PHARMACOKINETICS OF PLATINUM IN CANCER-PATIENTS FOLLOWING INTRAVENOUS-INFUSION OF CIS-DIAMMINE(GLYCOLATO) PLATINUM, 254-S

The pharmacokinetics of platinum in cancer patients were examined foll owing an intravenous infusion of cis-diammine(glycolato) platinum, 254 -S. The plasma concentrations of total platinum, which decreased biexp onentially after the infusion, were proportional to the dose over the range of 10 to 120 mg/m(2), suggesting linearity of the pharmacokineti cs. The plasma concentrations of ultrafilterable platinum were similar to those of total platinum and there was little difference in the pha rmacokinetic parameters between total platinum and ultrafilterable pla tinum. These findings show that almost all of the platinum derivative is unbound, which is thought to be the active form, in plasma after ad ministration of 254-S. Platinum was eliminated from blood faster, when given as 254-S rather, than as cisplatin because of the low protein b inding. The urinary recovery within 24 hours was about half of the dos e, suggesting that platinum given as 254-S was distributed to various tissues and organs in an active form.