Nude mice were challenged with human U-87 MG
glioblastoma tumors to assess the efficacy of different
cytostatics and different application protocols. While the intraperitoneal application of
BCNU solutions (3 times 20 mg
BCNU/kg) had no effect on
tumor growth, the application of
polymer matrices made of a physical mixture of poly(1,3-bis[carboxyphenoxpropane]-co-
sebacic acid) 20:80 with
poly(D,L-lactic-co-glycolic acid) loaded with 0.25 mg
BCNU, slowed down the growth of
tumors significantly. When the animals were treated with implants carrying 0.25 mg
BCNU they responded to the treatment whether the
tumor had been inoculated recently (9 days ago) or whether it was fully established (after 20 days). After its sensitivity was proven, the xenograft model was used to further investigate the efficacy of anticancer drugs and some treatment regimens using
polymer implants. Thus the
tumor model allowed to discriminate between the efficacy of different doses of
BCNU. Only implants loaded with 0.75 or 1 mg of
BCNU led to a substantial suppression of
tumor growth over approximately 2 months. While
BCNU was only able to suppress the growth of the
tumor, the combination of
BCNU with
paclitaxel led to a complete remission in some animals. These preliminary results suggest that combinations of
cytostatics might improve local
chemotherapy of
malignant glioma substantially. Based on our data it will be worthwhile to investigate implants that release drugs such as
BCNU and
paclitaxel closer. Amongst other factors we will try to elucidate the effect of repetitive doses of drugs using programmable implants.