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US3977404A Expired / Lapsed US ⏱️ 0.0 years remaining

Osmotic device having microporous reservoir

Assignee: Alza Corp
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Filing: 1975-09-08
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Granted: 1976-08-31
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Expires: 1995-09-08
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Abstract

Abstract An osmotic device for delivering an active agent is disclosed. The device is comprised of a wall surrounding in at least a part, a reservoir containing agent. The wall is formed of a material permeable to an external fluid and impermeable to agent. The reservoir is formed of a microporous material permeable to agent and fluid, and having at least one micropore that is a passageway for release of agent. The agent is soluble in the fluid and exhibits an osmotic pressure gradient against the fluid, or the agent has limited solubility in the fluid and is admixed with an osmotically effective compound soluble in fluid that exhibits an osmotic pressure gradient against fluid. In operation, agent is released by fluid permeating through the wall into the reservoir producing a solution of agent or a solution of compound containing agent, which solution in either instance is released through the micropore to the exterior of the device.

Inventors

  • 👤 Felix Theeuwes

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-22 22:48
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/0002; A61K9/0004; A61F; A61F6/00; A61F6/06; A61F6/14; A61F6/142; A61F6/144; A61F9/00; A61F9/0008; A61F9/0017

Claims Analysis

Total Claims: 44
Claim 1
Independent Claim 217 words
An osmotic device for the continuous dispensing of an active agent to an environment of use, said device comprising: a. a shaped wall formed of a semipermeable material that maintains its integrity during the dispensing period and is characterized as permeable to the passage of an external fluid in the environment of use and substantially impermeable to the passage of the active agent with the wall surrounding in at least a part; b. a reservoir formed of a material having a plurality of micropores with the reservoir containing an active agent that is soluble in the external fluid and exhibits an osmotic pressure gradient across the wall against the fluid; c. a passageway for dispensing agent from the device, said passageway consisting of at least one micropore that communicates with the reservoir and the exterior of the device; and d. wherein in operation with the device in the environment of use, external fluid is continuously imbibed through the wall into the reservoir in a tendency towards osmotic equilibrium at a rate determined by the permeability of the wall and the osmotic pressure gradient across the wall, thereby continuously dissolving the agent which is dispensed from the reservoir through the microporous passageway to the exterior of the device at a controlled rate over a prolonged period of time.
Claim 2
Dependent Claim 217 words
An osmotic device for the continuous dispensing of an active agent to an environment of use, said device comprising: a. a shaped wall formed of a semipermeable material that maintains its integrity during the dispensing period and is characterized as permeable to the passage of an external fluid in the environment of use and substantially impermeable to the passage of the active agent with the wall surrounding in at least a part; b. a reservoir formed of a material having a plurality of micropores with the reservoir containing an active agent that is soluble in the external fluid and exhibits an osmotic pressure gradient across the wall against the fluid; c. a passageway for dispensing agent from the device, said passageway consisting of at least one micropore that communicates with the reservoir and the exterior of the device; and d. wherein in operation with the device in the environment of use, external fluid is continuously imbibed through the wall into the reservoir in a tendency towards osmotic equilibrium at a rate determined by the permeability of the wall and the osmotic pressure gradient across the wall, thereby continuously dissolving the agent which is dispensed from the reservoir through the microporous passageway to the exterior of the device at a controlled rate over a prolonged period of time.
Claim 3
Dependent Claim 25 words
The osmotic device according to claim 1 wherein the reservoir is formed of a microporous material having a reflection coefficient of from 0 to 0.5.
Claim 4
Dependent Claim 33 words
The osmotic device according to claim 1 wherein the reservoir is formed of a microporous material consisting of from 5 to 95% pores having a pore size of 10 angstroms to 100 microns.
Claim 5
Dependent Claim 61 words
The osmotic device according to claim 1 wherein the reservoir is formed of a microporous material consisting of pores with a radius of ##EQU7## wherein J is the volume flux, η is the viscosity of the liquid, ε is the porosity, ΔP is the pressure difference across the material, Δx is the thickness of the material and τ is the tortuosity.
Claim 6
Dependent Claim 68 words
The osmotic device according to claim 1 wherein the wall formed of a semipermeable material has a flux consisting of ##EQU8## wherein J is the volume of liquid transported across the wall, A is the area of the wall, h is the thickness of the wall, L P is the permeability coefficient, σ is the reflection coefficient, Δπ is the osmotic pressure and ΔP is the hydrostatic pressure.
Claim 7
Dependent Claim 44 words
