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1.
PLoS One ; 18(11): e0288052, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37917605

RESUMO

We examine climate-related disclosures in a large sample of reports published by banks that officially endorsed the recommendations of the Task Force for Climate-related Financial Disclosures (TCFD). In doing so, we introduce a new application of the zero-shot text classification. By developing a set of fine-grained TCFD labels, we show that zero-shot analysis is a useful tool for classifying climate-related disclosures without further model training. Overall, our findings indicate that corporate climate-related disclosures increased after the launch of the TCFD recommendations and following individual endorsements. However, there are marked differences in the extent of reporting by recommended disclosure topic, suggesting that some recommendations have not yet been fully met. Our findings yield important conclusions for the design of climate-related disclosure frameworks.


Assuntos
Conflito de Interesses , Revelação , Publicações
2.
Thorac Cardiovasc Surg ; 71(S 04): e1-e7, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36549306

RESUMO

BACKGROUND: Hoarseness due to laryngeal nerve injury is a known complication after cardiothoracic surgery involving the aortic arch. However, this complication is only rarely reported after catheter interventions. RESULTS: In this article we present the unusual case of a left-sided vocal cord paralysis in four patients after primary stenting of a re-coarctation, re-dilatation of a stented coarctation, a primary stenting of the left pulmonary artery (LPA), and prestenting for percutaneous pulmonary valve implantation with dilation of the LPA. After implanting bare metal stents, it is common practice, whilst contemplating the diameters of the adjacent structures, to optimize the stent diameter in a two-step procedure and dilate the stent until a maximum diameter is achieved and there is no residual gradient after applying this technique. Four of our patients experienced hoarseness after the intervention and a vocal cord paralysis was diagnosed. Angiography revealed no signs of extravasation or dissection. Clinical symptoms improved over the course of the following 6 months; patients with interventions at the aortic arch showed a complete remission, patients with procedures involving the LPA showed only mild regression of the symptoms. CONCLUSION: To our knowledge, this complication (Ortner's syndrome, cardiovocal syndrome) after such interventions has rarely been reported before. Although a rare complication, the recognition of these symptoms may support colleagues in managing affected patients. In addition, awareness for hoarseness after interventional therapies and systematic screening for this complication might help to identify patients at risk in the future.


Assuntos
Paralisia das Pregas Vocais , Humanos , Paralisia das Pregas Vocais/diagnóstico por imagem , Paralisia das Pregas Vocais/etiologia , Rouquidão/terapia , Rouquidão/complicações , Resultado do Tratamento , Aorta Torácica , Artéria Pulmonar , Nervo Laríngeo Recorrente
3.
Soc Sci Humanit Open ; 6(1): 100320, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966934

RESUMO

The spread of COVID-19 caused wide scale disruptions in the educational sector across the globe. Digital education, which involves the use of digital tools, virtual platforms and online learning, is seen as one of the viable alternatives to continue academic activities in such an environment. Higher education institutions have largely switched to this new mode of learning and continue to rely on digital mode in many parts of the world, due to the ongoing pandemic threat. However, learners' competency to effectively engage in online courses and the impact of their socioeconomic background on this competency has not been adequately addressed in the literature. The present study was an attempt to explore these aspects, as they are crucial to the success of digital education. The study was conducted with 833 undergraduate, postgraduate, and doctoral students from an agricultural university to assess their digital competencies and factors that influence effective participation in online courses. The Digital Competence Framework 2.0 of EU Science Hub (DIGCOMP) was adapted and used for this study. Our findings suggest that the learners have a satisfactory level of competence in most of the aspects of digital competence. Majority of the participants were relying on smart phones both as the device for accessing internet as well as for their learning activities. The results of a Tukey's difference in the mean test reveals that learners' digital competence varies significantly by gender, economic profile, and academic level. This finding can be attributed to the difference in their socio-economic background, which confirms digital divide among learners. Our findings have implications for the design of digital higher education strategies and institutional management to ensure effective learner participation, especially for higher education institutions in developing countries.

