CONTROLLED RELEASE SYSTEMS FROM POLYMER BLENDS

• US 20100189763A1
• Filed: 01/22/2010
• Published: 07/29/2010
• Est. Priority Date: 01/23/2009
• Status: Abandoned Application

• Current Assignee: SurModics Pharmaceuticals, Inc (Rag-Stiftung)
• Original Assignee: SurModics Pharmaceuticals, Inc (Rag-Stiftung)
• Inventors: Nettles, Heather
• Application Number:
  US12/692,027
• Publication Number:
  US 20100189763A1
• Time in Patent Office: Days
• US Class Current: 424/426
• CPC Class Codes: A61K 31/485 Morphinan derivatives, e.g. morphine, codeine
• CPC Class Codes: A61K 9/1647 Polyesters, e.g. poly(lactide-co-glycolide)

Abstract

Described herein are improved microparticles. In one aspect, the microparticles comprise a first polymer and a second polymer wherein the second polymer is different than the first polymer. In further aspects, the microparticles comprise a bioactive agent encapsulated therein.

Claims

1. A controlled release system comprising a polymer matrix comprising a first polymer and a second polymer that is different from the first polymer;

and a bioactive agent encapsulated in the polymer matrix.

2. The controlled release system of claim 1, wherein the first polymer and the second polymer have different degradation rates in an aqueous medium.

3. The controlled release system of claim 1, wherein the first polymer and the second polymer have one or more different non-repeating units.

4. The controlled release system of claim 1, wherein the first polymer and the second polymer have one or more different end groups.

5. The controlled release system of claim 1, wherein the first polymer has a more polar end group than one or more end group(s) of the second polymer.

6. The controlled release system of claim 1, wherein the first polymer has a more polar end group than all end group(s) of the second polymer.

7. The controlled release system of claim 1, wherein the first polymer has one or more carboxylic acid end groups, and wherein the second polymer has one or more ester end groups.

8. The controlled release system of claim 1, wherein the first polymer and the second polymer have different molecular weights.

9. The controlled release system of claim 1, wherein the first polymer has a molecular weight that is at least about 3000 Daltons greater than the molecular weight of the second polymer.

10. The controlled release system of claim 1, wherein the first polymer exhibits a glass-transition temperature that is less than the glass-transition temperature exhibited by the second polymer.

11. The controlled release system of claim 1, wherein the first polymer exhibits a glass-transition temperature that is from about 5°

C. to about 50°

C. less than the glass-transition temperature exhibited by the second polymer.

12. The controlled release system of claim 1, wherein the controlled release system further comprises a third polymer that is different from the first and second polymers.

13. The controlled release system of claim 1, wherein the first and second polymers are both poly(lactide-co-glycolide) polymers.

14. The controlled release system of claim 1, wherein the first and second polymers are both poly(lactide-co-glycolide) polymers;

wherein the ratio of lactide to glycolide is from about 90;

10 to about 40;

60.

15. The controlled release system of claim 1, wherein the first and second polymers are both poly(lactide-co-glycolide) polymers;

wherein the ratio of lactide to glycolide is from about 85;

15 to about 50;

50.

16. The controlled release system of claim 1, wherein the controlled release system is an implant device or a microparticle.

17. The controlled release system of claim 1, wherein the controlled release system is a bioactive agent-loaded rod.

18. The controlled release system of claim 1, wherein the first polymer is poly(lactide), and the second polymer is poly(lactide-co-glycolide) having a ratio of lactide to glycolide of about 75:

25;

wherein the ratio of the first polymer to the second polymer is about 75;

25.

19. The controlled release system of claim 1, wherein the first polymer is poly(lactide), and the second polymer is poly(lactide-co-glycolide) having a ratio of lactide to glycolide of about 50:

50;

wherein the ratio of the first polymer to the second polymer is about 75;

25.

20. The controlled release system of claim 1, wherein the first polymer is poly(lactide), and the second polymer is polyethylene glycol (PEG) having a molecular weight of about 1500 Daltons;

wherein the ratio of the first polymer to the second polymer is about 75;

25.