Systemic blood levels after intra-arterial administration of microencapsulated mitomycin C in cancer patients.

Systemic delivery of mitomycin C (MMC) was studied in 6 patients administered microencapsulated MMC (MMC-mc) by an intra-arterial route (IA): 3 IA liver infusions, 3 IA pelvic infusions. Pharmacokinetic data revealed a lower blood MMC availability (peak plasma levels, AUC 0-4 hours) for the pelvis than for the liver; this was attributed to differences in the blood flow infusion rates at these two sites of administration. Direct comparison of systemic MMC exposure was possible for one patient, who received both IA liver MMC (10 mg in standard form, which served as the control) and IA liver MMC-mc (20 mg the day after). The 65% reduction in MMC-mc bioavailability observed for this patient indicates a quantitative local improvement in exposure to the drug and correlates well with the low incidence of systemic side effects noted in preliminary clinical studies.