Hydrogel co-polymer composition and its uses, for example as a wound dressing

Abstract

The present invention provides a hydrogel composition, preferably for the treatment of wounds, comprising a hydrophilic co-polymer carrying multiple pendant anionic groups, wherein the polymer is derived from a first monomer and a second monomer, wherein both monomers have an octanohwater partition coefficient Log P value of less than 0, and, the Log P value of the first monomer is greater (more positive) than the second monomer. Preferably the difference between the Log P value for the two monomers is at least 0.1, preferably at least 0.2. The difference between the Log P value for the two monomers is preferably less than 2. The weight ratio (w/w) of the first monomer/second monomer in the hydrogel composition is preferably equal to or more than about 1. The pendant anionic groups may be sulphonyl groups, e.g. sulphonic acid groups or salts thereof. The anionic group in both first and second monomers may be in salt form and the counterion for both monomers is preferably the same.

1 . A hydrogel composition for the treatment of wounds, comprising a hydrophilic co-polymer carrying multiple pendant anionic groups, wherein the polymer is derived from a first monomer and a second monomer, wherein both monomers have an octanol:water partition coefficient Log P value of less than 0, wherein the first monomer has a Log P value greater (more positive) than the second monomer and the weight ratio (w/w) of the first monomer/second monomer in the hydrogel composition is equal to or more than about 1. 
     
     
         2 . A hydrogel composition according to  claim 1 , wherein both the first and second monomers comprise a pedant anionic group in acid or salt form and, either (i) the anionic group in both first and second monomers is in acidic form or (ii) the anionic group in both first and second monomers is in salt form and the counterion for both monomers is the same. 
     
     
         3 . A hydrogel composition for the treatment of wounds, comprising a hydrophilic copolymer formed from a first monomer and a second monomer, wherein the first monomer comprises an acrylic acid ester sulphonic acid monomer or salt thereof, and the second monomer comprises an acrylamide sulphonic acid monomer or salt thereof, the weight ratio (w/w) of the first monomer/second monomer in the hydrogel is equal to or more than about 1 and, either (i) the sulphonic group in both first and second monomers is in acidic form or (ii) the sulphonic group in both first and second monomers is in salt form and the counterion for both monomers is the same. 
     
     
         4 . A hydrogel composition according to  claims 1  or  3 , wherein the first monomer is a compound of formula (I) 
       
         
           
           
               
               
           
         
       
       wherein R5 represents hydrogen or optionally substituted alkyl, preferably methyl or ethyl, R6 represents hydrogen or a cation and R7 represents an optionally substituted alkylene moiety containing 1 to 4 carbon atoms. 
     
     
         5 . A hydrogel composition according to  claim 4 , wherein the second monomer comprises a compound of formula (II) 
       
         
           
           
               
               
           
         
       
       wherein R1 is an optionally substituted hydrocarbon moiety, R2 is hydrogen or optionally substituted alkyl, and M represents hydrogen or a cation. 
     
     
         6 . A hydrogel composition according to  claim 5 , wherein the weight ratio (w/w) of the first monomer/second monomer is about 2 or more. 
     
     
         7 . A hydrogel composition according to  claim 6 , wherein the weight ratio (w/w) of the first monomer/second monomer is about 3 or more. 
     
     
         8 . A hydrogel composition according to  claim 3 , wherein both first and second monomers have a Log P value of less than 0, and the difference between Log P for the two monomers is at least about 0.1 and is less than about 2. 
     
     
         9 . A hydrogel composition according to  claim 3  for the treatment of a wound in a human or non-human mammal. 
     
     
         10 . A hydrogel composition according to  claim 9 , wherein the wound is a chronic ulcerous skin lesion. 
     
     
         11 . A hydrogel composition according to  claim 10 , wherein the wound is selected from venous leg ulcers, venous foot ulcers, arterial leg ulcers, arterial foot ulcers, decubitus ulcers (e.g. pressure sores, bedsores), post-surgical ulcerous lesions and chronic burn lesions. 
     
