Patent US5019398A successfully refreshed from Google Patents.
US5019398A
Expired / Lapsed
US
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Pharmaceutical composition providing the sustained-release of valproic acid
Assignee: Sanofi Aventis France
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Filing: 1990-02-23
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Granted: 1991-05-28
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Expires: 2010-02-23
Abstract
Abstract The object of the invention is a tablet sustaining release for more than 8 hours, the active ingredient of which is constituted by the complex formed between one mole of valproic acid and one mole of sodium valproate.
Inventors
- 👤 Georges Daste
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:58
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/20; A61K9/28; A61K9/2886; A61K31/00; A61K31/185; A61K31/19; A61K31/20; A61K9/2806; A61K9/2813; A61K9/2833; A61K9/286; A61K9/2866
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
75 words
A tablet sustaining release for more than 8 hours, the active ingredient of which is constituted by the complex formed between one mole of valproic acid and one mole of sodium valproate, and excipients comprising 8% to 10% by weight relative to the weight of the complex of a matrix of hydroxypropylmethylcellulose of viscosity from 8000 to 12000 mPa.s, and 8% to 10% by weight relative to the weight of the complex of hydrated silica.
Claim 2
Dependent Claim
75 words
A tablet sustaining release for more than 8 hours, the active ingredient of which is constituted by the complex formed between one mole of valproic acid and one mole of sodium valproate, and excipients comprising 8% to 10% by weight relative to the weight of the complex of a matrix of hydroxypropylmethylcellulose of viscosity from 8000 to 12000 mPa.s, and 8% to 10% by weight relative to the weight of the complex of hydrated silica.
Claim 3
Dependent Claim
24 words
The tablet of claim 1, comprising in addition from 1 to 2% by weight of colloidal silica relative to the weight of the complex.
Claim 4
Dependent Claim
43 words
A tablet according to claim 1, which is coated with a varnish composed of 2 layers, the first of which is essentially formed of hydroxypropylmethylcellulose of viscosity between 5 and 20 mPa.s and the external layer is based on film-forming polyacrylates or polymethacrylates.
Claim 5
Dependent Claim
43 words
A tablet according to claim 2, which is coated with a varnish composed of 2 layers, the first of which is essentially formed of hydroxypropylmethylcellulose of viscosity between 5 and 20 mPa.s and the external layer is based on film-forming polyacrylates or polymethacrylates.
Claim 6
Dependent Claim
42 words
A unit dose tablet comprising 538 mg of valproic acid and sodium valproate complex, 45 mg to 50 mg of a matrix of hydroxypropylmethylcellulose of viscosity about 10000 mPa.s, 45 to 50 mg of hydrated silica and 3 mg of colloidal silica.
Claim 7
Dependent Claim
42 words
A unit dose tablet comprising 538 mg of valproic acid and sodium valproate complex, 45 mg to 50 mg of a matrix of hydroxypropylmethylcellulose of viscosity about 10000 mPa.s, 45 to 50 mg of hydrated silica and 3 mg of colloidal silica.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-05-27 | 1994-11-26 | 1995-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-05-27 | 1998-11-26 | 1999-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-05-27 | 2002-11-26 | 2003-05-28 | $7700.00 | Window Closed / Lapsed |