Method of forming rate limiting barriers for implantable devices

• US 7,387,810 B2
• Filed: 02/07/2005
• Issued: 06/17/2008
• Est. Priority Date: 11/12/2002
• Status: Expired due to Fees

• Current Assignee: Advanced Cardiovascular Systems Incorporated
• Original Assignee: Advanced Cardiovascular Systems Incorporated
• Inventors: Hossainy, Syed F. A.
• Primary Examiner(s): CAMERON, ERMA C
• Application Number:
  US11/053,184
• Publication Number:
  US 20050191332A1
• Time in Patent Office: 1,226 Days
• Field of Search: 427/2.11, 427/2.12, 427/301, 427/387, 427/407, 427/512, 428/216, 428/336, 428/448, 428/451
• US Class Current: 427/2.1
• CPC Class Codes: A61L 27/34 Macromolecular materials
• CPC Class Codes: A61L 27/54 Biologically active materials, e.g. therapeutic substances A61L27/227 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: Y10T 428/31504 Composite [nonstructural laminate]
• CPC Class Codes: Y10T 428/31786 Of polyester [e.g., alkyd, etc.]
• CPC Class Codes: Y10T 428/31855 Of addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31935 Ester, halide or nitrile of addition polymer

Abstract

A method is disclosed for forming a coating on implantable medical devices including an interpenetrating polymer network that serves as a rate limiting barrier.

Claims

1. A method for fabricating a coating on an implantable medical device, the method comprising:

(a) forming a polymer layer on the device;

(b) applying on the polymer layer a precursor of an interpenetrating polymer network; and

(c) subjecting the device to a treatment to cause the precursor to form the interpenetrating polymer network on the device,

wherein the precursor is selected from the group consisting of poly(ethylene glycol)-acrylate, poly(ethylene glycol)-diacrylate, N-vinylpyrrolidone, derivatives of heparin, hyaluronic acid, derivatives of hyaluronic acid, poly(butyleneterephthalate-co ethylene glycol) (PBT-PEG), and mixtures thereof, and

wherein the derivative of heparin comprise heparin containing photoactivatable group(s), or heparin containing albumin-binding moiety(ies).

2. The method of claim 1, wherein the medical device is a stent.

3. The method of claim 1, wherein forming the polymer layer comprises including a therapeutic substance in the polymer layer.

4. The method of claim 3, wherein the therapeutic substance is selected from the group consisting of paclitaxel, docetaxel, rapamycin, 40-O-(2-hydroxy)ethyl-rapamycin, 40-O-(3-hydroxy)propyl-rapamycin, 40-O-[2-(2-hydroxy)ethoxy]ethyl-rapamycin, 40-O-tetrazole-rapamycin, and estradiol.

5. The method of claim 1, wherein the photoactivatable groups are derived from benzophenone or dithiocarbonate.

6. The method of claim 1, wherein the treatment includes exposing the device to UV-radiation.

7. The method of claim 6, further including adding a UV initiator to the precursor.

8. The method of claim 7, wherein the initiator comprises acetophenone or 2,2-dimethoxy-2-phenol-acetophenone.

9. The method of claim 1, wherein treatment includes exposing the device to light or to heat.

10. A method of fabricating a coating for a medical device comprising forming a coating including an interpenetrating polymer network and a drug on the medical device,

wherein the coating includes a first layer and a second layer over the first layer,

wherein the first layer comprises the drug and the second layer comprises the interpenetrating polymer network,

wherein the interpenetrating polymer network is formed by applying on the medical device a precursor of the interpenetrating polymer network and subjecting the device to a treatment to cause the precursor to form the interpenetrating polymer network on the device,

wherein the precursor is selected from the group consisting of poly(ethylene glycol)-acrylate, poly(ethylene glycol)-diacrylate, N-vinylpyrrolidone, derivatives of heparin, hyaluronic acid, derivatives of hyaluronic acid, poly(butyleneterephthalate-co ethylene glycol) (PBT-PEG), and mixtures thereof, and

wherein the derivative of heparin comprise heparin containing photoactivatable group(s), or heparin containing albumin-binding moiety(ies).

11. The method of claim 10, wherein the photoactivatable groups are derived from benzophenone or dithiocarbonate.

12. The method of claim 10, wherein treatment includes exposing the device to UV-radiation.

13. The method of claim 12, further including adding a UV initiator to the precursor.

14. The method of claim 13, wherein the initiator comprises acetophenone or 2,2-dimethoxy-2-phenol-acetophenone.

15. The method of claim 10, wherein treatment includes exposing the device to light or to heat.