← Back to Patent Explorer
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
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

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 20:12
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

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag