uso terapêutico
13.
J Phys Chem Lett ; 9(17): 5100-5104, 2018 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-30130117

RESUMO

Increasing the loading of active materials by thickening the battery electrode coating can enhance the energy density of a Li-ion cell, but the trade-off is the much reduced Li+ transport kinetics. To reach the optimum energy and power density for thick electrodes, the effective chemical diffusion coefficient of Li+ ( DLi) must be maximized. However, the diffusion of Li+ inside an electrode is a complex process involving both microscopic and macroscopic processes. Fundamental understandings are needed on the rate-limiting process that governs the diffusion kinetics of Li+ to minimize the negative impact of the large electrode thickness on their electrochemical performance. In this work, lithium Ni-Mn-Co oxide (NMC) cathodes of various thicknesses ranging from 100 to 300 µm were used as a model system to study the rate-limiting diffusion process during charge/discharge. The rate-limiting diffusion coefficient of Li+ was investigated and quantified, which was correlated to the electrochemical performance degradation of thick electrodes. It is revealed here that the under-utilization of the active material was caused by the limited diffusion of Li+ inside the porous electrode, leading to a critical electrode thickness, beyond which the specific capacity was significantly reduced.

14.
Adv Mater ; 30(17): e1705670, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29527751

RESUMO

Among the various energy-storage systems, lithium-ion capacitors (LICs) are receiving intensive attention due to their high energy density, high power density, long lifetime, and good stability. As a hybrid of lithium-ion batteries and supercapacitors, LICs are composed of a battery-type electrode and a capacitor-type electrode and can potentially combine the advantages of the high energy density of batteries and the large power density of capacitors. Here, the working principle of LICs is discussed, and the recent advances in LIC electrode materials, particularly activated carbon and lithium titanate, as well as in electrolyte development are reviewed. The charge-storage mechanisms for intercalative pseudocapacitive behavior, battery behavior, and conventional pseudocapacitive behavior are classified and compared. Finally, the prospects and challenges associated with LICs are discussed. The overall aim is to provide deep insights into the LIC field for continuing research and development of second-generation energy-storage technologies.

15.
ACS Appl Mater Interfaces ; 10(8): 7155-7161, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29417815

RESUMO

A different strategy of capacity-control cycling under fixed upper and lower capacity/voltage limits is used in an attempt to seek an extended cycle life for Si nanoparticle-multiwalled carbon nanotube (Si-MW) electrodes for Li-ion batteries. For cells using Si-MW 1:1 (w/w) electrodes in the electrolyte of ethylene carbonate-diethyl carbonate-fluoroethylene carbonate (EC-DEC-FEC, 45:45:10 w/w/w) tested at a current of 1 mA, stable 326 charge/discharge cycles at a designated capacity of 506 mA h g-1 are attained. The new cycling protocol allows for the observation of a self-healing phenomenon by studying the specific capacities and charge/discharge end voltages. Prolonged cycling under capacity control (500 mA h g-1) and the interesting pattern of variations in the discharge/charge end voltage are successfully reproduced under different electrode/electrolyte and current conditions: Si-MW 3:2 in the electrolyte of DEC-FEC (1:1 w/w) at 1 mA (490 cycles), Si-MW 3:2 in DEC-FEC at 0.5 mA (483 cycles), and Si-MW 1:1 in DEC-FEC at 0.5 mA (576 cycles), which can be explained by applying the proposed self-healing mechanism as well.