The osmotic device according to claim 1 wherein the active agent is a member selected from the group consisting of levo-dopa, aspirin, salicylamide, ferrous lactate, ferrous fumurate, ferrous gluconate, potassium sulfate, potassium chloride, potassium fluoride, chlorathiazide, acetazolamide, methazolamide, ascorbic acid, benzodiazepines, tolbutamide and chlorpropamide.
Claim 8
Dependent Claim 33 words
The osmotic device for the continuous dispensing of an active agent according to claim 1 wherein the reservoir is substantially insoluble in the external fluid and maintains its integrity during the dispensing period.
Claim 9
Dependent Claim 52 words
The osmotic device for the continuous dispensing of an active agent according to claim 1 wherein the agent is a member selected from the group consisting of locally and systemically acting drugs and the device is sized and adapted as a dosage form for the administration of agent to the gastrointestinal tract.
Claim 10
Dependent Claim 38 words
The osmotic device for the continuous dispensing of an active agent according to claim 1 wherein the agent is mixed with an inorganic or organic osmotically effective compound that exhibits an osmotic pressure gradient against the external fluid.
Claim 11
Dependent Claim 30 words
The osmotic device for the continuous dispensing of an active agent according to claim 9 wherein the osmotically effective compound exhibits an osmotic pressure of from 0 to 500 atmospheres.
Claim 12
Dependent Claim 25 words
The osmotic device for the continuous dispensing of an active agent according to claim 1 wherein the device is shaped and adapted for vaginal use.
Claim 13
Dependent Claim 28 words
The osmotic device for the continuous dispensing of an active agent according to claim 1 wherein the devices is shaped, sized and adapted for placement in the uterus.
Claim 14
Dependent Claim 31 words
The osmotic device for the continuous dispensing of an active agent according to claim 12 wherein the agent is a member selected from the group consisting of progestational and estrogenic steroids.
Claim 15
Dependent Claim 28 words
The osmotic device for the continuous dispensing of an active agent according to claim 1 wherein the device is structured and adapted to be placed in the anus.
Claim 16
Dependent Claim 24 words
The osmotic device for the continuous dispensing of an agent according to claim 1 wherein the semipermeable wall is formed of an erodible material.
Claim 17
Dependent Claim 23 words
The osmotic device for the continuous dispensing of an agent according to claim 1 wherein the reservoir is formed of an erodible material.
Claim 18
Dependent Claim 205 words
An osmotic device for continuously dispensing an active agent to an environment of use, said device comprising: a. a shaped wall formed of a semipermeable material that is permeable to the passage of an external fluid and substantially impermeable to the passage of an active agent, said wall surrounding in part; b. a compartment formed of a microporous material and having at least one micropore that communicates with the compartment and the exterior of the device, said compartment containing an active agent having limited solubility in the external fluid and an osmotically effective compound which exhibits an osmotic pressure gradient across the wall against the fluid; c. a passageway for dispensing agent from the device, said passageway consisting of at least one micropore that communicates with the exterior of the device; and d. wherein in operation with the device in the environment of use, external fluid is imbibed through the wall into the compartment in a tendency towards osmotic equilibrium at a rate controlled by the permeability of the wall and the osmotic pressure gradient across the wall thereby continuously dissolving the compound, which as a mixture with the agent, is dispensed through the passageway at a controlled rate for a prolonged period of time.
Claim 19
Dependent Claim 205 words
An osmotic device for continuously dispensing an active agent to an environment of use, said device comprising: a. a shaped wall formed of a semipermeable material that is permeable to the passage of an external fluid and substantially impermeable to the passage of an active agent, said wall surrounding in part; b. a compartment formed of a microporous material and having at least one micropore that communicates with the compartment and the exterior of the device, said compartment containing an active agent having limited solubility in the external fluid and an osmotically effective compound which exhibits an osmotic pressure gradient across the wall against the fluid; c. a passageway for dispensing agent from the device, said passageway consisting of at least one micropore that communicates with the exterior of the device; and d. wherein in operation with the device in the environment of use, external fluid is imbibed through the wall into the compartment in a tendency towards osmotic equilibrium at a rate controlled by the permeability of the wall and the osmotic pressure gradient across the wall thereby continuously dissolving the compound, which as a mixture with the agent, is dispensed through the passageway at a controlled rate for a prolonged period of time.
Claim 20
Dependent Claim 18 words
The osmotic device for dispensing an active agent according to claim 17 wherein the agent is a drug.
Claim 21
Dependent Claim 27 words
The osmotic device for dispensing an active agent according to claim 17 wherein the osmotically effective compound exhibits an osmotic pressure of from 20 to 500 atmospheres.
Claim 22
Dependent Claim 30 words
The osmotic device for dispensing an active agent according to claim 17 wherein the active agent is a member selected from the group consisting of nutrient, vitamin and growth promoter.
Claim 23
Dependent Claim 29 words
The osmotic device for dispensing an active agent according to claim 17 wherein the agent is a member selected from the group consisting of biocide, insecticide, fungicide and algicide.
