Highly flexible transdermal therapeutic system having nicotine as active substance
The invention relates to transdermal therapeutic systems which have the active ingredient nicotine and have particularly high flexibility. This flexibility decisively improves wearer comfort on the skin, since the system is readily capable of adapting to the surface of the skin and its constant movement. Surprisingly, the nicotine TTS of the invention is markedly more flexible than the conventional nicotine TTS products which are leaders in the market, although at least some of those systems are comparably thin.
1. A method for the manufacture of a transdermal therapeutic system with nicotine content, said system comprising
a backing layer impermeable to nicotine,
a first matrix layer immediately adjacent to the backing layer,
a second matrix layer, and
a peelable protective layer adjacent to the second matrix layer,
the total thickness of the backing layer and first and second matrix layers does not exceed 250 μm and the nicotine-content is at least 1.5 mg per cm 2 of application surface, said method comprising
coating the second matrix layer onto the peelable protective layer,
applying the first matrix layer to a portion of the second matrix layer using printing technology,
said second matrix layer forming an external margin around the first intermediate matrix layer,
mechanically laminating the backing layer onto the applied first matrix layer and the external margin formed by the second matrix layer, and
establishing nicotine equilibrium within the layers,
wherein the matrix layers do not include non-woven;
the first matrix layer consists of (i) 60 to 80% (w/w) nicotine and (ii) a methacrylate copolymer thickener,
the second matrix layer as-applied consists of (i) (meth)acrylate copolymer adhesive consisting entirely of crosslinkable acrylate copolymers having an acid value of from 20 to 100 mg KOH per gram of polymer, (ii) crosslinker, (iii) a neutralization reagent, (iv) hydroabsorbent, and (v) methacrylate copolymer thickener.
2. A method as claimed in claim 1 , wherein the flexural stiffness of the transdermal system to be applied to the skin is not more than 2 cN×cm 2 .
3. A method as claimed in claim 1 , wherein the matrix layers are free from supports and strengthening layers.
4. A method as claimed in claim 1 , wherein the method further comprises the transdermal system dispensing from about 0.7 to about 1.4 mg of nicotine per cm 2 of skin within 24 hours.
5. A method as claimed in claim 4 , wherein the method further comprises the transdermal system dispensing from about 1.0 to about 1.4 mg of nicotine per cm 2 of skin within 24 hours.
6. A method as claimed in claim 1 , wherein the method further comprises the transdermal system dispensing from about 0.7 to about 1.4 mg, of nicotine per cm 2 of skin within 16 hours.
7. A method as claimed in claim 6 , wherein the method further comprises the transdermal system dispensing from about 1.0 to about 1.4 mg of nicotine per cm 2 of skin within 16 hours.
8. A method as claimed in claim 1 , wherein the methacrylate copolymer is a butyl methacrylate-(2-dimethylaminoethyl methacrylate)-methyl methacrylate copolymer or a butyl methacrylate-methyl methacrylate copolymer.
9. A method for the manufacture of a transdermal therapeutic system with nicotine content, composed of a backing layer impermeable to nicotine, a first matrix layer containing nicotine immediately adjacent to the backing layer, a second matrix layer, and a peelable protective layer, where the matrix layers are composed of (meth)acrylate copolymers, and the total thickness of the backing layer and first and second matrix layers does not exceed 250 μm and the nicotine-content is at least 1.5 mg per cm 2 of application surface,
said method comprising applying the first matrix layer using printing technology to a portion of the second matrix layer, said second matrix layer forming an external margin around the first matrix layer,
wherein the second matrix layer comprises a pressure-sensitive-adhesive based on acrylate copolymers and the acrylate copolymer of the second matrix layer contains carboxy groups and is completely or partially neutralized by one or more basic additives and/or in a form crosslinked by aluminum ions or titanium ions, and the basic additive is an alkali metal hydroxide or a basic polymer and
the first matrix layer consists of 60 to 80% (w/w) nicotine and polymer derived from methacrylic acid or esters thereof.
10. A method as claimed in claim 9 , wherein the alkali metal hydroxide is potassium hydroxide and the basic polymer is butyl methacrylate-(2-dimethylaminoethyl methacrylate)-methyl methacrylate copolymer (1:2:1).
11. A method as claimed in claim 9 , wherein at least one strongly water-binding auxilary is present in the second matrix layer of the transdermal system.
12. A method as claimed in claim 11 , wherein the auxilary is a polymer containing carboxy groups or its pharmaceutically acceptable salt.
13. A method as claimed in claim 1 , wherein the (meth)acrylate copolymers of the matrix layers are processed in solvent-containing systems.
14. A method as claimed in claim 1 , wherein the transdermal therapeutic system has four layers.
15. A method according to claim 1 , wherein said system consists of
(i) a backing layer impermeable to nicotine, (ii) a first matrix layer immediately adjacent to the backing layer, (iii) a second matrix layer, and (iv) a peelable protective layer adjacent to the second matrix layer,
and said method consists of
coating the second matrix layer onto the peelable protective layer,
applying the first matrix layer to a portion of the second matrix layer,
mechanically laminating the backing layer onto the applied first matrix layer and the external margin formed by the second matrix layer,
the first matrix layer consisting of nicotine and a methacrylate copolymer thickener,
the second matrix layer as-applied consisting of (i) (meth)acrylate copolymer adhesive consisting entirely of crosslinkable acrylate copolymers having an acid value of from 20 to 100 mg KOH per gram of polymer, (ii) crosslinker, (iii) a neutralization reagent, (iv) hydroabsorbent, and (v) methacrylate copolymer thickener.