Demand-release bioactive composition for implantable medical devices

• US 20040180073A1
• Filed: 03/11/2003
• Published: 09/16/2004
• Est. Priority Date: 03/11/2003
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Hobot, Christopher M., Ebert, Michael J., Stokes, Kenneth B.
• Granted Patent: US 8,673,339 B2
• Time in Patent Office: Days
• US Class Current: 424/426
• CPC Class Codes: A61L 2300/222 Steroids, e.g. corticosteroids
• CPC Class Codes: A61L 2300/41 Anti-inflammatory agents, e.g. NSAIDs
• CPC Class Codes: A61L 2300/602 Type of release, e.g. controlled, sustained, slow
• CPC Class Codes: A61L 2300/606 Coatings
• CPC Class Codes: A61L 27/54 Biologically active materials, e.g. therapeutic substances A61L27/227 takes precedence
• CPC Class Codes: A61L 31/16 Biologically active materials, e.g. therapeutic substances A61L31/047 takes precedence
• CPC Class Codes: A61N 1/056 Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/0575 with drug delivery
• CPC Class Codes: A61P 29/00 Non-central analgesic, antipyretic or antiinflammatory agents, e.g. antirheumatic agents; Non-steroidal antiinflammatory drugs [NSAID]

Abstract

A biostable polymeric substrate of an implantable medical device unit includes a demand-release bioactive composition including one or more bioactive agents covalently bound to surface-modifying end groups of the substrate. Certain cellular activities, in proximity to the polymeric substrate, release substances reacting with the end groups such that the end groups release the one or more bioactive agents, which modify the certain cellular activities.

Claims

1. A medical device comprising:

an implantable unit;

a biostable polymeric substrate at least partially covering the unit and including surface-modifying end groups; and

a demand-release bioactive composition including one or more bioactive agents covalently bound to the surface-modifying end groups;

wherein certain cellular activities, in proximity to the polymeric substrate, release substances reacting with the end groups such that the end groups release the one or more bioactive agents, which modify the certain cellular activities.

2. The medical device of claim 1, wherein the implantable unit includes an intra-vascular portion.

3. The medical device of claim 1, wherein the surface modifying end groups are hydrolytically-stable and oxidizable.

4. The medical device of claim 3, wherein the surface modifying end groups are selected from the group comprising polyethylene oxide, polymethylene oxide, and poly(ethylene carbonate).

5. The medical device of claim 1, wherein the surface modifying end groups are oxidatively stable and acid or enzyme catalyzed hydrolyzable.

6. The medical device of claim 5, wherein the surface modifying end groups are selected from the group comprising acetal esters and acrylic esters.

7. The medical device of claim 1, wherein the certain cellular activities include macrophage activation.

8. The medical device of claim 1, wherein the one or more bioactive agents are selected from a group comprising anti-microbial agents, cytostatic agents, cytotoxic agents, anticoagulants, enzymes, and collagenase.

9. The medical device of claim 1, wherein the intra-vascular unit includes an elongated conductor and wherein the biostable polymeric substrate forms an outer insulative sheath about the conductor.

10. The medical device of claim 9, wherein

the implantable unit further includes an electrode coupled to the conductor and including an exposed surface;

and

the biostable polymeric substrate further forms an insulating element in proximity to the electrode.

11. The medical device of claim 1, further comprising an electrode including an exposed surface wherein the biostable polymeric substrate further forms an insulating element in proximity to the electrode.

12. The medical device of claim 11, further comprising a steroid coating formed on the exposed surface of the electrode.

13. The medical device of claim 1, wherein the demand-release bioactive composition forms a surface coating on the polymeric substrate.

14. The medical device of claim 1, wherein the demand-release bioactive composition is included within a bulk of the polymeric substrate.

15. A medical device, comprising:

an implantable unit including an elongated conductor;

a biostable polymeric substrate at least partially covering the elongated conductor, the substrate including surface-modifying end groups; and

a demand-release bioactive composition including one or more bioactive agents covalently bound to the surface-modifying end groups;

wherein certain cellular activities, in proximity to the polymeric substrate, release substances reacting with the end groups such that the end groups release the one or more bioactive agents, which modify the certain cellular activities;

the certain cellular activities including macrophage activation; and

the one or more bioactive agents including an anti-inflammatory agent.

16. The medical device of claim 15, further comprising

an electrode including an exposed surface and coupled to the conductor;

and

a steroid coating formed on the exposed surface of the electrode;

wherein the biostable polymeric substrate further forms an insulating element in proximity to the electrode.