Patent US4874388A successfully refreshed from Google Patents.
US4874388A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multi-layer delivery system
Assignee: Alza Corp
•
Filing: 1987-06-25
•
Granted: 1989-10-17
•
Expires: 2007-06-25
Abstract
Abstract A dispenser for use in a fluid environment having a rigid housing containing a fluid activated driving member, a plurality of drug containing layers and an outlet means by which drug is dispensed to the environment. The housing adjacent to the layers is fluid impermeable and the housing adjacent to the driving member is fluid permeable or has an open area by which fluid can contact the driving member. O048743884
Inventors
- 👤 Patrick S. L. Wong
- 👤 Felix Theeuwes
- 👤 James B. Eckenhoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 21:55
CPC Classifications
A; A61; A61M; A61M31/00; A61M31/002; A61K; A61K9/00; A61K9/0002; A61K9/0004
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
155 words
A drug dispenser for use in a fluid-containing environment comprising, in combination: a. a rigid housing having an outlet at one end thereof; b. a fluid activated driving member within a portion of said housing proximate the end of said housing opposite to said outlet and in contact with said housing, at least that portion of the housing contacting the driving member having a predetermined permeation rate to the environmental fluid; c. a first set of drug layers longitudinally disposed within said housing between said driving means and said outlet; d. a second set of layers longitudinally disposed within said housing and alternating with said first drug layers; and e. an expansion chamber defining an empty volume within said housing between the drug layer most proximate the outlet and the outlet; whereby said drug layers must be displaced through the expansion chamber by said driving means after exposure of said dispenser to the fluid environment.
Claim 2
Dependent Claim
155 words
A drug dispenser for use in a fluid-containing environment comprising, in combination: a. a rigid housing having an outlet at one end thereof; b. a fluid activated driving member within a portion of said housing proximate the end of said housing opposite to said outlet and in contact with said housing, at least that portion of the housing contacting the driving member having a predetermined permeation rate to the environmental fluid; c. a first set of drug layers longitudinally disposed within said housing between said driving means and said outlet; d. a second set of layers longitudinally disposed within said housing and alternating with said first drug layers; and e. an expansion chamber defining an empty volume within said housing between the drug layer most proximate the outlet and the outlet; whereby said drug layers must be displaced through the expansion chamber by said driving means after exposure of said dispenser to the fluid environment.
Claim 3
Dependent Claim
40 words
The dispenser of claim 1 wherein the portion of said rigid housing proximate said expansion means has a permeation rate to said environmental fluid substantially greater than the permeation rate of the portion of the housing proximate said driving means.
Claim 4
Dependent Claim
26 words
The dispenser of claim 2 wherein the portion of said housing between said driving means and said expansion means is substantially impermeable to said environmental fluid.
Claim 5
Dependent Claim
22 words
The dispenser of claim 3 wherein said first set of layers contains means for generating gas upon contact with said environmental fluid.
Claim 6
Dependent Claim
44 words
The dispenser of claim 1 wherein said second set of layers contains a drug different from the drug in said first set of layers and is formulated to release a substantial portion of its drug to the fluid environment after displacement through the outlet.
Claim 7
Dependent Claim
14 words
The dispenser of claim 1 wherein said plurality of drug layers contain different drugs.
Claim 8
Dependent Claim
18 words
The dispenser of claim 6 wherein said layers further comprise excipients to control the erosion of said layers.
Claim 9
Dependent Claim
15 words
The dispenser of claim 1 wherein said drug layers are separated by non-drug containing layers.
Claim 10
Dependent Claim
14 words
The dispenser of claim 1 wherein said driving member comprises a fluid swellable composition.
Claim 11
Dependent Claim
14 words
The dispenser of claim 1 wherein said driving member comprises an osmotically effective solute.
Claim 12
Dependent Claim
23 words
The dispenser of claim 10 wherein the portion of said housing in contact with said solute is permeable to the passage of fluid.
Claim 13
Dependent Claim
18 words
The dispenser of claim 11 wherein said solute and said drug layers are separated by a flexible membrane.
Claim 14
Dependent Claim
14 words
The dispenser of claim 1 wherein said driving member comprises an elementary osmotic pump.
Claim 15
Dependent Claim
20 words
The dispenser of claim 13 wherein said elementary osmotic pump and said drug layers are separated by a movable piston.
Claim 16
Dependent Claim
14 words
The dispenser of claim 1 wherein said driving member comprises a gas generating composition.
Claim 17
Dependent Claim
20 words
The dispenser of claim 15 wherein said gas generating composition and said drug layers are separated by a semipermeable membrane.
Claim 18
Dependent Claim
11 words
The dispenser of claim 1 which further comprises a density element.
Claim 19
Dependent Claim
24 words
The dispenser of claim 1 wherein said first set of layers deliver drug to the environment by bursting upon contact with said outlet means.
Claim 20
Dependent Claim
30 words
The dispenser of claim 18 wherein said first set of layers contain a drug selected from the group consisting of: bithionol sulfoxide, oxyclozanide, clioxanide, niclofolan, nitroxinil, rafoxanide, benzimidazole and diamfenetide.
Claim 21
Dependent Claim
16 words
The dispenser of claim 18 wherein said second set of layers contain ivermectin suspended in wax.
Claim 22
Dependent Claim
11 words
The dispenser of claim 20 which further comprises a density element.
Claim 23
Dependent Claim
18 words
The dispenser of claim 4 wherein said first set of layers are comprised of a hydrophilic drug composition.
Claim 24
Dependent Claim
17 words
The dispenser of claim 22 wherein said second set of layers are comprised of a hydrophobic composition.
Claim 25
Dependent Claim
19 words
The dispenser of claim 22 wherein said hydrophilic drug composition is comprised of a drug and an osmotic agent.
Claim 26
Dependent Claim
20 words
The dispenser of claim 22 wherein said hydrophilic drug composition is comprised of a drug and a heat sensitive agent.
Claim 27
Dependent Claim
13 words
The dispenser of claim 23 wherein said hydrophobic composition further comprises a drug.
References Cited (Backward Citations)
US1736078A
Cited
US2620061A
Cited
US2853206A
Cited
US3410455A
Cited
US3565284A
Cited
US3656483A
Cited
US3995631A
Cited
US4034756A
Cited
US3845882A
Cited
US3844445A
Cited
US3845770A
Cited
US4177256A
Cited
US3995632A
Cited
US4111202A
Cited
US4251506A
Cited
US4220152A
Cited
US4220153A
Cited
US4578264A
Cited
US4203441A
Cited
US4264573A
Cited
US4265874A
Cited
US4344929A
Cited
US4320759A
Cited
US4326522A
Cited
DE3021848A1
Cited
US4350271A
Cited
US4381780A
Cited
US4410328A
Cited
US4623330A
Cited
US4449983A
Cited
WO1984000282A1
Cited
US4612008A
Cited
US4578263A
Cited
US4627850A
Cited
US4589575A
Cited
US4595583A
Cited
US4612186A
Cited
US4642230A
Cited
WO1986000519A1
Cited
US4624847A
Cited
US4723958A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-16 | 1993-04-17 | 1993-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-16 | 1997-04-17 | 1997-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-16 | 2001-04-17 | 2001-10-17 | $7700.00 | Window Closed / Lapsed |