DRUG KINETICS AND DRUG-RESISTANCE IN OPTIMAL CHEMOTHERAPY

A system of differential equations for the control of tumor cells grow th in a cycle nonspecific chemotherapy is presented. First-order drug kinetics and drug resistance are taken into account in a class of opti mal control problems. The results show that the strategy corresponding to the maximum rate of drug injection is optimal for the Malthusian m odel of cell growth (which is a relatively good model for the initial phase of tumor growth). For more general models of cell growth this st rategy proved to be suboptimal under certain conditions.