US4900755A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controlled release combination of carbidopa/levodopa
Assignee: Merck and Co Inc
•
Filing: 1989-02-24
•
Granted: 1990-02-13
•
Expires: 2009-02-24
Abstract
Abstract A matrix or monolithic drug delivery system for the controlled release of carbidopa and levodopa consists of the two drugs uniformly dispersed in a polymer vehicle at a concentration that is greater than the solubility of either drug in the polymer. Treatment of parkinsonism with the controlled release formulation provides several advantages over treatment with the standard carbidopa/levidopa combinations presently employed.
Inventors
- 👤 Robert E. Dempski
- 👤 Edward C. Scholtz
- 👤 Donald W. Nibbelink
- 👤 Scott A. Reines
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:19
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/20; A61K9/2004; A61K9/2022; A61K9/2027; A61K31/00; A61K31/185; A61K31/19; A61K31/195; A61K9/205; A61K9/2054
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
57 words
A controlled release oral dosage formulation comprising a uniform dispersion of 25-100 mg of carbidopa and 100-400 mg of levodopa in a polymer vehicle comprising 5-25 mg of a water-soluble hydroxypropylcellulose polymer and 2-50 mg of a less water-soluble polyvinylacetatecrotonic acid copolymer whereby, following administration, the carbidopa and levodopa are released slowly and simultaneously from the formulation.
Claim 2
Dependent Claim
57 words
A controlled release oral dosage formulation comprising a uniform dispersion of 25-100 mg of carbidopa and 100-400 mg of levodopa in a polymer vehicle comprising 5-25 mg of a water-soluble hydroxypropylcellulose polymer and 2-50 mg of a less water-soluble polyvinylacetatecrotonic acid copolymer whereby, following administration, the carbidopa and levodopa are released slowly and simultaneously from the formulation.
Claim 3
Dependent Claim
25 words
The formulation of claim 1 comprising 200 mg. of levodopa and 50 mg. of carbidopa or 100 mg. of levodopa and 25 mg. of carbidopa.
Claim 4
Dependent Claim
28 words
The formulation of claim 1 comprising 200 mg of levodopa, 50 mg of carbidopa, 5-6.5 mg of vinyl acetate-crotonic acid copolymer and about 17 mg of hydroxypropyl cellulose.
Claim 5
Dependent Claim
26 words
The formulation of claim 1 comprising 100 mg of levodopa, 25 mg of carbidopa, 2.5 mg of vinylacetatecrontic acid copolymer and about 8.5 mg of hydroxypropylcellulose.
References Cited (Backward Citations)
US3995058A
Cited
US4021555A
Cited
US4389415A
Cited
US4190672A
Cited
US4469695A
Cited
US4469694A
Cited
US4469693A
Cited
US4329356A
Cited
US4421767A
Cited
US4413012A
Cited
US4424235A
Cited
US4497826A
Cited
US4446138A
Cited
US4440740A
Cited
US4529603A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-02-12 | 1993-08-14 | 1994-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-12 | 1997-08-14 | 1998-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-12 | 2001-08-14 | 2002-02-13 | $7700.00 | Window Closed / Lapsed |