Return to search

Hepatic Disposition of Drugs and the Utility of Mechanistic Modelling and Simulation

The elimination of drugs from the body is in many cases performed by the liver. Much could be gained if an accurate prediction of this process could be made early in the development of new drugs. However, for the elimination to occur, the drug molecule needs first to get inside the liver cell. Disposition is the expression used to encapsulate both elimination and distribution. This thesis presents novel approaches and models based on simple in vitro systems for the investigation of processes involved in the hepatic drug disposition. An approach to the estimation of enzyme kinetics based on substrate depletion data from cell fractions was thoroughly evaluated through experiments and simulations. The results that it provided were confirmed to be accurate and robust. In addition, a new experimental setup suitable for a screening environment, i.e., for a reduced number of samples, was generated through optimal experimental design. The optimization suggested that sampling at late time points over a wide range of concentration was the most advantageous. A model, based on data from primary hepatocytes in suspension, for the investigation of cellular disposition of metabolized drugs was developed. Information on the relative importance of metabolism and membrane protein related distribution was obtained by analysis of changes in the kinetics by specific inhibition of the various processes. The model was evaluated by comparing the results to those obtained from an in vivo study analyzed with an especially constructed mechanistic PBPK model. These investigations showed that the suggested model produced good predictions of the relative importance of metabolism and carrier mediated membrane transport for hepatic disposition. In conclusion, new approaches for the investigation of processes involved in hepatic disposition were developed. These methods were shown to be robust and increased the output of information from already commonly implemented in vitro systems.

Identiferoai:union.ndltd.org:UPSALLA1/oai:DiVA.org:uu-132571
Date January 2010
CreatorsSjögren, Erik
PublisherUppsala universitet, Institutionen för farmaci, Uppsala : Acta Universitatis Upsaliensis
Source SetsDiVA Archive at Upsalla University
LanguageEnglish
Detected LanguageEnglish
TypeDoctoral thesis, comprehensive summary, info:eu-repo/semantics/doctoralThesis, text
Formatapplication/pdf
Rightsinfo:eu-repo/semantics/openAccess
RelationDigital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Pharmacy, 1651-6192 ; 132

Page generated in 0.0022 seconds