Biodegradable polymers for controlled delivery of chemotherapy with and without radiation therapy in the monkey brain

Abstract
✓ Sustained drug delivery by biodegradable polymer devices can increase the therapeutic efficacy of drugs by producing high local tissue concentrations over extended periods of time. It has been shown previously that implantation of controlled-release polymers impregnated with the nitrosourea carmustine (BCNU) extended the period of survival in rats bearing the 9L glioma compared with similar rats treated with systemically administered BCNU. This study evaluated the effect on the monkey brain of interstitial delivery of BCNU by the biodegradable polyanhydride copolymer poly[bis(p-carboxyphenoxy)propane]anhydride (PCPP) and sebacic acid (SA) in a 20:80 formulation (PCPP:SA). The effect of combining interstitial BCNU with radiation therapy was also evaluated. Eighteen male cynomologus monkeys were randomly assigned to one of four groups: a control group; a group with implantation of empty polymer; a group with implantation of BCNU-loaded polymer; and a group with implantation of empty polymer in the right h...