Method of layering a three-coated stent using pharmacological and polymeric agents

• US 6,251,136 B1
• Filed: 12/08/1999
• Issued: 06/26/2001
• Est. Priority Date: 12/08/1999
• Status: Expired due to Term

• Current Assignee: Advanced Cardiovascular Systems Incorporated (Abbott Laboratories)
• Original Assignee: Advanced Cardiovascular Systems Incorporated (Abbott Laboratories)
• Inventors: Wu, Steven Z-H, Guruwaiya, Judy A., Millare, Deborra Sanders
• Primary Examiner(s): O'Connor, Cary E.
• Application Number:
  US09/457,195
• Time in Patent Office: 566 Days
• Field of Search: 623/1.15, 623/1-4-, 623/1, 623/901, 623/12, 424/422-425, 604/265-266
• US Class Current: 623/1.46
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/072 Encapsulated stents, e.g. wire or whole stent embedded in lining
• CPC Class Codes: A61F 2002/91533 characterised by the phase between adjacent bands
• CPC Class Codes: A61F 2230/0013 Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped
• CPC Class Codes: A61L 2300/608 having two or more layers
• CPC Class Codes: A61L 2420/08 Coatings comprising two or more layers
• 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 27/16 Homopolymers or copolymers or vinylidene fluoride
• CPC Class Codes: C08L 31/04 Homopolymers or copolymers of vinyl acetate
• CPC Class Codes: C08L 89/00 Compositions of proteins; Compositions of derivatives thereof foodstuff preparations A23J3/00

Abstract

A pharmacological agent is applied to a stent in dry, micronized form over a sticky base coating. A membrane forming polymer, selected for its ability to allow the diffusion of the pharmacological agent therethrough, is applied over the entire stent. More specifically, a stent, typically a metal stent, has a layer of a sticky material applied to selected surfaces of the stent. A pharmacological agent is layered on the sticky material and a membrane forming a polymer coating is applied over the pharmacological agent. The membrane is formed from a polymer that permits diffusion of the pharmacological agent over a predetermined time period.

Claims

1. A method for coating a stent, comprising the steps of:

providing a stent;

applying a base layer of sticky material to selected surfaces of said stent;

applying pharmacological agent in micronized, dry form to selected surfaces coated by said base layer; and

applying a membrane forming polymer coating through which said pharmacological agent is able to diffuse to all surfaces of said stent.

2. The method of claim 1, wherein said base layer is applied to all surfaces of said stent.

3. The method of claim 1, wherein said stent is masked so as to limit application of said base layer to only selected surfaces of said stent.

4. The method of claim 1, wherein said pharmacological agent is applied to all surfaces having said base layer applied thereto.

5. The method of claim 1, wherein said stent is masked so as to limit application of said pharmacological agent to only selected surfaces coated with said base coat.

6. The method of claim 1, wherein a plurality of pharmacological agents are applied to selected surfaces having said base layer applied thereto.

7. The method of claim 6, wherein said plurality of pharmacological agents comprises a uniform mixture.

8. The method of claim 6, wherein selected pharmacological agents of said plurality of pharmacological agents are applied.

9. The method of claim 1, wherein, the base layer is selected from the group consisting of vitronectin, fibronectin, gelatin and collagen.

10. The method of claim 1, wherein said base layer is applied by dipping.

11. The method of claim 1, wherein said pharmacological agent is applied by rolling said stent in a mass of said pharmacological agent.

12. The method of claim 1, wherein said pharmacological agent is applied by blowing said dry, micronized particles onto said stent.

13. The method of claim 1, wherein said membrane forming polymer comprises ethylene vinyl acetate.

14. The method of claim 1, wherein said membrane forming polymer comprises a fluoropolymer film.

15. A coated stent, comprising:

an expandable structure;

a base coating of sticky material;

an intermediate coating of pharmacological agent in dry, micronized form; and

an outer coating of membrane forming polymer through which said pharmacological agent is capable of diffusing.

16. The coated stent of claim 15, wherein said base coating is present on only selected surfaces of said expandable structure.

17. The coated stent of claim 15, wherein said pharmacological agent is present on only selected base coated surfaces.

18. The coated stent of claim 15, wherein said intermediate coating comprises a plurality of pharmacological agents.

19. The coated stent of claim 15, wherein said plurality of pharmacological agents is homogeneously distributed throughout said intermediate coating.

20. The coated stent of claim 15, wherein said plurality of pharmacological agents is heterogeneously distributed throughout said intermediate coating.

21. The coated stent of claim 17, wherein said expandable structure has exterior surfaces and interior surfaces and wherein a first of said plurality of pharmacological agents is distributed on said exterior surfaces and a second of said pharmacological agents is distributed on said interior surfaces.

22. The coated stent of claim 15, wherein said outer coating comprises ethylene vinyl acetate.

23. The coated stent of claim 15, wherein said outer coating comprises a fluoropolymer film.