4.
Drug Metab Dispos ; 50(6): 858-866, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35149542

RESUMO

Characterization of the pharmacokinetics and biodistribution of therapeutic proteins (TPs) is a hot topic within the pharmaceutical industry, particularly with an ever-increasing catalog of novel modality TPs. Here, we review the current practices, and provide a summary of extensive cross-company discussions as well as a survey completed by International Consortium for Innovation and Quality members on this theme. A wide variety of in vitro, in vivo and in silico techniques are currently used to assess pharmacokinetics and biodistribution of TPs, and we discuss the relevance of these from an industry perspective, focusing on pharmacokinetic/pharmacodynamic understanding at the preclinical stage of development, and translation to human. We consider that the 'traditional in vivo biodistribution study' is becoming insufficient as a standalone tool, and thorough characterization of the interaction of the TP with its target(s), target biology, and off-target interactions at a microscopic scale are key to understand the overall biodistribution on a full-body scale. Our summary of the current challenges and our recommendations to address these issues could provide insight into the implementation of best practices in this area of drug development, and continued cross-company collaboration will be of tremendous value. SIGNIFICANCE STATEMENT: The Innovation and Quality Consortium Translational and ADME Sciences Leadership Group working group for the absorption, distribution, metabolism, and excretion of therapeutic proteins evaluates the current practices and challenges in characterizing the pharmacokinetics and biodistribution of therapeutic proteins during drug development, and proposes recommendations to address these issues. Incorporating the in vitro, in vivo and in silico approaches discussed herein may provide a pragmatic framework to increase early understanding of pharmacokinetic/pharmacodynamic relationships, and aid translational modeling for first-in-human dose predictions.


Assuntos
Indústria Farmacêutica , Farmacocinética , Indústria Farmacêutica/métodos , Humanos , Preparações Farmacêuticas , Distribuição Tecidual
5.
J Environ Manage ; 259: 109702, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32072948

RESUMO

Experts expect that climate change will soon have a severe impact on the lives of farmers in the region surrounding Kerala, India. This region, which is known for its monsoon climate (which involves a distinct temporal and spatial variation in rainfall), has experienced a decrease in annual rainfall over the last century. This study is aimed at investigating how smallholder farmers perceive climate change and at identifying the methods that these smallholders use to adapt to climate change. We use data collected from a survey of 215 households to compare the climate vulnerability of three watershed communities in Kerala. We find that the farmers perceive substantial increases in both temperature and the unpredictability of monsoons; this is in accordance with actual observed weather trends. The selection of effective adaptation strategies is one of the key challenges that smallholders face as they seek to reduce their vulnerability. The surveyed households simultaneously use various adaptation methods, including information and communication technology, crop and farm diversification, social networking through cooperatives, and soil and water conservation measures. The results of a binary regression model reveal that the household head's age, education and gender, as well as the farm's size and the household's size, assets, livestock ownership, poverty status and use of extension services, are all significantly correlated with the households' choices regarding adaptations to cope with climate change.


Assuntos
Agricultura , Fazendeiros , Animais , Mudança Climática , Fazendas , Humanos , Índia
6.
Drug Metab Dispos ; 47(12): 1443-1456, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31748266

RESUMO

For therapeutic proteins, the currently established standard development path generally does not foresee biotransformation studies by default because it is well known that the clearance of therapeutic proteins proceeds via degradation to small peptides and individual amino acids. In contrast to small molecules, there is no general need to identify enzymes involved in biotransformation because this information is not relevant for drug-drug interaction assessment and for understanding the clearance of a therapeutic protein. Nevertheless, there are good reasons to embark on biotransformation studies, especially for complex therapeutic proteins. Typical triggers are unexpected rapid clearance, species differences in clearance not following the typical allometric relationship, a mismatch in the pharmacokinetics/pharmacodynamics (PK/PD) relationship, and the need to understand observed differences between the results of multiple bioanalytical methods (e.g., total vs. target-binding competent antibody concentrations). Early on during compound optimization, knowledge on protein biotransformation may help to design more stable drug candidates with favorable in vivo PK properties. Understanding the biotransformation of a therapeutic protein may also support designing and understanding the bioanalytical assay and ultimately the PK/PD assessment. Especially in cases where biotransformation products are pharmacologically active, quantification and assessment of their contribution to the overall pharmacological effect can be important for establishing a PK/PD relationship and extrapolation to humans. With the increasing number of complex therapeutic protein formats, the need for understanding the biotransformation of therapeutic proteins becomes more urgent. This article provides an overview on biotransformation processes, proteases involved, strategic considerations, regulatory guidelines, literature examples for in vitro and in vivo biotransformation, and technical approaches to study protein biotransformation. SIGNIFICANCE STATEMENT: Understanding the biotransformation of complex therapeutic proteins can be crucial for establishing a pharmacokinetic/pharmacodynamic relationship. This article will highlight scientific, strategic, regulatory, and technological features of protein biotransformation.


