Polymeric synthetic antidote

1. A polymer of formula (I):

where X 1 and X 2 respectively represent the alpha and omega end groups of the polymer;

R 1 represents a hydrogen atom or a straight or branched chain alkyl group from 1 to 6 carbon atoms;

R 2 represents a straight or branched chain alkyl group which is substituted by a group which has a positive charge at a physiological pH; and

n is an integer having a value from 6 to 130;

or a copolymer thereof;

for use as a medicament;

wherein X 1 and X 2 represent a hydrogen atom, a hydroxyl group, an ethyl isobutyrate group, an alkyl group, an halogen group, a carboxylic acid group, an amino group or a methoxy or an ethoxy group.

2. The polymer according to claim 1 , Wherein R 2 represents a straight or branched chain alkyl group comprising from 1 to 10 carbon atoms.

3. The polymer according to claim 1 , wherein the substituent of R 2 has a positive charge at pH 7.4; and the substituent of R 2 is a group of formula —N(R 3 ) 2 wherein R 3 is the same or different and represents a hydrogen atom or a straight or branched chain alkyl group from 1 to 6 carbon atoms.

4. The polymer according to claim 1 , wherein the polymer is a co-polymer.

5. The polymer according to claim 4 , wherein the co-polymer has a linear, dendritic, or grafted structure.

6. The polymer according to claim 4 , wherein the co-polymer comprises a repetitive unit Which is one or more of an ethylene glycol, an acrylate, a methacrylate, optionally carrying a polyethylene oxide (PEO), or a unit —(CH 2 —C(R 1 )(C(O)OR 4 ))— where R 4 represents a straight or branched chain alkyl group substituted by a group —N + (R 3 ) 3 .

7. The polymer according to claim 1 , which is a polymer of formula (IV):

where X 1 , X 2 , R 1 , R 2 and n are as defined in claim 1 ; and X 3 represents an anion, for example OH − ; Cl − ; HCO 3 − ; NO 3 − ; H 2 PO 4 − .

8. The polymer according to claim 1 , Which is in lyophilisate form.

9. The polymer according to claim 1 , which has a mean charge density of from 20 to 80%.

10. The polymer according to claim 9 , which has a mean charge density from 15 to 30%.

11. The polymer according to claim 1 , which has a molecular weight from 4000 to 10000 g/mol.

12. The polymer according to claim 1 which comprises a repetitive unit which is N,N dimethyl amino ethyl methacrylate.

13. The polymer according to claim 12 which is polydimethyl amino ethyl methacrylate.

14. A method for treatment of a heparin overdose and/or for neutralisation of anticoagulation comprising the step of administering the polymer according to claim 1 to a subject.

15. A pharmaceutical composition comprising a polymer of formula (I) as claimed in claim 1 and a pharmaceutically acceptable diluent for use as a medicament.

16. A method of treating a heparin overdose or for neutralising anticoagulation which method comprises a step of administering to a human or animal in need of such treatment an effective amount of a polymer of formula (I) as defined in claim 1 .

17. A method of treating a heparin overdose or for neutralising anticoagulation which method comprises a step of administering to a human or animal in need of such treatment an effective amount of a pharmaceutical composition as defined in claim 15 .

18. The polymer according to claim 1 , wherein X 1 is an ethylisobutyrate moiety, X 2 is a hydroxyl group, R 1 is a methyl group or a variant thereof, R 2 is a straight alkyl group comprising two carbon atoms substituted by a group of formula —N(R 3 ) 2 wherein R 3 represents a hydrogen atom or a straight or branched chain alkyl group having from 1 to 6 carbon atoms, n is an integer having a value from 6 to 130, X 3 is a chloride anion or a variant thereof.