Bioabsorbable Polymeric Compositions and Medical Devices

• US 20100093946A1
• Filed: 10/13/2009
• Published: 04/15/2010
• Est. Priority Date: 10/11/2008
• Status: Abandoned Application

• Current Assignee: OrbusNeich Medical Pte Ltd
• Original Assignee: Orbusneich Medical Incorporated (Orbusneich Medical)
• Inventors: Cottone, Robert J., Thatcher, G. Lawrence
• Application Number:
  US12/578,432
• Publication Number:
  US 20100093946A1
• Time in Patent Office: Days
• US Class Current: 525/411
• CPC Class Codes: A61L 17/12 Homopolymers or copolymers of glycolic acid or lactic acid
• CPC Class Codes: A61L 24/0042 Materials resorbable by the body
• CPC Class Codes: A61L 24/043 Mixtures of macromolecular materials
• CPC Class Codes: A61L 26/0052 Mixtures of macromolecular compounds
• CPC Class Codes: A61L 26/009 Materials resorbable by the body
• CPC Class Codes: A61L 27/26 Mixtures of macromolecular compounds
• CPC Class Codes: A61L 27/58 Materials at least partially resorbable by the body
• CPC Class Codes: A61L 28/0026 Mixtures of macromolecular compounds
• CPC Class Codes: A61L 28/0057 Materials resorbable by the body
• CPC Class Codes: A61L 29/049 Mixtures of macromolecular compounds
• CPC Class Codes: A61L 29/148 Materials at least partially resorbable by the body
• CPC Class Codes: A61L 31/041 Mixtures of macromolecular compounds
• CPC Class Codes: A61L 31/148 Materials at least partially resorbable by the body
• CPC Class Codes: C08L 2205/02 containing two or more polymers of the same C08L -group
• CPC Class Codes: C08L 2666/18 Polyesters or polycarbonates according to C08L67/00 - C08L69/00; Derivatives thereof
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence

Abstract

The bioabsorbable polymers and compositions of the present invention may be formed into medical devices such as stents that can be crimped onto a catheter system for delivery into a blood vessel. The properties of the bioabsorbable polymers allow for both crimping and expansion of the stent. The crystal properties of the bioabsorbable polymers may change during crimping and/or expansion allowing for improved mechanical properties such as tensile strength and slower degradation kinetics. Typically, bioabsorbable polymers comprise aliphatic polyesters based on lactide backbone such as poly L-lactide, poly D-lactide, poly D,L-lactide, mesolactide, glycolides, lactones, as homopolymers or copolymers, as well as formed in copolymer moieties with co-monomers such as, trimethylene carbonate (TMC) or ε-caprolactone (ECL).

Claims

1. A composition comprising a blend formed from poly-L-lactide, poly-D-lactide or mixtures thereof and a copolymer moiety comprising poly-L-lactide or poly-D-lactide linked with ε

-caprolactone or trimethylcarbonate wherein, the poly-L-lactide or poly-D-lactide sequence in the copolymer moiety is random with respect to the distribution of ε

-caprolactone or trimethylcarbonate and where the wide-angle X-ray scattering (WAXS) exhibits 2θ

values of about 16.48 and about 18.76.

2. The composition of claim 1 wherein the co-polymer moiety comprises poly-L-lactide or poly-D-lactide linked with ε

-caprolactone.

3. The composition of claim 2 wherein the polymer moiety comprises poly-L-lactide.

4. The composition of claim 2 wherein the polymer moiety comprises poly-D-lactide.

5. The composition of claim 1 wherein the co-polymer moiety is poly-L-lactide or poly-D-lactide linked with TMC and the molecular weight of the co-polymer ranges from about 1.2 IV to about 2.6 IV.

6. The composition of claim 2 wherein the molecular weight of the co-polymer ranges from about 0.8 to about 6.0.

7. The composition of claim 1 wherein the WAXS 2θ

values further comprise peaks at about 11.92, about 20.66, about 22.24 and about 28.84.

8. The composition of claim 1 comprising a blend having about 20%-45% (w/w) poly-L-lactide, about 35% (w/w) to about 50% (w/w) poly-D-lactide and about 10% (w/w) to about 35% (w/w) poly L-lactide-co-TMC or poly-L-lactide-ε

-caprolactone.

9. The composition of claim 1 wherein the poly-L-lactide or poly-D-lactide ranges from about 20% (w/w) to about 95% (w/w).

10. The composition of claim 9 wherein the poly-L-lactide or poly-D-lactide ranges from about 50% (w/w) to about 95% (w/w).

11. The composition of claim 10 wherein the poly-L-lactide ranges from about 60% (w/w) to about 95% (w/w).

12. The composition of claim 11 wherein the poly-L-lactide ranges from about 70% (w/w) to about 80% (w/w).

13. The composition of claim 1 wherein greater than 7 L-lactides or D-lactides are arrayed sequentially in the copolymer moiety.

17. The composition of claim 1 wherein percent crystallinity ranges from about 0% (w/w) to about 10% (w/w).

18. The composition of claim 1 wherein the percent crystallinity ranges from about 20% (w/w) to about 70% (w/w).

19. The composition of claim 18 wherein the percent crystallinity ranges from about 30% (w/w) to about 60% (w/w).

20. The composition of claim 19 wherein the percent crystallinity ranges from about 30% (w/w) to about 60% (w/w).

23. The composition of claim 1 wherein the T_m peaks occur at about 180°

C. and about 217°

C.

14. A composition comprising a blend formed from poly-L-lactide, poly-D-lactide or mixtures thereof and a copolymer moiety comprising poly-L-lactide or poly-D-lactide linked with ε

-caprolactone or trimethylcarbonate wherein, the poly-L-lactide or poly-D-lactide sequence in the copolymer moiety is random with respect to the distribution of ε

-caprolactone or trimethylcarbonate, wherein there is at least about 95% (w/w) amorphous material in the composition.

15. The composition of claim 14 wherein there is at least about 98% (w/w) amorphous material.

16. The composition of claim 15 wherein there is at least about 99% (w/w) amorphous material.

21. A composition comprising a blend formed from poly-L-lactide, poly-D-lactide or mixtures thereof and a copolymer moiety comprising poly-L-lactide or poly-D-lactide linked with ε

-caprolactone or trimethylcarbonate wherein, the poly-L-lactide or poly-D-lactide sequence in the copolymer moiety is random with respect to the distribution of ε

-caprolactone or trimethylcarbonate and where the wide-angle X-ray scattering (WAXS) exhibits 2θ

values of about 16.65 and about 18.96.

22. The composition of claim 21 wherein the WAXS 2θ

values further comprise about 12.00, about 14.80, about 20.67, about 22.35, about 23.92, about 24.92, about 29.16 and about 31.28.

24. The composition of claim 21 wherein the T_m peaks occur at about 178°

C. and about 220°

C.

25. The composition of claim 21 wherein about T_g is 61°

C. and about 128°

C.