ABSTRACT
Within the past four decades, there has been signicant progress in PK/TK modeling and it will become progressively more complex and sophisticated. However, a link between experimental sciences and predictive modeling must exist in order to maintain a rm base of reality. Lord Bertrand Russell, the 20th century philosopher and mathematician (1872-1970), in his A History of Western Philosophy, wrote:
One traditional approach in PK/TK modeling, known as compartmental analysis, is to develop the model based on concentration-time curves of xenobiotics and/or their metabolite(s) or other relevant biological variables in the body. Thus, the data dene the model, and the model is then tested to see how closely it agrees with the observed data, and hence the model describes the data. This type of modeling is used to summarize the data, and to predict the behavior of a compound in the system as a function of biological processes. A different conventional approach in PK/TK modeling is to rely on the anatomical and physiological regions of the body comprising of all relevant tissues and organs of disposition connected via the vascular system. There are other approaches in PK/TK modeling such as stochastic or neuronal network models that are based on different fundamentals than the traditional modeling. The following sections describe the popular approaches in PK/TK modeling.
