Medical devices having nanoporous coatings for controlled therapeutic agent delivery

Abstract

According to an aspect of the present invention, implantable or insertable medical devices are provided which contain (a) one or more depressions that contain at least one therapeutic agent, and (b) a nanoporous coating, disposed over the therapeutic-agent-containing depressions, which regulate transport of species between the therapeutic-agent-containing depressions and the exterior of the device. The implantable or insertable devices are configured to preform a role beyond mere drug delivery, for example, providing mechanical and/or electrical functions within the body, among other functions. An advantage of the present invention is that medical devices may be provided, which release therapeutic agents in quantities far exceeding the void volume within the nanoporous coating, while at the same time providing functionality that extends beyond drug delivery. Such release may further approach or achieve a zero order kinetic drug release profile.

1 . An implantable or insertable medical device comprising: (a) a region comprising a depression (b) a therapeutic-agent-containing region within said depression, said therapeutic-agent-containing region comprising a first therapeutic agent, and (c) a nanoporous region disposed over the depression and regulating transport of molecular species between the depression and an exterior of the device, wherein said medical device provides a therapeutic function beyond its function as a therapeutic agent depot.  
     
     
         2 . The implantable or insertable medical device of  claim 1 , wherein said region comprises a plurality of depressions.  
     
     
         3 . The implantable or insertable medical device of  claim 1 , wherein said depression is a through-hole or a slot.  
     
     
         4 . The implantable or insertable medical device of  claim 1 , wherein said depression is a blind hole or a trench.  
     
     
         5 . The implantable or insertable medical device of  claim 1 , wherein the smallest lateral dimension of said depression is less than 1000 μm.  
     
     
         6 . The implantable or insertable medical device of  claim 1 , wherein the smallest lateral dimension of said depression is less than 100 μm.  
     
     
         7 . The implantable or insertable medical device of  claim 1 , wherein the depression has an aspect ratio of greater than or equal to 1.  
     
     
         8 . The implantable or insertable medical device of  claim 1 , wherein said region comprising said depression is a metallic region.  
     
     
         9 . The implantable or insertable medical device of  claim 1 , wherein said region comprising said depression is a polymeric region.  
     
     
         10 . The implantable or insertable medical device of  claim 1 , wherein said region comprising said depression is a silicon region.  
     
     
         11 . The implantable or insertable medical device of  claim 1 , wherein said region comprising said depression is a ceramic region.  
     
     
         12 . The implantable or insertable medical device of  claim 1 , wherein said nanoporous region is a nanoporous polymeric region.  
     
     
         13 . The implantable or insertable medical device of  claim 1 , wherein said nanoporous region is a nanoporous metallic region.  
     
     
         14 . The implantable or insertable medical device of  claim 1 , wherein said nanoporous region is a nanoporous ceramic region.  
     
     
         15 . The implantable or insertable medical device of  claim 14 , wherein said nanoporous ceramic region selected from a nanoporous alumina region, a nanoporous titania region, and a nanoporous silica region.  
     
     
         16 . The implantable or insertable medical device of  claim 1 , wherein said nanoporous region comprises a parallel pore structure.  
     
     
         17 . The implantable or insertable medical device of  claim 1 , wherein said nanoporous region comprises an interconnected pore structure.  
     
     
         18 . The implantable or insertable medical device of  claim 1 , wherein said therapeutic function is selected from a mechanical function, an electrical function, a thermal function and a magnetic function.  
     
     
         19 . The implantable or insertable medical device of  claim 1 , wherein said device is selected from catheters, guide wires, balloons, filters, stents, grafts, stent grafts, vascular access ports, embolization devices, myocardial plugs, patches, pacemakers, pacemaker leads, left ventricular assist devices, total artificial hearts, heart valves, vascular valves, anastomosis clips and rings, and tissue engineering scaffolds.  
     
     
         20 . The implantable or insertable medical device of  claim 1 , wherein said medical device is adapted for implantation or insertion into the coronary vasculature, peripheral vascular system, esophagus, trachea, colon, biliary tract, urogenital system, or brain.  
     
     
         21 . The implantable or insertable medical device of  claim 1 , wherein said medical device is a stent and wherein said region comprising said depression is a stent strut.  
     
     
         22 . The implantable or insertable medical device of  claim 1 , further comprising a material in addition to said first therapeutic agent within said therapeutic-agent-containing region.  
     
     
         23 . The implantable or insertable medical device of  claim 1 , further comprising a second therapeutic agent within said therapeutic-agent-containing region.  
     
     
         24 . The implantable or insertable medical device of  claim 1 , wherein said therapeutic agent is released from said device.  
     
     
         25 . The implantable or insertable medical device of  claim 24 , wherein the release is zero-order release.  
     
     
         26 . The implantable or insertable medical device of  claim 1 , wherein said therapeutic agent is selected from one or more of the group consisting of anti-thrombotic agents, anti-proliferative agents, anti-inflammatory agents, anti-migratory agents, agents affecting extracellular matrix production and organization, antineoplastic agents, anti-mitotic agents, anesthetic agents, anti-coagulants, vascular cell growth promoters, vascular cell growth inhibitors, cholesterol-lowering agents, vasodilating agents, TGF-β elevating agents, and agents that interfere with endogenous vasoactive mechanisms.