Implantable medical devices having double walled microspheres
View Patent ↗An implantable medical device including at least one double-walled microsphere containing an active agent, and a biodegradable polymer layer containing the at least one double-walled microsphere.
1. An implantable nerve guide comprising a biodegradable polymer tube having a lumen comprising (a) an inner layer comprising a biodegradable polymer, into which are embedded double-walled microspheres containing glial cell-line derived neurotrophic factor, wherein poly(lactic-co-glycolic acid) layer forms a core and the poly(lactide) layer forms a shell of the double-walled microsphere and the microspheres provide sustained release of the bioactive neurotrophic factor over at least seven days in an amount effective in promoting nerve regeneration; and (b) an outer layer comprising a biodegradable polymer without microspheres, wherein said outer layer encapsulates the inner layer.
2. The implantable medical device of claim 1 , wherein the inner biodegradable polymer layer comprises poly(caprolactone).