Composition and method of preparation of protease microparticulate slow release preparation

Abstract

Compositions containing microparticles loaded with one or protease enzymes and optionally auxiliary therapeutic agents and methods of treating conditions such as keloids therewith are disclosed. The biodegradable polymer and the protease enzyme therein form a controlled release matrix for extended release of the enzyme after administration to a mammal in need thereof.

1 . A composition, comprising a plurality of biodegradable polymer microparticles comprising a protease enzyme therein, the biodegradable polymer and the protease enzyme forming a controlled release matrix for extended release of the enzyme; wherein the plurality of microparticles include a mixture of microparticles containing different proteases. 
     
     
         2 . The composition of  claim 1 , wherein the protease is selected from the group consisting of collagenase, papain, elastase and mixtures thereof. 
     
     
         3 . The composition of  claim 1 , wherein the biodegradable polymer wherein the biodegradable polymer is selected from the group consisting of polylactic acid (PLA), polylactic co-glycolic acid (PLGA), polyglycolic acid (PGA) polylactones, polyorthocarbonate, polyhydroxybutyrate, polyalkylcyanoacrylates, polyanhydrides, polyorthoesters, polyester, polyimide, polyglycolides (PGA), polyorthoester, polyacetates, polystyrene, polycarbonates, polysaccharides, polycaprolactone, L-polylactides, block co-polymers of polyesters and linear or star-polyethyleneglycol, poly-beta-hydroxybutyrate, beta-hydroxyvalerate-copolymers, polyaminoacids, hydrophobized hyaluronic acid, dextrans, starches, methyl methacrylate, acrylamide, bisacrylamide, albumin, cellulose, cellulose-based polymers, chitosan, collagen, gelatin, proteins, Polyvinyl alcohol (PVA), polyvinylpyrrolidone, polyvinylpyridine, and ethylene glycol polymers. 
     
     
         4 . The composition of  claim 3 , wherein the biodegradable polymer is polylactic co-glycolic acid or polylactic acid. 
     
     
         5 . The composition of  claim 4 , wherein the biodegradable polymer is poly lactide-poly glycolide polymer copolymer (PLGA). 
     
     
         6 . The composition of  claim 5 , wherein the PLGA has a molecular weight of from about 7,000 to about 100,000. 
     
     
         7 . The composition of  claim 1 , wherein the microparticles have a cross-sectional diameter of from about 10 nm to about 100 μm. 
     
     
         8 . The composition of  claim 7 , wherein the microparticles have a cross-sectional diameter of from about 100 nm to about 50 μm. 
     
     
         9 . The composition of  claim 8 , wherein the microparticles have a cross-sectional diameter of from about 1 μm to about 20 μm. 
     
     
         10 . The composition of  claim 1 , wherein the percent loading of the protease in the microparticles is from about 0.1 to about 5.0. 
     
     
         11 . The composition of  claim 10 , wherein the protease is collagenase and the percent loading of the protease in the microparticles is from about 3 to about 5%. 
     
     
         12 . The composition of  claim 10 , wherein the protease is elastase and the percent loading of the protease in the microparticles is from about 0.1 to about 0.6%. 
     
     
         13 . The composition of  claim 10 , wherein the protease is papain and the percent loading of the protease in the microparticles is from about 0.5 to about 0.9. 
     
     
         14 . A composition according to  claim 2 , comprising a first portion of microparticles containing collagenase, and a second portion of microparticles containing papain or elastase. 
     
     
         15 . A composition according to  claim 2 , comprising a first portion of microparticles containing collagenase, a second portion of microparticles containing papain and a third portion of microparticles containing elastase. 
     
     
         16 . The composition of  claim 1 , further comprising an auxiliary therapeutic agent dissolved or dispersed within the controlled release matrix. 
     
     
         17 . The composition of  claim 16 , wherein the auxiliary therapeutic agent is co-mingled with the microparticles in the composition. 
     
     
         18 . The composition of  claim 16 , wherein the auxiliary therapeutic agent is a steroidal or a non-steroidal inflammation reducing agent. 
     
     
         19 . The composition of  claim 18 , wherein the steroidal inflammation reducing agent is dexamethasone. 
     
     
         20 . A method of treating hypertrophic scars (or tissue) in a mammal, comprising administering an effective amount of a composition of  claim 1  to a mammal in need thereof. 
     
     
         21 . The method of  claim 20 , wherein said hypertrophic scar is a keloid. 
     
     
         22 . The method of  claim 20 , wherein the administering is carried out by injecting the composition to an area requiring said treatment or by topically applying the composition to an area requiring said treatment. 
     
     
         23 . The method of  claim 20 , wherein the composition is administered once a week, once a month or once every two months.