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1.
Bioanalysis ; 13(8): 609-619, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33847160

RESUMO

The 13th Global CRO Council (GCC) closed forum for bioanalysis was held in New Orleans, LA, USA on 5 April 2019. This GCC meeting was organized to discuss the contents of the 2019 ICH M10 Bioanalytical Method Validation Draft Guideline published in February 2019 and consolidate the feedback of the GCC members. While ICH M10 will cover requirements for reference standards, one of the biggest challenges facing the CRO community is the lack of consistency and completeness of Certificates of Analysis for reference standards used in regulated bioanalysis. Similar challenges exist with critical reagents (e.g., capture and detection antibodies) used for assays supporting biologics. The recommendations provided in this publication are the minimum requirements for the content that GCC members believe should be included in Certificates of Analysis for reference standards obtained from commercial vendors, sponsors and compendial suppliers, for use in regulated bioanalytical studies. In addition, recommendations for internal standards, metabolites and critical reagents are discussed.


Assuntos
Anticorpos/análise , Bioensaio/normas , Humanos , Padrões de Referência
3.
Am J Ther ; 22(5): e130-40, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25853236

RESUMO

Combining different classes of antihypertensives is more effective for reducing blood pressure (BP) than increasing the dose of monotherapies. The aims of this phase I study were to investigate pharmacokinetic and pharmacodynamic interactions between nebivolol, a vasodilatory ß1-selective blocker, and valsartan, an angiotensin II receptor blocker, and to assess safety and tolerability of the combination. This was a single-center, randomized, open-label, multiple-dose, 3-way crossover trial in 30 healthy adults aged 18-45 years. Participants were randomized into 1 of 6 treatment sequences (1:1:1:1:1:1) consisting of three 7-day treatment periods followed by a 7-day washout. Once-daily oral treatments comprised nebivolol (20 mg), valsartan (320 mg), and nebivolol-valsartan combination (20/320 mg). Outcomes included AUC0-τ,ss, Cmax,ss, Tmax,ss, changes in BP, pulse rate, plasma angiotensin II, plasma renin activity, 24-hour urinary aldosterone, and adverse events. Steady-state pharmacokinetic interactions were observed but deemed not clinically significant. Systolic and diastolic BP reduction was significantly greater with nebivolol-valsartan combination than with either monotherapy. The mean pulse rate associated with nebivolol and nebivolol-valsartan treatments was consistently lower than that associated with valsartan monotherapy. A sharp increase in mean day 7 plasma renin activity and plasma angiotensin II that occurred in valsartan-treated participants was significantly attenuated with concomitant nebivolol administration. Mean 24-hour urine aldosterone at day 7 was substantially decreased after combined treatment, as compared with either monotherapy. All treatments were safe and well tolerated. In conclusion, nebivolol and valsartan coadministration led to greater reductions in BP compared with either monotherapy; nebivolol and valsartan lower BP through complementary mechanisms.


Assuntos
Anti-Hipertensivos/farmacologia , Nebivolol/farmacologia , Valsartana/farmacologia , Adolescente , Adulto , Aldosterona/urina , Angiotensina II/sangue , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/farmacocinética , Área Sob a Curva , Estudos Cross-Over , Quimioterapia Combinada , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Nebivolol/administração & dosagem , Nebivolol/efeitos adversos , Nebivolol/farmacocinética , Projetos Piloto , Pulso Arterial , Renina/sangue , Valsartana/administração & dosagem , Valsartana/efeitos adversos , Valsartana/farmacocinética , Adulto Jovem
4.
Bioanalysis ; 6(22): 3039-49, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25496256

RESUMO

The 2014 8th Workshop on Recent Issues in Bioanalysis (8th WRIB), a 5-day full immersion in the evolving field of bioanalysis, took place in Universal City, California, USA. Close to 500 professionals from pharmaceutical and biopharmaceutical companies, contract research organizations and regulatory agencies worldwide convened to share, review, discuss and agree on approaches to address current issues of interest in bioanalysis. The topics covered included both small and large molecules, and involved LCMS, hybrid LBA/LCMS, LBA approaches and immunogenicity. From the prolific discussions held during the workshop, specific recommendations are presented in this 2014 White Paper. As with the previous years' editions, this paper acts as a practical tool to help the bioanalytical community continue advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2014 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 1) covers the recommendations for small molecule bioanalysis using LCMS. Part 2 (Hybrid LBA/LCMS, Electronic Laboratory Notebook and Regulatory Agencies' input) and Part 3 (Large molecules bioanalysis using LBA and Immunogenicity) will be published in the upcoming issues of Bioanalysis.


