Subcutaneous infusion cannula

• US 6,475,196 B1
• Filed: 08/18/2000
• Issued: 11/05/2002
• Est. Priority Date: 08/18/2000
• Status: Active Grant

• Current Assignee: Minimed, Inc. (Medtronic Plc)
• Original Assignee: Minimed, Inc. (Medtronic Plc)
• Inventors: Vachon, David J.
• Primary Examiner(s): Walberg, Teresa
• Assistant Examiner(s): FASTOVSKY, LEONID M
• Application Number:
  US09/643,662
• Time in Patent Office: 809 Days
• Field of Search: 604/59, 604/132, 604/158, 604/285, 514/772.3
• US Class Current: 604/265
• CPC Class Codes: A61L 2300/43 Hormones, e.g. dexamethasone
• 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 29/085 Macromolecular materials
• CPC Class Codes: A61L 29/16 Biologically active materials, e.g. therapeutic substances A61L29/048 takes precedence

Abstract

Provided is an infusion cannula modified to incorporate one of more medicinal agents. The infusion cannula has a tube having an inner lumen and an external surface, and is made of a flexible, biologically compatible elastomeric material, with a coating adhered to the external surface of the tube. The coating contains a medicinal agent in a polymer matrix. Preferably, the polymer is capable of sustained release of the medicinal agent. The infusion cannula can be produced by coating a tube with a medicinal agent in a polymer matrix. In some embodiments, the coating involves dipping the tube into the polymer matrix, or spraying or painting the polymer matrix onto the tube. Additionally provided is a method for infusing a substance into a subject by inserting the cannula into subcutaneous tissue of the subject and delivering the substance into the cannula, thereby infusing the substance into the subject through the cannula.

Claims

1. An infusion cannula comprising:

(a) a tube having an inner lumen and an external surface, wherein the tube comprises an elastomeric material; and

(b) a coating adhered to the external surface of the tube, wherein the coating comprises a medicinal agent and a polymer matrix,

wherein the polymer matrix comprises polyurea, and wherein the coating is prepared from a solution comprising 6.5 to 8.5% polymer, about 0.91 to 0.93% medicinal agent, and a solvent.

2. The infusion cannula of claim 1, wherein the medicinal agent is embedded in the polymer matrix and the polymer matrix is capable of sustained release of the medicinal agent.

3. The infusion cannula of claim 1, wherein the elastomeric material comprises polyurethane, polyether(amide), polyester, PEBA, thermoplastic elastomeric olefin, copolyester, styrenic thermoplastic elastomer, or polyamide.

4. The infusion cannula of claim 1, wherein the elastomeric material comprises polyurethane or polyurea.

5. The infusion cannula of claim 1, wherein the polymer matrix further comprises a diisocyanate.

6. The infusion cannula of claim 5, wherein the polymer matrix further comprises a siloxane polymer.

7. The infusion cannula of claim 5, wherein the polymer matrix further comprises a chain extender.

8. The infusion cannula of claim 1, wherein the coating is prepared from a solution comprising about 7.5% polymer and about 0.91% dexamethasone.

9. The infusion cannula of claim 1, wherein the solvent comprises tetrahydrofuran.

10. The infusion cannula of claim 1, wherein the tube has a gauge of about 24.

11. The infusion cannula of claim 1, wherein the tube has a length of about 0.35 inches.

12. The infusion cannula of claim 1, wherein the medicinal agent comprises an anti-inflammatory, anti-bacterial, anti-viral, anti-proliferative, or disinfecting agent.

13. The infusion cannula of claim 1, wherein the medicinal agent is selected from the group consisting of dexamethasone, cefazolin, benzalkonium chloride, silver or a salt thereof, silver-platinum, copper, and acyclovir.

14. The infusion cannula of claim 1, wherein the coating, exclusive of solvent, comprises about 89.16% polymer and about 10.84% dexamethasone.

19. A method for infusing a substance into a subject comprising inserting the cannula of claim 1 into subcutaneous tissue of the subject and delivering the substance into the cannula.

20. The infusion cannula of claim 1 wherein the coating is prepared from a solution that does not include ethanol.

15. A method for producing an infusion cannula comprising coating an elastomeric tube with a polymer matrix, wherein the polymer matrix comprises a medicinal agent.

16. The method of claim 15, wherein the coating comprises dipping the elastomeric tube into the polymer matrix.

17. The method of claim 15, wherein the coating comprises spraying or painting the polymer matrix onto the tube.

18. An infusion cannula produced by the method of claim 15.