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


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.


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



Ethyl loflazepate






administered amount of EL


absorption compartment of EL


central compartment of EL


compartment of metabolite L


compartment of metabolite DCL


absorption rate constant of EL


rate constant of biotransformation of EL into L


rate constant of biotransformation of L into DCL


excretion rate constant of L


renal excretion rate constant of L


elimination rate constant of DCL


volume of distribution of L


volume of distribution of DCL


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


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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