US5543155A
Expired / Lapsed
US
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Diffusion-osmotic controlled drug-release pharmaceutical composition and process for preparing same
Assignee: Egis Gyógyszergyár Zrt
•
Filing: 1994-12-05
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Granted: 1996-08-06
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Expires: 2014-12-05
Abstract
Abstract The invention relates to a novel diffusion-osmotic controlled drug-release pharmaceutical composition containing a one-layer tablet core including a polymeric film-coat, a therapeutically active agent and a hydrophilic polymer; if desired, a two-layer tablet core including active agent and hydrophilic polymer in the first layer thereof and a hydrophilic polymer in the second layer thereof; at least one bore on the part of film-coat in contact with the core or core layer containing the active agent; and, if desired, containing one or more bore(s) in the part thereof in contact with the second layer containing the hydrophilic polymer, which comprises an ammonium methacrylate copolymer as coating material and hydroxypropyl-methylcellulose as hydrophilic polymer. The composition according to the invention is useful for preparing controlled drug-release tablets containing as active agents e.g. beta -adrenergic inhibitors (e.g. propranolol) calcium-antagonists (e.g. nifedipine), angiotensin convertase enzyme (ACE) inhibitors (e.g. captopril); prazosin; or nitroglycerol, all used in heart and circulation diseases; vasodilatory active agents (e.g. pentoxyfylline), nonsteroidal antiinflammatory agents (e.g. naproxene), analgetic drugs (e.g. morphine) and drugs acting on the central nervous system (e.g. amitriptyline, buspiron). The invention furthermore relates to a process for the preparation of the above compositions.
Inventors
- 👤 Pal Fekete
- 👤 Maria Kiraly nee Ignacz
- 👤 Gabor Sipos
- 👤 Zsuzsanna Jambor nee Hoffmann
- 👤 Gyorgy Ujfalussy
- 👤 Magdolna Gora nee Hernyes
- 👤 Imre Klebovich
- 👤 Sandor Drabant
- 👤 Attila Mandi
- 👤 Gizella Kiss nee Szabo
- 👤 Erzsebet Barczay
- 👤 Maria Krisztian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:31
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/0002; A61K9/0004; A61K47/00; A61K47/30; A61K47/32; A61K47/36; A61K47/38
Claims Analysis
Total Claims: 59
Claim 1
Independent Claim
82 words
A diffusion-osmotic controlled drug-release pharmaceutical composition comprising a tablet core containing a therapeutically active agent and a hydrophilic polymer, wherein said tablet core is coated with a polymeric film-coat, and said film-coat contains at least one bore in said film-coat in contact with said tablet core, said film-coat comprising an ammonium methacrylate copolymer and said hydrophilic polymer comprising hydroxypropyl methylcellulose, said film-coat being present in an amount of 3 to 25 mg/cm 2 in relation to the surface of said tablet core.
Claim 2
Dependent Claim
82 words
A diffusion-osmotic controlled drug-release pharmaceutical composition comprising a tablet core containing a therapeutically active agent and a hydrophilic polymer, wherein said tablet core is coated with a polymeric film-coat, and said film-coat contains at least one bore in said film-coat in contact with said tablet core, said film-coat comprising an ammonium methacrylate copolymer and said hydrophilic polymer comprising hydroxypropyl methylcellulose, said film-coat being present in an amount of 3 to 25 mg/cm 2 in relation to the surface of said tablet core.
Claim 3
Dependent Claim
30 words
The composition according to claim 1, wherein said hydroxypropyl methylcellulose is present in an amount of 5 to 30% by weight in relation to the weight of said tablet core.
Claim 4
Dependent Claim
44 words
The composition according to claim 1, said tablet core further comprising 0 to 90% by weight of filling material, 0 to 5% by weight of binding material, and 0 to 5% by weight of lubricant in relation to the weight of said tablet core.
Claim 5
Dependent Claim
21 words
The composition according to claim 3, wherein said filling material is cellulose, microcrystalline cellulose, starch, lactose, mannitol, or secondary calcium phosphate.