Assuntos
Preparações Farmacêuticas/metabolismo , Proteínas/farmacocinética , Bibliotecas de Moléculas Pequenas/farmacocinética , Animais , Biotransformação , Interações Medicamentosas , Humanos , Preparações Farmacêuticas/administração & dosagem , Proteínas/administração & dosagem , Proteínas/farmacologia , Bibliotecas de Moléculas Pequenas/administração & dosagem , Bibliotecas de Moléculas Pequenas/farmacologia
7.
Sci Transl Med ; 11(497)2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31217335

RESUMO

A pumpless, reconfigurable, multi-organ-on-a-chip system containing recirculating serum-free medium can be used to predict preclinical on-target efficacy, metabolic conversion, and measurement of off-target toxicity of drugs using functional biological microelectromechanical systems. In the first configuration of the system, primary human hepatocytes were cultured with two cancer-derived human bone marrow cell lines for antileukemia drug analysis in which diclofenac and imatinib demonstrated a cytostatic effect on bone marrow cancer proliferation. Liver viability was not affected by imatinib; however, diclofenac reduced liver viability by 30%. The second configuration housed a multidrug-resistant vulva cancer line, a non-multidrug-resistant breast cancer line, primary hepatocytes, and induced pluripotent stem cell-derived cardiomyocytes. Tamoxifen reduced viability of the breast cancer cells only after metabolite generation but did not affect the vulva cancer cells except when coadministered with verapamil, a permeability glycoprotein inhibitor. Both tamoxifen alone and coadministration with verapamil produced off-target cardiac effects as indicated by a reduction of contractile force, beat frequency, and conduction velocity but did not affect viability. These systems demonstrate the utility of a human cell-based in vitro culture system to evaluate both on-target efficacy and off-target toxicity for parent drugs and their metabolites; these systems can augment and reduce the use of animals and increase the efficiency of drug evaluations in preclinical studies.


Assuntos
Antineoplásicos/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Diclofenaco/farmacologia , Humanos , Mesilato de Imatinib/farmacologia , Dispositivos Lab-On-A-Chip , Tamoxifeno/farmacologia , Verapamil/farmacologia
8.
Sci Rep ; 9(1): 4074, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30858459

RESUMO

As more and more protein biotherapeutics enter the drug discovery pipelines, there is an increasing interest in tools for mechanistic drug metabolism investigations of biologics in order to identify and prioritize the most promising candidates. Understanding or even predicting the in vivo clearance of biologics and to support translational pharmacokinetic modeling activities is essential, however there is a lack of effective and validated in vitro cellular tools. Although different mechanisms have to be adressed in the context of biologics disposition, the scope is not comparable to the nowadays widely established tools for early characterization of small molecule disposition. Here, we describe a biotransformation study of the fusion protein tetranectin apolipoprotein A1 by cellular systems. The in vivo biotransformation of tetranectin apolipoprotein A1 has been described previously, and the same major biotransformation product could also be detected in vitro, by a targeted and highly sensitive detection method based on chymotrypsin digest. In addition, the protease responsible for the formation of this biotransformation product could be elucidated to be DPP4. To our knowledge, this is one of the first reports of an in vitro biotransformation study by cells of a therapeutic protein.


Assuntos
Apolipoproteína A-I/genética , Biotransformação/genética , Dipeptidil Peptidase 4/química , Lectinas Tipo C/genética , Proteínas Recombinantes de Fusão/genética , Apolipoproteína A-I/química , Quimotripsina/farmacologia , Dipeptidil Peptidase 4/farmacologia , Descoberta de Drogas , Humanos , Lectinas Tipo C/química , Processamento de Proteína Pós-Traducional , Proteômica/métodos , Proteínas Recombinantes de Fusão/química
9.
Clin Pharmacol Ther ; 104(5): 916-932, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30137645

RESUMO

Bile salt export pump (BSEP) inhibition has emerged as an important mechanism that may contribute to the initiation of human drug-induced liver injury (DILI). Proactive evaluation and understanding of BSEP inhibition is recommended in drug discovery and development to aid internal decision making on DILI risk. BSEP inhibition can be quantified using in vitro assays. When interpreting assay data, it is important to consider in vivo drug exposure. Currently, this can be undertaken most effectively by consideration of total plasma steady state drug concentrations (Css,plasma ). However, because total drug concentrations are not predictive of pharmacological effect, the relationship between total exposure and BSEP inhibition is not causal. Various follow-up studies can aid interpretation of in vitro BSEP inhibition data and may be undertaken on a case-by-case basis. BSEP inhibition is one of several mechanisms by which drugs may cause DILI, therefore, it should be considered alongside other mechanisms when evaluating possible DILI risk.


Assuntos
Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Bile/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Desenvolvimento de Medicamentos/métodos , Descoberta de Drogas/métodos , Fígado/efeitos dos fármacos , Moduladores de Transporte de Membrana/toxicidade , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/química , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Simulação por Computador , Desenho Assistido por Computador , Desenho de Fármacos , Humanos , Técnicas In Vitro , Fígado/metabolismo , Moduladores de Transporte de Membrana/química , Modelos Biológicos , Conformação Proteica , Medição de Risco , Fatores de Risco , Relação Estrutura-Atividade
10.
Drug Metab Dispos ; 46(6): 865-878, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29487142

RESUMO

Since the introduction of metabolites in safety testing (MIST) guidance by the Food and Drug Administration in 2008, major changes have occurred in the experimental methods for the identification and quantification of metabolites, ways to evaluate coverage of metabolites, and the timing of critical clinical and nonclinical studies to generate this information. In this cross-industry review, we discuss how the increased focus on human drug metabolites and their potential contribution to safety and drug-drug interactions has influenced the approaches taken by industry for the identification and quantitation of human drug metabolites. Before the MIST guidance was issued, the method of choice for generating comprehensive metabolite profile was radio chromatography. The MIST guidance increased the focus on human drug metabolites and their potential contribution to safety and drug-drug interactions and led to changes in the practices of drug metabolism scientists. In addition, the guidance suggested that human metabolism studies should also be accelerated, which has led to more frequent determination of human metabolite profiles from multiple ascending-dose clinical studies. Generating a comprehensive and quantitative profile of human metabolites has become a more urgent task. Together with technological advances, these events have led to a general shift of focus toward earlier human metabolism studies using high-resolution mass spectrometry and to a reduction in animal radiolabel absorption/distribution/metabolism/excretion studies. The changes induced by the MIST guidance are highlighted by six case studies included herein, reflecting different stages of implementation of the MIST guidance within the pharmaceutical industry.


Assuntos
Descoberta de Drogas/normas , Inativação Metabólica/fisiologia , Preparações Farmacêuticas/metabolismo , Animais , Indústria Farmacêutica/normas , Interações Medicamentosas/fisiologia , Humanos , Estados Unidos , United States Food and Drug Administration
11.
Toxicol Sci ; 163(2): 409-419, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28329870

RESUMO

A number of drugs can cause precipitates within renal tubules leading to crystal nephropathy. Crystal nephropathy is usually an exposure-related finding and is not uncommon in preclinical studies, where high doses are tested. An understanding of the nature of precipitates is important for human risk assessment and further development. Our aim was to investigate the ability of various imaging techniques to detect the presence of drugs or metabolites in renal crystals. We applied matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS) imaging, Raman and infrared microspectroscopy, scanning electron microscopy coupled with energy dispersive X-ray (SEM/EDX) spectroscopy and standard histopathology to cases of drug-induced crystal nephropathy, induced in rodents and primates by 4 compounds. MALDI-FTICR MS imaging enabled the identification of the drug-related crystal content in all 4 cases of nephropathy, without reference material and with high accuracy. Crystals were composed of unchanged parent drug and/or metabolites. Similar results were obtained using Raman and infrared microspectroscopy for 2 compounds. In the absence of reference standards of metabolites, Raman and infrared microspectroscopy showed that the crystals consisted of components similar, but not identical, to the administered drug for the other compounds, a limitation for these techniques. SEM/EDX showed which counter ions were colocalized with the identified drug-related material, complementing the MALDI-FTICR MS findings. Therefore, we recommend MALDI-FTICR MS as a first-line methodology to characterize crystal nephropathies. Raman and infrared microspectroscopy may be useful when MALDI-FTICR MS imaging cannot be applied. SEM/EDX could be considered as a complementary technology.


