← Back to Patent Explorer
US4685918A Expired / Lapsed US ⏱️ 0.0 years remaining

Lipid osmotic pump

Assignee: Merck and Co Inc
•
Filing: 1985-02-01
•
Granted: 1987-08-11
•
Expires: 2005-02-01
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The instant invention is directed to a lipid osmotic pump, comprising: (A) a core, comprising: (i) a beneficial amount of at least one substantially water insoluble active agent which is lipid soluble and/or lipid wettable; (ii) a sufficient amount of at least one water immiscible lipid carrier, which is liquid at the temperature of intended use, to dissolve and/or suspend said active agent; and (iii) a sufficient amount of at least one osmotic agent to ensure release of said lipid carrier from the pump; and (B) surrounded by a water insoluble wall: (i) having a thickness of about 1 to 1000 microns; (ii) which is preferentially wetted by said lipid carrier over an aqueous solution of said osmotic agent; (iii) having a water permeability of about 1x10-18 to 4x10-15 cm3 sec/g; (iv) prepared from at least one polymer permeable to water but substantially impermeable to said osmotic agent; and (v) having a means for said active agent and lipid carrier to be released through said water insoluble wall.

Inventors

  • 👤 Gordon L. Amidon
  • 👤 Takeru Higuchi
  • 👤 Jennifer B. Dressman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 10:29
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/48; A61K9/50; A61K9/5005; A61K9/5021; A61K9/5036; A61K9/5042; A61K9/0002; A61K9/0004

