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1.
Artigo em Inglês | MEDLINE | ID: mdl-31061156

RESUMO

Infections caused by antibiotic-resistant Gram-negative bacteria expressing extended-spectrum ß-lactamases and carbapenemases are a growing global problem resulting in increased morbidity and mortality with limited treatment options. LYS228 is a novel intravenous monobactam antibiotic targeting penicillin binding protein 3 with potent activity against Enterobacteriaceae, including multidrug-resistant clinical isolates expressing serine and metallo-ß-lactamases. In this study, we evaluated the safety, tolerability, and pharmacokinetics of single and multiple intravenous doses of LYS228 in healthy volunteers. LYS228 was safe: no serious adverse events were reported. Adverse events, with the exception of catheter-related events, occurred sporadically, with similar incidences between LYS228 and placebo groups. No apparent adverse event-dose relationship was identified. LYS228 was not associated with any clinically significant dose-related hematologic, hepatic, or renal laboratory abnormalities. The most frequently observed adverse events were local injection site reactions, noted in 91.7% and 75.0% of subjects administered multiple doses of LYS228 and placebo, respectively. LYS228 demonstrated pharmacokinetic properties consistent with those of other ß-lactam antibiotics, with systemic exposures slightly greater than dose proportional, short terminal half-lives (between 1.0 and 1.6 h) with no significant accumulation, and rapid clearance predominantly through urinary excretion.


Assuntos
Antibacterianos/efeitos adversos , Antibacterianos/farmacocinética , Monobactamas/efeitos adversos , Monobactamas/farmacocinética , Adulto , Antibacterianos/administração & dosagem , Proteínas de Bactérias/metabolismo , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/metabolismo , Feminino , Voluntários Saudáveis , Humanos , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Monobactamas/administração & dosagem , beta-Lactamases/metabolismo
2.
Arch Toxicol ; 92(5): 1877-1891, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29556671

RESUMO

A high incidence of hemangiosarcoma (HSA) was observed in mice treated for 2 years with siponimod, a sphingosine-1-phosphate receptor 1 (S1P1) functional antagonist, while no such tumors were observed in rats under the same treatment conditions. In 3-month rat (90 mg/kg/day) and 9-month mouse (25 and 75 mg/kg/day) in vivo mechanistic studies, vascular endothelial cell (VEC) activation was observed in both species, but VEC proliferation and persistent increases in circulating placental growth factor 2 (PLGF2) were only seen in the mouse. In mice, these effects were sustained over the 9-month study duration, while in rats increased mitotic gene expression was present at day 3 only and PLGF2 was induced only during the first week of treatment. In the mouse, the persistent VEC activation, mitosis induction, and PLGF2 stimulation likely led to sustained neo-angiogenesis which over life-long treatment may result in HSA formation. In rats, despite sustained VEC activation, the transient mitotic and PLGF2 stimuli did not result in the formation of HSA. In vitro, the mouse and rat primary endothelial cell cultures mirrored their respective in vivo findings for cell proliferation and PLGF2 release. Human VECs, like rat cells, were unresponsive to siponimod treatment with no proliferative response and no release of PLGF2 at all tested concentrations. Hence, it is suggested that the human cells also reproduce a lack of in vivo response to siponimod. In conclusion, the molecular mechanisms leading to siponimod-induced HSA in mice are considered species specific and likely irrelevant to humans.


Assuntos
Azetidinas/efeitos adversos , Compostos de Benzil/efeitos adversos , Células Endoteliais/efeitos dos fármacos , Hemangiossarcoma/induzido quimicamente , Testes de Toxicidade Crônica/métodos , Administração Oral , Animais , Azetidinas/administração & dosagem , Compostos de Benzil/administração & dosagem , Células Cultivadas , Endotélio Vascular/citologia , Hemangiossarcoma/genética , Humanos , Masculino , Camundongos Endogâmicos , Fator de Crescimento Placentário/metabolismo , Ratos Sprague-Dawley , Ratos Wistar , Receptores de Lisoesfingolipídeo/antagonistas & inibidores , Receptores de Lisoesfingolipídeo/metabolismo , Especificidade da Espécie , Toxicocinética , Transcriptoma/efeitos dos fármacos
3.
Anal Chem ; 87(4): 2068-71, 2015 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-25607538