Assuntos
Injúria Renal Aguda/diagnóstico por imagem , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico por imagem , Rim/efeitos dos fármacos , Preparações Farmacêuticas/química , Animais , Cristalização , Avaliação Pré-Clínica de Medicamentos , Rim/diagnóstico por imagem , Macaca fascicularis , Camundongos , Estrutura Molecular , Preparações Farmacêuticas/análise , Ratos , Especificidade da Espécie , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrofotometria Infravermelho , Análise Espectral Raman
12.
MAbs ; 9(5): 781-791, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28440708

RESUMO

Monoclonal antibodies (mAbs) are a rapidly growing drug class for which great efforts have been made to optimize certain molecular features to achieve the desired pharmacokinetic (PK) properties. One approach is to engineer the interactions of the mAb with the neonatal Fc receptor (FcRn) by introducing specific amino acid sequence mutations, and to assess their effect on the PK profile with in vivo studies. Indeed, FcRn protects mAbs from intracellular degradation, thereby prolongs antibody circulation time in plasma and modulates its systemic clearance. To allow more efficient and focused mAb optimization, in vitro input that helps to identify and quantitatively predict the contribution of different processes driving non-target mediated mAb clearance in vivo and supporting translational PK modeling activities is essential. With this aim, we evaluated the applicability and in vivo-relevance of an in vitro cellular FcRn-mediated transcytosis assay to explain the PK behavior of 25 mAbs in rat or monkey. The assay was able to capture species-specific differences in IgG-FcRn interactions and overall correctly ranked Fc mutants according to their in vivo clearance. However, it could not explain the PK behavior of all tested IgGs, indicating that mAb disposition in vivo is a complex interplay of additional processes besides the FcRn interaction. Overall, the transcytosis assay was considered suitable to rank mAb candidates for their FcRn-mediated clearance component before extensive in vivo testing, and represents a first step toward a multi-factorial in vivo clearance prediction approach based on in vitro data.


Assuntos
Anticorpos Monoclonais Murinos/farmacocinética , Bioensaio/métodos , Antígenos de Histocompatibilidade Classe I/imunologia , Receptores Fc/imunologia , Transcitose/imunologia , Animais , Anticorpos Monoclonais Murinos/imunologia , Anticorpos Monoclonais Murinos/farmacologia , Macaca fascicularis , Camundongos , Ratos , Ratos Wistar
13.
AAPS J ; 19(2): 534-550, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28050713

RESUMO

Early prediction of human clearance is often challenging, in particular for the growing number of low-clearance compounds. Long-term in vitro models have been developed which enable sophisticated hepatic drug disposition studies and improved clearance predictions. Here, the cell line HepG2, iPSC-derived hepatocytes (iCell®), the hepatic stem cell line HepaRG™, and human hepatocyte co-cultures (HµREL™ and HepatoPac®) were compared to primary hepatocyte suspension cultures with respect to their key metabolic activities. Similar metabolic activities were found for the long-term models HepaRG™, HµREL™, and HepatoPac® and the short-term suspension cultures when averaged across all 11 enzyme markers, although differences were seen in the activities of CYP2D6 and non-CYP enzymes. For iCell® and HepG2, the metabolic activity was more than tenfold lower. The micropatterned HepatoPac® model was further evaluated with respect to clearance prediction. To assess the in vitro parameters, pharmacokinetic modeling was applied. The determination of intrinsic clearance by nonlinear mixed-effects modeling in a long-term model significantly increased the confidence in the parameter estimation and extended the sensitive range towards 3% of liver blood flow, i.e., >10-fold lower as compared to suspension cultures. For in vitro to in vivo extrapolation, the well-stirred model was used. The micropatterned model gave rise to clearance prediction in man within a twofold error for the majority of low-clearance compounds. Further research is needed to understand whether transporter activity and drug metabolism by non-CYP enzymes, such as UGTs, SULTs, AO, and FMO, is comparable to the in vivo situation in these long-term culture models.


Assuntos
Hepatócitos/metabolismo , Fígado/metabolismo , Modelos Biológicos , Farmacocinética , Técnicas de Cocultura , Citocromo P-450 CYP2D6/metabolismo , Enzimas/metabolismo , Células Hep G2 , Hepatócitos/enzimologia , Humanos , Fígado/enzimologia , Dinâmica não Linear , Preparações Farmacêuticas/metabolismo , Fatores de Tempo
14.
Xenobiotica ; 47(2): 144-153, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27123695

