Transdermal therapeutic system for administering rivastigmine or derivatives thereof
The present invention relates to a transdermal therapeutic system for administering an active substance through the skin, comprising: a) a cover layer, b) a reservoir present on the cover layer, comprising a polymer matrix comprising the active substance, c) an adhesive layer present on the reservoir comprising a contact adhesive, and d) a removable layer present on the adhesive layer, the active substance being rivastigmine, a physiologically compatible salt, hydrate, solvate or derivative thereof, characterized in that the polymer matrix of the reservoir comprises neither hydroxyl groups nor carboxyl groups.
1. A method for preparing a transdermal therapeutic system containing rivastigmine, comprising embedding the rivastigmine or a physiologically compatible salt, hydrate, solvate or derivative thereof in a polymer matrix comprising a polymer and/or copolymer or mixture thereof, wherein said polymer and/or copolymer or mixture thereof contains neither free hydroxyl groups nor free carboxyl groups and wherein the polymer matrix contains no antioxidants.
2. The method of claim 1 , wherein said transdermal therapeutic system comprises a cover layer and wherein said step of embedding results in stabilizing the rivastigmine in the transdermal therapeutic system.
3. The method of claim 2 , wherein the polymer or copolymer is selected from the group consisting of polyacrylates, acrylate-vinyl acetate copolymers, polyisobutylene and styrene-butadiene copolymers.
4. The method of claim 2 , wherein the transdermal therapeutic system contains no antioxidants.
5. The method of claim 1 , wherein said transdermal therapeutic system comprises a cover layer and wherein said step of embedding results in reducing the break-down of the rivastigmine in the transdermal therapeutic system.
6. The method of claim 5 , wherein the polymer or copolymer is selected from the group consisting of polyacrylates, acrylate-vinyl acetate copolymers, polyisobutylene and styrene-butadiene copolymers.
7. The method of claim 5 , wherein the transdermal therapeutic system contains no antioxidants.
8. The method of claim 1 , wherein the polymer or copolymer is selected from the group consisting of polyacrylates, acrylate-vinyl acetate copolymers, polyisobutylene and styrene-butadiene copolymers.
9. The method of claim 8 , wherein the transdermal therapeutic system contains no antioxidants.
10. The method of claim 1 , wherein the transdermal therapeutic system contains no antioxidants.
11. The method of any one of claims 1 to 9 , wherein the transdermal therapeutic system comprises:
a) a cover layer,
b) a reservoir present on the cover layer, comprising the polymer matrix comprising said polymer or copolymer,
c) an adhesive layer on the reservoir comprising a contact adhesive, and
d) a removable layer present on the adhesive layer.
12. The method of claim 11 , wherein the reservoir contains 20 to 30 weight % rivastigmine and 70 to 80 weight % polymer matrix in relation to the total weight of the reservoir.
13. The method of claim 11 , wherein the adhesive layer additionally contains a gelatinizing agent and an emollient.
14. The method of claim 13 , wherein the gelatinizing agent is SiO 2 having a particle size within the range of about 400 to about 1500 nm which is in a dispersed form or in the form of pyrogenic silicic acid.
15. The method of claim 13 , wherein the emollient is paraffin, neutral oil, mineral oil or a mixture thereof.
16. The method of claim 11 , wherein the adhesive layer contains 60.0 to 74.9 weight % contact adhesive, 0.1 to 2.0 weight % gelatinizing agent and 25 to 39.9 weight % emollient in relation to the total weight of the adhesive layer.
17. The method of claim 11 , wherein the contact adhesive is polyisobutylene.
18. The method of claim 17 , wherein the polyisobutylene is a mixture of two polyisobutylene polymers of different molecular weights.
19. The method of claim 18 , wherein the first polyisobutylene polymer has a mean molecular weight Mv of approximately 40,000 g/mol, and the second polyisobutylene polymer has a mean molecular weight Mv of approximately 400,000 g/mol.
20. The method of claim 18 , wherein the weight ratio of the first polyisobutylene polymer in relation to the second polyisobutylene polymer is approximately 4:6.
21. A polymer matrix containing rivastigmine, wherein the rivastigmine or a physiologically compatible salt, hydrate, solvate or derivative thereof is embedded in a polymer matrix comprising a polymer and/or copolymer or mixture thereof and wherein said polymer and/or copolymer or mixture thereof contains neither free hydroxyl groups nor free carboxyl groups and wherein the polymer matrix contains no antioxidants.
22. A transdermal therapeutic system containing rivastigmine, wherein the rivastigmine or a physiologically compatible salt, hydrate, solvate or derivative thereof is embedded in a polymer matrix comprising polymer and/or copolymer or mixture thereof and wherein said polymer and/or copolymer or mixture thereof contains neither free hydroxyl groups nor free carboxyl groups and wherein the polymer matrix contains no antioxidants.