Patent US3929132A successfully refreshed from Google Patents.
US3929132A
Expired / Lapsed
US
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Osmotic dispenser
Assignee: Alza Corp
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Filing: 1974-07-23
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Granted: 1975-12-30
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Expires: 1994-07-23
Abstract
Abstract An osmotic dispenser is described which is capable of releasing to its outside environment concentrations of active agent at an osmotically controlled rate over a prolonged period of time, and the active agent content of which dispenser is formulated in a form other than wholly in solution, namely, the active agent is formulated as a dispersion, suspension, emulsion, cream, gel, paste, slurry, or the like, and most preferably all of the above are characterized by the consistency of either the semisolid or solid state.
Inventors
- 👤 Takeru Higuchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:53
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/0002; A61K9/0004
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
195 words
An osmotic active agent dispenser comprised of a first compartment of relatively impervious material containing an active agent and provided with means for releasing the active agent to the exterior of the dispenser, and a second compartment of controlled permeability to water containing a solution of an osmotically effective solute which exhibits an osmotic pressure gradient against water, the said first and second compartments having a barrier member such that the said first compartment diminishes in volume in response to an increase in volume of the solution in the said second compartment via absorption of water by osmosis therein and defining a means for establishing a substantially zero order rate of release as water flows into the dispenser in a tendency towards osmotic equilibrium with its environment, so that the active agent is continuously squeezed thereout at an osmotically controlled rate over a prolonged period of time; said active agent being formulated in a form other than wholly in liquid solution, and characterized by a consistency at least as firm as that of the semisolid state, whereby the uniformity of dosage of the said active agent over the said prolonged period of time is assured.
Claim 2
Dependent Claim
195 words
An osmotic active agent dispenser comprised of a first compartment of relatively impervious material containing an active agent and provided with means for releasing the active agent to the exterior of the dispenser, and a second compartment of controlled permeability to water containing a solution of an osmotically effective solute which exhibits an osmotic pressure gradient against water, the said first and second compartments having a barrier member such that the said first compartment diminishes in volume in response to an increase in volume of the solution in the said second compartment via absorption of water by osmosis therein and defining a means for establishing a substantially zero order rate of release as water flows into the dispenser in a tendency towards osmotic equilibrium with its environment, so that the active agent is continuously squeezed thereout at an osmotically controlled rate over a prolonged period of time; said active agent being formulated in a form other than wholly in liquid solution, and characterized by a consistency at least as firm as that of the semisolid state, whereby the uniformity of dosage of the said active agent over the said prolonged period of time is assured.
Claim 3
Dependent Claim
16 words
The osmotic dispenser as defined in claim 1, wherein the active agent formulation is a semisolid.
Claim 4
Dependent Claim
16 words
The osmotic dispenser as defined in claim 1, wherein the active agent formulation is a solid.
Claim 5
Dependent Claim
27 words
The osmotic dispenser as defined by claim 1, wherein the active agent formulation is a thickened liquid having a viscosity of at least 1,000 centipoises at 20*C.
Claim 6
Dependent Claim
18 words
The osmotic dispenser as defined in claim 1, wherein the active agent formulation further comprises a nonionic surfactant.
Claim 7
Dependent Claim
30 words
The osmotic dispenser as defined in claim 5, wherein the surfactant is selected from the group consisting of sorbitan mono-stearate, sorbitan monooleate, polyoxyethylene (20) sorbitan monooleate, and polyoxyethylene 40 stearate.
Claim 8
Dependent Claim
17 words
The osmotic dispenser as defined in claim 1, wherein the active agent formulation further comprises an anti-oxidant.
Claim 9
Dependent Claim
27 words
The osmotic dispenser as defined in claim 7, wherein the anti-oxidant is selected from the group consisting of 2,6-ditertiary-butyl-p-cresol, propyl gallate, tertiary butyl-4-methoxyphenol, ethoxyquin and nordihydroguaiaretic acid.
Claim 10
Dependent Claim
20 words
The osmotic dispenser as defined by claim 1, wherein the active agent formulation further comprises an inert particulate solid filler.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-29 | 1979-06-30 | 1979-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-29 | 1983-06-30 | 1983-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-29 | 1987-06-30 | 1987-12-30 | $7700.00 | Window Closed / Lapsed |