Medical Devices, Drug Coatings and Methods for Maintaining the Drug Coatings Thereon

Abstract

Medical devices, and in particular implantable medical devices, may be coated to minimize or substantially eliminate a biological organism's reaction to the introduction of the medical device to the organism. The medical devices may be coated with any number of biocompatible materials. Therapeutic drugs, agents or compounds may be mixed with the biocompatible materials and affixed to at least a portion of the medical device. These therapeutic drugs, agents or compounds may also further reduce a biological organism's reaction to the introduction of the medical device to the organism. Various materials and coating methodologies may be utilized to maintain the drugs, agents or compounds on the medical device until delivered and positioned.

1 . A device for intraluminal implantation in a blood vessel, said device comprising a balloon-expandable stent and a coating, said coating comprising a biocompatible polyfluoro copolymer that comprises about eighty-five weight percent vinylidinefluoride copolymerized with about fifteen weight percent hexafluoropropylene, and from about 12% to about 20% by weight of a pharmaceutical agent, wherein said pharmaceutical agent and said copolymer are selected such that said agent releases from said coating for at least 800 hours following intraluminal implantation in said blood vessel.  
   
   
       2 . The device of  claim 1  wherein said polyfluoro copolymer consists essentially of 85.5 weight percent vinylidinefluoride and 14.5 weight percent hexafluoropropylene.  
   
   
       3 . A method for preparing a device according to  claim 1 , said method comprising the steps of: 
 combining said pharmaceutical agent with said polyfluoro copolymer to provide a coating;    applying said coating to said balloon-expandable stent; and    heating the balloon-expandable stent comprising said coating to a maximum temperature of no greater than about 125° C.    
   
   
       4 . A method according to  claim 3 , wherein said balloon-expandable stent comprising said coating is heated to a maximum temperature of no greater than about 60° C.