Claims for Patent: 4,947,840

Summary for Patent: 4,947,840

Title:	Biodegradable templates for the regeneration of tissues
Abstract:	This invention relates to porous, biodegradable materials in which the pore size, biodegradation rate, and pore volume fraction are controlled and within values at which skin contraction rates around an implant-containing wound are delayed or slowed.
Inventor(s):	Yannas; Ioannis V. (Newton, MA), Lee; Elaine (Medford, MA), Ferdman; Ariel (Cambridge, MA)
Assignee:	Massachusetts Institute of Technology (Cambridge, MA)
Application Number:	07/087,772
Patent Claims:	1. A method of delaying or arresting contraction of skin bordering a wound site and promoting tissue regeneration, comprising applying a biodegradable material with a pore size of between about 9 .mu.m and 630 .mu.m, a pore volume fraction of greater than about 80%, and a biodegradation rate sufficient to significantly delay or arrest the rate of wound contraction such that the time it takes a wound to contract to one-half of its original area is greater than approximately 15 days. 2. A method as in claim 1 wherein the biodegradable material comprises collagen molecules. 3. A method as in claim 1 wherein the biodegradable material comprises collagen molecules that are crosslinked and covalently bonded with a second material selected from the group consisting of glycosaminoglycans, glycoproteins, structural proteins and growth factors. 4. A method as in claim 3 wherein the second material is a glycosaminoglycan selected from the group consisting of chondroitin 6-sulfate, chondroitin 4-sulfate, heparin, heparan sulfate, keratan sulfate, dermatan sulfate, chitin and chitosan. 5. A method as in claim 3 wherein the second material is a glycoprotein selected from the group consisting of fibronectin, laminin and chondronectin. 6. A method as in claim 3 wherein the second material is a structural protein comprising elastin. 7. A method as in claim 3 wherein the second material is a growth factor selected from the group consisting of epidermal growth factor, platelet derived growth factor, tissue angiogenesis growth factor and bone growth factor. 8. A method as in claim 3 wherein the biodegradable material is crosslinked by contacting it with an aqueous aldehyde. 9. A method as in claim 8 wherein the aldehyde is glutaraldehyde. 10. A method as in claim 1 wherein the biodegradable material contains pores with an average size ranging from about 20 .mu.m to about 125 .mu.m. 11. A method as in claim 1 wherein the biodegradable material has a degradation rate in an in vitro collagenase assay of below about 140 enzyme units. 12. A method as in claim 11 wherein the biodegradable material has a degradation rate in an in vitro collagenase-assay of below about 120 enzyme units.

Details for Patent 4,947,840

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Smith & Nephew, Inc.	SANTYL	collagenase	Ointment	101995	06/04/1965		2039-03-29