Stent having active release reservoirs

Abstract

Devices for the controlled release of one or more drugs are provided. The devices include an implantable stent, at least two reservoirs in the stent, and a release system contained in each of the at least two reservoirs, wherein the release system comprises one or more drugs for release.

1 . A system for controlled delivery of a drug comprising:
 a substrate positioned on an implantable delivery device;   at least two reservoirs in the substrate, each reservoir defining an opening;   at least one therapeutic agent disposed in each of the reservoirs;   a reservoir cap sealing each opening;   a mechanical rupturing mechanism configured to produce sonic waves that rupture the reservoir cap to permit release of the therapeutic agent from the reservoir through the opening; and   a mixing chamber adjacent the reservoirs, wherein upon release of the therapeutic agent from at least one of the reservoirs, the therapeutic agent is combined with a carrier fluid in the mixing chamber and then transported to a delivery site in a patient.   
     
     
         2 . The system of  claim 1 , wherein the mechanical rupturing mechanism comprises a piezoelectric material. 
     
     
         3 . The system of  claim 2 , wherein the piezoelectric material comprises any material having a crystal structure that is non-centrosymmetric. 
     
     
         4 . The system of  claim 2 , wherein the piezoelectric material comprises a ceramic material. 
     
     
         5 . The system of  claim 2 , wherein the piezoelectric material comprises a polymer. 
     
     
         6 . The system of  claim 1 , wherein the mechanical rupturing mechanism is positioned on the implantable delivery device. 
     
     
         7 . The system of  claim 1 , wherein the mechanical rupturing mechanism is positioned outside of the implantable delivery device. 
     
     
         8 . The system of  claim 1 , wherein the reservoir cap comprises a thin film formed of a metal, a polymer, or a combination thereof. 
     
     
         9 . The system of  claim 1 , wherein the therapeutic agent is in a matrix formed of degradable material or a material which releases the therapeutic agent by diffusion out of or disintegration of the matrix. 
     
     
         10 . The system of  claim 1 , wherein the implantable delivery device is a stent.