EP1711160A2

EP1711160A2 - Flat system for using in the oral cavity

Info

Publication number: EP1711160A2
Application number: EP05707164A
Authority: EP
Inventors: Stefan Bracht; Babett Gutsmuths
Original assignee: Schering AG
Current assignee: Bayer Pharma AG
Priority date: 2004-02-03
Filing date: 2005-02-03
Publication date: 2006-10-18
Also published as: KR20060123610A; AU2005210123A1; WO2005074882A3; CA2554892A1; NO20063915L; CN1913870A; BRPI0507389A; WO2005074882A2; JP2007520517A; US20070298084A1; DE102004017030A1

Abstract

The invention relates to a flat system for using in the oral cavity, and to a method for the production thereof. Said system consists of at least one upper water-soluble covering layer and at least one lower water-soluble covering layer. At least one intermediate layer is provided between the upper and lower covering layers, said intermediate layer having a smaller surface area than the covering layers and being recessed along the edge of the flat system.

Description

Flat system for use in the oral cavity (description) Technical field The invention relates to a flat system for use in the

Oral cavity and a process for its manufacture. This system consists of at least one upper and at least one lower water-soluble cover layer. At least one intermediate layer is provided between the upper and the lower cover layer, which has a smaller area than the cover layers and is cut out along the edge of the flat system. PRIOR ART Flat preparations for use in the oral cavity are known. These are typically water-soluble polymer films that quickly disintegrate in the mouth when dissolved in saliva. The polymer film may contain oral or dental care, deodorant, disinfectant or refreshing components which essentially develop their effect in the oral cavity or in the nasopharynx. Products from this area are e.g. B. Eclipse Flash from Wrigley or Listerine PocketPaks from Pfizer.

In addition to the cosmetic application, active pharmaceutical ingredients can also be contained in the flat preparations - such products are currently under development. For the prior art, reference is made, for example, to the patents DE 2432925, DE 19956486A1, DE 1 9652257A1, DE 1 96521 88 DE 1 0107659 and WO 03/01 1259 A1.

Advantageous for pharmaceutical products is the possibility of ingestion without water, the avoidance of swallowing, which is perceived by some people as unpleasant, as well as numerous possibilities for the active ingredient in the mouth or through the mouth through e.g. B. transmucosal uptake into the bloodstream to be effective.

Disadvantages with flat medicament forms according to the prior art are as follows: the water-soluble polymer films are produced from aqueous solution at temperatures of typically up to over 100 ° C. and relatively long drying times, since the removal of water because of its high heat capacity compared to organic ones Solvents is a very energy-intensive process. These process conditions may be unsuitable for volatile or thermally unstable active substances

- or these can easily chemically decompose in aqueous solution at high temperatures.

- The two-dimensional drug forms typically contain the active ingredient in a full-area distribution. If shapes other than rectangular or square are produced, waste is generated by the waste. - The loading with the active ingredient leads to an impairment of the film-forming property of the water-soluble polymers (e.g. increase in brittleness) with its increasing concentration, or the loading capacity of the films is reduced by this effect.

- For the production of the water-soluble films, very hydrophilic polymers are used, which naturally have a low solubility for lipophilic active substances, which are often found in pharmaceutical use, such as. B. Steroid hormones. This results in poor loading of the films with lipophilic active ingredients, which then only in the form of a crystal suspension or as a multi-phase system such. B. emulsion can occur. The water-soluble polymer films generally consist of highly functional polymers with a large number of hydroxyl or carboxyl functions on the polymer chain. These highly functional polymers are capable of numerous chemical interactions with active pharmaceutical ingredients, from which stability problems can easily arise.

- The water-soluble polymer films typically require a residual moisture content for processability, which ensures sufficient flexibility or prevents brittleness. Experience has shown, however, that the residual water content in turn has a negative effect on the chemical stability of active substances in medicinal products.