RESUMO

1. The emerging technique of employing intravenous microdose administration of an isotope tracer concomitantly with an [14C]-labeled oral dose was used to characterize the disposition and absolute bioavailability of a novel metabotropic glutamate 5 (mGlu5) receptor antagonist under clinical development for major depressive disorder (MDD). 2. Six healthy volunteers received a single 1 mg [12C/14C]-basimglurant (2.22 MBq) oral dose and a concomitant i.v. tracer dose of 100 µg of [13C6]-basimglurant. Concentrations of [12C]-basimglurant and the stable isotope [13C6]-basimglurant were determined in plasma by a specific LC/MS-MS method. Total [14C] radioactivity was determined in whole blood, plasma, urine and feces by liquid scintillation counting. Metabolic profiling was conducted in plasma, urine, blood cell pellet and feces samples. 3. The mean absolute bioavailability after oral administration (F) of basimglurant was ∼67% (range 45.7-77.7%). The major route of [14C]-radioactivity excretion, primarily in form of metabolites, was in urine (mean recovery 73.4%), with the remainder excreted in feces (mean recovery 26.5%). The median tmax for [12C]-basimglurant after the oral administration was 0.71 h (range 0.58-1.00) and the mean terminal half-life was 77.2 ± 38.5 h. Terminal half-life for the [14C]-basimglurant was 178 h indicating presence of metabolites with a longer terminal half-life. Five metabolites were identified with M1-Glucuronide as major and the others in trace amounts. There was minimal binding of drug to RBCs. IV pharmacokinetics was characterized with a mean ± SD CL of 11.8 ± 7.4 mL/h and a Vss of 677 ± 229 L. 4. The double-tracer technique used in this study allowed to simultaneously characterize the absolute bioavailability and disposition characteristics of the new oral molecular entity in a single study.


Assuntos
Imidazóis/farmacocinética , Piridinas/farmacocinética , Administração Oral , Área Sob a Curva , Meia-Vida , Humanos
15.
Arch Toxicol ; 91(1): 131-142, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27766365

RESUMO

Drug-induced liver injury (DILI) is a major concern for drug developers, regulators and clinicians. It is triggered by drug and xenobiotic insults leading to liver impairment or damage, in the worst-case liver failure. In contrast to acute "intrinsic" hepatotoxicity, DILI typically manifests in a very small subset of the population under treatment with no clear dose relationship and inconsistent temporal patterns and is therefore termed an idiosyncratic event. Involved are multifactorial, compound-dependent mechanisms and host-specific factors, making the prediction in preclinical test systems very challenging. While preclinical safety studies in animals usually are able to capture direct, acute liver toxicities, they are less predictive for human DILI, where specific, human-derived in vitro models can potentially close the gap. On one hand, mechanistic approaches addressing key mechanisms involved in DILI in well-characterized and standardized in vitro test systems have been developed. On the other hand, co-cultures of different cell types, including patient- and/or stem cell-derived cells, in a three-dimensional setup allow for prolonged incubations and multiplexed readouts. Such complex setups might better reflect multifactorial human DILI. One major challenge is that for many compounds with human DILI the underlying mechanisms are not yet fully understood, complicating establishment and validation of predictive cellular tools. A tiered approach including rapid mechanism-based in vitro screens followed by confirmatory tests in more physiologically relevant models might allow minimizing DILI risk early on in vitro. Such complex, integrated approaches will gain from larger collaborations in multidisciplinary groups bringing existing knowledge and state-of-the-art technology together.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Avaliação Pré-Clínica de Medicamentos , Drogas em Investigação/efeitos adversos , Modelos Biológicos , Xenobióticos/toxicidade , Alternativas aos Testes com Animais/tendências , Animais , Linhagem Celular , Células Cultivadas , Técnicas de Cocultura , Biologia Computacional , Avaliação Pré-Clínica de Medicamentos/tendências , Drogas em Investigação/metabolismo , Sistemas Inteligentes , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Reconhecimento Automatizado de Padrão/tendências , Reprodutibilidade dos Testes , Pesquisa Translacional Biomédica/tendências , Xenobióticos/metabolismo
16.
Drug Discov Today ; 22(5): 751-756, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27903430

RESUMO

Many pharmaceutical companies aim to reduce reactive metabolite formation by chemical modification at early stages of drug discovery. A practice often applied is the detection of stable trapping products of electrophilic intermediates with nucleophilic trapping reagents to guide rational structure-based drug design. This contribution delineates this strategy to minimize the potential for reactive metabolite formation of clinical candidates during preclinical drug optimization, exemplified by the experience at Roche over the past decade. For the majority of research programs it was possible to proceed with compounds optimized for reduced covalent binding potential. Such optimized candidates are expected to have a higher likelihood of succeeding throughout the development processes, resulting in safer drugs.