RESUMO

Hematocrit (Hct) is one of the most critical issues associated with the bioanalytical methods used for dried blood spot (DBS) sample analysis. Because Hct determines the viscosity of blood, it may affect the spreading of blood onto the filter paper. Hence, accurate quantitative data can only be obtained if the size of the paper filter extracted contains a fixed blood volume. We describe for the first time a microfluidic-based sampling procedure to enable accurate blood volume collection on commercially available DBS cards. The system allows the collection of a controlled volume of blood (e.g., 5 or 10 µL) within several seconds. Reproducibility of the sampling volume was examined in vivo on capillary blood by quantifying caffeine and paraxanthine on 5 different extracted DBS spots at two different time points and in vitro with a test compound, Mavoglurant, on 10 different spots at two Hct levels. Entire spots were extracted. In addition, the accuracy and precision (n = 3) data for the Mavoglurant quantitation in blood with Hct levels between 26% and 62% were evaluated. The interspot precision data were below 9.0%, which was equivalent to that of a manually spotted volume with a pipet. No Hct effect was observed in the quantitative results obtained for Hct levels from 26% to 62%. These data indicate that our microfluidic-based sampling procedure is accurate and precise and that the analysis of Mavoglurant is not affected by the Hct values. This provides a simple procedure for DBS sampling with a fixed volume of capillary blood, which could eliminate the recurrent Hct issue linked to DBS sample analysis.


Assuntos
Coleta de Amostras Sanguíneas/instrumentação , Teste em Amostras de Sangue Seco/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Desenho de Equipamento , Hematócrito , Humanos , Reprodutibilidade dos Testes
4.
Anal Bioanal Chem ; 405(1): 215-23, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23064707

RESUMO

A simple, sensitive, and selective liquid chromatography/tandem mass spectrometry method was validated for the identification and quantification of mavoglurant (AFQ056) in human plasma. The chromatographic separation was performed using a Cosmosil 5 C18 (150 × 4.6 mm, 5 µm) column at 40 ± 0.5 °C with a mobile phase consisting of acetic acid in water (0.1%, v/v)/methanol (10:90, v/v) with a flow rate of 1.0 mL/min followed by quantification with tandem mass spectrometry, operating with electrospray ionization in positive ion mode and applying multiple reaction monitoring. The validated method described in this paper presents high absolute recovery with precision and accuracy meeting the acceptance criteria. The method was precise and accurate for 2- and 10-fold dilution of samples. The method was validated using sodium heparin as specific anticoagulant, and the anticoagulant effect was tested by lithium heparin and K(3)EDTA. The method was successfully cross-validated between two bioanalytical sites. The method was specific for mavoglurant within the given criteria for acceptance (apparent peak area at the retention time of mavoglurant in zero samples was less than 20% compared with the mean peak area at LLOQ) in human plasma. The method was fully validated for the quantitative determination of mavoglurant in human plasma between the range of 2.00 and 2,500 ng/mL.


Assuntos
Cromatografia Líquida/métodos , Indóis/análise , Espectrometria de Massas em Tandem/métodos , Anticoagulantes/química , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Heparina/química , Humanos , Indóis/sangue , Íons , Modelos Químicos , Plasma/metabolismo , Receptor de Glutamato Metabotrópico 5 , Receptores de Glutamato Metabotrópico/metabolismo , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
5.
J Control Release ; 268: 314-322, 2017 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-29097303

RESUMO

Poor water solubility of drugs fuels complex formulations and jeopardizes patient access to medication. Simplifying these complexities we systematically synthesized a library of 36 sterically demanding counterions and mapped the pharmaceutical design space for amorphous ionic liquid strategies for Selurampanel, a poorly water soluble drug used against migraine. Patients would benefit from a rapid uptake after oral administration to alleviate migraine symptoms. Therefore, we probed the ionic liquids for the flux, supersaturation period and hygroscopicity leading to algorithms linking molecular counterion descriptors to predicted pharmaceutical outcome. By that, 30- or 800-fold improvements of the supersaturation period and fluxes were achieved as were immediate to sustained release profiles through structural counterions' optimization compared to the crystalline free acid of Selurampanel. Guided by ionic liquid structure, in vivo profiles ranged from rapid bioavailability and high maximal plasma concentrations to sustained patterns. In conclusion, the study outlined and predicted the accessible pharmaceutical design space of amorphous ionic liquid based and excipient-free formulations pointing to the enormous pharmaceutical potential of ionic liquid designs.


