Compositions for use in embolizing blood vessels

• US 5,851,508 A
• Filed: 02/14/1997
• Issued: 12/22/1998
• Est. Priority Date: 07/27/1995
• Status: Expired due to Term

• Current Assignee: Micro Therapeutics, Inc. (Medtronic Plc)
• Original Assignee: Micro Therapeutics, Inc. (Medtronic Plc)
• Inventors: Jones, Michael L., Evans, Scott, Greff, Richard J.
• Primary Examiner(s): NILAND, PATRICK DENNIS
• Application Number:
  US08/800,677
• Time in Patent Office: 676 Days
• Field of Search: 424/9.4, 424/9.41, 424/9.411, 424/78.37, 523/105, 523/113, 523/136, 524/155, 524/173, 524/408, 524/430, 524/439, 524/423, 524/436, 604/20, 604/21, 604/52, 604/53, 604/56, 604/70
• US Class Current: 424/9.411
• CPC Class Codes: A61K 49/0404 containing barium sulfate
• CPC Class Codes: A61K 49/0414 Particles, beads, capsules or spheres
• CPC Class Codes: A61L 24/001 Use of materials characterised by their function or physical properties
• CPC Class Codes: A61L 24/046 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds A61L24/043 takes precedence
• CPC Class Codes: A61L 24/06 obtained by reactions only involving carbon-to-carbon unsaturated bonds A61L24/043, A61L24/046 take precedence
• CPC Class Codes: A61L 24/08 Polysaccharides A61L24/043 takes precedence
• CPC Class Codes: A61L 2430/36 for embolization or occlusion, e.g. vaso-occlusive compositions or devices artificial blood vessels A61L27/507
• CPC Class Codes: C08L 29/04 Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids

Abstract

Disclosed are compositions suitable for use in embolizing blood vessels which compositions comprise an ethylene vinyl alcohol copolymer, a biocompatible solvent and a water insoluble contrasting agent selected from the group consisting of tantalum, tantalum oxide and barium sulfate. Also disclosed are methods for embolizing a blood vessel using the compositions described herein.

Claims

1. A composition comprising:

(a) from about 2.5 to about 8.0 weight percent of an ethylene vinyl alcohol copolymer;

(b) from about 20 to about 40 weight percent of a water insoluble contrast agent selected from the group consisting of tantalum, tantalum oxide and barium sulfate;

(c) from about 52 to about 87.5 weight percent of a biocompatible solvent

wherein the weight percent of each of the components is based on the total weight of the complete composition.

2. The composition according to claim 1 wherein said ethylene vinyl alcohol copolymer comprises from about 25 to about 60 mole percent of ethylene and from about 40 to about 75 mole percent of vinyl alcohol.

3. The composition according to claim 2 wherein said biocompatible solvent is DMSO.

4. The composition according to claim 3 wherein said contrast agent is tantalum.

5. The composition according to claim 3 wherein said contrast agent is tantalum oxide.

6. The composition according to claim 3 wherein said contrast agent is barium sulfate.

7. A method for embolizing a blood vessel by injecting into said blood vessel a sufficient amount of an embolizing composition comprising:

(a) from about 2.5 to about 8.0 weight percent of an ethylene vinyl alcohol copolymer embolizing agent;

(b) from about 20 to about 40 weight percent of a water insoluble contrast agent selected from the group consisting of tantalum, tantalum oxide and barium sulfate;

(c) from about 52 to about 87.5 weight percent of a biocompatible solvent

wherein the weight percent of each of the components is based on the total weight of the complete composition

under conditions wherein a precipitate is formed which embolizes the blood vessel.

8. The method according to claim 7 wherein said ethylene vinyl alcohol copolymer comprises from about 25 to about 60 mole percent of ethylene and from about 40 to about 75 mole percent of vinyl alcohol.

9. The method according to claim 8 wherein said biocompatible solvent is DMSO.

10. The method according to claim 9 wherein said contrast agent is tantalum.

11. The method according to claim 9 wherein said contrast agent is tantalum oxide.

12. The method according to claim 9 wherein said contrast agent is barium sulfate.

13. The method according to claim 7 wherein the embolizing composition is injected into the blood vessel at a rate of about 0.05 to 0.3 cc/minute.

14. The method according to claim 7 wherein the embolizing composition is injected into the blood vessel at a rate of at least 0.6 cc/minute.

15. The method according to claim 14 wherein the injection rate of at least 0.6 cc/minute is employed to form a filament like mass projecting down stream from the catheter tip for embolizing tumor masses, organs and arteriovenous malformations (AVM).