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 27 words
A lipid osmotic pump, for the controlled delivery of a substantially water insoluble active agent into an aqueous environment, comprising: (A) a core, comprising an admixture of:
Claim 2
Dependent Claim 27 words
A lipid osmotic pump, for the controlled delivery of a substantially water insoluble active agent into an aqueous environment, comprising: (A) a core, comprising an admixture of:
Claim 3
Dependent Claim 212 words
(i) a beneficial amount of at least one substantially water insoluble active agent which is lipid soluble and/or lipid wettable; (ii) a sufficient amount of at least one water immiscible lipid carrier, which is liquid at the temperature of intended use, to dissolve and/or suspend said active agent; and (iii) a sufficient amount of at least one osmotic agent to ensure release of said lipid carrier from the pump; and (B) surrounded by a water insoluble wall; (i) having a thickness of about 1 to 1000 microns; (ii) which is preferentially wetted by said lipid carrier over an aqueous solution of said osmotic agent; (iii) having a water permeability of about 1×10 -18 to 4×10 -15 cm 3 sec/g; (iv) prepared from atleast some polymer permeable to waster but substantially impermeable to said osmotic agent; and (v) having a means for said active agent to be released through said water insoluble wall; (C) wherein at the temperature of use, the lipid carrier is liquid and retains the lipid soluble or lipid wettable agent in a dissolved or suspended state so that upon the dissolution of the osmotic agent in the imbibed water the lipid carrier and the dissolved or suspended active agent is released from the osmotic pump at a controlled rate.
Claim 4
Dependent Claim 212 words
(i) a beneficial amount of at least one substantially water insoluble active agent which is lipid soluble and/or lipid wettable; (ii) a sufficient amount of at least one water immiscible lipid carrier, which is liquid at the temperature of intended use, to dissolve and/or suspend said active agent; and (iii) a sufficient amount of at least one osmotic agent to ensure release of said lipid carrier from the pump; and (B) surrounded by a water insoluble wall; (i) having a thickness of about 1 to 1000 microns; (ii) which is preferentially wetted by said lipid carrier over an aqueous solution of said osmotic agent; (iii) having a water permeability of about 1×10 -18 to 4×10 -15 cm 3 sec/g; (iv) prepared from atleast some polymer permeable to waster but substantially impermeable to said osmotic agent; and (v) having a means for said active agent to be released through said water insoluble wall; (C) wherein at the temperature of use, the lipid carrier is liquid and retains the lipid soluble or lipid wettable agent in a dissolved or suspended state so that upon the dissolution of the osmotic agent in the imbibed water the lipid carrier and the dissolved or suspended active agent is released from the osmotic pump at a controlled rate.
Claim 5
Dependent Claim 36 words
The lipid osmotic pump of claim 1, wherein said means for said active agent to be released through said water insoluble wall is a hole connecting said core with the exterior of said water insoluble wall.
Claim 6
Dependent Claim 31 words
The lipid osmotic pump of claim 1, wherein said water insoluble wall is microporous and, thus, provides a means for said active agent to be released through said water insoluble wall.
Claim 7
Dependent Claim 33 words
The lipid osmotic pump of claim 1, wherein said microporous, water impermeable, wall is made by dispersing throughout said wall 5 to 100 parts of pore forming additive per 150 parts wall polymer.
Claim 8
Dependent Claim 35 words
The lipid osmotic pump of claim 4, wherein said pore forming additive is selected from the group consisting of alkali metal salts, alkaline earth metal salts, transition metal salts, organic acids, saccharides, and organic polyols.
Claim 9
Dependent Claim 43 words
The lipid osmotic pump of claim 3, wherein said microporous, water insoluble, wall is made by a process selected from the group consisting of etched nuclear tracking, solvent evaporation gas formation, cold stretching, hot stretching, solvent leaching, ion exchange reaction, and polyelectrolyte processes.
Claim 10
Dependent Claim 43 words
The lipid osmotic pump of claim 1, wherein said water insoluble wall is comprised of at least two different polymer layers with the polymer closest to the core being preferentially wetted by said lipid carrier over an aqueous solution of said osmotic agent.
Claim 11
Dependent Claim 17 words
The lipid osmotic pump of claim 1, wherein said lipid carrier is a liquid at 37° C.
Claim 12
Dependent Claim 37 words
The lipid osmotic pump of claim 1, wherein said lipid carrier is selected from the group consisting of triglycerides, cocoa butter, hard butter, mineral oil, petrolatum-mineral oil mixtures, saqualine, fluorocarbons, fatty acids, their esters and mixtures thereof.
Claim 13
Dependent Claim 19 words
The lipid osmotic pump of claim 1, wherein said water insoluble wall further comprises plasticizer and flux regulating additives.
Claim 14
Dependent Claim 25 words
The lipid osmotic pump of claim 10, wherein 5 to 100 parts of plasticizer and flux regulating additives, per 100 parts wall polymer, are used.
Claim 15
Dependent Claim 37 words
The lipid osmotic pump of claim 1, wherein said polymer used to prepare said water insoluble wall is selected from the group consisting of cellulose acetate, cellulose diacetate, cellulose triacetate, cellulose acetate propionate, and cellulose acetate butyrate.
Claim 16
Dependent Claim 20 words
The lipid osmotic pump of claim 1, wherein said water insoluble wall has a thickness of 50 to 300 microns.
Claim 17
Dependent Claim 22 words
The lipid osmotic pump of claim 1, wherein said active agent is 1 μg to 5 g of at least one drug.
Claim 18
Dependent Claim 19 words
The lipid osmotic pump of claim 1, wherein 5 mg to 5 g of said lipid carrier is used.
Claim 19
Dependent Claim 17 words
The lipid osmotic pump of claim 1, wherein said osmotic agent is a water soluble active agent.
Claim 20
Dependent Claim 13 words
A water soluble capsule containing at least two osmotic pumps of claim 1.
Claim 21
Dependent Claim 14 words
The lipid osmotic pump of claim 1, wherein said core is a single compartment.
Claim 22
Dependent Claim 21 words
The lipid osmotic pump of claim 1, wherein in operation said osmotic agent is expelled, substantially subsequent to said lipid carrier.

References Cited (Backward Citations)

US3854480A Cited
US3948254A Cited
US3995632A Cited
US4111202A Cited
EP0010876A1 Cited
US4350271A Cited
US4522625A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-08-10 1991-02-09 1991-08-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-08-10 1995-02-09 1995-08-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-08-10 1999-02-09 1999-08-11 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag