Complex polymere amphiphile-PDGF

Abstract

Physically and chemically stable, water-soluble, amphiphilic polymer-PDGF complex, characterized in that the amphiphilic polymers include a hydrophilic polymeric backbone functionalized with hydrophobic substituents and hydrophilic groups.

1 . Physically and chemically stable, water-soluble, amphiphilic polymer-PDGF complex, characterized in that:
 the amphiphilic polymers consist of a hydrophilic polymeric backbone functionalized with hydrophobic substituents and hydrophilic groups according to the following general formula:   
     
       
         
         
             
             
         
       
       
         R and R′ being a bond or a chain comprising between 1 and 18 carbons, optionally branched and/or unsaturated comprising one or more heteroatoms, such as O, N and/or S, 
       
       R and R′ being identical to or different from one another,
 F and F′ being an ester, a thioester, an amide, a carbonate, a carbamate, an ether, a thioether, an amine, 
 
       F and F′ being identical to or different from one another,
 X being a hydrophilic group that may be: 
 a carboxylate 
 a sulphate 
 a sulphonate 
 a phosphate 
 a phosphonate, 
 Y being a hydrophilic group that may be: 
 a sulphate 
 a sulphonate 
 a phosphate 
 a phosphonate, 
 Hy being a hydrophobic group that may be: 
 a C 8  to C 30  linear or branched alkyl, optionally unsaturated and/or containing one or more heteroatoms, such as O, N or S, 
 a C 8  to C 18  linear or branched alkylaryl or arylalkyl, optionally unsaturated and/or optionally containing a heteroatom, 
 an optionally unsaturated C 8  to C 30  polycycle, 
 
       n and o are between 1 and 3, 
       h represents the molar fraction of hydrophobic unit relative to a monomeric unit of between 0.01 and 0.5, 
       x represents the molar fraction of hydrophilic groups relative to a monomeric unit, of between 0 and 2.0, 
       y represents the molar fraction of hydrophilic groups relative to a monomeric unit, of between 0 and 0.5;
 the PDGF is chosen from the group of PDGFs (platelet-derived growth factors). 
 
     
   
   
       2 . Complex according to  claim 1 , characterized in that the PDGF is chosen from the group consisting of human recombinant PDGFs containing two B chains (rhPDGF-BB). 
   
   
       3 . Complex according  claim 1 , characterized in that the polymer is chosen from polymers in which the substituents are distributed randomly. 
   
   
       4 . Complex according  claim 1 , characterized in that the amphiphilic polymer is chosen from polyamino acids. 
   
   
       5 . Complex according to  claim 4 , characterized in that the polyamino acids are chosen from the group consisting of polyglutamates or polyaspartates. 
   
   
       6 . Complex according to  claim 5 , characterized in that the polyamino acids are homopolyglutamates. 
   
   
       7 . Complex according to  claim 6 , characterized in that the polyamino acids are homopolyaspartates. 
   
   
       8 . Complex according to  claim 7 , characterized in that the polyamino acids are copolymers of aspartate and of glutamate. 
   
   
       9 . Complex according to  claim 1 , characterized in that the polymer is chosen from polysaccharides. 
   
   
       10 . Complex according to  claim 9 , characterized in that the polysaccharides are chosen from the group consisting of hyaluronans, alginates, chitosans, galacturonans, chondroitin sulphate, dextrans and celluloses. 
   
   
       11 . Complex according to  claim 10 , characterized in that the group of celluloses consists of celluloses functionalized with acids, such as carboxymethylcellulose. 
   
   
       12 . Complex according to  claim 10 , characterized in that the group of dextrans consists of dextrans functionalized with acids, such as carboxymethyl dextran. 
   
   
       13 . Complex according to  claim 9 , characterized in that the polysaccharides are chosen from the group consisting of hyaluronans, alginates and chitosans. 
   
   
       14 . Complex according to  claim 9 , characterized in that the polysaccharides are chosen from the group consisting of soluble dextran derivatives corresponding to formula (I) below:
   DMC a B b Su c   (I)   
     in which:
 D represents a polysaccharide chain, preferably consisting of series of glucoside units, 
 MC represents methylcarboxylic groups, 
 B represents N-benzylmethylenecarboxamide groups, 
 Su represents sulphate groups (sulphation of the free hydroxyl functions borne by the glucoside units), 
 a, b and c represent the degree of substitution (ds), respectively, of the groups MC, B and Su, with 
 i) a strictly greater than 0; 
 ii) b is such that:
 either b is greater than or equal to 0.3 and c is between 0.1 and 0.5; 
 or b is strictly less than 0.3 and c corresponds to equation (1) below:
   c≧8.5b 2 −5.41b+0.86  (1). 
 
 
 
   
   
       15 . Complex according  claim 1 , characterized in that the hydrophobic group Hy is chosen from the group consisting of fatty acids, fatty alcohols, fatty amines, benzyl amines, cholesterol derivatives and phenols. 
   
   
       16 . Complex according  claim 1 , characterized in that the formation of the amphiphilic polymer-PDGF complex is reversible. 
   
   
       17 . Complex according  claim 1 , characterized in that it passes the tests for demonstration of the chemical and physical stabilization. 
   
   
       18 . Complex according to  claim 17 , characterized in that the tests for demonstration of the chemical and physical stabilization are chosen from the group consisting of the test for demonstration of the complex (Gel Mobility Shift Assay), the test for slowing down of the enzymatic degradation by bringing into contact with a protease and the test for physical stabilization at physiological pH carried out by SDS-Page. 
   
   
       19 . Complex according to  claim 1 , characterized in that the PDGF/amphiphilic polymer ratio is between 1/5 and 1/5000. 
   
   
       20 . Complex according to  claim 1 , characterized in that the PDGF/amphiphilic polymer ratio is between 1/100 and 1/5000. 
   
   
       21 . Complex according to  claim 1 , characterized in that the PDGF/amphiphilic polymer ratio is between 1/300 and 1/700. 
   
   
       22 . Method of preparing the amphiphilic polymer/PDGF complex according to  claim 1 , characterized in that this polymer/PDGF-BB complex is prepared in aqueous media and in the absence of any organic solvent that may denature the protein. 
   
   
       23 . Therapeutic composition, characterized in that it comprises an amphiphilic polymer-PDGF complex according to  claim 1 . 
   
   
       24 . Therapeutic composition according to  claim 20 , characterized in that it allows an administration of 100 μg per ml of PDGF. 
   
   
       25 . Use of an amphiphilic polymer-PDGF complex according to  claim 1 , for the preparation of a therapeutic composition with healing action, for use in the treatment of ulcers by topical application. 
   
   
       26 . Method of therapeutic treatment for human or veterinary use, characterized in that it consists in administering, at the site of treatment, a therapeutic composition comprising an amphiphilic polymer-PDGF complex according to  claim 1