Claim 6
Dependent Claim
23 words
The composition according to claim 3, wherein said binding material is hydroxypropyl-cellulose, methylcellulose, hydroxypropylmethylcellulose, polyvinylpyrrolidone, ethylcellulose, gelatine, water-soluble starch, polyvinylalcohol, polyoxyethyleneglycol, or polyvinylbutyral.
Claim 7
Dependent Claim
22 words
The composition according to claim 3, wherein said lubricant is magnesium stearate, talc, stearic acid, hydrogenated castor oil, or colloidal silicon dioxide.
Claim 8
Dependent Claim
43 words
The composition according to claim 1, wherein said ammonium methacrylate copolymer has a relative molecular weight of 100,000 to 200,000 and contains 1 molar part of ethyl acrylate, 2 molar parts of methyl methacrylate and 0.1 to 0.2 molar part of (trimethylammonio)-ethyl methacrylate.
Claim 9
Dependent Claim
81 words
The composition according to claim 1, wherein said ammonium methacrylate copolymer comprises a 1:10 to 10:1 ratio of an ammonium methacrylate copolymer with a relative molecular weight of 150,000 containing 1 molar part of ethyl acrylate, 2 molar parts of methyl methacrylate and 0.1 molar part of (trimethylammonio)-ethyl methacrylate to an ammonium methacrylate copolymer with a relative molecular weight of 150,000 containing 2 molar parts of methyl methacrylate, 1 molar part of ethyl methacrylate and 0.2 molar part of (trimethylammonio)-ethyl methacrylate.
Claim 10
Dependent Claim
42 words
The composition according to claim 1, wherein said hydroxypropyl methylcellulose contains 20 to 30% by weight of methoxy groups and 5 to 12% by weight of hydroxypropyl groups and has a viscosity of 3 to 100,000 cP in a 2% aqueous solution.
Claim 11
Dependent Claim
126 words
A diffusion-osmotic controlled drug-release pharmaceutical composition comprising a tablet core containing a therapeutically active agent, 5 to 30% by weight of hydroxypropyl methylcellulose, 0 to 90% by weight of filling material, at most 5% by weight of binding material and at most 5% by weight of lubricant in relation to the total weight of said tablet core; wherein said tablet core is coated with a polymeric film-coat of an ammonium methacrylate copolymer, and said film-coat contains at least one bore in said film-coat in contact with said tablet core, said film-coat being present in amount of 3 to 25 mg/cm 2 in relation to the surface of said tablet core, and said film-coat contains one or more bores of 0.1 to 1.0 mm 2 in cross-section.
Claim 12
Dependent Claim
126 words
A diffusion-osmotic controlled drug-release pharmaceutical composition comprising a tablet core containing a therapeutically active agent, 5 to 30% by weight of hydroxypropyl methylcellulose, 0 to 90% by weight of filling material, at most 5% by weight of binding material and at most 5% by weight of lubricant in relation to the total weight of said tablet core; wherein said tablet core is coated with a polymeric film-coat of an ammonium methacrylate copolymer, and said film-coat contains at least one bore in said film-coat in contact with said tablet core, said film-coat being present in amount of 3 to 25 mg/cm 2 in relation to the surface of said tablet core, and said film-coat contains one or more bores of 0.1 to 1.0 mm 2 in cross-section.
Claim 13
Dependent Claim
123 words
A diffusion-osmotic controlled drug-release pharmaceutical composition comprising a two-layer tablet core, wherein the first layer of said two-layer tablet core contains a therapeutically active agent and a hydrophilic polymer, and the second layer of said two-layer tablet core contains a hydrophilic polymer, said two-layer tablet core being covered with a polymeric film-coat, the part of said film-coat in contact with said first layer contains at least one bore and the part of said film-coat in contact with said second layer optionally contains at least one bore, said film-coat comprising an ammonium methacrylate copolymer and said hydrophilic polymer comprising hydroxypropyl methylcellulose, said film-coat being present in an amount of 3 to 25 mg/cm 2 in relation to the surface of said two-layer tablet core.
