US4680312A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stable prostaglandin E gels utilizing colloidal silicon dioxide as a gel-forming agent
Assignee: Pharmacia and Upjohn Co
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Filing: 1984-11-21
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Granted: 1987-07-14
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Expires: 2004-11-21
Abstract
Abstract The present invention provides an improved class of stable gels of prostaglandin E compounds prepared from solutions of prostaglandin E compounds in a pharmaceutically acceptable, stabilizing organic solvent, e.g., triacetin, gelled by the addition of colloidal silicon dioxide.
Inventors
- 👤 Brian S. Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:13
CPC Classifications
A; A61; A61K; A61K31/00; A61K31/557
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
55 words
In a stable dosage form of PGE 2 consisting essentially of PGE 2 in triacetin, an improvement which comprises: colloidal silicon dioxide (CSD) as a gel forming additive thereto in a concentration by weight of CSD in said stable dosage form from about not less than 8 percent to about not more than 15 percent.
Claim 2
Dependent Claim
55 words
In a stable dosage form of PGE 2 consisting essentially of PGE 2 in triacetin, an improvement which comprises: colloidal silicon dioxide (CSD) as a gel forming additive thereto in a concentration by weight of CSD in said stable dosage form from about not less than 8 percent to about not more than 15 percent.
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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) | 1990-07-13 | 1991-01-12 | 1991-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-13 | 1995-01-12 | 1995-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-13 | 1999-01-12 | 1999-07-14 | $7700.00 | Window Closed / Lapsed |