EXTRACTION OF SOLVENTS FROM DRUG CONTAINING POLYMER RESERVOIRS

• US 20090287300A1
• Filed: 05/19/2008
• Published: 11/19/2009
• Est. Priority Date: 05/19/2008
• Status: Active Grant

• Current Assignee: Cardinal Health Switzerland 515 GmbH (Cardinal Health, Inc.)
• Original Assignee: Cordis Corporation (Cardinal Health, Inc.)
• Inventors: Dave, Vipul, Zhao, Jonathon Z., Falotico, Robert
• Granted Patent: US 8,273,404 B2
• Time in Patent Office: Days
• US Class Current: 623/1.420
• CPC Class Codes: A61L 2300/416 Anti-neoplastic or anti-proliferative or anti-restenosis or anti-angiogenic agents, e.g. paclitaxel, sirolimus
• CPC Class Codes: A61L 2300/606 Coatings
• CPC Class Codes: A61L 31/06 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds A61L31/041 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 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence

Abstract

A process for reducing solvent contents in drug-containing polymeric compositions may be utilized to reduce the solvent content in implantable medical device wherein the compositions are in reservoirs. Specifically, the solvent contents in the drug-containing polymeric compositions are first reduced by one or more conventional drying methods, to a range from about 0.5 weight percent to about 10 weight percent of the total weight of the polymeric composition. Subsequently, the drug-containing polymeric compositions are further treated by a low temperature drying method for further reduction of the solvent content.

Claims

1. A method for extracting solvents from a polymeric/therapeutic agent matrix contained within reservoirs of a medical device comprising exposing the medical device to carbon dioxide at a pressure in the range from about sixty bar to about eighty bar at a temperature in the range from about thirty to about forty degrees C. for a time period in the range from about five minutes to about sixty minutes.

2. The method for extracting solvents according to claim 1, wherein the medical deice comprises a stent having a plurality of through-holes.

3. The method for extracting solvents according to claim 1, wherein the medical device comprises a stent having a plurality of blind holes.

4. The method for extracting solvents according to claim 2, wherein the stent comprises a metallic material.

5. The method for extracting solvents according to claim 2, wherein the stent comprises a polymeric material.

6. The method for extracting solvents according to claim 3, wherein the stent comprises a metallic material.

7. The method for extracting solvents according to claim 3, wherein the stent comprises a polymeric material.

8. The method for extracting solvents according to claim 8, wherein the polymeric/therapeutic agent matrix comprises a bioabsorbable polymer and a rapamycin, its analogs or derivatives.

9. The method for extracting solvents according to claim 8, wherein the polymeric/therapeutic agent matrix comprises PLGA and sirolimus.

10. A method for extracting solvents from a polymeric/therapeutic agent composition contained within reservoirs of the stent comprising:

heating the stent for a predetermined period of time to dry the polymeric/therapeutic agent composition; and

exposing the stent to carbon dioxide at a pressure of sixty bar for eight minutes at a temperature of thirty-six degrees.

11. The method for extracting solvents according to claim 10, wherein the predetermined heating time is in the range from about twelve hours to about twenty-four hours.

12. The method for extracting solvents according to claim 11, wherein the porosity of the polymeric/therapeutic agent composition is controllable by varying the drying time.