DOSE EXPRESSION OF ANTICANCER DRUGS

Anticancer drugs dosage are currently adjusted to body surface area. T his measure is supposed to be the best morphometric parameter to adjus t anticancer drug doses. However, dose adjustment to body surface area has not historically been rigorously demonstrated. We propose a metho d to objectively teat this parameter utility. The statistical justific ation of drug adjustment to body surface area can use mathematical equ ations to be expressed. We can demonstrate that body surface area and plasmatic total clearance of a drug should be correlated to adjust dos e anticancer drug to body surface area. When we test the hypothesis of body surface area and plasmatic clearance correlation for cytarabine and adriamycin we did not find any significant correlation. For these anticancer drugs, dose adjustment to body surface area increase their pharmacokinetic and efficiency variabilities. The concept of dose-inte nsity is probably the best justification of individual dose adjustment from plasmatic drug samples, and from pharmacokinetic and pharmacodyn amic studies. The determination of the ''maximal tolerable exposition' ' and of the ''minimal effective exposition'' should reduce the overex pression of toxic risks and avoid the ineffective underexpositions. Ho wever, it is difficult to precisely define these two expositions and t o research the most relevant pharmacokinetic parameters to their measu re. Area under curve appears to be most appropriate expression.