Patent US4723958A successfully refreshed from Google Patents.
US4723958A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pulsatile drug delivery system
Assignee: Merck and Co Inc
•
Filing: 1986-05-23
•
Granted: 1988-02-09
•
Expires: 2006-05-23
Abstract
Abstract There is provided a novel drug delivery system which provides for intermittent drug delivery with readily adjustable intervals between drug delivery pulses. This is accomplished by providing a multilayer device in which layers of active drug are readily expandable or erodable when contacted with the environment in which the drug is to be administered. The drug layer is alternated with an inert layer and a multiplicity of such layers are contained within a tube impervious to such environment but provided with an opening into such environment. The multiplicity of such layers is driven along the length of such tube towards the opening. The interval between pulses is determined by the rate the layers are driven along the tube and the sizes of the layers. The duration of the pulse is determined by the rate of expansion or dispersion of the active layer into the environment, wherein the rate of expansion or dispersion is greater than the rate the layers are driven along the tube.
Inventors
- 👤 David G. Pope
- 👤 Alan E. Royce
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:55
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/0002; A61K9/0004; A61M; A61M31/00; A61M31/002
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
178 words
A pulsatile drug delivery system which comprises an elongated container impervious to environmental fluids with an opening end and a driven end with an opening from the inside of the container to the environment at the opening end and a constant driving force operating at the driven end in a direction towards the opening end; a multiplicity of layers arranged lengthwise inside the container substantially filling the inside cross-section of the container and situated between the opening and the constant driving force with an expandable layer closest to the opening end containing one or more of a material which is therapeutically or nutritionally beneficial to be dispensed through the opening into the environment upon contact with the fluids of the environment and the layer adjacent thereto being a spacer layer inert to the fluids of the environment and the remainder of the multiplicity of layers alternating between the expandable layer and the spacer layer and wherein the rate of the dispensing of the expandable layer into the environment is greater than the rate of the constant driving force.
Claim 2
Dependent Claim
178 words
A pulsatile drug delivery system which comprises an elongated container impervious to environmental fluids with an opening end and a driven end with an opening from the inside of the container to the environment at the opening end and a constant driving force operating at the driven end in a direction towards the opening end; a multiplicity of layers arranged lengthwise inside the container substantially filling the inside cross-section of the container and situated between the opening and the constant driving force with an expandable layer closest to the opening end containing one or more of a material which is therapeutically or nutritionally beneficial to be dispensed through the opening into the environment upon contact with the fluids of the environment and the layer adjacent thereto being a spacer layer inert to the fluids of the environment and the remainder of the multiplicity of layers alternating between the expandable layer and the spacer layer and wherein the rate of the dispensing of the expandable layer into the environment is greater than the rate of the constant driving force.
Claim 3
Dependent Claim
25 words
The pulsatile drug delivery system of claim 1 wherein the expandable layer is dispensed through the opening by dispersion into the fluids of the environment.
Claim 4
Dependent Claim
29 words
The pulsatile drug delivery system of claim 1 wherein the expandable layer is dispensed through the opening by expansion due to the absorption of the fluids of the environment.
Claim 5
Dependent Claim
65 words
The pulsatile drug delivery system of claim 1 wherein the expandable layer is one layer of a material which is therapeutically or nutritionally beneficial and a separate layer of a material expandable upon contact with the environment wherein the drug containing material is dispensed through the opening by the force exerted by the expandable layer upon the layer containing the therapeutically or nutritionally beneficial material.
Claim 6
Dependent Claim
28 words
The pulsatile drug delivery system of claim 1 wherein the layers are of varying sizes materials and dispensing characteristics such that a non-uniform series of pulses is provided.
Claim 7
Dependent Claim
26 words
The pulsatile drug delivery system of claim 1 wherein the expandable layer contains a polymeric material which expands upon contact with the fluids of the environment.
Claim 8
Dependent Claim
26 words
The pulsatile drug delivery system of claim 6 wherein the polymeric material is xanthan gum, carboxymethylcellulose, methyl cellulose, alginate, amylose, amylopectin, carboxymethyl starch, acrylics or methyacrylics.
Claim 9
Dependent Claim
19 words
The pulsatile drug delivery system of claim 1 wherein the constant driving force is provided by an osmotic pump.
Claim 10
Dependent Claim
23 words
The pulsatile drug delivery system of claim 8 wherein the osmotic pump is incorporated within the container of the pulsatile drug delivery system.
Claim 11
Dependent Claim
25 words
The pulsatile drug delivery system of claim 1 wherein the opening end of the container is provided with a storage area for the spacer layers.
Claim 12
Dependent Claim
20 words
The pulsatile drug delivery system of claim 10 wherein the opening is a circumferential series of spaces through the container.
Claim 13
Dependent Claim
18 words
The pulsatile drug delivery system of claim 1 wherein the opening comprises the entire cross-section of the container.
Claim 14
Dependent Claim
13 words
The pulsatile drug delivery system of claim 1 which is for oral administration.
Claim 15
Dependent Claim
16 words
The pulsatile drug delivery system of claim 13 which is for oral administration to ruminant animals.
Claim 16
Dependent Claim
27 words
The pulsatile drug delivery system of claim 14 which is provided with densifying agents or variable geometry to cause the retention of the system in the rumen.
Claim 17
Dependent Claim
12 words
The pulsatile drug delivery system of claim 1 which is parenterally implanted.
Claim 18
Dependent Claim
14 words
The pulsatile drug delivery system of claim 16 wherein the parenteral implant is subcutaneous.
Claim 19
Dependent Claim
17 words
The pulsatile drug delivery system of claim 1 wherein the drug being administered is a therapeutic agent.
Claim 20
Dependent Claim
14 words
The pulsatile drug delivery system of claim 18 wherein the therapeutic agent is ivermectin.
Claim 21
Dependent Claim
18 words
The pulsatile drug delivery system of claim 1 wherein the drug being administered is a supplemental nutrient material.
References Cited (Backward Citations)
US3656483A
Cited
US3732865A
Cited
US3760806A
Cited
US3760804A
Cited
US3995632A
Cited
US4671789A
Cited
US4327725A
Cited
US4381780A
Cited
US4623330A
Cited
EP0132102A2
Cited
US4595583A
Cited
US4642230A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-02-08 | 1991-08-10 | 1992-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-08 | 1995-08-10 | 1996-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-08 | 1999-08-10 | 2000-02-09 | $7700.00 | Window Closed / Lapsed |