Cytotoxic-loaded albumin microspheres: a novel approach to regional chemotherapy.

Adriamycin-loaded albumin microspheres (15-40 micron diameter) incorporating 1 per cent by weight of Adriamycin were prepared by cross linking albumin with glutaraldehyde. After systemic administration in rats, the microspheres were trapped in the pulmonary capillary bed, biodegradation occurring over 48 h. After selective intrarenal arterial injection of 99mTc-labelled albumin microspheres in rabbits, 97 per cent of the injected microspheres were trapped within the kidney; less than 1 per cent were found in the contralateral kidney, lungs and liver. Similar results were obtained after selective intrahepatic arterial injection. The selective injection of cytotoxic-loaded microspheres may provide a reliable method of administering high concentrations of cytotoxic drug to a target organ without producing high serum levels; this technique may have a role in the management of solid tumours.