DESCRIPTION OF THE INVENTION The object of the invention is therefore to overcome these disadvantages of conventional flat pharmaceutical products for use in the oral cavity. According to the invention the object is achieved by a flat system for use in the oral cavity, consisting of at least one upper and at least one lower water-soluble cover layer, with between at least one intermediate layer is provided for the upper and lower cover layers. This intermediate layer has a smaller surface area than the cover layers in that the intermediate layer is recessed along the edge of the flat system.

According to the invention, the upper and lower cover layers can be connected to one another by sealing in the edge region of the flat system. The width of the sealed seam can be 0.3-3 mm, preferably 0.5-2 mm and particularly preferably 0.75-1.5 mm. In the planar system according to the invention, the total thickness of this planar system at its thickest point can be 50 to 500 μm, preferably 100 to 300 μm and particularly preferably 150 to 250 μm. According to the invention, the intermediate layer can be water-soluble and have a melting point between 30 and 120 ° C, preferably between 50 and 100 ° C and particularly preferably between 60 and 90 ° C.

The intermediate layer can also be water-insoluble. Advantageous embodiments of the planar system according to the invention consist of the solid preparation of the intermediate layer, which melts at temperatures between 30 and 45 ° C., preferably between 32 and 40 ° C. and particularly preferably between 35 and 38 ° C.

The intermediate layer can consist of a base material which is used for the production of rectal suppositories, preferably one or more hard fats (Adeps Solidus) according to the monograph of the European Pharmacopoeia. The intermediate layer can also be an oily solution, suspension or emulsion.

According to the invention, the intermediate layer within the fabric can have a segmentation in that the upper and lower cover layers are connected to one another in this area by sealing. The intermediate layer can also contain at least one active pharmaceutical ingredient in dissolved or undissolved form.

Furthermore, the solubility of the active pharmaceutical ingredient in the intermediate layer can be at least n times 10, preferably n times 10-100, where n represents the solubility of the outer layers. A process for the production of a flat system is claimed, wherein in a first process step an intermediate layer of a lipophilic pharmaceutical is applied to a water-soluble polymer layer Preparation applied in a thin layer and then covered with a second water-soluble polymer layer, after which in a further process step the upper and lower polymer layers are connected to one another in sections by heat sealing, the intermediate layer being displaced under the influence of mechanical pressure at the sealing points between the upper and lower polymer layers and and compartments which are completely enclosed by the sealed cover layers continue to form in the intermediate layer. In the process according to the invention, the residual moisture in the water-soluble polymer films can be set to a value which improves the sealability, preferably 1-10% and particularly preferably 2-5% (m / m) water content. Furthermore, in the process according to the invention, the residual moisture in the water-soluble polymer films can be reduced by a drying process after the production of the flat capsules.

In the process according to the invention, the sealability of the water-soluble polymer films can also be ensured by plasticizing additives from the group of hydrophilic liquids, preferably from the group of polyhydric alcohols with 3 to 6 carbon atoms (C ₃ -C ₆ ), particularly preferably glycerol, 1, 2-propylene glycol , 1, 3-propylene glycol, 1, 3-butanediol, hexylene glycol or dipropylene glycol.

The flat system according to the invention can contain one or two steroid hormones for hormone replacement therapy or for hormonal contraception. The steroid hormones can be levonorgestrel, gestodene, dienogest, de-soestrestr, 3-keto-desogestrel, norelgestromin, drospirenone, estradiol, ethyl tradiol, estradiol valerate, testosterone, testosterone undecanoate, testosterone enanthate, 1alpha-n-methyl ester, 7alpha-n-methyl ester fluorine-containing derivatives. In the planar system according to the invention, an active ingredient from the group of organic nitrates (used for the treatment of angina pectoris), in particular glycerol trinitrate, or an active ingredient from the group of antiemetics, in particular 5-HT ₃ receptor antagonists and particularly preferably from the group of Ondansetron, granistron, ramosetron, alosetron or their pharmaceutically acceptable salts.

