Pharmacokinetics of 1-β- d-arabinofuranosylcytosine (Ara-C) deamination in several species

The pharmacokinetics of 1-β- d-arabinofuranosylcytosine (Ara-C) and 1-β- d-arabinofuranosyluracil (Ara-U) are related to enzyme kinetics in vitro in mice, monkeys, dogs and humans by means of a mathematical model. The model is physiologic and permits the incorporation of chemical reactions in appropriate anatomic sites with kinetic characteristics of their local environment. A lean tissue compartment plays an important role as a reservoir. The kidney clearance of Ara-C exhibits essentially the same variation with body weight as inulin.