US4439194A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water and drug delivery system for suppository use
Assignee: Merck and Co Inc
•
Filing: 1981-09-08
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Granted: 1984-03-27
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Expires: 2001-09-08
Abstract
Abstract A drug delivery system designed to deliver water and drug to the site of administration is composed of a core of an aqueous solubulizing system in a wax housing, which melts at body temperature, surrounded by a matrix of drug and water-dispersible excipients. The entire unit may also be coated with a semi-permeable membrane to modulate drug release.
Inventors
- 👤 Richard J. Harwood
- 👤 Joseph V. Bondi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 04:37
CPC Classifications
A; A61; A61M; A61M31/00; A61M31/002; A61K; A61K9/00; A61K9/02; A61K9/025
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
51 words
A drug delivery system comprising an aqueous core in a waxy housing, which housing melts at body temperature, surrounded by a matrix, shaped and sized for rectal or vaginal suppository use, comprising drug which is solubilized by the aqueous solution contained in the waxy core and water soluble or dispersible excipients.
Claim 2
Dependent Claim
51 words
A drug delivery system comprising an aqueous core in a waxy housing, which housing melts at body temperature, surrounded by a matrix, shaped and sized for rectal or vaginal suppository use, comprising drug which is solubilized by the aqueous solution contained in the waxy core and water soluble or dispersible excipients.
Claim 3
Dependent Claim
68 words
The drug delivery system of claim 1, wherein the waxy housing of the aqueous core is composed of a water insoluble waxy material, melting at 35°-37° C. selected from the group consisting of theobromo oil, an eutectic mixture of mono-, di and triglycerides, a mixture of higher melting fractions of coconut oil and palm kernel oil, and a mixture of triglycerides of saturated vegetable fatty acids and monoglycerides.
Claim 4
Dependent Claim
35 words
The drug delivery system of claim 2 wherein the matrix surrounding the aqueous core comprises drug, water-soluble or water dispersible excipients selected from the group consisting of polyethylene glycol, gelatin, starch, lactose and cellulosic derivatives.
Claim 5
Dependent Claim
30 words
The drug delivery system of claim 3 wherein the matrix also comprises an absorption promoter selected from the group consisting of salicylic acid or derivatives, benzalkonium chloride and sodium glycocholate.
Claim 6
Dependent Claim
44 words
The drug delivery system of claims 3 or 4, wherein the matrix also comprises osmotic-active agents selected from the group consisting of sodium chloride, mannitol and sucrose and is coated with a semi-permeable film selected from cellulose acetate, polyvinyl acetate and ethylene vinyl acetate.
References Cited (Backward Citations)
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US1812769A
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US2110962A
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US3490454A
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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) | 1987-03-27 | 1987-09-26 | 1988-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-03-27 | 1991-09-26 | 1992-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-03-27 | 1995-09-26 | 1996-03-27 | $7700.00 | Window Closed / Lapsed |