The flat system can also contain nicotine base or a pharmaceutically acceptable salt thereof. Both with organic nitrates and with nicotine, there is a need to make the active ingredient available in the bloodstream as quickly as possible via the oral mucosa. Active substances for the treatment of old age diseases, in particular Morbus Alzheimer's, Parkinson's disease and dementia diseases, as well as active substances for the treatment of severe mental illnesses such as schizophrenia or psychoses can be contained in the flat system according to the invention. These therapeutic fields are characterized in part by the fact that there is a reduced ability or willingness to swallow, which is why the use of a pharmaceutical form via the oral cavity is advantageous. Surprisingly, the existing object can be achieved in that a flat structure with a multilayer structure is selected in which the function of water-soluble polymer film is carried out separately from the function of the active substance carrier in different layers, the active substance-containing layer as an intermediate layer with a smaller area than the total area of the system is carried out by leaving out the intermediate layer along the edge of the planar system. Furthermore, the water-soluble polymer films can surprisingly be processed so that they can be heat-sealed. This is surprisingly true even if there is a lipophilic oily or waxy intermediate layer between these layers prior to heat sealing.

The invention makes it possible to embed an intermediate layer in the manner of an extremely flattened capsule in an envelope made of hydrophilic water-soluble polymer films.

The intermediate layer can consist of a liquid, semi-solid or waxy solid preparation. When used in the oral cavity, the coating of water-soluble polymer films first dissolves. The intermediate layer then disintegrates either by melting or by dissolving in the saliva or by both processes simultaneously.

In the case of melting the intermediate layer, an embodiment is preferred in which the mass melts between 32 and 37 ° C. at the typical temperatures of the interior of the mouth. In this way, the intermediate layer is practically imperceptible to the sensor, the mouthfeel is significantly more pleasant than in the case of a permanent intermediate layer. Furthermore, the release of active substance from the lipophilic layer is facilitated or accelerated by its melting. When using waxy interlayers it should be un do not melt below 30 ° C to avoid melting during storage of the medicinal product.

For the production of the outer water-soluble covering layers are water-soluble polymer are suitable for the group of polyvinyl alcohols degree of hydrolysis of 75-99% (eg. B. Mowiol ^® types), polyvinylpyrrolidone, hydrophilic cellulose derivatives such as hydroxypropylcellulose, Hydroxymethylpropylcellulsoe or carboxymethyl cellulose, pullulan, or maltose, hydrophilic starch derivatives such as carboxymethyl starch, alginates or gelatin and other polymers known in the prior art.

The formulation or the processing of the intermediate layer is essentially determined by three requirements: 1. The intermediate layer should dissolve quickly in the mouth by melting or dissolving in saliva or a combination of both. 2. In the preferred case, the intermediate layer is coated directly onto a water-soluble polymer layer and, in terms of process engineering, should not require any solvents which can dissolve the polymer layer serving as the coating substrate. 3. The intermediate layer must be thermoplastically deformable in order to be able to shrink back between the cover layers during heat sealing.

A waxy, low-melting formulation is preferably suitable for the formulation of the lipophilic intermediate layer. For this, reference is made to the production of rectal suppositories (suppositories) or vaginal suppositories. A selection of low-melting base materials with a melting point that can be selected within wide limits is, for. B. from the group of Softisan ^® and Witepsol ^® hard fats possible. Suitable carriers are also described in the monograph "Hard Fat" (Adeps Solidus) of the European Pharmacopoeia. Alternatively, oily, viscous solutions can be used as an intermediate layer. Suitable carriers are pharmaceutically customary oils and lipophilic liquids, which should preferably be largely tasteless, e.g. saturated triglycerides (eg Miglyol 812), isopropyl myristate or isopropyl palmitate. Thickeners can be added to these oily solutions to increase the viscosity. For this purpose, polymers from the group of polyacrylates (eg Eudragit ^® E 100 or Plastoid ^® B), polyvinylpyrrolidone (Kollidon ^® 25, 30, 90 or VA 64), polyvinyl acetate (e.g. Kollidon ^® SR), polyethylene glycol or lithium pophilic cellulose derivatives (e.g. ethyl cellulose or cellulose acetate butyrate).

