COATINGS AND METHODS FOR CONTROLLED ELUTION OF HYDROPHILIC ACTIVE AGENTS

• US 20120100187A1
• Filed: 10/26/2011
• Published: 04/26/2012
• Est. Priority Date: 10/26/2010
• Status: Abandoned Application

• Current Assignee: Surmodics Incorporated
• Original Assignee: Surmodics Incorporated
• Inventors: Chappa, Ralph A., Burkstrand, Michael J., Babcock, David E.
• Application Number:
  US13/281,802
• Publication Number:
  US 20120100187A1
• Time in Patent Office: Days
• US Class Current: 424/400
• CPC Class Codes: A61L 2420/02 Methods for coating medical devices
• 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: C08L 31/04 Homopolymers or copolymers of vinyl acetate

Abstract

Embodiments of the invention include multi-layer coatings and methods for controlling the elution of hydrophilic active agents. In an embodiment, the invention includes a medical device including a substrate, a primer polymer layer disposed on the substrate, an expandable layer disposed on the primer polymer layer, and a hydrophilic active agent dispersed within the expandable layer. In an embodiment, the invention includes a method of forming a medical device including depositing a primer layer onto a substrate, the primer layer comprising a primer polymer. The method can further include depositing an expandable layer onto the primer layer, the expandable layer including an expandable polymer, and a hydrophilic active agent. The expandable layer can be deposited with a solvent that is effective to solvate both the expandable polymer and the primer polymer. Other embodiments are also included herein.

Claims

1. A medical device comprising:

a substrate;

a primer polymer layer disposed on the substrate;

an expandable layer disposed on the primer polymer layer; and

a hydrophilic active agent dispersed within the expandable layer.

2. The medical device of claim 1, further comprising a top coat disposed on the expandable layer, the top coat comprising polyethylene-co-vinyl acetate (PEVA).

3. The medical device of claim 2, the polyethylene-co-vinyl acetate having a vinyl acetate concentration of between about 12 percent and 33 percent by weight.

4. The medical device of claim 1, the expandable layer configured to expand in volume at least about 5% after insertion into a subject.

5. The medical device of claim 2, the expandable layer comprising polyethylene-co-vinyl acetate (PEVA).

6. The medical device of claim 5, the polyethylene-co-vinyl acetate in the expandable layer having a vinyl acetate concentration of greater than or equal to about 33 percent by weight and less than or equal to about 40 percent by weight.

7. The medical device of claim 1, the expandable layer comprising at least one selected from the group consisting of cross-linked polysiloxane (silicone rubber) and butyl rubber.

8. The medical device of claim 1, the expandable layer comprising a hydrogel.

9. The medical device of claim 1, the expandable layer comprising poly lactide-co-glycolide (PLGA).

10. The medical device of claim 1, the expandable layer having a thickness of at least about 5 microns.

11. The medical device of claim 1, the primer layer configured to expand in volume less than about 5% after insertion into a subject.

12. The medical device of claim 1, the primer polymer layer comprising poly-n-butyl methacrylate (PBMA).

13. The medical device of claim 1, the primer polymer layer comprising polystyrene.

14. The medical device of claim 1, the primer polymer layer having a thickness of at least about 1 micron.

15. The medical device of claim 1, the hydrophilic active agent comprising at least one selected from the group consisting of a protein and a nucleic acid.

16. The medical device of claim 1, the expandable layer comprising at least trace amounts of a solvent effective to solvate the primer polymer layer disposed on the substrate.

17. The medical device of claim 1, the substrate comprising a portion of at least one selected from the group consisting of an eye coil, a stent, an electrical stimulation lead, and a bone screw.

18. The medical device of claim 1, the substrate selected from the group consisting of glasses, metals, and ceramics.

19. A method of forming a medical device comprising:

depositing a primer layer onto a substrate, the primer layer comprising a primer polymer; and

depositing an expandable layer onto the primer layer, the expandable layer comprising

a expandable polymer, and

a hydrophilic active agent;

wherein the expandable layer is deposited with a solvent that is effective to solvate both the expandable polymer and the primer polymer.

20. The method of claim 19, further comprising depositing a top coat onto the expandable layer.