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1.
Clin Exp Rheumatol ; 39(5): 931-937, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33253089

RESUMO

OBJECTIVES: Peripheral and axial manifestations of psoriatic arthritis (PsA) can lead to irreversible structural damage and chronic disability. Our objective was to explore predictors of radiographic progression and to increase our understanding of treatment effects in subgroups of patients with different rates of structural damage progression. METHODS: We analysed data from two large Phase-3 trials of secukinumab in PsA patients, FUTURE-1 (NCT01392326, n=606) and FUTURE-5 (NCT02404350, n=996), where different posologies ranging from 75 mg to 300 mg were used. We applied a longitudinal Bayesian mixture model with random effects to account for the variability in the repeated radiographic assessments. "Fast progressors" were defined post hoc as patients with a 50% model-estimated probability to progress at least 0.5 mTSS/year faster than an average patient. RESULTS: Higher baseline inflammation and higher body weight were identified as significant predictors of radiographic progression (multivariate model). Model-estimated structural damage progression in an average patient treated with secukinumab 150 mg subcutaneous (s.c.) was slower (0.04 mTSS/year; 95% CI -0.28, 0.34) compared to a patient treated with placebo (0.94 mTSS/year; 95% CI 0.45, 1.45). According to the model, the subgroup of "fast progressors" (hsCRP ≥26 mg/L, body weigth ≥94 kg, inadequate response to prior anti-TNF-alpha, structural damage ≥42 mTSS) treated with secukinumab 150 mg s.c. progressed at 0.56 mTSS/year (95% CI 0.02, 1.09) and 1.46 mTSS/year (95% CI 0.81, 2.11) when treated with placebo. CONCLUSIONS: Greater systemic inflammation and higher body weight at baseline were identified as significant predictors of progression. Even patients with fast radiographic progression could experience a beneficial effect with secukinumab that holds promise to prevent further mobility loss.


Assuntos
Antirreumáticos , Artrite Psoriásica , Anticorpos Monoclonais Humanizados , Antirreumáticos/efeitos adversos , Artrite Psoriásica/diagnóstico por imagem , Artrite Psoriásica/tratamento farmacológico , Teorema de Bayes , Progressão da Doença , Método Duplo-Cego , Humanos , Resultado do Tratamento , Inibidores do Fator de Necrose Tumoral
2.
Drug Discov Today ; 23(4): 788-801, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29337204

RESUMO

Demand for healthcare services is unprecedented. Society is struggling to afford the cost. Pricing of biopharmaceutical products is under scrutiny, especially by payers and Health Technology Assessment agencies. As we discuss here, rapidly advancing technologies, such as Real-World Data (RWD), are being utilized to increase understanding of disease. RWD, when captured and analyzed, produces the Real-World Evidence (RWE) that underpins the economic case for innovative medicines. Furthermore, RWD can inform the understanding of disease, help identify new therapeutic intervention points, and improve the efficiency of research and development (R&D), especially clinical trials. Pursuing precompetitive collaborations to define shared requirements for the use of RWD would equip service-providers with the specifications needed to implement cloud-based solutions for RWD acquisition, management and analysis. Only this approach would deliver cost-effective solutions to an industry-wide problem.


Assuntos
Biofarmácia/economia , Animais , Ensaios Clínicos como Assunto/economia , Análise Custo-Benefício/economia , Humanos , Pesquisa/economia
3.
J Pharmacol Exp Ther ; 360(2): 356-367, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27934627

RESUMO

Sphingosine 1-phosphate (S1P) receptor agonists are associated with cardiovascular effects in humans. This study aims to develop a systems pharmacology model to identify the site of action (i.e., primary hemodynamic response variable) of S1P receptor agonists, and to predict, in a quantitative manner, the cardiovascular effects of novel S1P receptor agonists in vivo. The cardiovascular effects of once-daily fingolimod (0, 0.1, 0.3, 1, 3, and 10 mg/kg) and siponimod (3 and 15 mg/kg) were continuously recorded in spontaneously hypertensive rats and Wistar-Kyoto rats. The results were analyzed using a recently developed systems cardiovascular pharmacology model, i.e. the CVS model; total peripheral resistance and heart rate were identified as the site of action for fingolimod. Next, the CVS model was interfaced with an S1P agonist pharmacokinetic-pharmacodynamic (PKPD) model. This combined model adequately predicted, in a quantitative manner, the cardiovascular effects of siponimod using in vitro binding assays. In conclusion, the combined CVS and S1P agonist PKPD model adequately describes the hemodynamic effects of S1P receptor agonists in rats and constitutes a basis for the prediction, in a strictly quantitative manner, of the cardiovascular effects of novel S1P receptor agonists.


Assuntos
Azetidinas/farmacologia , Compostos de Benzil/farmacologia , Sistema Cardiovascular/efeitos dos fármacos , Cloridrato de Fingolimode/farmacologia , Modelos Biológicos , Animais , Azetidinas/farmacocinética , Compostos de Benzil/farmacocinética , Biologia Computacional , Cloridrato de Fingolimode/farmacocinética , Frequência Cardíaca/efeitos dos fármacos , Masculino , Ratos , Receptores de Lisoesfingolipídeo/metabolismo
4.
Drug Metab Dispos ; 42(9): 1367-78, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24965813

