Cerebral aneurysms can be life threatening and because the blood vessel is weak they are subject to rupture. Platinum coils are currently used as an experimental treatment for inoperable cerebral aneurysms and function by inducing thrombosis within the aneurysm. The metal/thrombus fills the aneurysm, thereby restoring a more normal blood flow in the blood vessel. Currently used coils do not stimulate tissue in-growth into the aneurysm or blood vessel wall, thereby leaving the vessel wall weakened and with a continued susceptibility to rupture. We propose improving aneurysm coils by coating a modified, proprietary heparin onto the surface, and then using the affinity of hepann to further complex basic fibroblast growth factor (FGF-2). The coating is simple and cost-effective as it is performed using adsorption and affinity techniques. The FGF will encourage local cell migration and proliferation resulting in a strengthening of the aneurysm wall and a filling of the aneurysm with cellular material. Our initial studies suggest that the heparin can be modified to alter the rate of release from a substrate, a factor that could help control the bioavailability in vivo. The Phase I studies will develop the coated coils and perform initial animal evaluations.