Elastomeric Copolymer Coatings For Implantable Medical Devices

Abstract

Implantable medical devices with elastomeric copolymer coatings are disclosed.

1 . An implantable medical device comprising a coating above a polymer surface of the device, the coating comprising:
 a block copolymer including an elastic block, an anchor block, and a fast degrading glassy block, the elastic block being a homopolymer and elastomeric at physiological conditions, the anchor block being miscible with the surface polymer, and the fast degrading glassy block having a faster degradation rate than the anchor block;   wherein the elastic block is selected from the group consisting of poly(caprolactone), poly(4-hydroxybutyrate), poly(dioxanone), and combinations thereof;   wherein the anchor block comprises a polymer selected from the group consisting of poly(L-lactide), poly(L-lactide-co-glycolide), and combinations thereof;   wherein the fast degrading glassy block is poly(glycolide), poly(L-lactide-co-glycolide), or a combination thereof; and   wherein the surface polymer is poly(L-lactide), poly(L-lactide-co-glycolide), or a combination thereof.   
     
     
         2 . The device of  claim 1 , wherein the device is a stent. 
     
     
         3 . The device of  claim 1 , wherein the block copolymer is biodegradable. 
     
     
         4 . The device of  claim 1 , wherein a body of the device is formed from a biodegradable polymer. 
     
     
         5 . The device of  claim 1 , wherein the block copolymer is a linear block copolymer. 
     
     
         6 . The device of  claim 1 , wherein a majority of the coating comprises the block copolymer. 
     
     
         7 . The device of  claim 1 , wherein the polymer surface comprises a surface of a substrate of the device or a surface of a coating layer above the substrate of the device. 
     
     
         8 . The device of  claim 1 , wherein the coating comprises an active agent. 
     
     
         9 . The device of  claim 1 , wherein the anchor block is of the same chemical composition as the surface polymer. 
     
     
         10 . The device of  claim 1 , wherein the anchor block and the surface polymer have a Tg above body temperature. 
     
     
         11 . An implantable medical device comprising a coating above a polymer surface of the device, the coating comprising:
 an elastomeric star copolymer having at least three arms and comprising elastic units, anchor units, and fast degrading units, the elastic units providing elastomeric properties to the copolymer at physiological conditions and the fast degrading units being glassy;   wherein the arms of the star copolymer comprise the elastic units, the fast degrading units, and the anchor units;   wherein the surface polymer is poly(1-lactide), poly(1-lactide-co-glycolide), or a combination thereof, and the anchor units comprise 1-lactide;   wherein the elastic units are caprolactone, 4-hydroxy butyrate, dioxanone, or any combination thereof; and   wherein the fast degrading units are glycolide.   
     
     
         12 . The device of  claim 11 , wherein the device is a stent. 
     
     
         13 . The device of  claim 11 , wherein the anchor units are the same as at least some units of the surface polymer. 
     
     
         14 . The device of  claim 11 , wherein the elastomeric star copolymer is a random copolymer or an alternating copolymer. 
     
     
         15 . The device of  claim 11 , wherein a body of the device is formed from a biodegradable polymer. 
     
     
         16 . The device of  claim 11 , wherein a majority of the coating comprises the star copolymer. 
     
     
         17 . The device of  claim 11 , wherein the polymer surface comprises a surface of a substrate of the device. 
     
     
         18 . The device of  claim 11 , wherein the coating comprises an active agent. 
     
     
         19 . The device of  claim 11 , wherein the polymer surface comprises a surface of a coating layer above the substrate of the device.