Target organ disposition and plasma pharmacokinetics of doxorubicin incorporated into albumin microspheres after intrarenal arterial administration.
Kerr DJ., Willmott N., McKillop JH., Cummings J., Lewi HJ., McArdle CS.
We synthesized doxorubicin (Adriamycin, Adria Laboratories, Columbus, OH)-loaded human albumin microspheres (containing approximately 1% doxorubicin w/w) between 15 and 20 micron in diameter. Intrarenal arterial administration of 99mTC-labeled microspheres demonstrated a high renal entrapment ratio (97% of recovered radioactivity). The pharmacokinetics and metabolism of doxorubicin are different when it is administered in microspherical form. Peak plasma levels are lower (16 ng/ml versus 135 ng/ml) compared with treatment by a doxorubicin solution. Histologic studies showed that the microspheres were trapped within capillaries and small arterioles in the renal vascular arcade. It is apparent that chemoembolization with doxorubicin-loaded microspheres significantly reduces systemic exposure to the antineoplastic agent, and maintains intrarenal drug levels.