Claim 14
Dependent Claim
123 words
A diffusion-osmotic controlled drug-release pharmaceutical composition comprising a two-layer tablet core, wherein the first layer of said two-layer tablet core contains a therapeutically active agent and a hydrophilic polymer, and the second layer of said two-layer tablet core contains a hydrophilic polymer, said two-layer tablet core being covered with a polymeric film-coat, the part of said film-coat in contact with said first layer contains at least one bore and the part of said film-coat in contact with said second layer optionally contains at least one bore, said film-coat comprising an ammonium methacrylate copolymer and said hydrophilic polymer comprising hydroxypropyl methylcellulose, said film-coat being present in an amount of 3 to 25 mg/cm 2 in relation to the surface of said two-layer tablet core.
Claim 15
Dependent Claim
34 words
The composition according to claim 11, wherein said hydroxypropyl methylcellulose in said first layer is present in an amount of 5 to 30% by weight in relation to the weight of said first layer.
Claim 16
Dependent Claim
34 words
The composition according to claim 11, wherein said hydroxypropyl methylcellulose in said second layer is present in an amount of 30 to 100% by weight in relation to the weight of said second layer.
Claim 17
Dependent Claim
45 words
The composition according to claim 11, wherein said first layer further comprises 0 to 90% by weight of filling material, 0 to 5% by weight of binding material, and 0 to 5% by weight of lubricant in relation to the weight of said first layer.
Claim 18
Dependent Claim
44 words
The composition according to claim 11, said second layer further comprising 0 to 70% by weight of filling material, 0 to 5% by weight of binding material, and 0 to 5% by weight of lubricant in relation to the weight of said second layer.
Claim 19
Dependent Claim
21 words
The composition according to claim 14, wherein said filling material is cellulose, microcrystalline cellulose, starch, lactose, mannitol, or secondary calcium phosphate.
Claim 20
Dependent Claim
23 words
The composition according to claim 14, wherein said binding material is hydroxypropyl-cellulose, methylcellulose, hydroxypropylmethylcellulose, polyvinylpyrrolidone, ethylcellulose, gelatine, water-soluble starch, polyvinylalcohol, polyoxyethyleneglycol, or polyvinylbutyral.
Claim 21
Dependent Claim
22 words
The composition according to claim 14, wherein said lubricant is magnesium stearate, talc, stearic acid, hydrogenated castor oil, or colloidal silicon dioxide.
Claim 22
Dependent Claim
21 words
The composition according to claim 15, wherein said filling material is cellulose, microcrystalline cellulose, starch, lactose, mannitol, or secondary calcium phosphate.
Claim 23
Dependent Claim
23 words
The composition according to claim 15, wherein said binding material is hydroxypropyl-cellulose, methylcellulose, hydroxypropylmethylcellulose, polyvinylpyrrolidone, ethylcellulose, gelatine, water-soluble starch, polyvinylalcohol, polyoxyethyleneglycol, or polyvinylbutyral.
Claim 24
Dependent Claim
22 words
The composition according to claim 15, wherein said lubricant is magnesium stearate, talc, stearic acid, hydrogenated castor oil, or colloidal silicon dioxide.
Claim 25
Dependent Claim
43 words
The composition according to claim 11, wherein said ammonium methacrylate copolymer has a relative molecular weight of 100,000 to 200,000 and contains 1 molar part of ethyl acrylate, 2 molar parts of methyl methacrylate and 0.1 to 0.2 molar part of (trimethylammonio)-ethyl methacrylate.
Claim 26
Dependent Claim
81 words
The composition according to claim 11, wherein said ammonium methacrylate copolymer comprises a 1:10 to 10:1 ratio of an ammonium methacrylate copolymer with a relative molecular weight of 150,000 containing 1 molar part of ethyl acrylate, 2 molar parts of methyl methacrylate and 0.1 molar part of (trimethylammonio)-ethyl methacrylate to an ammonium methacrylate copolymer with a relative molecular weight of 150,000 containing 2 molar parts of methyl methacrylate, 1 molar part of ethyl methacrylate and 0.2 molar part of (trimethylammonio)-ethyl methacrylate.
Claim 27
Dependent Claim
42 words
The composition according to claim 11, wherein said hydroxypropyl methylcellulose contains 20 to 30% by weight of methoxy groups and 5 to 12% by weight of hydroxypropyl groups and has a viscosity of 3 to 100,000 cP in a 2% aqueous solution.