Assuntos
Avaliação Pré-Clínica de Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Ativação Metabólica , Bioensaio , Glutationa/metabolismo , Humanos , Preparações Farmacêuticas/metabolismo , Risco
17.
Xenobiotica ; 46(6): 483-94, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26405846

RESUMO

1. In recent years, the minipig is increasingly used as a test species in non-clinical assessment of drug candidates. While there is good scientific evidence available concerning cytochrome P450-mediated metabolism in minipig, the knowledge of other metabolic pathways is more limited. 2. The aim of this study was to provide an understanding of when, why, and how drug metabolism in minipig differs from other species commonly used in non-clinical studies. In-house cross-species metabolite profile comparisons in hepatocytes and microsomes of 38 Roche development compounds were retrospectively analyzed to compare the metabolism among minipig, human, rat, dog, monkey, rabbit and mouse. 3. A significant contributor to the elevated metabolism observed for certain compounds in minipig was identified as amide hydrolysis. The hepatic amide hydrolysis activity in minipig was further investigated in subcellular liver fractions and a structure-activity relationship was established. When structural motifs according to the established SAR are excluded, coverage of major human metabolic pathways was shown to be higher in minipig than in dog, and only slightly lower than in cynomolgus monkey. 4. A strategy is presented for early identification of drug compounds which might not be suited to further investigation in minipig due to excessive hydrolytic metabolism.


Assuntos
Amidas/metabolismo , Preparações Farmacêuticas/metabolismo , Amidas/química , Animais , Western Blotting , Carboxilesterase/metabolismo , Celecoxib/metabolismo , Hepatócitos/metabolismo , Humanos , Hidrólise , Fígado/metabolismo , Metaboloma , Microssomos Hepáticos/metabolismo , Especificidade da Espécie , Relação Estrutura-Atividade , Frações Subcelulares/metabolismo , Suínos , Porco Miniatura
18.
J Pharmacol Exp Ther ; 353(1): 213-33, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25665805

RESUMO

Major depressive disorder (MDD) is a serious public health burden and a leading cause of disability. Its pharmacotherapy is currently limited to modulators of monoamine neurotransmitters and second-generation antipsychotics. Recently, glutamatergic approaches for the treatment of MDD have increasingly received attention, and preclinical research suggests that metabotropic glutamate receptor 5 (mGlu5) inhibitors have antidepressant-like properties. Basimglurant (2-chloro-4-[1-(4-fluoro-phenyl)-2,5-dimethyl-1H-imidazol-4-ylethynyl]-pyridine) is a novel mGlu5 negative allosteric modulator currently in phase 2 clinical development for MDD and fragile X syndrome. Here, the comprehensive preclinical pharmacological profile of basimglurant is presented with a focus on its therapeutic potential for MDD and drug-like properties. Basimglurant is a potent, selective, and safe mGlu5 inhibitor with good oral bioavailability and long half-life supportive of once-daily administration, good brain penetration, and high in vivo potency. It has antidepressant properties that are corroborated by its functional magnetic imaging profile as well as anxiolytic-like and antinociceptive features. In electroencephalography recordings, basimglurant shows wake-promoting effects followed by increased delta power during subsequent non-rapid eye movement sleep. In microdialysis studies, basimglurant had no effect on monoamine transmitter levels in the frontal cortex or nucleus accumbens except for a moderate increase of accumbal dopamine, which is in line with its lack of pharmacological activity on monoamine reuptake transporters. These data taken together, basimglurant has favorable drug-like properties, a differentiated molecular mechanism of action, and antidepressant-like features that suggest the possibility of also addressing important comorbidities of MDD including anxiety and pain as well as daytime sleepiness and apathy or lethargy.


Assuntos
Ansiolíticos/farmacologia , Antidepressivos/farmacologia , Depressão/tratamento farmacológico , Imidazóis/farmacologia , Piridinas/farmacologia , Receptor de Glutamato Metabotrópico 5/antagonistas & inibidores , Regulação Alostérica , Animais , Ansiolíticos/farmacocinética , Ansiolíticos/uso terapêutico , Antidepressivos/farmacocinética , Antidepressivos/uso terapêutico , Monoaminas Biogênicas/metabolismo , Encéfalo/metabolismo , Células Cultivadas , Cricetulus , Depressão/metabolismo , Depressão/psicologia , Agonismo Inverso de Drogas , Eletroencefalografia , Feminino , Imidazóis/farmacocinética , Imidazóis/uso terapêutico , Macaca fascicularis , Masculino , Camundongos , Dor/tratamento farmacológico , Dor/fisiopatologia , Piridinas/farmacocinética , Piridinas/uso terapêutico , Ensaio Radioligante , Ratos Sprague-Dawley , Ratos Wistar , Receptor de Glutamato Metabotrópico 5/metabolismo , Bexiga Urinária Hiperativa/tratamento farmacológico , Bexiga Urinária Hiperativa/fisiopatologia
19.
J Med Chem ; 58(3): 1358-71, 2015 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-25565255