Assuntos
Líquidos Iônicos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada , Desenho de Fármacos , Liberação Controlada de Fármacos , Feminino , Humanos , Líquidos Iônicos/administração & dosagem , Líquidos Iônicos/química , Líquidos Iônicos/farmacocinética , Camundongos , Quinazolinonas/administração & dosagem , Quinazolinonas/química , Quinazolinonas/farmacocinética , Ratos Wistar
6.
Bioanalysis ; 7(4): 425-35, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25747762

RESUMO

AIM: An ultrafast, sensitive, selective and robust LDTD-APCI-MS/MS method was developed for the quantification of ceritinib in human plasma. RESULTS: Samples were protein precipitated using acetonitrile containing [(13)C6]-ceritinib as internal standard. The assay was validated over a concentration range from 5.00 to 1000 ng/ml. Intra- and inter-day precision and accuracy met acceptance from EMA and US FDA guidelines. The normalized recovery was 69%, whereas no carryover and matrix effects were observed. The method was applied to clinical samples and resultant data were consistent with the LC-ESI-MS/MS reference method. CONCLUSION: The new assay is suitable for ceritinib quantification in clinical trials, whereas the analysis time is significantly reduced to 10 s.


Assuntos
Análise Química do Sangue/métodos , Ensaios Clínicos como Assunto , Lasers , Espectrometria de Massas/métodos , Pirimidinas/sangue , Sulfonas/sangue , Análise Química do Sangue/instrumentação , Humanos , Limite de Detecção , Modelos Lineares , Espectrometria de Massas/instrumentação , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Fatores de Tempo
7.
Artigo em Inglês | MEDLINE | ID: mdl-22541169

RESUMO

A liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) method was validated for the quantification of Sotrastaurin (AEB071) and N-desmethyl-sotrastaurin in human blood. The validation of the analytical procedure was performed according to the latest Food and Drug Administration (FDA) "Guidance for Industry, Bioanalytical Method Validation". Chromatographic separation was performed using an RP C18 (50 mm × 4.6 mm, 5 µm) column at 40±3.0 °C with a mobile phase consisted of 2 mM ammonium acetate in water (pH 4.5):methanol:acetonitrile (25:15:60, v/v) of a flow rate of 1 mL/min followed by quantification with tandem mass spectrometer, operated in electrospray ionization (ESI) positive ion mode and applying multiple reaction monitoring (MRM). The validated method described in this paper presents high absolute recovery, with a sensitivity of 3.00 ng/mL as lower limit of quantitation using a sample volume of 300 µL, low inter-run bias and variability (for Sotrastaurin, -4.4 to 0.4% and 1.8 to 2.5% and for N-desmethyl-sotrastaurin, ranged from 1.6 to 2.3% and 2.7 to 3.9%, respectively) with a short runtime of 3.5 min. The method was validated using K3EDTA as specific anticoagulant and cross-validated using Li-Heparin and Na-Heparin. The method was specific for Sotrastaurin and N-desmethyl-sotrastaurin within the given criteria of acceptance (apparent peak area for Sotrastaurin and N-desmethyl-sotrastaurin in zero samples ≤ 20% of mean peak area at LLOQ) in human blood. The method was fully validated for the quantitative determination of Sotrastaurin and its metabolite N-desmethyl-sotrastaurin in human blood between the range of 3.00 ng/mL and 1200 ng/mL.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Pirróis/sangue , Quinazolinas/sangue , Cromatografia Líquida de Alta Pressão/normas , Estabilidade de Medicamentos , Humanos , Análise dos Mínimos Quadrados , Pirróis/química , Pirróis/metabolismo , Quinazolinas/química , Quinazolinas/metabolismo , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/métodos
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