As a polymer component of the intermediate layer, z. B. polyvinyl pyrrolidone (PVP) or its copolymers z. B. Kollidon ^® 25, 30, 90 or VA 64, and polyethylene glycols (macrogols) with molecular weights greater than 2000 Da.

If necessary, the formulation of the intermediate layer can include, for example, additives from the groups of plasticizers, surfactants, solubilizers, penetration improvers, release agents, antioxidants, light and UV protection agents, pigments, dyes, taste corrections, organic or inorganic fillers, without any claim to completeness as well as fragrances are added. Solubilizers and penetration enhancers are particularly important:

On the one hand, the flat capsules according to the invention have only a small internal volume, as a result of which the loadability with active substances is restricted. Furthermore, it can be advantageous if the active ingredients contained are taken up entirely or predominantly in the mouth via the mucous membrane, instead of only after swallowing through the gastrointestinal tract.

The formulation of the intermediate layer should have the highest possible solvency for the intended active ingredient, for which purpose solubilizers can be used. The solubilizers must be selected in such a way that they do not jeopardize the integrity of the water-soluble cover layers by dissolving or dissolving or by greatly softening them.

Suitable solubilizers are e.g. B. fatty acid esters of saturated fatty acids with chain lengths of 6 to 18 carbon atoms with mono- to trihydric aliphatic alcohols with 2 to 4 carbon atoms (e.g. ethyl oleate, propylene glycol monolaurate, glycerol monooleate), furthermore fatty alcohol ethers of fatty alcohols with 6 to 18 carbon atoms with polyethylene glycol (e.g. BRIJ ^® products), fatty acid esters of fatty acids with 6 to 1 8 carbon atoms with polyethylene glycol (e.g. MYRJ ^® products), esters of fatty alcohols with 6 to 1 8 carbon atoms with carboxylic acids with 2 to 3 carbon atoms (e.g. lauryl lactate or Lauryl acetate), sorbitan fatty acid esters (e.g. SPAN ^® products), sorbitan polyethylene glycol ether fatty acid esters (e.g. TWEEN ^® products), citric acid esters (e.g. triethyl citrate or acetyltributyl citrate), Diethylene glycol monoethyl ether (Transcutol ^® ), propylene carbonate, Solketal, Glycofurol, triacetin, cyclodextrins.

The compositions of the intermediate layer and the outer layers are advantageously chosen such that the solubility of the active substance in the intermediate layer is significantly greater in the intermediate layer than in the outer layers. This reduces possible undesired chemical decomposition reactions of the active substance after immigration into the outer layers. To produce the two-dimensional systems according to the invention, a water-soluble polymer film is first produced by coating a solution on a web-shaped support material and then drying it. Alternatively, the film can also be produced by a solvent-free hot melt process. The weight per unit area of the polymer layer is 25-200 g / m ² , preferably 40-150 g / m ² and particularly preferably 60-100 g / m ² .

An intermediate layer is applied from the side of the water-soluble polymer to this preliminary product (polymer film on a backing material, for example paper with a repellent coating). This is preferably a medium-viscosity, lipophilic liquid or the melt of a lipophilic mass. The application of the lipophilic liquid or mass can, for. B. with the help of a slot die, a doctor blade or roller applicator or a knife caster.

The weight per unit area of this intermediate layer is 25-300 g / m ² , preferably 30-200 g / m ² and particularly preferably 40-150 g / m ² . The intermediate layer is preferably not coated up to the edge of the underlying polymer layer, but at least 0.5 to 5 cm of space remain at the edge in order to prevent the intermediate layer from escaping at the edge in the subsequent method steps. The exposed surface of the intermediate layer, after it has solidified again by cooling, is covered with a second water-soluble polymer layer, which as a rule has the same composition and method of manufacture as the first polymer layer lying at the bottom. However, the second water-soluble polymer layer is preferably first detached from its support material and laminated onto the intermediate layer as a single layer.