RESUMO

Negative allosteric modulators (NAMs) of metabotropic glutamate receptor 5 (mGlu5) have potential for the treatment of psychiatric diseases including depression, fragile X syndrome (FXS), anxiety, obsessive-compulsive disorders, and levodopa induced dyskinesia in Parkinson's disease. Herein we report the optimization of a weakly active screening hit 1 to the potent and selective compounds chloro-4-[1-(4-fluorophenyl)-2,5-dimethyl-1H-imidazol-4-ylethynyl]pyridine (basimglurant, 2) and 2-chloro-4-((2,5-dimethyl-1-(4-(trifluoromethoxy)phenyl)-1H-imidazol-4-yl)ethynyl)pyridine (CTEP, 3). Compound 2 is active in a broad range of anxiety tests reaching the same efficacy but at a 10- to 100-fold lower dose compared to diazepam and is characterized by favorable DMPK properties in rat and monkey as well as an excellent preclinical safety profile and is currently in phase II clinical studies for the treatment of depression and fragile X syndrome. Analogue 3 is the first reported mGlu5 NAM with a long half-life in rodents and is therefore an ideal tool compound for chronic studies in mice and rats.


Assuntos
Depressão/tratamento farmacológico , Descoberta de Drogas , Síndrome do Cromossomo X Frágil/tratamento farmacológico , Imidazóis/farmacologia , Piridinas/farmacologia , Receptor de Glutamato Metabotrópico 5/antagonistas & inibidores , Regulação Alostérica/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Humanos , Imidazóis/síntese química , Imidazóis/química , Macaca mulatta , Masculino , Camundongos , Camundongos Endogâmicos , Estrutura Molecular , Piridinas/síntese química , Piridinas/química , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Relação Estrutura-Atividade
20.
Xenobiotica ; 45(3): 230-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25350082

RESUMO

Abstract 1. The metabolism and drug-drug interaction (DDI) risk of tofogliflozin, a potent and highly specific sodium-glucose co-transporter 2 inhibitor, were evaluated by in vitro studies using human liver microsomes, human hepatocytes, and recombinant human CYPs. 2. The main metabolite of tofogliflozin was the carboxylated derivative (M1) in human hepatocytes, which was the same as in vivo. The metabolic pathway of tofogliflozin to M1 was considered to be as follows: first, tofogliflozin was catalyzed to the primary hydroxylated derivative (M4) by CYP2C18, CYP4A11 and CYP4F3B, then M4 was oxidized to M1. 3. Tofogliflozin had no induction potential on CYP1A2 and CYP3A4. Neither tofogliflozin nor M1 had inhibition potential on CYPs, with the exception of a weak CYP2C19 inhibition by M1. 4. Not only are multiple metabolic enzymes involved in the tofogliflozin metabolism, but the drug is also excreted into urine after oral administration, indicating that tofogliflozin is eliminated through multiple pathways. Thus, the exposure of tofogliflozin would not be significantly altered by DDI caused by any co-administered drugs. Also, tofogliflozin seems not to cause significant DDI of co-administered drugs because tofogliflozin has no CYP induction or inhibition potency, and the main metabolite M1 has no clinically relevant CYP inhibition potency.


Assuntos
Compostos Benzidrílicos/metabolismo , Glucosídeos/metabolismo , Hepatócitos/metabolismo , Metabolômica/métodos , Microssomos Hepáticos/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose , Compostos Benzidrílicos/química , Radioisótopos de Carbono , Coenzimas/metabolismo , Inibidores das Enzimas do Citocromo P-450/farmacologia , Sistema Enzimático do Citocromo P-450/biossíntese , Interações Medicamentosas , Indução Enzimática/efeitos dos fármacos , Glucosídeos/química , Hepatócitos/efeitos dos fármacos , Hepatócitos/enzimologia , Humanos , Concentração Inibidora 50 , Redes e Vias Metabólicas/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Ligação Proteica/efeitos dos fármacos , Proteínas Recombinantes/metabolismo , Transportador 2 de Glucose-Sódio/metabolismo , Fatores de Tempo
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