• JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
 
  Bookmark and Share
 
 
Thèse de Doctorat
DOI
10.11606/T.60.2010.tde-09062010-122214
Document
Auteur
Nom complet
Carolina de Miranda Silva
Adresse Mail
Unité de l'USP
Domain de Connaissance
Date de Soutenance
Editeur
Ribeirão Preto, 2010
Directeur
Jury
Lanchote, Vera Lucia (Président)
Gaitani, Cristiane Masetto de
Guimaraes, Luiz Fernando Lopes
Coelho, Eduardo Barbosa
Donadi, Eduardo Antonio
Titre en portugais
Influência da função renal na farmacocinética dos enantiômeros da ciclofosfamida em pacientes portadores de nefrite lúpica
Mots-clés en portugais
Ciclofosfamida
Enantiômeros
Farmacocinética
Resumé en portugais
A farmacocinética dos enantiômeros da ciclofosfamida (CPA) foi avaliada em pacientes portadores de nefrite lúpica distribuídos em dois grupos de acordo com o clearance da creatinina: Grupo 1 90,6-144,6mL/min/1,73m2 e Grupo 2 42,8-76,4mL/min/1,73m2. Os pacientes foram tratados com doses de 0,75 a 1,3g de ciclofosfamida racêmica sob forma de infusão com duração de 2h e com 1mg de midazolam (MDZ) administrado via endovenosa para a avaliação da atividade in vivo do CYP3A. As concentrações plasmáticas dos enantiômeros da CPA e do MDZ foram avaliadas por LC-MS/MS. Os enantiômeros da CPA foram resolvidos na coluna Chiralcel OD-R, com fase móvel constituída por mistura de acetonitrila e água (75:25, v/v) adicionada de 0,2% de ácido fórmico. Os enantiômeros da CPA foram extraídos do plasma com recuperações maiores que 95% e o limite de quantificação obtido foi de 2,5ng de cada enantiômero da CPA/mL plasma. As seguintes diferenças (teste de Wilcoxon, p<0,05) foram observadas nos parâmetros farmacocinéticos entre os enantiômeros (S)-(-)-CPA e (R)-(+)-CPA para os pacientes do Grupo 1: AUC do tempo 0 ao infinito 152,41 vs 129,25g.h/mL; Cl 3,28 vs 3,89L/h; Vd 31,38 vs 29,74L e t1/2 6,79 vs 5,56h e para os pacientes do Grupo 2: AUC do tempo 0 ao infinito 167,20 vs 139,08g.h/mL; Cl 2,99 vs 3,59L/h e t1/2 6,15 vs 4,99h. Não foi observada diferença (teste de Mann-Whitney, p<0,05) nos parâmetros farmacocinéticos de ambos os enantiômeros entre os grupos 1 e 2. Não foi observada corrrelação entre o clearance do MDZ (2,92-16,40ml/min.kg) e o clearance de cada enantiômero da CPA. Concluindo, a farmacocinética da CPA é enantiosseletiva em pacientes portadores de nefrite lúpica com acúmulo plasmático do enantiômero (S)-(-)-CPA e a farmacocinética de ambos os enantiômeros da CPA não é alterada pela agravamento da função renal.
Titre en anglais
Influence of glomerular filtration rate on the pharmacokinetics of cyclophosphamide enantiomers in patients with lupus nephritis.
Mots-clés en anglais
cyclophosphamide
enantiomers
lupus nephritis
midazolam
pharmacokinetics
Resumé en anglais
The pharmacokinetics of cyclophosphamide (CYC) enantiomers was evaluated in patients with lupus nephritis distributed in two groups according to creatinine clearance; Group 1 - 90.6-144.6mL/min/1.73m2 and Group 2 - 42.8- 76.4mL/min/1.73m2. All patients were treated with 0.75 to 1.3g of racemic CYC as a 2-hour infusion and with 1mg intravenous midazolam as a drug marker. CYC enantiomers and midazolam concentrations in plasma were measured by LC-MS/MS. CYC enantiomers were separated on a Chiralcel OD-R column, with the mobile phase consisting of a mixture of acetonitrile and water (75:25, v/v) plus 0.2% formic acid. Recovery rates were higher than 95% and the quantification limit was 2.5ng/ml plasma for both enantiomers. The coefficients of variation and the relative errors obtained for the validation of intra- and interassay precision and accuracy were less than 10%. The following differences in the pharmacokinetic parameters (Wilcoxon test, p<0.05) were observed between the (S)-(-) and (R)-(+) enantiomers for Group 1 AUC from time 0 to infinity 152.41 vs 129.25g.h/mL, Cl 3.28 vs 3.89L/h, Vd 31.38 vs 29.74L and t1/2 6.79 vs 5.56h and for Group 2 AUC from time 0 to infinity 167.20 vs 139.08g.h/mL, Cl 2.99 vs 3.59 L/h and t1/2 6.15 vs 4.99 h. No differences (Mann-Whitney test, p<0.05) were observed between Groups 1 and 2 in the pharmacokinetics parameters of both enantiomers. No significant relationship was observed between midazolam clearance (2.92-16.40 ml/min.kg) and clearance of each CYC enantiomer. In conclusion, CYC kinetic disposition is enantioselective resulting in higher exposure of (S)-(-)-CYC in lupus nephritis patients and the pharmacokinetic parameters of both enantiomers are not altered by the worsening of renal condition.
 
AVERTISSEMENT - Regarde ce document est soumise à votre acceptation des conditions d'utilisation suivantes:
Ce document est uniquement à des fins privées pour la recherche et l'enseignement. Reproduction à des fins commerciales est interdite. Cette droits couvrent l'ensemble des données sur ce document ainsi que son contenu. Toute utilisation ou de copie de ce document, en totalité ou en partie, doit inclure le nom de l'auteur.
Date de Publication
2010-09-23
 
AVERTISSEMENT: Apprenez ce que sont des œvres dérivées cliquant ici.
Tous droits de la thèse/dissertation appartiennent aux auteurs
Centro de Informática de São Carlos
Bibliothèque Numérique de Thèses et Mémoires de l'USP. Copyright © 2001-2021. Tous droits réservés.