Polyactic-polyglycolic acid copolymer combined with decalcified freeze-dried bone for use as a bone repair material

• US 4,637,931 A
• Filed: 10/09/1984
• Issued: 01/20/1987
• Est. Priority Date: 10/09/1984
• Status: Expired due to Fees

• Current Assignee: United States Of America As Represented By The Secretary Of The Army (Government of the United States of America)
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Schmitz, John P.
• Primary Examiner(s): Rosen, Sam
• Application Number:
  US06/658,945
• Time in Patent Office: 833 Days
• Field of Search: 424/95, 424/78
• US Class Current: 424/426
• CPC Class Codes: A61L 27/18 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/3608 Bone, e.g. demineralised bone matrix [DBM], bone powder
• CPC Class Codes: A61L 27/365 Bones
• CPC Class Codes: A61L 27/3683 subjected to a specific treatment prior to implantation, e.g. decellularising, demineralising, grinding, cellular disruption/non-collagenous protein removal, anti-calcification, crosslinking, supercritical fluid extraction, enzyme treatment
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence

Abstract

A novel bone repair material consisting essential of decalcified freeze-dd bone and biodegradable, biocompatible copolymer has been developed for improving and accelerating the healing of osseous tissue. The bone repair material was prepared by combining decalcified bone with a copolymer consisting essentially of a 50:50 poly(L)(-)lactide co-glycolide.

Claims

1. A method for promoting the healing of osseous tissue which comprises implanting at the site of the broken osseous tissue a therapeutically-effective amount of a composition comprising decalcified freeze-dried bone incorporated into a biodegradable polymeric matrix comprised of a copolymer of poly(L)(-)lactide co-glycolide.

2. The method of claim 1 wherein said bone is cortical bone which was decalcified in 0.6 normal hydrochloric acid.

3. The method of claim 1 wherein the amount of the decalcified freeze-dried bone is about 40 to 60 percent by weight of said polymeric matrix.

4. The method of claim 3 wherein the amount of the decalcified freeze-dried bone is about 45 to 55 percent by weight of said polymeric matrix.

5. The method of claim 4 wherein the amount of decalcified freeze-dried bone is about 50 percent of said polymeric matrix.

6. The method of claim 1 wherein the copolymer is 50:

50 poly(L)(-)lactide co-glycolide.

7. The method of claim 6 wherein the amount of decalcified freeze-dried bone is about 50 percent of said copolymer.

8. The method of claim 7 wherein the decalcified freeze-dried bone has a particle size in the range of 149 to 590 μ

m.

9. The method of claim 8 wherein the decalcified freeze-dried bone has a particle size in the range of 200 to 400μ

m.

10. The method of claim 2 wherein the amount of decalcified freeze-dried bone, having a particle size in the range of 200 to 400 μ

m, is about 50 percent by weight and the copolymer is 50;

50 poly(L)(-)lactide co-glycolide.

11. A pharmaceutical composition useful in promoting the healing of broken osseous tissue comprising decalcified freeze-dried bone incorporated into a biodegradable polymeric matrix comprised of a copolymer of poly(L)(-)lactide co-glycolide.

12. The composition of claim 11 wherein said bone is cortical bone which was decalcified in 0.6 normal hydrochloric acid.

13. The composition of claim 12 wherein the amount of decalcified freeze-dried bone is about 40 to 60 percent by weight of said polymeric matrix.

14. The composition of claim 13 wherein the amount of decalcified freeze-dried bone is about 45 to 55 percent by weight of said polymeric matrix.

15. The composition of claim 14 wherein the amount of decalcified freeze-dried bone is about 50 percent by weight of said polymeric matrix.

16. The composition of claim 15 wherein the copolymer is 50:

50 poly(L)(-)lactide co-glycolide.

17. The composition of claim 16 wherein the decalcified freeze-dried bone has a particle size in the range of 149 to 590 μ

m.

18. The composition of claim 16 wherein the decalcified freeze-dried bone has a particle size in the range of 200 to 400 μ

m.

19. The composition of claim 18 wherein said bone is cortical bone which was decalcified in 0.6 normal hydrochloric acid, and incorporated into said copolymer in the amount of 50 percent by weight.