Implantable or insertable medical devices for controlled delivery of a therapeutic agent

• US 20030235602A1
• Filed: 06/19/2002
• Published: 12/25/2003
• Est. Priority Date: 06/19/2002
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Inventors: Schwarz, Marlene C.
• Granted Patent: US 7,105,175 B2
• Time in Patent Office: Days
• US Class Current: 424/424
• CPC Class Codes: A61L 2300/416 Anti-neoplastic or anti-proliferative or anti-restenosis or anti-angiogenic agents, e.g. paclitaxel, sirolimus
• CPC Class Codes: A61L 2300/602 Type of release, e.g. controlled, sustained, slow
• CPC Class Codes: A61L 27/34 Macromolecular materials
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 29/085 Macromolecular materials
• CPC Class Codes: A61L 29/16 Biologically active materials, e.g. therapeutic substances A61L29/048 takes precedence
• CPC Class Codes: A61L 31/10 Macromolecular materials
• CPC Class Codes: A61P 9/00 Drugs for disorders of the cardiovascular system

Abstract

The present invention is directed to novel implantable or insertable medical devices that provide controlled release of a therapeutic agent. According to an embodiment of the present invention, a therapeutic-agent-releasing medical device is provided, which comprises: (a) an implantable or insertable medical device; (b) a release layer disposed over at least a portion of the implantable or insertable medical device; and (c) a therapeutic agent. The release layer comprises a styrene copolymer and at least one additional polymer. The release layer regulates the rate of release of the therapeutic agent from the medical device upon implantation or insertion of the device into a patient. The present invention is also directed to methods of forming the above implantable or insertable medical devices, methods of administering a therapeutic agent to a patient using such devices, and methods of modulating the release of therapeutic agent from such devices.

Claims

1. A therapeutic-agent-releasing medical device comprising:

(a) an implantable or insertable medical device;

(b) a release layer disposed over at least a portion of the implantable or insertable medical device, said release layer comprising (i) a styrene copolymer selected from an alternating styrene copolymer and a random styrene copolymer and (ii) an additional polymer; and

(c) a therapeutic agent, said release layer regulating the rate of release of the therapeutic agent from the medical device upon implantation or insertion of the device into a patient.

2. The therapeutic-agent-releasing medical device of claim 1, wherein said release layer is a carrier layer that comprises said therapeutic agent.

3. The therapeutic-agent-releasing medical device of claim 1, wherein said release layer is a barrier layer disposed over a therapeutic-agent-containing region that comprises said therapeutic agent.

4. The therapeutic-agent-releasing medical device of claim 1, wherein said implantable or insertable medical device is selected from a catheter, a guide wire, a balloon, a filter, a stent, a stent graft, a vascular graft, a vascular patch, a shunt, and an intraluminal paving system.

5. The therapeutic-agent-releasing medical device of claim 1, wherein said implantable or insertable medical device is adapted for implantation or insertion into the coronary vasculature, peripheral vascular system, esophagus, trachea, colon, biliary tract, urinary tract, prostate or brain.

6. The therapeutic-agent-releasing medical device of claim 1, wherein said therapeutic agent is selected from one or more of the group consisting of an anti-thrombotic agent, an anti-proliferative agent, an anti-inflammatory agent, an anti-migratory agent, an agent affecting extracellular matrix production and organization, an antineoplastic agent, an anti-mitotic agent, an anesthetic agent, an anti-coagulant, a vascular cell growth promoter, a vascular cell growth inhibitor, a cholesterol-lowering agent, a vasodilating agent, and an agent that interferes with endogenous vasoactive mechanisms.

7. The therapeutic-agent-releasing medical device of claim 1, wherein said styrene copolymer is an alternating copolymer.

8. The therapeutic-agent-releasing medical device of claim 1, wherein said styrene copolymer is a random copolymer.

9. The therapeutic-agent-releasing medical device of claim 1, wherein said styrene copolymer is a random copolymer of styrene and maleic anhydride.

10. The therapeutic-agent-releasing medical device of claim 1, wherein said styrene copolymer is a random copolymer of styrene and acrylonitrile.

11. The therapeutic-agent-releasing medical device of claim 1, wherein said styrene copolymer is a copolymer comprising (a) a monomer comprising a carbon-carbon double bond and (b) a styrene monomer.

12. The therapeutic-agent-releasing medical device of claim 11, wherein said monomer comprising a carbon-carbon double bond is an alkylene monomer.

13. The therapeutic-agent-releasing medical device of claim 12, wherein said alkylene monomer is selected from ethylene, propylene, butadiene, butylene, isobutylene and isoprene.