Assuntos
Bioensaio , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos
5.
Antimicrob Agents Chemother ; 52(10): 3478-83, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18644951

RESUMO

In this open-label, single-center study, eight healthy men each received a single 500-mg dose of [(14)C]doripenem, containing 50 microCi of [(14)C]doripenem, administered as a 1-h intravenous infusion. The concentrations of unchanged doripenem and its primary metabolite (doripenem-M-1) resulting from beta-lactam ring opening were measured in plasma and urine by a validated liquid chromatography method coupled to a tandem mass spectrometry assay. Total radioactivity was measured in blood, plasma, urine, and feces by liquid scintillation counting. Further metabolite profiling was conducted on urine samples using liquid chromatography coupled to radiochemical detection and high-resolution mass spectrometry. Unchanged doripenem and doripenem-M-1 accounted for means of 80.7% and 12.7% of the area under the plasma total-radioactivity-versus-time curve (area under the concentration-time curve extrapolated to infinity) and exhibited elimination half-lives of 1.1 and 2.5 h, respectively. Total clearance of doripenem was 16 liters/h, and renal clearance was 12.5 liters/h. At 7 days after the single dose, 95.3% of total doripenem-related radioactivity was recovered in urine and 0.72% in feces. A total mean of 97.2% of the administered dose was excreted in the urine as unchanged doripenem (78.7% +/- 5.7%) and doripenem-M-1 (18.5% +/- 2.6%). Most of the urinary recovery occurred within 4 h of dosing. Three additional minor metabolites were identified in urine: the glycine and taurine conjugates of doripenem-M-1 and oxidized doripenem-M-1. These results show that doripenem is predominantly eliminated in urine as unchanged drug, with only a fraction metabolized to doripenem-M-1 and other minor metabolites.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Carbapenêmicos/administração & dosagem , Carbapenêmicos/farmacocinética , Adolescente , Adulto , Antibacterianos/efeitos adversos , Antibacterianos/metabolismo , Carbapenêmicos/efeitos adversos , Carbapenêmicos/metabolismo , Radioisótopos de Carbono , Cromatografia Líquida , Estudos de Coortes , Doripenem , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Segurança , Espectrometria de Massas em Tandem
6.
Artigo em Inglês | MEDLINE | ID: mdl-14751795

RESUMO

Glipizide and rosiglitazone are widely used to treat Type 2 diabetes. In order to investigate drug-drug protein binding interaction between glipizide and rosiglitazone, a method was developed and validated for simultaneously determining the free (unbound) fraction of glipizide and rosiglitazone in plasma employing equilibrium dialysis for the separation of free drug and liquid chromatography-tandem mass spectrometry (LC-MS/MS) for quantitation. Post-dialysis human plasma or buffer samples of 0.2 ml were extracted using a liquid-liquid extraction procedure and analyzed by a high performance liquid chromatography electrospray tandem mass spectrometer system. The compounds were eluted isocratically on a Zorbax SB-Phenyl column, ionized using an atmospheric pressure electrospray ionization source and analyzed in positive ion mode with multiple reaction monitoring. The ion transitions monitored were m/z 446-->321 for glipizide, m/z 358-->135 for rosiglitazone, and m/z 271-->155 for tolbutamide (internal standard, IS). The chromatographic run time was 5 min per injection, with retention times of 2.3, 3.4 and 2.3 min for glipizide, rosiglitazone and IS, respectively. The calibration curves of glipizide and rosiglitazone were over the range of 1-2000 ng/ml (r(2)>0.9969) in the combined matrix of human plasma and isotonic sodium phosphate buffer (1:1, v/v). The inter-assay precision and accuracy of the quality control samples were <10.9% of coefficient of variability and >93.5% and 94.5% of nominal concentration for glipizide and rosiglitazone, respectively. The lower limit of quantitation of both glipizide and rosiglitazone was 1.0 ng/ml. Both glipizide and rosiglitazone bound to plasma protein extensively (>99% bound). Glipizide and rosiglitazone free fraction averaged 0.678+/-0.071 and 0.389+/-0.061%, respectively, at plasma concentration of 1000 ng/ml. This developed method proves reproducible and sensitive and its application to clinical samples is also reported.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Diálise , Glipizida/sangue , Hipoglicemiantes/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Tiazolidinedionas/sangue , Estabilidade de Medicamentos , Humanos , Controle de Qualidade , Reprodutibilidade dos Testes , Rosiglitazona , Sensibilidade e Especificidade
7.
J Pharm Biomed Anal ; 33(1): 101-8, 2003 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-12946536

RESUMO

A liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous determination of pioglitazone (PIO) and its two metabolites: M-III (keto-derivative) and M-IV (hydroxy-derivative) in human plasma. Human plasma samples of 0.2 ml were extracted by a single step liquid-liquid extraction procedure and analyzed using a high performance liquid chromatography (HPLC) electrospray tandem mass spectrometer system. The compounds were eluted isocratically on a C-18 column, ionized using a positive ion atmospheric pressure electrospray ionization source and analyzed using multiple reaction monitoring mode. The ion transitions monitored were m/z 357-->134 for PIO, m/z 371-->148 for M-III, m/z 373-->150 for M-IV and m/z 413-->178 for the internal standard. The chromatographic run time was 2.5 min per injection, with retention times of 1.45, 1.02 and 0.95 min for PIO, M-III and M-IV, respectively. The calibration curves of pioglitazone, M-III and M-IV were well fit over the range of 0.5-2000 ng/ml (r(2)>0.998759) by using a weighted (1/x(2)) quadratic regression. The inter-day precisions of the quality control samples (QCs) were

