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Annals of Biomedical Engineering

, Volume 17, Issue 6, pp 633–646 | Cite as

Pharmacokinetic modeling of ethyl loflazepate (VictanR) and its main active metabolites

  • B. B. Ba
  • A. Iliadis
  • J. P. Cano
Article

Abstract

A simultaneous consideration of plasma and urine data of unchanged drug and active metabolites, taking into account the metabolic process of the precursor, is described. The maximum likelihood principle was used to estimate parameters. This methodology is highly efficient in determining the contribution of the two main and active metabolites in the pharmacological response of ethyl loflazepate. It also may serve in the search for optimum dosage regimens in clinical practice.

Keywords

Pharmacokinetic modeling Simultaneous treatment Active metabolites Plasma and urine data Ethyl loflazepate 

Nomenclature

EL

Ethyl loflazepate

L

Loflazepate

DCL

Descarboxyloflazepate

Do

administered amount of EL

Cp1

absorption compartment of EL

Cp2

central compartment of EL

Cp3

compartment of metabolite L

Cp4

compartment of metabolite DCL

Ka

absorption rate constant of EL

K1

rate constant of biotransformation of EL into L

K2

rate constant of biotransformation of L into DCL

K3

excretion rate constant of L

Kr

renal excretion rate constant of L

K4

elimination rate constant of DCL

V3

volume of distribution of L

V4

volume of distribution of DCL

α

contribution of L in the plasma concentration of the sum (L+DCL) (measured concentration)

β

contribution of DCL in the plasma concentration of (L+DCL)

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Copyright information

© Pergamon Press plc 1989

Authors and Affiliations

  • B. B. Ba
    • 1
  • A. Iliadis
    • 1
  • J. P. Cano
    • 1
  1. 1.Faculty of PharmacyINSERM U 278Marseilles, Cedex 05France

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