Growth factor delivery system for the healing of wounds and the prevention of inflammation and disease

Abstract

The present invention features hydrogel drug delivery systems and methods of producing and using such systems for the treatment of wounds. The systems are based on a hydrogel into which a low concentration of growth factor, e.g., epidermal growth factor, is passively transferred from a dilute aqueous solution. When placed in contact with a wounded tissue, the growth factor passively transfers out of the contact lens to provide accelerated healing. The amount of growth factor absorbed into the hydrogel is low, e.g., ≦350 ppb, but this amount has surprisingly been found to be effective in producing a therapeutic effect. The systems are applicable to ocular and other wound treatments.

What is claimed is:  
     
         1 . A polymeric hydrogel that comprises a substantially pure growth factor at a concentration of between 5 ppb and 350 ppb.  
     
     
         2 . The hydrogel of  claim 1 , wherein said growth factor is selected from the group consisting of epidermal growth factor, platelet derived growth factor, hepatocytic growth factor, and combinations thereof.  
     
     
         3 . The hydrogel of  claim 2 , wherein said growth factor is epidermal growth factor.  
     
     
         4 . The hydrogel of  claim 1 , said hydrogel comprising a water content between 37.5% and 70% by weight.  
     
     
         5 . The hydrogel of  claim 1 , said hydrogel comprising a tetrapolymer of hydroxymethylmethacrylate, ethylene glycol, dimethylmethacrylate, and methacrylic acid.  
     
     
         6 . The hydrogel of  claim 1 , wherein said growth factor is capable of being passively released into an environment under ambient conditions.  
     
     
         7 . The hydrogel of  claim 6 , wherein said environment is an ocular environment.  
     
     
         8 . The hydrogel of  claim 1 , wherein said growth factor is capable of being passively released into an environment under existing conditions.  
     
     
         9 . The hydrogel of  claim 8 , wherein said environment is an ocular environment.  
     
     
         10 . The hydrogel of  claim 1 , wherein said hydrogel is shaped as a contact lens.  
     
     
         11 . The hydrogel of  claim 10 , wherein said hydrogel is capable of correcting vision.  
     
     
         12 . The hydrogel of  claim 11 , wherein said hydrogel is capable of correcting vision in the range of +8.0 to −8.0 diopters, including plano.  
     
     
         13 . The hydrogel of  claim 10 , said hydrogel having a base curve between 8.0 and 9.0.  
     
     
         14 . The hydrogel of  claim 1 , said hydrogel comprising an ionic polymer.  
     
     
         15 . The hydrogel of  claim 1 , said hydrogel comprising a non-ionic polymer.  
     
     
         16 . The hydrogel of  claim 1 , said hydrogel comprising etafilcon A, vifilcon A, or polymacon B.  
     
     
         17 . A method for making a hydrogel drug delivery system, said method comprising the steps of: 
 (a) providing a hydrogel;    (b) washing the hydrogel in an isotonic saline solution;    (c) partially desiccating the lens; and    (d) placing the washed and partially desiccated hydrogel in an aqueous solution of between 0.01 and 10 ng growth factor per μl, 
 wherein growth factor is passively transferred into said hydrogel to produce said hydrogel drug delivery system.  
   
     
     
         18 . The method of  claim 17 , wherein the concentration of growth factor in said hydrogel after step (d) is between 5 and 350 ppb.  
     
     
         19 . The method of  claim 17 , wherein said growth factor is selected from the group consisting of epidermal growth factor, platelet derived growth factor, hepatocytic growth factor, and combinations thereof.  
     
     
         20 . The method of  claim 19 , wherein said growth factor is epidermal growth factor.  
     
     
         21 . The method of  claim 17 , wherein said aqueous solution in step (d) has a pH between 6.9 and 7.4  
     
     
         22 . The method of  claim 17 , wherein said hydrogel is shaped as a contact lens.  
     
     
         23 . The method of  claim 17 , wherein, in step (d), said hydrogel is placed in said solution for at least 30 minutes.  
     
     
         24 . A method for treating a wound, said method comprising the steps of: 
 (a) providing a polymeric hydrogel comprising between 5 and 350 ppb by weight of growth factor; and    (b) placing said hydrogel in contact with said wound, 
 wherein said growth factor is passively released from said hydrogel to treat said wound.  
   
     
     
         25 . The method of  claim 24 , wherein said growth factor is selected from the group consisting of epidermal growth factor, platelet derived growth factor, hepatocytic growth factor, and combinations thereof.  
     
     
         26 . The method of  claim 25 , wherein said growth factor is epidermal growth factor.  
     
     
         27 . The method of  claim 24 , wherein said wound is in an eye and said hydrogel is shaped as a contact lens.  
     
     
         28 . The method of  claim 24 , wherein said hydrogel further acts as a protective shield against mechanical abuse.  
     
     
         29 . The method of  claim 24 , wherein said wound is in endothelial tissue.  
     
     
         30 . The method of  claim 24 , wherein said wound is in epithelial tissue.  
     
     
         31 . The method of  claim 24 , wherein said wound is a lung, skin, or digestive tract wound.  
     
     
         32 . The method of  claim 24 , wherein, in step (b), the hydrogel is placed in a body cavity.  
     
     
         33 . The method of  claim 24 , wherein said passively released growth factor causes a reduction in pain compared to a wound not contacted with said polymeric hydrogel.