Claim 28
Dependent Claim
26 words
The composition according to claim 11, wherein said hydroxypropyl methylcellulose in said second layer has a viscosity higher than 1000 cP in a 2% aqueous solution.
Claim 29
Dependent Claim
201 words
A diffusion-osmotic controlled drug-release pharmaceutical composition comprising a two-layer tablet core, wherein the first layer of said two-layer tablet core contains a therapeutically active agent, 5 to 30% by weight of hydroxypropyl methylcellulose, 0 to 90% by weight of filling material, at most 5% by weight of binding material and at most 5% by weight of lubricant in relation to the total weight of said first layer; and the second layer of said two-layer tablet core contains 30 to 100% by weight of hydroxypropyl methylcellulose having a viscosity higher than 1000 cP in 2% aqueous solution, 0 to 70% by weight of filling material, 0 to 5% by weight of binding material and 0 to 5% by weight of lubricant in relation to the total weight of said second layer; said two-layer tablet core being covered with a polymeric film-coat containing an ammonium methacrylate copolymer, the part of said film-coat in contact with said first layer contains at least one bore and the part of said film-coat in contact with said second layer optionally contains at least one bore, said film-coat being present in amount of 3 to 25 mg/cm 2 in relation to the surface of said two-layer tablet core.
Claim 30
Dependent Claim
201 words
A diffusion-osmotic controlled drug-release pharmaceutical composition comprising a two-layer tablet core, wherein the first layer of said two-layer tablet core contains a therapeutically active agent, 5 to 30% by weight of hydroxypropyl methylcellulose, 0 to 90% by weight of filling material, at most 5% by weight of binding material and at most 5% by weight of lubricant in relation to the total weight of said first layer; and the second layer of said two-layer tablet core contains 30 to 100% by weight of hydroxypropyl methylcellulose having a viscosity higher than 1000 cP in 2% aqueous solution, 0 to 70% by weight of filling material, 0 to 5% by weight of binding material and 0 to 5% by weight of lubricant in relation to the total weight of said second layer; said two-layer tablet core being covered with a polymeric film-coat containing an ammonium methacrylate copolymer, the part of said film-coat in contact with said first layer contains at least one bore and the part of said film-coat in contact with said second layer optionally contains at least one bore, said film-coat being present in amount of 3 to 25 mg/cm 2 in relation to the surface of said two-layer tablet core.
Claim 31
Dependent Claim
89 words
A process for the preparation of a diffusion-osmotic controlled drug-release pharmaceutical composition comprising a tablet core containing a therapeutically active agent and a hydrophilic polymer, and said tablet core is coated with a polymeric film-coat, wherein said film-coat contains at least one bore in said film-coat in contact with said tablet core; said process comprising using hydroxypropyl methylcellulose as said hydrophilic polymer and an ammonium methacrylate copolymer as said coating material in an amount of 3 to 25 mg/cm 2 in relation to the surface of said tablet core.
Claim 32
Dependent Claim
89 words
A process for the preparation of a diffusion-osmotic controlled drug-release pharmaceutical composition comprising a tablet core containing a therapeutically active agent and a hydrophilic polymer, and said tablet core is coated with a polymeric film-coat, wherein said film-coat contains at least one bore in said film-coat in contact with said tablet core; said process comprising using hydroxypropyl methylcellulose as said hydrophilic polymer and an ammonium methacrylate copolymer as said coating material in an amount of 3 to 25 mg/cm 2 in relation to the surface of said tablet core.
Claim 33
Dependent Claim
26 words
The process according to claim 27, comprising using 5 to 30% by weight of said hydroxypropyl methylcellulose in relation to the weight of said tablet core.
Claim 34
Dependent Claim
45 words
The process according to claim 27, comprising using in said tablet core 0 to 90% by weight of filling material, 0 to 5% by weight of binding material, and 0 to 5% by weight of lubricant in relation to the weight of said tablet core.
Claim 35
Dependent Claim
21 words
The process according to claim 29, wherein said filling material is cellulose, microcrystalline cellulose, starch, lactose, mannitol, or secondary calcium phosphate.
