US4792452A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controlled release formulation
Assignee: ER Squibb and Sons LLC
•
Filing: 1987-07-28
•
Granted: 1988-12-20
•
Expires: 2007-07-28
Abstract
Abstract A controlled release pharmaceutical formulation is provided which releases a pharmaceutical of a basic character at a controlled rate regardless of the pH of the environment, which formulation includes a basic pharmaceutical, up to about 45% by weight of a pH dependent polymer which is a salt of alginic acid, such as sodium alginate, up to about 35% by weight of a pH-independent hydrocarbon gelling agent having a viscosity of up to about 100,000 centipoises in 2% solution at 20° C., binder and excipients.
Inventors
- 👤 John R. Howard
- 👤 Peter Timmins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:10
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/20; A61K9/2004; A61K9/2022; A61K9/205; A61K9/2054
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
138 words
A controlled release pharmaceutical formulation from which a pharmaceutical of a basic character is released at a controlled rate irrespective of the pH of the environment, consisting essentially of a pharmaceutical of a basic character, a pH-dependent polymer which is a salt of alginic acid, in an amount of from about 15 to about 45% by weight of the formulation, said salt of alginic acid having a viscosity of within the range of from about 4 to about 500 centipoises in 1% solution at 25° C.; a pH-independent hydrocolloid gelling agent having a viscosity within the range of from about 50 to about 100,000 centipoises in 2% solution at 20° C., in an amount within the range of from about 3 to about 35% by weight of the formulation, and binder, said formulation being free of calcium ion.
Claim 2
Dependent Claim
138 words
A controlled release pharmaceutical formulation from which a pharmaceutical of a basic character is released at a controlled rate irrespective of the pH of the environment, consisting essentially of a pharmaceutical of a basic character, a pH-dependent polymer which is a salt of alginic acid, in an amount of from about 15 to about 45% by weight of the formulation, said salt of alginic acid having a viscosity of within the range of from about 4 to about 500 centipoises in 1% solution at 25° C.; a pH-independent hydrocolloid gelling agent having a viscosity within the range of from about 50 to about 100,000 centipoises in 2% solution at 20° C., in an amount within the range of from about 3 to about 35% by weight of the formulation, and binder, said formulation being free of calcium ion.
Claim 3
Dependent Claim
37 words
The formulation as defined in claim 1 wherein the pH-dependent salt of alginic acid is employed in a weight ratio to the pH-independent hydrocolloid gelling agent of within the range of from about 0.1:1 to about 10:1.
Claim 4
Dependent Claim
60 words
The formulation as define in claim 1 wherein said pH-dependent salt of alginic acid is employed in an amount within the range of from about 20 to about 35% by weight of the formulation and the pH-independent hydrocolloid gelling agent is employed in an amount within the range of from about 3 to about 20% by weight of said formulation.
Claim 5
Dependent Claim
31 words
The formulation as defined in claim 1 wherein said pharmaceutical of a basic character is employed in an amount of from about 20 to about 75% by weight of said formulation.
Claim 6
Dependent Claim
13 words
The formulation as defined in claim 1 in the form of a tablet.
Claim 7
Dependent Claim
18 words
The formulation as defined in claim 1 wherein said pharmaceutical of a basic character is a calcium antagonist.
Claim 8
Dependent Claim
37 words
The formulation as defined in claim 6 wherein said calcium antagonist is a salt of verapamil, a salt of diltiazem, a salt of nicardipine, a salt of nifedipine, a salt of gallapomil or a salt of cinnarizine.
Claim 9
Dependent Claim
30 words
The formulation as defined in claim 1 wherein said pharmaceutical of a basic character is a beta blocker, antihistamine, sympathomimetic, beta adrenergic agonist or bronchodilator, or central nervous system drug.
Claim 10
Dependent Claim
79 words
The formulation as defined in claim 8 wherein said beta blocker is a salt of propranolol, a salt of metoprolol, or a salt of nadolol, said antihistamine is a salt of chlorpheniramine, a salt of diphenhydramine, said sympathomimetic is a salt of phenylpropanolamine or a salt of pseudoephedrine, said beta adrenergic agonist is a salt of salbutamol, or a salt of terbutaline, and said central nervous system drug is a salt of thioridazine, a salt of trifluoperazine, or chlorpromazine.
Claim 11
Dependent Claim
31 words
The formulation as defined in claim 1 wherein said hydrocolloid gelling agent is hydroxypropylmethyl cellulose, methyl cellulose, hydroxypropyl cellulose, or a mixture of two or more of such hydrocolloid gelling agents.
Claim 12
Dependent Claim
29 words
The formulation as defined in claim 1 wherein said binder is hydroxypropylmethyl cellulose having a viscosity of from about 5 to about 15 centipoises, hydrolyzed gelatin or polyvinyl pyrrolidone.
Claim 13
Dependent Claim
13 words
The formulation as defined in claim 1 further including one or more excipients.
Claim 14
Dependent Claim
21 words
The formulation as defined in claim 12 wherein said excipient is microcrystalline cellulose, lactose, sugar, mannitol, sorbitol, inorganic salts or cellulose.
Claim 15
Dependent Claim
11 words
The formulation as defined in claim 1 further including a lubricant.
Claim 16
Dependent Claim
16 words
The formulation as defined in claim 14 wherein said lubricant is magnesium stearate or stearic acid.
Claim 17
Dependent Claim
19 words
The formulation as defined in claim 1 wherein said salt of alginic acid is sodium alginate or potassium alginate.
Claim 18
Dependent Claim
34 words
The formulation as defined in claim 1 wherein the salt of alginic acid has a viscosity of within the range of from about 4 to about 350 centipoises in 1% solution at 25° C.
Claim 19
Dependent Claim
15 words
The formulation as defined in claim 1 containing alginic acid salts of two different viscosities.
Claim 20
Dependent Claim
12 words
The formulation as defined in claim 1 further including a coating layer.
Claim 21
Dependent Claim
75 words
The formulation as defined in claim 1 wherein said pharmaceutical of a basic character is verapamil hydrochloride, said salt of alginic acid is sodium alginate, said hydrocolloid gelling agent is hydroxypropylmethyl cellulose having a viscosity of from about 50 to about 100,000 centipoises, said binder is hydroxypropylmethyl cellulose having a viscosity of from about 5 to about 15 centipoises, further including microcrystalline cellulose and lactose as binders-excipients and further including magnesium stearate as a lubricant.
References Cited (Backward Citations)
US4610870A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-12-20 | 1992-06-20 | 1992-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-12-20 | 1996-06-20 | 1996-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-12-20 | 2000-06-20 | 2000-12-20 | $7700.00 | Window Closed / Lapsed |