Drug-eluting stent and methods of making the same

• US 20060287709A1
• Filed: 08/25/2006
• Published: 12/21/2006
• Est. Priority Date: 11/13/2002
• Status: Active Grant

• Current Assignee: Advanced Cardiovascular Systems Incorporated (Abbott Laboratories)
• Original Assignee: Advanced Cardiovascular Systems Incorporated (Abbott Laboratories)
• Inventors: Rao, K.T. Venkateswara
• Granted Patent: US 8,128,687 B2
• Time in Patent Office: Days
• US Class Current: 623/1.150
• 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 2002/91508 the meander having a difference in amplitude along the band
• CPC Class Codes: A61F 2002/91533 characterised by the phase between adjacent bands
• CPC Class Codes: A61F 2002/91575 connected peak to trough
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0068 the pharmaceutical product being in a reservoir
• CPC Class Codes: A61F 2250/0071 breakable or frangible
• 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

Abstract

An intravascular stent having a prefabricated, patterned polymeric sleeve for controlled release of therapeutic drugs and for delivery of the therapeutic drugs in localized drug therapy in a blood vessel is disclosed. The polymeric sleeve is attached to at least a portion of an outside surface area of the stent structure. Alternatively, a plurality of individual microfilament strands are longitudinally attached to an outer surface of a stent structure in a spaced apart orientation and loaded with at least one therapeutic drug for the release thereof at a treatment site. The stent has a high degree of flexibility in the longitudinal direction, yet has adequate vessel wall coverage and radial strength sufficient to hold open an artery or other body lumen. Methods for making the same are also disclosed.

Claims

1. A drug-delivery stent delivery system for controlled release of therapeutic drugs and for delivery of the therapeutic drugs in localized drug therapy in a blood vessel, comprising:

a pattern of struts interconnected to form a structure that contacts the walls of a body lumen to maintain the patency of the vessel, wherein a polymeric sleeve, fabricated as a prepatterned tube is loaded with at least one therapeutic drug for the release thereof at a treatment site, the polymeric sleeve being attached to at least a portion of an outside surface area of the stent structure, wherein the polymeric sleeve is fabricated from a predesigned pattern having individual drug-loaded elements to form a desired local drug-elution profile.

2. The drug-delivery stent delivery system of claim 1, wherein the predesigned pattern of the polymeric sleeve as a solid tube is formed by at least one of the techniques of etching and cutting.

3. A drug-delivery stent delivery system for controlled release of therapeutic drugs and for delivery of the therapeutic drugs in localized drug therapy in a blood vessel, comprising:

a pattern of struts interconnected to form a structure that contacts the walls of the body lumen to maintain the patency of the vessel;

a plurality of individual filament strands attached to an outside surface of the stent structure in a spaced apart orientation, wherein the plurality of filament strands are each loaded with at least one therapeutic drug for the release thereof at a treatment site;

the plurality of individual filament strands each being positioned longitudinally across the outside surface of the stent structure.

4. The drug-delivery stent delivery system of claim 3, wherein the pattern of struts comprises a plurality of flexible cylindrical rings being expandable in a radial direction, each of the rings having a first delivery diameter and a second implanted diameter and being aligned on a common longitudinal axis.

5. The drug-delivery stent delivery system of claim 3, wherein at least one link of the stent is attached between adjacent rings to form the stent.

6. The drug-delivery stent delivery system of claim 3, wherein the stent is formed at least in part of a metallic material.

7. The drug-delivery stent delivery system of claim 6, wherein the metallic material forming the stent is from the group consisting of stainless steel, platinum, titanium, tantalum, nickel-titanium, cobalt-chromium, and alloys thereof.

8. The drug-delivery stent delivery system of claim 3, wherein the therapeutic drug is selected from the group consisting of antiplatelets, anticoagulants, antifibrins, antiinflammatories, antithrombins, and antiproliferatives.

9. The drug-delivery stent delivery system of claim 3, wherein the drug-loaded filament strands each have a thickness in the range of about 0.001 to about 100 microns and a width in the range of about 0.001 to about 50 microns.

10. The drug-delivery stent delivery system of claim 3, wherein each of the drug-loaded filament strands have a rectangular cross section with a first side, a second side, a third side, and a fourth side.

11. The drug-delivery stent delivery system of claim 10, wherein a barrier coating layer is disposed on the first, second and third sides of each of the drug-loaded filament strands to enable drug elution along the fourth side at the treatment site.

12. The drug-delivery stent delivery system of claim 3, wherein the plurality of individual filament strands are configured to assume a cross-sectional design from the group comprising rectangular, circular, oval, triangular, trapezoidal, and tubular designs.

13. The drug-delivery stent delivery system of claim 3, wherein the plurality of individual filament strands are fabricated using at least two separate therapeutic drug combinations for the release thereof at the treatment site.

14. The drug-delivery stent delivery system of claim 3, wherein the plurality of individual filament strands are fabricated from a polymeric material selected from the group consisting of PMMA, EVAL, PBMA, PGA, PLLA, and copolymers and blends thereof.

15. The drug-delivery stent delivery system of claim 3, wherein the plurality of individual filament strands are fabricated from a porous metal having a polymeric drug release layer disposed thereon.

16. The drug-delivery stent delivery system of claim 3, wherein the individual filament strands are fabricated from a micron- to nano-scale level.

17. A drug-delivery stent delivery system for controlled release of therapeutic drugs and for delivery of the therapeutic drugs in localized drug therapy in a blood vessel, comprising:

a pattern of struts interconnected to form a structure that contacts the walls of a body lumen to maintain the patency of the vessel, wherein a polymeric sleeve, fabricated as a prepatterned tube, is loaded with at least one therapeutic drug for the release thereof at a treatment site, the polymeric sleeve being attached to at least a portion of an inside surface area of the stent structure.

18. The drug-delivery stent delivery system of claim 17, wherein the drug-delivery stent delivery system is configured to treat vulnerable plaque lesions.

19. The drug-delivery stent delivery system of claim 17, wherein the drug-delivery stent delivery system is configured to treat bifurcated lesions.

20. The drug-delivery stent delivery system of claim 17, wherein the drug-delivery stent delivery system is configured for use in coronary, peripheral and vascular applications.

21. A method of making a drug-delivery stent delivery system for controlled release of therapeutic drugs and for delivery of the therapeutic drugs in localized drug therapy in a blood vessel, comprising:

providing a pattern of struts interconnected to form a structure that contacts the walls of the body lumen to maintain the patency of the vessel;

positioning a plurality of individual filament strands longitudinally across an outside surface of the stent structure in a spaced apart orientation; and

attaching the plurality of individual filament strands to the outside surface of the stent structure; and

loading the plurality of individual filament strands with at least one therapeutic drug for the release thereof at a treatment site.