In a second process step, the composite of carrier material, first water-soluble polymer layer, lipophilic intermediate layer and second water-soluble polymer layer with a suitable sealing mask coming from the uppermost, open-lying polymer layer and thus the web-shaped carrier material furthest away from the side, a heat seal is carried out.

The intermediate layer between the water-soluble polymer films is optionally first melted and then displaced by mechanical pressure on the parts to be sealed until the two water-soluble polymer films form a permanent bond with one another at these points by heat sealing.

For the heat sealability it can be advantageous to maintain a residual moisture in the water-soluble polymer films or to adjust this by moistening. The sealability of the water-soluble polymer films can also be increased by plasticizing additives from the group of hydrophilic liquids, preferably by additives from the group of polyhydric alcohols with 3 to 6 carbon atoms (C ₃ -C ₆ ), particularly preferably glycerol, 1, 2-propylene glycol, 1, 3-propylene glycol, 1, 3-butanediol, hexylene glycol or dipropylene glycol. In cases in which residual moisture is required for the sealability, it may be necessary to dry the product after manufacture, or to set the residual moisture to a lower value than when sealing, in order to increase the chemical storage stability of the product. For the production of individually dosed forms, the upper and the lower polymer layer are sealed together along an intended contour line in such a way that a quantity of the lipophilic intermediate layer defined over the surface is completely enclosed in the manner of a single dose. In this process step, based on the active substance-containing intermediate layer, the individual doses are formed, which is why the sealing mask used should have corresponding dimensional accuracies of plus or minus 5% or better in order to be able to comply with the pharmaceutically required dosage accuracies.

With regard to the construction of the sealing masks, it is advantageous to round off the edges of the sealing contour in order not to exert unnecessarily high shear forces on the typically brittle water-soluble polymer films. Finally, the fabric is mechanically cut or punched along the sealed seams and divided into individual shapes or groups of individual shapes. The remaining web widths of the sealed edge areas of the flat structures should be kept as small as possible, since in these areas the water-soluble polymer films of the upper and lower cover layers together form a particularly thick zone, which allows the slowest dissolution rate in the mouth and a negative effect on the mouthfeel to be expected , The width of the sealed seam should be 0.3 to 3 mm, preferably 0.5 to 2 mm and particularly preferably 0.75 to 1.5 mm. Description of the pictures:

FIG. A1 schematically shows a flat system in cross section: an upper cover layer (1), together with a lower cover layer (2), encloses an inner intermediate layer (3). In the case of FIG. A1, the two outer layers have a flat cavity, while in FIG. A2 the cavity for receiving the intermediate layer is only present in one of the two cover layers. The cover layers (1) and (2) can be of identical or different nature. In Figure A3 a flat system with two separate chambers (3 and 4) is shown, which is formed with the help of a further cover layer (5).

FIG. B shows a flat intermediate product after the heat-sealing step has taken place, in which case there may be several sections of the intermediate layer containing the active substance that are separate from one another, both longitudinally and transversely, which are converted into the end products in further process steps by cutting or punching , Figures C1 to C5 show different embodiments of the fabrics according to the invention in a top view. They essentially serve to illustrate the possible embodiments. While the structures C2 and C3 are of greater visual acceptance by the consumers, the structures C1, C4 and C5 have a higher degree of utilization of the flat intermediate product with less waste production, although this is an active substance-free waste. Compared to FIG. C4, FIG. C5 illustrates the possibility that the contour line of the inner active substance-containing intermediate layer does not follow the outer contour line of the fabric got to.

FIG. D shows an example of a flat structure with several active ingredient-containing sections (3). This product is a multi-dose structure that can be divided into different single doses.