Claim 36
Dependent Claim
23 words
The process according to claim 29, wherein said binding material is hydroxypropyl-cellulose, methylcellulose, hydroxypropylmethylcellulose, polyvinylpyrrolidone, ethylcellulose, gelatine, water-soluble starch, polyvinylalcohol, polyoxyethyleneglycol, or polyvinylbutyral.
Claim 37
Dependent Claim
22 words
The process according to claim 29, wherein said lubricant is magnesium stearate, talc, stearic acid, hydrogenated castor oil, or colloidal silicon dioxide.
Claim 38
Dependent Claim
43 words
The process according to claim 27, wherein said ammonium methacrylate copolymer has a relative molecular weight of 100,000 to 200,000 and contains 1 molar part of ethyl acrylate, 2 molar parts of methyl methacrylate and 0.1 to 0.2 molar part of (trimethylammonio)-ethyl methacrylate.
Claim 39
Dependent Claim
81 words
The process according to claim 27, wherein said ammonium methacrylate copolymer comprises a 1:10 to 10:1 ratio of an ammonium methacrylate copolymer with a relative molecular weight of 150,000 containing 1 molar part of ethyl acrylate, 2 molar parts of methyl methacrylate and 0.1 molar part of (trimethylammonio)-ethyl methacrylate to an ammonium methacrylate copolymer with a relative molecular weight of 150,000 containing 2 molar parts of methyl methacrylate, 1 molar part of ethyl methacrylate and 0.2 molar part of (trimethylammonio)-ethyl methacrylate.
Claim 40
Dependent Claim
42 words
The process according to claim 27, wherein said hydroxypropyl methylcellulose contains 20 to 30% by weight of methoxy groups and 5 to 12% by weight of hydroxypropyl groups and has a viscosity of 3 to 100,000 cP in a 2% aqueous solution.
Claim 41
Dependent Claim
178 words
A process for the preparation of a diffusion-osmotic controlled drug-release pharmaceutical composition comprising a tablet core containing a therapeutically active agent and hydroxypropyl methylcellulose, wherein said tablet core is coated with a polymeric film-coat of an ammonium methacrylate copolymer, and said film-coat contains at least one bore in said film-coat in contact with said tablet core; said process comprising mixing a therapeutically active agent with 5 to 30% by weight of hydroxypropyl methylcellulose and 0 to 90% by weight of filling material in relation to the total weight of said tablet core to form a mixture; mixing at most 5% by weight of lubricant with said mixture directly or after granulating with at most 5% by weight of binding material; preparing said tablet core by compression; coating said tablet core with an ammonium methacrylate copolymer in an amount of 3 to 25 mg/cm 2 in relation to the surface of said tablet core to form a film-coat on said tablet core; and establishing at least one bore of 0.01 to 1.0 mm 2 in cross-section on said film-coat.
Claim 42
Dependent Claim
178 words
A process for the preparation of a diffusion-osmotic controlled drug-release pharmaceutical composition comprising a tablet core containing a therapeutically active agent and hydroxypropyl methylcellulose, wherein said tablet core is coated with a polymeric film-coat of an ammonium methacrylate copolymer, and said film-coat contains at least one bore in said film-coat in contact with said tablet core; said process comprising mixing a therapeutically active agent with 5 to 30% by weight of hydroxypropyl methylcellulose and 0 to 90% by weight of filling material in relation to the total weight of said tablet core to form a mixture; mixing at most 5% by weight of lubricant with said mixture directly or after granulating with at most 5% by weight of binding material; preparing said tablet core by compression; coating said tablet core with an ammonium methacrylate copolymer in an amount of 3 to 25 mg/cm 2 in relation to the surface of said tablet core to form a film-coat on said tablet core; and establishing at least one bore of 0.01 to 1.0 mm 2 in cross-section on said film-coat.
Claim 43
Dependent Claim
25 words
The process according to claim 36, wherein said ammonium methacrylate copolymer is in an aqueous dispersion or solution with ethanol, isopropanol, acetone or mixtures thereof.