Assuntos
Hipoglicemiantes/sangue , Tiazolidinedionas/sangue , Biotransformação , Calibragem , Cromatografia Líquida de Alta Pressão , Humanos , Indicadores e Reagentes , Espectrometria de Massas , Pioglitazona , Controle de Qualidade , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta
8.
J Clin Pharmacol ; 43(4): 406-13, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12723461

RESUMO

The objective of this study was to investigate the pharmacokinetics and ex vivo pharmacodynamics of increasing doses of RWJ 67657, along with the effect of food at one dose level in a first-in-human (FIH) study. This was a placebo-controlled, double-blind, randomized trial in healthy male subjects. Subjects received increasing doses of RWJ 67657 or placebo as a single oral dose (0.25-30 mg/kg) under fasting conditions. The effect of food was investigated for the 10-mg/kg dose. Plasma concentrations of RWJ 67657 were measured over a period of 48 hours using a validated LC-MS/MS method. To evaluate the pharmacodynamics of RWJ 67657, inhibition of cytokine production was monitored from exvivo-stimulated polymorphonuclear blood cells (PBMCs). Pharmacokinetic/pharmacodynamic modeling was used to characterize the inhibitory activity of RWJ 67657. RWJ 67657 was rapidly absorbed (mean tmax = 0.6-2.5 h). The pharmacokinetics of RWJ 67657 appear to be nonlinear with respect to single-dose administration of the investigative formulation. Coadministration of food did not have a significant effect on half-life or time to peak concentration (tmax) but decreased the exposure. Mean Cmax values in the presence of food were almost 50% lower than during fasting (542 vs. 1283 ng/mL), and the AUC decreased from 2832 to 1904 ng.h/mL with food. RWJ 67657 inhibited TNF-alpha, IL-8, and IL-6 in a concentration-dependent manner with mean IC50 values of 0.18 microM, 0.04 microM, and 0.43 microM, respectively. At 20 mg/kg, the median inhibition was greater than 85%. There were no significant adverse effects associated with single doses of this drug. This study demonstrates that RWJ 67657 has acceptable safety and pharmacokinetics to warrant further investigation in a repeat-dose setting. In addition, the early determination of effect on biomarkers suggests potential efficacy in diseases mediated by proinflammatory and inflammatory cytokines.


Assuntos
Imidazóis/farmacocinética , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Piridinas/farmacocinética , Administração Oral , Adulto , Área Sob a Curva , Biomarcadores , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Interações Alimento-Droga , Cromatografia Gasosa-Espectrometria de Massas , Meia-Vida , Humanos , Concentração de Íons de Hidrogênio , Imidazóis/administração & dosagem , Imidazóis/farmacologia , Masculino , Piridinas/administração & dosagem , Piridinas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno
9.
Antimicrob Agents Chemother ; 46(4): 996-1004, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11897581

RESUMO

Several cyclopentane inhibitors of influenza virus neuraminidase that have inhibitory activities in tissue culture similar to those of zanamivir and oseltamivir have recently been described. These new inhibitors have been examined for efficacy against a virulent H3N2 influenza virus when administered orally to infected ferrets. Preliminary studies indicated that oral administration of BCX-1923, BCX-1827, or BCX-1812 (RWJ-270201) at a dose of 5 or 25 mg/kg of body weight was active in ferrets in reducing respiratory and constitutional signs and symptoms, but these antivirals affected virus titers in the upper and lower respiratory tracts only marginally. Of the three compounds, BCX-1812 seemed to be the most efficacious and was examined further at higher doses of 30 and 100 mg/kg. These doses significantly reduced peak virus titers in nasal washes and total virus shedding as measured by areas under the curve. Virus titers in lung homogenates were also reduced compared to those in controls, but the difference was not statistically significant. As was observed with BCX-1812 at lower doses, the nasal inflammatory cellular response, fever, and nasal signs were reduced while ferret activity was not, with activity remaining similar to uninfected animals.


Assuntos
Antivirais/farmacologia , Ciclopentanos/farmacologia , Inibidores Enzimáticos/farmacologia , Furões/fisiologia , Vírus da Influenza A/efeitos dos fármacos , Neuraminidase/antagonistas & inibidores , Infecções por Orthomyxoviridae/tratamento farmacológico , Acetamidas/farmacologia , Ácidos Carbocíclicos , Animais , Antivirais/farmacocinética , Área Sob a Curva , Temperatura Corporal , Contagem de Células , Ciclopentanos/farmacocinética , Inibidores Enzimáticos/farmacocinética , Guanidinas , Meia-Vida , Testes de Inibição da Hemaglutinação , Pulmão/microbiologia , Masculino , Cavidade Nasal/citologia , Cavidade Nasal/virologia , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , Oseltamivir
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