Medical implant

• US 8,540,765 B2
• Filed: 02/09/2012
• Issued: 09/24/2013
• Est. Priority Date: 05/20/2009
• Status: Active Grant

• Current Assignee: Lyra Therapeutics, Inc.
• Original Assignee: 480 Biomedical, Inc.
• Inventors: Palasis, Maria, Cheng You, Chang, Concagh, Daniel, Core, Lee, Ho, Kicherl, Sharma, Upma, Zugates, Greg
• Primary Examiner(s): Stewart, Alvin J.
• Application Number:
  US13/370,025
• Publication Number:
  US 20120143300A1
• Time in Patent Office: 593 Days
• Field of Search: 623 111- 123, 623 138- 154, 606191-195
• US Class Current: 623/1.38
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2210/0014 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0036 differing in thickness
• CPC Class Codes: A61F 2250/0048 differing in mechanical expandability, e.g. in mechanical, self- or balloon expandability
• CPC Class Codes: A61L 2300/606 Coatings
• CPC Class Codes: A61L 2420/02 Methods for coating medical devices
• 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 31/10 Macromolecular materials
• CPC Class Codes: A61L 31/16 Biologically active materials, e.g. therapeutic substances A61L31/047 takes precedence
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence

Abstract

Disclosed is a self-expanding medical implant for placement within a lumen of a patient. The implant comprises a woven or non-woven structure having a substantially tubular configuration, and is designed to be low-profile such that it is deliverable with a small diameter catheter. The implant has a high recoverability and desired mechanical properties.

Claims

1. An implantable medical device, comprising:

a self-expanding tubular structure comprising at least one strand comprising a first polymer characterized by a modulus of elasticity greater than about 1 GPa; and

a second polymer at least partially and conformally coating said strand, said second polymer being an elastomeric thermoset polymer characterized by a percent elongation to break that is greater than about 150 percent at 37°

C.;

wherein the second polymer increases the mass of said self-expanding tubular structure by at least about 20 percent.

2. The implantable medical device of claim 1, wherein said first polymer is biodegradable.

3. The implantable medical device of claim 2, wherein said first polymer comprises poly(lactic acid co-glycolic acid).

4. The implantable medical device of claim 3, wherein said poly(lactic acid co-glycolic acid) comprises at least about 75 weight percent of lactic acid.

5. The implantable medical device of claim 4, wherein said poly(lactic acid co-glycolic acid) comprises about 85 weight percent of lactic acid.

6. The implantable medical device of claim 4, wherein said second polymer is poly(lactic acid-co-caprolactone) comprising about 50 to 70 weight percent lactic acid, wherein said polymer is cross-linked.

7. The implantable medical device of claim 6, wherein said poly(lactic acid-cocaprolactone) is crosslinked with hexamethylene diisocyanate.

8. The implantable medical device of claim 6, wherein the number average molecular weight (Mn) of said second polymer is greater than about 24,000 Da and less than about 100,000 Da.

9. The implantable medical device of claim 3, wherein said poly(lactic acid co-glycolic acid) comprises up to about 20 weight percent of lactic acid.

10. The implantable medical device of claim 1, wherein said first polymer is characterized by a modulus of elasticity greater than about 6 GPa.

11. The implantable medical device of claim 1, wherein said second polymer is biodegradable.

12. The implantable medical device of claim 11, wherein said second polymer is a random copolymer that is crosslinked.

13. The implantable medical device of claim 11, wherein said second polymer is selected from the group consisting of poly(lactic acid-co-caprolactone), poly(glycolide-co-caprolactone, poly trimethylene carbonate, and poly(lactic acid-co-dioxanone) and wherein said second polymer is cross-linked.

14. The implantable medical device of claim 1, wherein said second polymer is characterized by an elastic segment having a glass transition temperature less than about 5, degree. C.

15. The implantable medical device of claim 1 wherein said self-expanding tubular structure is a braided structure.

16. The implantable medical device of claim 15, wherein said braided structure comprises between 16 and 48 strands.

17. The implantable medical device of claim 16, wherein said strands form an average braid angle of between about 90 degrees and about 135 degrees.

18. The implantable medical device of claim 17, wherein said strands form an average braid angle of between about 110 degrees and about 135 degrees.

19. The implantable medical device of claim 1, further comprising a therapeutic agent within at least one of said first polymer material and said second polymer material.

20. The implantable medical device of claim 1, wherein the second polymer increases the mass of said self-expanding tubular structure by at least about 30 percent.

21. The implantable medical device of claim 1, further comprising a third polymer at least partially coating said second polymer.

22. The implantable medical device of claim 21, further comprising a therapeutic agent within said third polymer.

23. The implantable medical device of claim 1, wherein said second polymer comprises a first segment having a Tg less than about 5.degree. C. and a second segment that is harder than the first segment.

24. The implantable medical device of claim 1, wherein said self expanding tubular structure has a first end and a second end.

25. An implantable medical device, comprising:

a self-expanding tubular structure comprising;

at least one biodegradable strand comprising poly(lactic acid-co-glycolic acid) comprising at least 75 weight percent of lactic acid; and

poly(lactic acid-co-caprolactine) at least partially coating said strand;

wherein said poly9lactic acid-co-caprolactone) is cross-linked and has a number average molecular weight (Mn) greater than 30,000 Da;

wherein said poly(lactic acid co-caprolactone) increases the mass of said self-expanding tubular structure by at least 24 percent;

wherein said self-expanding tubular structure is a braided structure comprising between 16 and 48 strands forming an average braid angle of between 110 degrees and 135 degrees.