14. The therapeutic-agent-releasing medical device of claim 11, wherein said monomer comprising a carbon-carbon double bond is a vinyl monomer.

15. The therapeutic-agent-releasing medical device of claim 14, wherein said vinyl monomer is selected from one or more of vinyl ethers, vinyl acetates, vinyl aliphatics, halogenated vinyl compounds, vinyl pyrrolidone, acrylonitrile, vinyl alcohols, and vinyl acrylamides.

16. The therapeutic-agent-releasing medical device of claim 11, wherein said monomer comprising a carbon-carbon double bond is an acrylic acid monomer or acrylic acid derivative.

17. The therapeutic-agent-releasing medical device of claim 16, wherein said acrylic acid monomer or derivative is selected from methyl acrylate, methyl methacrylate, acrylic acid, methacrylic acid, hydroxyethyl acrylate, hydroxyethyl methacrylate, glyceryl acrylate, glyceryl methacrylate, acrylamide, methacrylamide and ethacrylamide.

19. The therapeutic-agent-releasing medical device of claim 1, wherein said additional polymer is an elastomer.

20. The therapeutic-agent-releasing medical device of claim 1, wherein said additional polymer is blended with said styrene copolymer in the release layer.

21. The therapeutic-agent-releasing medical device of claim 20, wherein the additional polymer is a copolymer comprising (a) one or more blocks of polyisobutylene and (b) one or more blocks of polystyrene or poly-alpha-methylstyrene.

22. The therapeutic-agent-releasing medical device of claim 20, wherein the additional polymer is a copolymer comprising (a) one or more blocks of polystyrene and (b) one or more polymer blocks of ethylene and butylene.

23. The therapeutic-agent-releasing medical device of claim 20, wherein the additional polymer is a poly(butyl methacrylate).

24. The therapeutic-agent-releasing medical device of claim 1, wherein said additional polymer is crosslinked with said styrene copolymer in the release layer.

25. The therapeutic-agent-releasing medical device of claim 1, wherein the rate of release of the therapeutic agent from the medical device upon implantation or insertion of the device into a patient corresponds to a sustained release profile.

26. A method of forming the therapeutic-agent-releasing medical device of claim 1, comprising:

(a) providing a solution comprising;

one or more solvents, said styrene copolymer and said additional polymer;

(b) applying said solution to a surface of said implantable or insertable medical device; and

(c) removing said solvents from said solution to form said release layer.

27. The method of claim 26, wherein said solution further comprises said therapeutic agent.

28. The method of claim 26, wherein said solution is applied over a therapeutic-agent-containing region that comprises said therapeutic agent.

29. The method of claim 26, wherein said solution is applied by a solvent spraying technique.

30. A method of releasing a therapeutic agent within a patient comprising (a) providing the therapeutic-agent-releasing medical device of claim 1 and (b) implanting or inserting the therapeutic-agent-releasing medical device of into a patient.

31. The method of claim 30, wherein said medical device is selected from a catheter, a guide wire, a balloon, a filter, a stent, a stent graft, a vascular graft, a vascular patch, a shunt, and an intraluminal paving system.

32. The method of claim 30, wherein said medical device is inserted into the vasculature.

33. The method of claim 32, wherein said therapeutic agent is released in the treatment of restenosis.

39. The therapeutic-agent-releasing medical device of claim 20, wherein the additional polymer is a copolymer comprising (a) one or more polyolefinic blocks and (b) one or polystyrenic blocks.

18. The therapeutic-agent-releasing medical device of claim 113, wherein said monomer comprising a carbon-carbon double bond is maleic anhydride or a maleic anhydride derivative.

34. A method of modulating a rate of release of a therapeutic agent by a release layer that (a) is disposed over at least a portion of an implantable or insertable medical device and (b) comprises (i) a styrene copolymer selected from an alternating styrene copolymer and a random styrene copolymer and (ii) an additional polymer, said method comprising changing the composition of said release layer.

35. The method of claim 34, wherein the rate of release is modulated by changing the amount of styrene copolymer relative to the amount of the additional polymer.

36. The method of claim 35, wherein the rate of release of the therapeutic agent is increased by increasing the amount of the styrene copolymer relative to the amount of the additional polymer, or the rate of release of the therapeutic agent is decreased by decreasing the amount of the styrene copolymer relative to the amount of the additional polymer.

37. The method of claim 34, wherein the rate of release is modulated by changing the molecular weight of the styrene copolymer.

38. The method of claim 34, wherein the rate of release is modulated by changing the amount of the styrene monomer relative to the total amount of monomer within the styrene copolymer.