Claim 44
Dependent Claim
136 words
A process for the preparation of a diffusion-osmotic controlled drug-release pharmaceutical composition comprising a two-layer tablet core, wherein the first layer of said two-layer tablet core contains a therapeutically active agent and a hydrophilic polymer, wherein the second layer of said two-layer tablet core contains a hydrophilic polymer, wherein said two-layer tablet core is covered with a polymeric film-coat of an ammonium methacrylate copolymer, the part of said film-coat in contact with said first layer contains at least one bore and the part of said film-coat in contact with said second layer optionally contains at least one bore; said process comprising using hydroxypropyl methylcellulose as said hydrophilic polymer and an ammonium methacrylate copolymer as said coating material in an amount of 3 to 25 mg/cm 2 in relation to the surface of said two-layer tablet core.
Claim 45
Dependent Claim
136 words
A process for the preparation of a diffusion-osmotic controlled drug-release pharmaceutical composition comprising a two-layer tablet core, wherein the first layer of said two-layer tablet core contains a therapeutically active agent and a hydrophilic polymer, wherein the second layer of said two-layer tablet core contains a hydrophilic polymer, wherein said two-layer tablet core is covered with a polymeric film-coat of an ammonium methacrylate copolymer, the part of said film-coat in contact with said first layer contains at least one bore and the part of said film-coat in contact with said second layer optionally contains at least one bore; said process comprising using hydroxypropyl methylcellulose as said hydrophilic polymer and an ammonium methacrylate copolymer as said coating material in an amount of 3 to 25 mg/cm 2 in relation to the surface of said two-layer tablet core.
Claim 46
Dependent Claim
30 words
The process according to claim 38, comprising using in said first layer 5 to 30% by weight of said hydroxypropyl methylcellulose in relation to the weight of said first layer.
Claim 47
Dependent Claim
30 words
The process according to claim 38, comprising using in said second layer 30 to 100% by weight of said hydroxypropyl methylcellulose in relation to the weight of said second layer.
Claim 48
Dependent Claim
45 words
The process according to claim 38, comprising using in said first layer 0 to 90% by weight of filling material, 0 to 5% by weight of binding material, and 0 to 5% by weight of lubricant in relation to the weight of said first layer.
Claim 49
Dependent Claim
45 words
The process according to claim 38, comprising using in said second layer 0 to 70% by weight of filling material, 0 to 5% by weight of binding material, and 0 to 5% by weight of lubricant in relation to the weight of said second layer.
Claim 50
Dependent Claim
21 words
The process according to claim 41, wherein said filling material is cellulose, microcrystalline cellulose, starch, lactose, mannitol, or secondary calcium phosphate.
Claim 51
Dependent Claim
23 words
The process according to claim 41, wherein said binding material is hydroxypropyl-cellulose, methylcellulose, hydroxypropylmethylcellulose, polyvinylpyrrolidone, ethylcellulose, gelatine, water-soluble starch, polyvinylalcohol, polyoxyethyleneglycol, or polyvinylbutyral.
Claim 52
Dependent Claim
22 words
The process according to claim 41, wherein said lubricant is magnesium stearate, talc, stearic acid, hydrogenated castor oil, or colloidal silicon dioxide.
Claim 53
Dependent Claim
43 words
The process according to claim 38, wherein said ammonium methacrylate copolymer has a relative molecular weight of 100,000 to 200,000 and contains 1 molar part of ethyl acrylate, 2 molar parts of methyl methacrylate and 0.1 to 0.2 molar part of (trimethylammonio)-ethyl methacrylate.
Claim 54
Dependent Claim
81 words
The process according to claim 38, wherein said ammonium methacrylate copolymer comprises a 1:10 to 10:1 ratio of an ammonium methacrylate copolymer with a relative molecular weight of 150,000 containing 1 molar part of ethyl acrylate, 2 molar parts of methyl methacrylate and 0.1 molar part of (trimethylammonio)-ethyl methacrylate to an ammonium methacrylate copolymer with a relative molecular weight of 150,000 containing 2 molar parts of methyl methacrylate, 1 molar part of ethyl methacrylate and 0.2 molar part of (trimethylammonio)-ethyl methacrylate.