16.
Drug Metab Dispos ; 46(3): 237-247, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29311136

RESUMO

Momelotinib (MMB), a small-molecule inhibitor of Janus kinase (JAK)1/2 and of activin A receptor type 1 (ACVR1), is in clinical development for the treatment of myeloproliferative neoplasms. The pharmacokinetics and disposition of [14C]MMB were characterized in a single-dose, human mass-balance study. Metabolism and the pharmacologic activity of key metabolites were elucidated in multiple in vitro and in vivo experiments. MMB was rapidly absorbed following oral dosing with approximately 97% of the radioactivity recovered, primarily in feces with urine as a secondary route. Mean blood-to-plasma [14C] area under the plasma concentration-time curve ratio was 0.72, suggesting low association of MMB and metabolites with blood cells. [14C]MMB-derived radioactivity was detectable in blood for ≤48 hours, suggesting no irreversible binding of MMB or its metabolites. The major circulating human metabolite, M21 (a morpholino lactam), is a potent inhibitor of JAK1/2 and ACVR1 in vitro. Estimation of pharmacological activity index suggests M21 contributes significantly to the pharmacological activity of MMB for the inhibition of both JAK1/2 and ACVR1. M21 was observed in disproportionately higher amounts in human plasma than in rat or dog, the rodent and nonrodent species used for the general nonclinical safety assessment of this molecule. This discrepancy was resolved with additional nonclinical studies wherein the circulating metabolites and drug-drug interactions were further characterized. The human metabolism of MMB was mediated primarily by multiple cytochrome P450 enzymes, whereas M21 formation involved initial P450 oxidation of the morpholine ring followed by metabolism via aldehyde oxidase.


Assuntos
Benzamidas/farmacocinética , Pirimidinas/farmacocinética , Adolescente , Adulto , Animais , Linhagem Celular , Linhagem Celular Tumoral , Sistema Enzimático do Citocromo P-450/metabolismo , Cães , Interações Medicamentosas/fisiologia , Feminino , Células Hep G2 , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Ratos , Adulto Jovem
17.
AIDS ; 32(1): 1-10, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-29112072

RESUMO

OBJECTIVE: Although bone marrow, liver, thymus (BLT)-humanized mice provide a robust model for HIV-1 infection and enable evaluation of cure strategies dependent on endogenous immune responses, most mice develop graft versus host disease (GVHD), limiting their utility for extended HIV cure studies. This study aimed to: evaluate the GVHD-resistant C57 black 6 (C57BL/6) recombination activating gene 2 (Rag2)γcCD47 triple knockout (TKO)-BLT mouse as a model to establish HIV-1 latency. Determine whether TKO-BLT mice could be maintained on antiretroviral therapy (ART) for extended periods of time. Assess the rapidity of viral rebound following therapy interruption. DESIGN: TKO-BLT mice were HIV-1 infected, treated with various ART regimens over extended periods of time and assayed for viral rebound following therapy interruption. METHODS: Daily subcutaneous injection and oral ART-mediated suppression of HIV-1 infection was tested at various doses in TKO-BLT mice. Mice were monitored for suppression of viremia and cellular HIV-1 RNA and DNA prior to and following therapy interruption. RESULTS: Mice remained healthy for 45 weeks posthumanization and could be treated with ART for up to 18 weeks. Viremia was suppressed to less than 200 copies/ml in the majority of mice with significant reductions in cellular HIV-1 RNA and DNA. Treatment interruption resulted in rapid viral recrudescence. CONCLUSION: HIV-1 latency can be maintained in TKO-BLT mice over extended periods on ART and rapid viral rebound occurs following therapy removal. The additional 15-18 weeks of healthy longevity compared with other BLT models provides sufficient time to examine the decay kinetics of the latent reservoir as well as observe delays in recrudescence in HIV-1 cure studies.


Assuntos
Modelos Animais de Doenças , Infecções por HIV/tratamento farmacológico , Camundongos Transgênicos , Administração Oral , Animais , Antirretrovirais/administração & dosagem , HIV-1/isolamento & purificação , HIV-1/fisiologia , Humanos , Injeções Subcutâneas , Camundongos Endogâmicos C57BL , Camundongos Knockout , Resultado do Tratamento , Carga Viral , Latência Viral
18.
Sci Rep ; 7: 41910, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28169329

RESUMO

Li ion battery (LIB) and electrochemical capacitor (EC) are considered as the most widely used energy storage systems (ESSs) because they can produce a high energy density or a high power density, but it is a huge challenge to achieve both the demands of a high energy density as well as a high power density on their own. A new hybrid Li ion capacitor (HyLIC), which combines the advantages of LIB and Li ion capacitor (LIC), is proposed. This device can successfully realize a potential match between LIB and LIC and can avoid the excessive depletion of electrolyte during the charge process. The galvanostatic charge-discharge cycling tests reveal that at low current, the HyLIC exhibits a high energy density, while at high current, it demonstrates a high power density. Ragone plot confirms that this device can make a synergetic balance between energy and power and achieve a highest energy density in the power density range of 80 to 300 W kg-1. The cycle life test proves that HyLIC exhibits a good cycle life and an excellent coulombic efficiency. The present study shows that HyLIC, which is capable of achieving a high energy density, a long cycle life and an excellent power density, has the potential to achieve the winning combination of a high energy and power density.

