DRUG-COATED BALLOON CATHETER AND METHOD FOR THE PRODUCTION THEREOF

1 . A drug-coated balloon catheter having a balloon, comprising:

(i) a main membrane, and

(ii) an asymmetrical polymer membrane which is applied to an outside of the main membrane and into which at least one pharmaceutical active ingredient is embedded.

2 . The catheter according to claim 1 , wherein the main membrane comprises a polymer material at least on the side thereof facing the polymer membrane.

3 . The catheter according to claim 2 , wherein the polymer material of the main membrane is selected from the group consisting of polyurethane, polyether-polyurethane, polyethylene terephthalate, polybutylene terephthalate, polyamide, and copolymers and blends thereof.

4 . The catheter according to claim 3 , wherein the polymer material of the main membrane is polyamide.

5 . The catheter according to claim 1 , wherein the polymer membrane comprises polyurethane or polyether-polyurethane.

6 . The catheter according to claim 1 , wherein at least one pharmaceutical active ingredient is embedded into the polymer membrane.

7 . A method for producing a drug-coated balloon catheter, comprising the following steps:

a) providing a balloon blank having a main membrane;

b) wetting the main membrane with a homogeneous polymer solution comprising a solvent and a polymer;

c) inducing a phase separation of the polymer from the polymer solution by a measure selected from the group consisting of:

(i) Temperature change,

(ii) immersing the wetted balloon blank in a bath of a liquid which can be mixed with the solvent of the polymer solution, but which does not dissolve, or hardly dissolves, the polymer, and

(iii) exposing the wetted balloon blank to an atmosphere which comprises a gaseous constituent which can be mixed with the solvent of the polymer solution, but does not dissolve, or hardly dissolves, the polymer.

8 . The method according to claim 7 , wherein step c) is carried out in an expanded state of the balloon blank.

9 . The method according to claim 8 , wherein the polymer solution comprises a pharmaceutical active ingredient.

10 . The method according to claim 7 , wherein the balloon is dried after the phase separation, and subsequently a pharmaceutical active ingredient is embedded by applying an active ingredient solution, or a pure active ingredient, onto the polymer membrane in the expanded state of the balloon blank.

11 . The method according to claim 7 , wherein the main membrane of the balloon comprises polyamide at least on the side thereof facing the polymer membrane, and the polymer solution is a solution of polyurethane or polyether-polyurethane in tetrahydrofurane (THF) or dimethylformamide (DMF).