RESUMO

A complicating factor in the translational pharmacology of sphingosine 1-phosphate agonists is that they exert their pharmacological effect through their respective phosphate metabolites, which are formed by the enzyme sphingosine kinase (S1PHK). In this investigation, we present a semimechanistic pharmacokinetic model for the interconversion of S1PHK substrates and their respective phosphates in rats and humans with the aim of investigating whether characterization of the rate of phosphorylation in blood platelets constitutes a basis for interspecies scaling using fingolimod as a model compound. Data on the time course of fingolimod and fingolimod-phosphate (fingolimod-P) blood concentrations after intravenous and oral administration of fingolimod and/or fingolimod-P in rats and after oral administration of fingolimod in doses of 0.5, 1.25, and 5 mg once daily in healthy volunteers were analyzed in conjunction with data on the ex vivo interconversion and blood-plasma distribution in rat and human blood, respectively. Integrating the data from the ex vivo and in vivo studies enabled simulation of fingolimod and fingolimod-P concentrations in plasma rather than blood, which are more relevant for characterizing drug effects. Large interspecies differences in the rate of phosphorylation between rats and humans were quantified. In human, phosphorylation of fingolimod in the platelets was four times slower compared with rat, whereas the dephosphorylation rates were comparable in both species. This partly explained the 10-12-fold overprediction of fingolimod-P exposure in human when applying a dose-by-factor approach on the developed rat model. Additionally, differences in presystemic phosphorylation should also be taken into account.


Assuntos
Fosforilação/efeitos dos fármacos , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Propilenoglicóis/administração & dosagem , Propilenoglicóis/farmacocinética , Esfingosina/análogos & derivados , Administração Intravenosa , Administração Oral , Animais , Plaquetas/metabolismo , Método Duplo-Cego , Cloridrato de Fingolimode , Humanos , Lisofosfolipídeos/metabolismo , Masculino , Fosfatos/metabolismo , Ensaios Clínicos Controlados Aleatórios como Assunto , Ratos , Ratos Endogâmicos Lew , Ratos Sprague-Dawley , Esfingosina/administração & dosagem , Esfingosina/metabolismo , Esfingosina/farmacocinética
5.
J Pharm Sci ; 92(10): 1990-2007, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14502539

RESUMO

The objective of this study was to use in synergy physiologically based and empirical approaches to estimate the drug-specific input parameters of PBPK models of disposition to simulate the plasma concentration-time profile of epiroprim in human. The estimated input parameters were the tissue:plasma partition coefficients (Pt:p) for distribution and the blood clearance (CL) for the in vivo conditions. Epiroprim represents a challenge for such methods, because it shows large interspecies differences in its pharmacokinetic properties. Two approaches were used to predict the human Pt:p values: the tissue composition model (TCM) and the "Arundel approach" based on the volume of distribution at steady state (Vdss) determined in vivo in the rat. CL in human was predicted by (1) conventional allometric scaling of in vivo animal clearances (CAS), (2) physiologically based direct scaling up of in vitro hepatocyte data (DSU), and (3) allometric scaling of animal intrinsic in vivo blood CL normalized by the ratios of animal:human intrinsic clearances determined in vitro with hepatocytes (NAS). The performance of prediction was assessed by comparing separately the above pharmacokinetic parameters (Vdss estimated from the Pt:p values and blood CL) with the corresponding in vivo data obtained from the plasma kinetic profiles. These input parameters were used in PBPK models, and the resulting plasma concentration-time profiles of epiroprim were compared with those observed in rat and human. Previously to the construction of the human PBPK model, a model for the rat was also developed to gain more confidence on the model structure and assumptions. Overall, using the TCM and the NAS for the parameterization of the distribution and clearance, respectively, the PBPK model gave the more accurate predictions of epiroprim's disposition in human. This study represents therefore an attractive approach, which may potentially help the clinical candidate selection.


Assuntos
Trimetoprima/análogos & derivados , Trimetoprima/farmacocinética , Animais , Peso Corporal , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Cães , Hepatócitos/metabolismo , Humanos , Macaca , Masculino , Camundongos , Modelos Biológicos , Especificidade da Espécie , Fatores de Tempo , Distribuição Tecidual
6.
Biochem Pharmacol ; 64(11): 1637-50, 2002 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-12429353

RESUMO

The influence of the isolation procedure of hepatocytes, extracellular matrix (ECM) configuration and incubation medium supplementation by dexamethasone (DEX) on the cell morphology and on the gene expression of membrane transporters was examined in rat hepatocytes. The mRNA levels were determined using oligonucleotide microarrays, in liver, in suspension and in primary culture in monolayer (CPC), and in collagen gels sandwich (SPC) in absence and presence of DEX (100 and 1000 nM). The results indicated pronounced morphological differences between CPC and SPC in response to DEX demonstrating that the hepatocytes re-formed, as in vivo, multicellular arrays with extensive bile canalicular network only in SPC in presence of DEX. The mRNA levels of membrane transporters were not affected significantly during isolation procedure. However, plating hepatocytes in CPC resulted in a decrease of major basolateral transporters mRNA level whereas mRNA levels of mdr1b and mrp3 were increased (>100-fold). Similar observations were made in SPC in the absence of DEX demonstrating that the ECM configuration alone did not play a critical role in the regulation of membrane transporters. However, adding DEX to the incubation medium in SPC resulted in an up-regulation of mdr2, oatp2 and mrp2 in a concentration-dependent way for the two latter genes, whereas mdr1b and mrp3 expression were maintained to their baseline liver levels. These data suggested therefore that the combination of ECM and DEX supplementation is essential for the formation of the bile canalicular network and is a determinant factor in the regulation of membrane transporters in cultured rat hepatocytes.


Assuntos
Dexametasona/farmacologia , Matriz Extracelular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Proteínas de Membrana Transportadoras/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/biossíntese , Transportadores de Cassetes de Ligação de ATP/biossíntese , Animais , Tamanho Celular/efeitos dos fármacos , Células Cultivadas , Quimiocinas CC/biossíntese , Hepatócitos/fisiologia , Proteínas Inflamatórias de Macrófagos/biossíntese , Proteínas de Membrana Transportadoras/biossíntese , Ratos
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