     
         12 . A method of treating a wound in a human or non-human mammal, comprising contacting the wound for an effective period of time with a hydrogel composition, wherein the hydrogel composition comprises
 (i) a hydrophilic co-polymer carrying multiple pendant anionic groups, wherein the polymer is derived from a first monomer and a second monomer, wherein both monomers have an octanol:water partition coefficient Log P value of less than 0, wherein the first monomer has a Log P value greater (more positive) than the second monomer and the weight ratio (w/w) of the first monomer/second monomer in the hydrogel composition is equal to or more than about 1; or   (ii) a hydrophilic copolymer formed from a first monomer and a second monomer, wherein the first monomer comprises an acrylic acid ester sulphonic acid monomer or salt thereof, and the second monomer comprises an acrylamide sulphonic acid monomer or salt thereof, the weight ratio (w/w) of the first monomer/second monomer in the hydrogel is equal to or more than about 1 and, either (i) the sulphonic group in both first and second monomers is in acidic form or (ii) the sulphonic group in both first and second monomers is in salt form and the counterion for both monomers is the same.   
     
     
         13 . A method according to  claim 12 , wherein an effective period of time promotes healing with a simultaneous reduction in one or more of: pain, exudation, malodour, excoriation, spreading of the wound, tissue necrosis, irritation and hyperkeratosis. 
     
     
         14 . (canceled) 
     
     
         15 . A method of treating skin-derived or tissue-derived pain in a human or non-human mammal, by applying to the painful area as a topical dressing a hydrogel composition, wherein the hydrogel composition comprises:
 (i) a hydrophilic co-polymer carrying multiple pendant anionic groups, wherein the polymer is derived from a first monomer and a second monomer, wherein both monomers have an octanol:water partition coefficient Log P value of less than 0, wherein the first monomer has a Log P value greater (more positive) than the second monomer and the weight ratio (w/w) of the first monomer/second monomer in the hydrogel composition is equal to or more than about 1; or   (ii) a hydrophilic copolymer formed from a first monomer and a second monomer, wherein the first monomer comprises an acrylic acid ester sulphonic acid monomer or salt thereof, and the second monomer comprises an acrylamide sulphonic acid monomer or salt thereof, the weight ratio (w/w) of the first monomer/second monomer in the hydrogel is equal to or more than about 1 and, either (i) the sulphonic group in both first and second monomers is in acidic form or (ii) the sulphonic group in both first and second monomers is in salt form and the counterion for both monomers is the same.   
     
     
         16 . (canceled) 
     
     
         17 . A method of inhibiting inflammation and/or the complement cascade and/or the kinin cascade, in a human or non-human animal patient, comprising contacting an affected location of the patient's body for an effective period of time with a hydrogel composition, wherein the hydrogel composition comprises:
 (i) a hydrophilic co-polymer carrying multiple pendant anionic groups, wherein the polymer is derived from a first monomer and a second monomer, wherein both monomers have an octanol:water partition coefficient Log P value of less than 0, wherein the first monomer has a Log P value greater (more positive) than the second monomer and the weight ratio (w/w) of the first monomer/second monomer in the hydrogel composition is equal to or more than about 1; or   (ii) a hydrophilic copolymer formed from a first monomer and a second monomer, wherein the first monomer comprises an acrylic acid ester sulphonic acid monomer or salt thereof, and the second monomer comprises an acrylamide sulphonic acid monomer or salt thereof, the weight ratio (w/w) of the first monomer/second monomer in the hydrogel is equal to or more than about 1 and, either (i) the sulphonic group in both first and second monomers is in acidic form or (ii) the sulphonic group in both first and second monomers is in salt form and the counterion for both monomers is the same.   
     
     
         18 . (canceled) 
     
     
         19 . The method of  claim 12 , wherein wound is a chronic skin lesion. 
     
     
         20 . The method of  claim 17 , wherein the inflammation and/or the complement cascade and/or the kinin cascade is a chronic skin lesion.