US4264573A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pharmaceutical formulation for slow release via controlled surface erosion
Assignee: Rowell Laboratories Inc
•
Filing: 1979-05-21
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Granted: 1981-04-28
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Expires: 1999-05-21
Abstract
Abstract A pharmaceutical composition in tablet form for oral administration comprises: (a) 30-90% by weight of an active ingredient having a water solubility (20° C.) of about 1/10-1/500 (w/w); (b) 1-40% by weight of an excipient which is pharmaceutically acceptable in oral tablets and which has a water solubility (20° C.) of about 1/1-1/20 (w/w); (c) 0-20% by weight of a binder which is pharmaceutically acceptable in oral tablets; (d) 0-50% by weight of an excipient which is pharmaceutically acceptable in oral tablets and which has a water solubility (20° C.) of about 1/1-1/5 (w/w); (e) 0.5-5% by weight of a die wall lubricant pharmaceutically acceptable in oral tablets; (f) 0-5% by weight of a surface active agent pharmaceutically acceptable in oral tablets; and (g) 0-1.0% by weight of a disintegration agent pharmaceutically acceptable in oral tablets; whereby the active ingredient has a slow in vivo release rate due to controlled surface erosion of the tablet.
Inventors
- 👤 David R. Powell
- 👤 Vithal K. Patel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:13
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/20; A61K9/2004
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
156 words
A pharmaceutical composition in tablet form for oral administration consisting essentially of (a) 70-80 wt.% of lithium carbonate; (b) 5-15 wt.% of an excipient which is pharmaceutically acceptable in oral tablets and which has a water solubility (20° C.) of about 1/1-1/20 (w/w); (c) 2-7 wt.% of a binder which is pharmaceutically acceptable in oral tablets; (d) 5-15 wt.% of an excipient which is pharmaceutically acceptable in oral tablets and which has a water solubility (20° C.) of about 1/1-1/5 (w/w); (e) 0.9-3.3 wt.% of a dye wall lubricant pharmaceutically acceptable in oral tablets; (f) 0.1-0.2 wt% of a surface active agent pharmaceutically acceptable in oral tablets; and (g) 0.15-0.35 wt.% of a disintegration agent pharmaceutically acceptable in oral tablets; whereby the active ingredient has a slow zero order in vivo release rate and a plasma concentration/time curve of substantially the same shape as that of FIG. 1, due to controlled surface erosion of the tablet.
Claim 2
Dependent Claim
156 words
A pharmaceutical composition in tablet form for oral administration consisting essentially of (a) 70-80 wt.% of lithium carbonate; (b) 5-15 wt.% of an excipient which is pharmaceutically acceptable in oral tablets and which has a water solubility (20° C.) of about 1/1-1/20 (w/w); (c) 2-7 wt.% of a binder which is pharmaceutically acceptable in oral tablets; (d) 5-15 wt.% of an excipient which is pharmaceutically acceptable in oral tablets and which has a water solubility (20° C.) of about 1/1-1/5 (w/w); (e) 0.9-3.3 wt.% of a dye wall lubricant pharmaceutically acceptable in oral tablets; (f) 0.1-0.2 wt% of a surface active agent pharmaceutically acceptable in oral tablets; and (g) 0.15-0.35 wt.% of a disintegration agent pharmaceutically acceptable in oral tablets; whereby the active ingredient has a slow zero order in vivo release rate and a plasma concentration/time curve of substantially the same shape as that of FIG. 1, due to controlled surface erosion of the tablet.
Claim 3
Dependent Claim
45 words
The pharmaceutical composition of claim 1 consisting essentially of: 70-80 wt.% of lithium carbonate; 5-15 wt.% of sodium chloride; 2-7 wt.% of polyvinylpyrrolidone; 5-15 wt.% of sorbitol; 0.9-3.3 wt.% of calcium stearate; 0.1-0.2 wt.% of sodium lauryl sulfate; and 0.15-0.35 wt.% of sodium starch glycolate.
Claim 4
Dependent Claim
51 words
The pharmaceutical composition of claim 2 consisting essentially of the following approximate amounts of ingredients: 300 mg of lithium carbonate; 40 mg of sodium chloride; 15 mg of polyvinylpyrrolidone; 9.4 mg of calcium stearate; 0.6 mg of sodium lauryl sulfate; 40 mg of sorbitol; and 1 mg of sodium starch glycolate.
Claim 5
Dependent Claim
23 words
The pharmaceutical composition of claim 1, 2 or 3 which is in the form of a tablet of a hardness of 5-20 kg.
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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) | 1984-04-27 | 1984-10-27 | 1985-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-04-27 | 1988-10-27 | 1989-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-04-27 | 1992-10-27 | 1993-04-28 | $7700.00 | Window Closed / Lapsed |