US4252786A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controlled release tablet
Assignee: ER Squibb and Sons LLC
•
Filing: 1979-11-16
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Granted: 1981-02-24
•
Expires: 1999-11-16
Abstract
Abstract The rate of release of medicament from a controlled release tablet having a polymeric vinylpyrrolidonecarboxyvinyl hydrophilic core is improved by coating the medicament-containing core with a substantially insoluble rupturable film which is water permeable.
Inventors
- 👤 Aaron L. Weiss
- 👤 Richard W. Walton
- 👤 Albert E. de Lorimier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:09
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/20; A61K9/28; A61K9/2806; A61K9/2833; A61K9/286; A61K9/2866; A61K9/2004; A61K9/2022; A61K9/2027
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
191 words
A film coated controlled release medicinal tablet comprising: (i) a compressed matrix comprising an effective amount of medicament dispersed in a blend of 1:10 to 10:1 parts by weight polymeric vinyl pyrrolidone and a carboxyvinyl hydrophilic polymer; and (ii) a substantially water insoluble, water permeable film coating on the compressed matrix, the film coating having a thickness of about 1 to 15 mil. and comprising a blend of hydrophobic polymer selected from the group consisting of cellulose ethyl esters, cellulose acetate, polyvinyl alcohol-maleic anhydride copolymers, β-pinene polymers, glycerol esters of wood resins, and hydroxypropyl methyl cellulose phthalate, and hydrophilic polymer selected from the group consisting of cellulose methyl ethers, hydroxypropyl cellulose, cellulose acetate phthalate and polyvinyl alcohol, wherein the weight ratio of hydrophilic polymer to hydrophobic polymer is within the range of about 4:1 to about 1:4; wherein the release rate of medicament is initially controlled primarily by the film coating and after rupture or erosion of the film the release rate of medicament is controlled by the compressed matrix; and wherein the release of the medicament through the film begins within about one hour after the tablet has been ingested.
Claim 2
Dependent Claim
191 words
A film coated controlled release medicinal tablet comprising: (i) a compressed matrix comprising an effective amount of medicament dispersed in a blend of 1:10 to 10:1 parts by weight polymeric vinyl pyrrolidone and a carboxyvinyl hydrophilic polymer; and (ii) a substantially water insoluble, water permeable film coating on the compressed matrix, the film coating having a thickness of about 1 to 15 mil. and comprising a blend of hydrophobic polymer selected from the group consisting of cellulose ethyl esters, cellulose acetate, polyvinyl alcohol-maleic anhydride copolymers, β-pinene polymers, glycerol esters of wood resins, and hydroxypropyl methyl cellulose phthalate, and hydrophilic polymer selected from the group consisting of cellulose methyl ethers, hydroxypropyl cellulose, cellulose acetate phthalate and polyvinyl alcohol, wherein the weight ratio of hydrophilic polymer to hydrophobic polymer is within the range of about 4:1 to about 1:4; wherein the release rate of medicament is initially controlled primarily by the film coating and after rupture or erosion of the film the release rate of medicament is controlled by the compressed matrix; and wherein the release of the medicament through the film begins within about one hour after the tablet has been ingested.
Claim 3
Dependent Claim
50 words
A tablet as in claim 1 wherein the compressed matrix comprises an effective amount of medicament which is at least 50% of the total tablet weight dispersed in a polymer blend comprising 1:10 to 10:1 parts by weight of polyvinyl pyrrolidone and polymer of acrylic acid cross-linked with polyallyl sucrose.
Claim 4
Dependent Claim
20 words
A tablet as in claim 1 wherein the hydrophobic polymer is ethyl cellulose and the hydrophilic polymer is methyl cellulose.
Claim 5
Dependent Claim
20 words
A tablet as in claim 1 wherein the hydrophobic polymer is ethyl cellulose and the hydrophilic polymer is hydroxypropylmethyl cellulose.
Claim 6
Dependent Claim
34 words
A tablet as in claim 1 wherein the matrix comprises polyvinyl pyrrolidone and a carboxyvinyl hydrophilic polymer of acrylic acid cross-linked with polyalkenyl polyether and the film coating comprises ethyl cellulose and hydroxypropylmethyl cellulose.
Claim 7
Dependent Claim
34 words
A tablet as in claim 1 wherein the matrix comprises polyvinyl pyrrolidone and a carboxyvinyl hydrophilic polymer of acrylic acid cross-linked with polyalkenyl polyether and the film coating comprises ethyl cellulose and methyl cellulose.
Claim 8
Dependent Claim
14 words
A tablet as in claim 1 wherein the medicament is procainamide or salt thereof.
Claim 9
Dependent Claim
11 words
A tablet as in claim 1 wherein the medicament is cephradine.
Claim 10
Dependent Claim
32 words
A tablet as in claim 1 wherein the matrix comprises medicament, polyvinyl pyrrolidone and polymer of acrylic acid cross-linked with polyallyl sucrose and the film coating comprises ethyl cellulose and hydroxypropylmethyl cellulose.
Claim 11
Dependent Claim
32 words
A tablet as in claim 1 wherein the matrix comprises medicament, polyvinyl pyrrolidone and polymer of acrylic acid cross-linked with polyallyl sucrose and the film coating comprises ethyl cellulose and methyl cellulose.
Claim 12
Dependent Claim
14 words
A tablet as in claim 10 wherein the medicament is procainamide or salt thereof.
Claim 13
Dependent Claim
17 words
A tablet as in claim 1 wherein the film is about 3 to 7 mil. in thickness.
Claim 14
Dependent Claim
31 words
A tablet as in claim 1 wherein the ratio of hydrophilic polymer to hydrophobic polymer is about 1.5:1 to 1:1 and the film is about 3 to 7 mil. in thickness.
Claim 15
Dependent Claim
14 words
A tablet as in claim 2 wherein the medicament is procainamide or salt thereof.
Claim 16
Dependent Claim
20 words
A tablet as in claim 2 wherein the hydrophobic polymer is ethyl cellulose and the hydrophilic polymer is methyl cellulose.
Claim 17
Dependent Claim
20 words
A tablet as in claim 2 wherein the hydrophobic polymer is ethyl cellulose and the hydrophilic polymer is hydroxypropylmethyl cellulose.
Claim 18
Dependent Claim
25 words
A tablet as in claim 2 wherein the medicament is procainamide hydrochloride, the hydrophobic polymer is ethyl cellulose and the hydrophilic polymer is hydroxypropylmethyl cellulose.
Claim 19
Dependent Claim
31 words
A tablet as in claim 14 wherein the ratio of hydrophilic polymer to hydrophobic polymer is about 1.5:1 to 1:1 and the film is about 3 to 7 mil. in thickness.
Claim 20
Dependent Claim
92 words
A tablet as in claim 2 wherein said polymer blend comprises polyvinyl pyrrolidone and polymer of acrylic acid cross linked with polyallyl sucrose in a ratio of about 1.5:1, the ratio of said last named polymer to said medicament is about 0.1 to 0.45:1, said water soluble hydrophilic polymer is hydroxypropylmethylcellulose and said slightly water soluble hydrophobic polymer is ethyl cellulose in a ratio of about 1:1 to 1.5 to 1 and said film is about 3 to 7 mil. in thickness and comprises about 5 to 15% of finished tablet weight.
Claim 21
Dependent Claim
12 words
A tablet as in claim 19 wherein the medicament is procainamide hydrochloride.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-24 | 1984-08-25 | 1985-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-24 | 1988-08-25 | 1989-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-24 | 1992-08-25 | 1993-02-24 | $7700.00 | Window Closed / Lapsed |