Figures E 1 to E4 illustrate a method step of heat sealing according to the invention. The laminate consisting of an upper (1) and a lower (2) cover layer with an inner intermediate layer (3) on a web-shaped carrier material (6) is pressed against a counterpressure surface (8) belonging to the sealing station by an embossing heat sealing tool (7). pressed, whereby either only the sealing tool or else the sealing tool and counter-pressure plate are heated.

This method step can also be carried out with a counterpressure plate which has a flat cavity, as a result of which an approximately symmetrical shape of the flat system according to the invention is produced in cross section. The result of such a sealing is shown schematically in FIG. E3. In FIG. E4, curves are provided at the points on the sealing mask (7) marked with arrows, which lead to a reduction in the mechanical deformation stress on the cover layer (1) and thus reduce the risk of cracks or leaks at the sealing seam. This technique can also be applied analogously to the bilateral shaping according to FIG. E3.

Figures E1 to E4 illustrate the relevant method step on a flat bed sealing punch for a clocked mode of operation in which the laminate web is stopped during the processing step. Analogously, this process step can also be carried out on rotary systems with appropriately contoured sealing or embossing rollers and with the laminate web running continuously. For the primary packaging of the systems according to the invention, reference is made to patent steps DE 19800682, DE 10008165, DE 10144287, DE 10102818, DE 1 01 59746A1 and DE 1 01431 20A1 and the prior art cited therein. Exemplary embodiments Example 1: Three-layer flat capsule with a wax-like semi-solid intermediate layer

Intermediate layer: semi-solid

Materials: Eclipse ™ Peppermint Papers (3x2cm) (Wrigley) Softisan 1 00 (hard fat) (Sasol) Temperature-controlled water bath Beaker, disposable Pasteur pipette sealing tongs

Execution: a lipophilic intermediate layer

Softisan 100 is heated until it melts on the water bath. Using a Pasteur pipette, Softisan 100 is applied evenly to the entire EclipseTM Peppermint leaflet (3x2crn). After solidification of the hard fat occurs, another EclipseTM Peppermint leaflet (3x2cm) is applied precisely to the lipophilic layer. The three-layer intermediate product is then sealed from all four sides with the aid of a sealing tongs heated to approx. 1 60 ° C for approx. 5 seconds.

Example 2: Five-layer flat capsule with 2 semi-solid intermediate layers

Softisan 1 00 is heated to a clear melt on a water bath. Using a Pasteur pipette, Softisan 100 is applied evenly to the entire Eclipse ™ Peppermint leaflet (3x2cm). After the hard fat solidifies, another EclipseTM Peppermint leaflet (3x2cm) is applied precisely to the lipophilic layer. A second layer of hard fat is applied, which in turn is covered with an Eclipse ™ Peppermint leaflet (3x2cm) to ensure a perfect fit. The five-layer intermediate product is then sealed from all four sides with the aid of sealing tongs heated to approx. 1 60 ° C. for approx. 8 seconds. Example 3: Three-layer flat capsule with an oily intermediate layer Materials: Eclipse ™ Peppermint papers (3x2cm) (Wrigley) Viscose paraffin disposable Pasteur pipette sealing pliers Version:

Viscose paraffin is applied evenly to the entire EclipseTM Peppermint leaflet (3x2cm) using a Pasteur pipette. Another EclipseTM Peppermint leaflet (3x2cm) is applied precisely to the lipophilic layer. The three-layer intermediate product is then sealed from all four sides with the aid of sealing tongs heated to approx. 160 ° C for approx. 5 seconds. Determinations and calculations used in Examples 1-3: To determine the basis weight (FG), the multilayer products produced are weighed individually and the respective areas are determined. The weight of 10 Eclipse ™ Peppermint papers is determined and the mean is calculated. The dimensions are determined accordingly and the area is calculated. The conversion of the units is taken into account in the calculation formula.