Claim 55
Dependent Claim
42 words
The process according to claim 38, wherein said hydroxypropyl methylcellulose contains 20 to 30% by weight of methoxy groups and 5 to 12% by weight of hydroxypropyl groups and has a viscosity of 3 to 100,000 cP in a 2% aqueous solution.
Claim 56
Dependent Claim
26 words
The process according to claim 38, wherein said hydroxypropyl methylcellulose in said second layer has a viscosity higher than 1000 cP in a 2% aqueous solution.
Claim 57
Dependent Claim
320 words
A process for the preparation of a diffusion-osmotic controlled drug-release pharmaceutical composition comprising a two-layer tablet core, wherein the first layer of said two-layer tablet core contains a therapeutically active agent and hydroxypropyl methylcellulose, wherein the second layer of said two-layer tablet core contains hydroxypropyl methylcellulose, wherein said two-layer tablet core is covered with a polymeric film-coat of an ammonium methacrylate copolymer, the part of said film-coat in contact with said first layer contains at least one bore and the part of said film-coat in contact with said second layer optionally contains at least one bore; said process comprising mixing a therapeutically active agent with 5 to 30% by weight of hydroxypropyl methylcellulose and 0 to 90% by weight of filling material in relation to the total weight of said first layer to form a mixture; mixing at most 5% by weight of lubricant with said mixture directly or after granulating with at most 5% by weight of binding material; preparing said first layer by compression; preparing a two-layer tablet core by pressing onto said first layer said second layer (i) consisting of hydroxypropyl methylcellulose having a viscosity higher than 1000 cP in 2% aqueous solution or (ii) containing 30 to 100% by weight of hydroxypropyl methylcellulose having a viscosity higher than 1000 cP in 2% aqueous solution, 0 to 70% by weight of filling material, 0 to 5% by weight of binding material and 0 to 5% by weight of lubricant in relation to the total weight of said second layer; coating said two-layer tablet core with an ammonium methacrylate copolymer in an amount of 3 to 25 mg/cm 2 in relation to the surface of said two-layer tablet core to form a film-coat on said two-layer tablet core; and establishing at least one bore on said film-coat in contact with said first layer and optionally at least one bore on said film-coat in contact with said second layer.
Claim 58
Dependent Claim
320 words
A process for the preparation of a diffusion-osmotic controlled drug-release pharmaceutical composition comprising a two-layer tablet core, wherein the first layer of said two-layer tablet core contains a therapeutically active agent and hydroxypropyl methylcellulose, wherein the second layer of said two-layer tablet core contains hydroxypropyl methylcellulose, wherein said two-layer tablet core is covered with a polymeric film-coat of an ammonium methacrylate copolymer, the part of said film-coat in contact with said first layer contains at least one bore and the part of said film-coat in contact with said second layer optionally contains at least one bore; said process comprising mixing a therapeutically active agent with 5 to 30% by weight of hydroxypropyl methylcellulose and 0 to 90% by weight of filling material in relation to the total weight of said first layer to form a mixture; mixing at most 5% by weight of lubricant with said mixture directly or after granulating with at most 5% by weight of binding material; preparing said first layer by compression; preparing a two-layer tablet core by pressing onto said first layer said second layer (i) consisting of hydroxypropyl methylcellulose having a viscosity higher than 1000 cP in 2% aqueous solution or (ii) containing 30 to 100% by weight of hydroxypropyl methylcellulose having a viscosity higher than 1000 cP in 2% aqueous solution, 0 to 70% by weight of filling material, 0 to 5% by weight of binding material and 0 to 5% by weight of lubricant in relation to the total weight of said second layer; coating said two-layer tablet core with an ammonium methacrylate copolymer in an amount of 3 to 25 mg/cm 2 in relation to the surface of said two-layer tablet core to form a film-coat on said two-layer tablet core; and establishing at least one bore on said film-coat in contact with said first layer and optionally at least one bore on said film-coat in contact with said second layer.
Claim 59
Dependent Claim
25 words
The process according to claim 50, wherein said ammonium methacrylate copolymer is in an aqueous dispersion or solution with ethanol, isopropanol, acetone or mixtures thereof.
References Cited (Backward Citations)
US5271946A
Cited
US5178866A
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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