19.
Nanotechnology ; 28(5): 055701, 2017 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-28008886

RESUMO

Nanomaterials made from binary metal oxides are of increasing interest because of their versatility in applications from flexible electronics to portable chemical and biological sensors. Controlling the electrical properties of these materials is the first step in device implementation. Tin dioxide (SnO2) nanobelts (NB) synthesized by the vapor-liquid-solid mechanism have shown much promise in this regard. We explore the modification of devices prepared with single crystalline NBs by thermal annealing in vacuum and oxygen, resulting in a viable field-effect transistor (FET) for numerous applications at ambient temperature. An oxygen annealing step initially increases the device conductance by up to a factor of 105, likely through the modification of the surface defects of the NB, leading to Schottky barrier limited devices. A multi-step annealing procedure leads to further increase of the conductance by approximately 350% and optimization of the electronic properties. The effects of each step is investigated systematically on a single NB. The optimization of the electrical properties of the NBs makes possible the consistent production of channel-limited FETs and control of the device performance. Understanding these improvements on the electrical properties over the as-grown materials provides a pathway to enhance and tailor the functionalities of tin oxide nanostructures for a wide variety of optical, electronic, optoelectronic, and sensing applications that operate at room temperature.

20.
AIDS Res Hum Retroviruses ; 32(2): 163-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26150024

RESUMO

The use of nonhuman primate (NHP) models to study persistent residual virus and viral eradication strategies in combination antiretroviral therapy (cART)-treated individuals requires regimens that effectively suppress SIV replication to clinically relevant levels in macaques. We developed and evaluated two novel cART regimens in SIVmac239-infected rhesus macaques: (1) a "triple regimen" containing the nucleo(s/t)ide reverse transcriptase inhibitors emtricitabine (FTC) and tenofovir disoproxil fumarate [TDF, prodrug of tenofovir (TFV, PMPA)] with the integrase strand transfer inhibitor dolutegravir (DTG) (n = 3), or (2) a "quad regimen" containing the same three drugs plus the protease inhibitor darunavir (DRV) (n = 3), with each regimen coformulated for convenient administration by a single daily subcutaneous injection. Plasma drug concentrations were consistent across animals within the triple and quad regimen-treated groups, although DTG levels were lower in the quad regimen animals. Time to achieve plasma viral loads stably <30 viral RNA copies/ml ranged from 12 to 20 weeks of treatment between animals, and viral loads <30 viral RNA copies/ml plasma were maintained through 40 weeks of follow-up on cART. Notably, although we show virologic suppression and development of viral resistance in a separate cohort of SIV-infected animals treated with oral DRV monotherapy, the addition of DRV in the quad regimen did not confer an apparent virologic benefit during early treatment, hence the quad regimen-treated animals were switched to the triple regimen after 4 weeks. This coformulated triple cART regimen can be safely, conveniently, and sustainably administered to durably suppress SIV replication to clinically relevant levels in rhesus macaques.


Assuntos
Antirretrovirais/uso terapêutico , Farmacorresistência Viral , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Carga Viral/efeitos dos fármacos , Animais , Antirretrovirais/farmacocinética , Terapia Antirretroviral de Alta Atividade , Combinação de Medicamentos , Emtricitabina/farmacocinética , Emtricitabina/uso terapêutico , Inibidores de Integrase de HIV/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/farmacocinética , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Macaca mulatta , Oxazinas , Piperazinas , Piridonas , Inibidores da Transcriptase Reversa/uso terapêutico , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Tenofovir/farmacocinética , Tenofovir/uso terapêutico , Resultado do Tratamento
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