Papers: FG _b = - ^ * 10 ^b A FG _b : basis weight (g / m ² ) m _b : mass (mean) (mg) A: area (cm ² )

FlatCaps: FG _fc = ^ ° - * 10 FG _fc : basis weight (g / m ² ) m _fc : mass (mg)

Lipophilic intermediate layer: FG = FG _fc - FG _b

Values between 45 and 55 g / m ^{2 were} determined for the basis weight of the Eclipse ™ Peppermint papers in the examples.

The weight per unit area of the softisan layer in example 1 was 132 g / m ² . The weight per unit area of the oily layer in Example 3 was 80 g / m ² .

Claims

Expectations

1. Flat system for use in the oral cavity, consisting of at least one upper and at least one lower water-soluble

Cover layer, at least one intermediate layer being provided between the upper and the lower cover layer, characterized in that the intermediate layer has a smaller area than the cover layers in that the intermediate layer is recessed along the edge of the flat system.

2. Flat system according to claim 1, characterized in that the upper and the lower cover layer in the edge region of the flat system are connected to one another by sealing. 3. Flat system according to one or more of the preceding claims, characterized in that the width of the sealing seam 0,

3 - 3 mm, preferably 0.5 - 2 mm.

4. Flat system according to one or more of the preceding claims, characterized in that the total thickness of the flat system at its thickest point is 50 to 500 μm, preferably 100 to 300 μm.

5. Flat system according to one or more of the preceding claims, characterized in that the intermediate layer is water-soluble and has a melting point between 30 and 120 ° C, preferably between 50 and 100 ° C.

6. Flat system according to one or more of claims 1 to 4, characterized in that the intermediate layer is water-insoluble.

7. Flat system according to claim 6, characterized in that the intermediate layer is a solid preparation which melts at temperatures between 30 and 45 ° Celsius, preferably between 32 and 40 ° C.

8. Flat system according to claim 7, characterized in that the intermediate layer consists of a base material which is used for the production of rectal suppositories, preferably one or more hard fats (adeps solidus) according to the monograph of the European Pharmacopoeia.

9. Flat system according to claim 6, characterized in that the intermediate layer is an oily solution, suspension or emulsion.

10. Flat system according to one or more of the preceding claims, characterized in that the intermediate layer has a segmentation within the fabric by the upper and lower cover layers are connected to one another in this area by sealing.

11. Flat system according to one or more of the preceding claims, characterized in that the intermediate layer contains at least one active pharmaceutical ingredient in dissolved or undissolved form.

12. Flat system according to claim 1 1, characterized in that the solubility of the active pharmaceutical ingredient in the intermediate layer is at least n times 10, preferably n times 10- 100, where n represents the solubility of the outer layers.

13. A method for producing a flat system according to one or more of the preceding claims, characterized in that

an intermediate layer of a lipophilic pharmaceutical preparation is applied in a thin layer to a water-soluble polymer layer,

is then covered with a second water-soluble polymer layer,

- The upper and lower polymer layers are connected to one another in sections by heat sealing, the intermediate layer being displaced under the influence of mechanical pressure at the sealing points between the upper and lower polymer layers, and compartments which are completely enclosed by the sealed cover layers continue to form in the intermediate layer.

14. The method according to claim 13, characterized in that the residual moisture in the water-soluble polymer films is set to a value which improves the sealability, preferably 1-10% (m / m) water content.

15. The method according to claim 14, characterized in that the residual moisture in the water-soluble polymer films is reduced after the production of the flat capsules by a drying process.

16. The method according to claim one or more of claims 13 to 15, characterized in that the sealability of the water-soluble polymer films is ensured by plasticizing additives from the group of hydrophilic liquids, preferably from the group of polyhydric alcohols with 3 to 6 carbon atoms (C ₃ - C ₆ ). particularly preferably glycerol, 1, 2-propylene glycol, 1, 3-propylene glycol, 1, 3-butanediol, hexylene glycol or dipropylene glycol.