Lyophilized foams of end block containing absorbable polymers

• US 9,896,560 B2
• Filed: 06/02/2015
• Issued: 02/20/2018
• Est. Priority Date: 06/02/2015
• Status: Active Grant

• Current Assignee: Ethicon Incorporated (Johnson & Johnson)
• Original Assignee: Ethicon Incorporated (Johnson & Johnson)
• Inventors: Donners, Jackie, Wisnudel, Marc, Timmer, Mark
• Primary Examiner(s): Vo, Hai
• Application Number:
  US14/728,226
• Publication Number:
  US 20160355661A1
• Time in Patent Office: 994 Days
• CPC Class Codes: A61L 27/18 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 27/58 Materials at least partially resorbable by the body
• CPC Class Codes: A61L 31/06 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds A61L31/041 takes precedence
• CPC Class Codes: A61L 31/146 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 31/148 Materials at least partially resorbable by the body
• CPC Class Codes: C08G 63/08 Lactones or lactides
• CPC Class Codes: C08J 2201/048 Elimination of a frozen liquid phase
• CPC Class Codes: C08J 2201/0482 the liquid phase being organic
• CPC Class Codes: C08J 2205/02 the finished foam itself being a gel or a gel being temporarily formed when processing the foamable composition
• CPC Class Codes: C08J 2205/05 Open cells, i.e. more than 50% of the pores are open
• CPC Class Codes: C08J 2207/10 Medical applications, e.g. biocompatible scaffolds
• CPC Class Codes: C08J 2300/16 Biodegradable polymers
• CPC Class Codes: C08J 2367/04 Polyesters derived from hydroxy carboxylic acids, e.g. lactones C08J2367/06 takes precedence
• CPC Class Codes: C08J 9/26 by elimination of a solid phase from a macromolecular composition or article, e.g. leaching out
• CPC Class Codes: C08J 9/36 After-treatment C08J9/22 takes precedence
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence

Abstract

Novel absorbable foams, lyophilizing solutions, and lyophilizing and annealing processes are disclosed. The foams are made from copolymers of glycolide and epsilon-caprolactone. The foams are useful in or as implantable medical devices.

Claims

1. An absorbable polymer foam, comprising:

a semicrystalline absorbable segmented block copolymer having a random center block segment of repeating units of polymerized glycolide and polymerized epsilon-caprolactone and an end block segment that comprises predominantly polymerized glycolide, wherein the mole ratio of polymerized glycolide to polymerized epsilon-caprolactone of the entire segmented copolymer is between about 55;

45 to about 65;

35, and having a mole ratio of polymerized glycolide to polymerized epsilon-caprolactone in the random center block segment between about 45;

55 to about 52;

48,

wherein the absorbable polymer foam has a compressive pressure at 2 mm height greater than 1.05 gf/mm² after 28 days of incubation in a buffer of pH 7.27 at 37°

C. under continuous compression.

2. The foam of claim 1 wherein the copolymer has an inherent viscosity between about 0.5 dL/g and about 2.5 dl/g, as measured in a 0.1 g/dl solution of HFIP at 25°

C.

3. The foam of claim 1 having a solid content from about 3 weight percent to about 20 weight percent.

4. The foam of claim 3 having the solid content between about 5 weight percent and 15 weight percent.

5. The foam of claim 1 having a thickness between about 0.5 mm to about 13 mm.

6. The foam of claim 5 having the thickness between about 1 mm and about 5 mm.

7. The foam of claim 1 prepared from 10 weight percent lyophilization solution.

8. The foam of claim 1 having a degradation coefficient less than −

0.095 gf/(mm² day) when incubated in a buffer of pH 7.27 at 37°

C. under continuous compression.

9. The foam of claim 8 prepared from 10 weight percent lyophilization solution.

10. The foam of claim 1 having mechanical integrity at least 30 days post-implantation.

11. The foam of claim 1 having mechanical integrity at least 60 days post-implantation.

12. The foam of claim 1 having a crystallinity level greater than about 10 percent.

13. The foam of claim 1 having a crystallinity level greater than about 20 percent.