Biodegradable supporting device

Abstract

A biodegradable in vivo supporting device is disclosed. In one embodiment, a coated stent device includes a biodegradable metal alloy scaffold made from a magnesium alloy, iron alloy, zinc alloy, or combination thereof, and the metal scaffold comprises a plurality of metal struts. The metal struts are at least partially covered with a biodegradable polymer coating. A method for making and a method for using a biodegradable in vivo supporting device are also disclosed.

What is claimed is: 
     
         1 . A biodegradable in vivo supporting device, comprising:
 a biodegradable metal alloy scaffold comprising a plurality of metal struts; and   a biodegradable polymer coating at least partially covering the metal struts.   
     
     
         2 . The device of  claim 1 , wherein the metal struts have an average cross-sectional thickness between 100-200 μm, the polymer coating has a thickness between 10-100 μm. 
     
     
         3 . The device of  claim 1 , wherein the biodegradable metal alloy scaffold comprises a magnesium alloy, an iron alloy, a zinc alloy, or combination thereof. 
     
     
         4 . The device of  claim 3 , wherein the alloy further comprises one or more metals selected from the group consisting of manganese, magnesium, neodymium, cerium, iron, zinc, palladium, cobalt, aluminum, tungsten, boron, carbon, sulfur, silicon, lithium, zirconium, calcium, and yttrium. 
     
     
         5 . The device of  claim 1 , wherein the metal alloy further comprises at least one rare earth metal and a majority of the metal alloy comprises magnesium. 
     
     
         6 . The device of  claim 5 , wherein the rare earth metal is neodymium or cerium. 
     
     
         7 . The device of  claim 1 , wherein the biodegradable metal scaffold is made from a magnesium alloy having at least 96 wt. % of magnesium, at least 1 wt. % of manganese, and at least 0.5 wt. % of a rare earth metal. 
     
     
         8 . The device of  claim 7 , wherein the biodegradable metal scaffold is made from a magnesium alloy having a magnesium content of 96-97.9 wt. %, a manganese content of 1.6-2 wt. %, and rare earth metal content of 0.5-2 wt. %. 
     
     
         9 . The device of  claim 7 , wherein the biodegradable metal scaffold is made from a magnesium alloy having a magnesium content of 97.45 wt. %, a manganese content of 1.8 wt. %, and a neodymium content of 0.75 wt. %. 
     
     
         10 . The device of  claim 1 , wherein the biodegradable metal scaffold is an expandable scaffold. 
     
     
         11 . The device of  claim 1 , wherein the metal scaffold is less than 60% w/w or less than 60% v/v of the device. 
     
     
         12 . The device of  claim 1 , wherein the biodegradable polymer coating is permeable to body fluid. 
     
     
         13 . The device of  claim 1 , wherein the biodegradable polymer comprises PLLA, PLGA, or a combination thereof. 
     
     
         14 . The device of  claim 1 , wherein the biodegradable polymer coating has one or more holes allowing direct contact between the metal struts and body fluids when the stent device is placed inside a body lumen. 
     
     
         15 . The device of  claim 1 , wherein the biodegradable polymer coating comprises an anti-proliferative agent selected from the group consisting of paclitaxel, sirolimus, docetaxel, biolimus A9, zotarolimus, everolimus, myolimus, novolimus, pimecrolimus, tacrolimus, ridaforolimus, temsirolimus and combination thereof. 
     
     
         16 . The device of  claim 1 , further comprising an additional coating between the metal alloy scaffold and the biodegradable coating that delays the degradation time of the metal alloy scaffold. 
     
     
         17 . The device of  claim 16 , wherein the additional coating is a nano-coating of iron. 
     
     
         18 . A biodegradable in vivo supporting device, comprising:
 a biodegradable metal alloy scaffold made from a magnesium alloy, an iron alloy, a zinc alloy, or combination thereof, the metal scaffold comprising a plurality of metal struts;   a biodegradable polymer coating at least partially covering the metal struts,   wherein the metal struts have an average cross-sectional thickness between 100-200 μm, the polymer coating has a thickness between 10-100 μm.   
     
     
         19 . A biodegradable in vivo supporting device, comprising:
 a biodegradable metal alloy scaffold made from a magnesium alloy having a magnesium content of 97.45 wt. %, a manganese content of 1.8 wt. %, and a neodymium or cerium content of 0.75 wt. %, the metal scaffold comprising a plurality of metal struts;   a biodegradable polymer coating at least partially covering the metal struts,   wherein the metal struts have an average cross-sectional thickness between 100-200 μm, the polymer coating has a thickness between 10-100 μm.   
     
     
         20 . A method for treating a condition in a subject with a biodegradable in vivo supporting device, comprising:
 establishing an entry portal into a body lumen in a subject in need of such treatment; and   delivering said supporting device to a target location through said body lumen; and   deploying said supporting device at the target location,   wherein said biodegradable in vivo supporting device comprises a biodegradable metal alloy scaffold comprising a plurality of metal struts and a biodegradable polymer coating at least partially covering the metal struts.   
     
     
         21 . The method of  claim 20 , wherein said body lumen is a blood vessel. 
     
     
         22 . The method of  claim 21 , wherein said blood vessel is a cardiac blood vessel. 
     
     
         23 . The method of  claim 22 , wherein the metal struts have an average cross-sectional thickness between 100-200 μm, the polymer coating has a thickness between 10-100 μm. 
     
     
         24 . A kit for placement of a biodegradable in vivo supporting device, comprising:
 a biodegradable in vivo supporting device comprising a biodegradable metal alloy scaffold comprising a plurality of metal struts and a biodegradable polymer coating at least partially covering the metal struts, and   a guide wire.