Claim 24
Dependent Claim 195 words
An osmotic device for the continuous dispensing of an active agent to an environment of use, said device comprising: a. a shaped wall formed of a material that is permeable to the passage of an external fluid in the environment of use and substantially impermeable to the passage of an active agent with the wall surrounding; b. a reservoir formed of a material having a plurality of micropores, said reservoir providing support for the wall and containing an active agent that is soluble in the external fluid and exhibits an osmotic pressure gradient across the wall against the fluid; c. a passageway for dispensing agent from the device, said passageway consisting of at least one micropore that communicates with the reservoir and the exterior of the device; and, d. wherein in operation with the device in the environment of use, external fluid is imbibed through the wall into the reservoir at a rate determined by the permeability of the wall and the osmotic pressure gradient across the wall, thereby dissolving the agent which is dispensed from the reservoir through the passageway to the exterior of the device at a controlled and continuous rate over time.
Claim 25
Dependent Claim 195 words
An osmotic device for the continuous dispensing of an active agent to an environment of use, said device comprising: a. a shaped wall formed of a material that is permeable to the passage of an external fluid in the environment of use and substantially impermeable to the passage of an active agent with the wall surrounding; b. a reservoir formed of a material having a plurality of micropores, said reservoir providing support for the wall and containing an active agent that is soluble in the external fluid and exhibits an osmotic pressure gradient across the wall against the fluid; c. a passageway for dispensing agent from the device, said passageway consisting of at least one micropore that communicates with the reservoir and the exterior of the device; and, d. wherein in operation with the device in the environment of use, external fluid is imbibed through the wall into the reservoir at a rate determined by the permeability of the wall and the osmotic pressure gradient across the wall, thereby dissolving the agent which is dispensed from the reservoir through the passageway to the exterior of the device at a controlled and continuous rate over time.
Claim 26
Dependent Claim 189 words
An ocular osmotic device for the continuous and prolonged administration of an ophthalmic drug, said device comprising: a. an ophthalmic drug that exhibits an osmotic pressure gradient against eye fluid; b. a shaped wall formed of a semipermeable material that maintains its integrity during the dispensing period and which material is permeable to the passage of eye fluid and substantially impermeable to the passage of drug, the wall surrounding in part; c. a reservoir formed of a microporous material with the reservoir containing the drug; d. a passageway for dispensing the drug from the device, said pasageway consisting of at least one micropore that communicates with the reservoir and the exterior of the device; and e. wherein in operation with the device in the environment of use, eye fluid is continuously imbibed through the wall into the reservoir in a tendency towards osmotic equilibrium at a rate determined by the permeability of the wall and the osmotic pressure gradient across the wall, thereby dissolving the drug which is dispensed from the reservoir through the microporous passageway to the environment at a controlled rate over a prolonged period of time.
Claim 27
Dependent Claim 189 words
An ocular osmotic device for the continuous and prolonged administration of an ophthalmic drug, said device comprising: a. an ophthalmic drug that exhibits an osmotic pressure gradient against eye fluid; b. a shaped wall formed of a semipermeable material that maintains its integrity during the dispensing period and which material is permeable to the passage of eye fluid and substantially impermeable to the passage of drug, the wall surrounding in part; c. a reservoir formed of a microporous material with the reservoir containing the drug; d. a passageway for dispensing the drug from the device, said pasageway consisting of at least one micropore that communicates with the reservoir and the exterior of the device; and e. wherein in operation with the device in the environment of use, eye fluid is continuously imbibed through the wall into the reservoir in a tendency towards osmotic equilibrium at a rate determined by the permeability of the wall and the osmotic pressure gradient across the wall, thereby dissolving the drug which is dispensed from the reservoir through the microporous passageway to the environment at a controlled rate over a prolonged period of time.
Claim 28
Dependent Claim 32 words
An ocular device for the dispensing of an ophthalmic drug according to claim 23 wherein the drug is a member selected from the group consisting of pilocarpine and its pharmaceutically acceptable salts.
Claim 29
Dependent Claim 35 words
An ocular device for the dispensing of an ophthalmic drug according to claim 23 wherein the ophthalmic drug is a member selected from the group consisting of epinephrine, ephedrine, norepinephrine, penicillin, tetracycline, oxytetracycline and chlorotetracycline.
Claim 30
Dependent Claim 199 words
An oral, osmotic device for the controlled and continuous dispensing of a unit dosage amount of drug to the gastrointestinal tract, said device comprising: a. a shaped wall formed of a semipermeable material that is permeable to the passage of an external gastrointestinal fluid and is substantially impermeable to drug, said wall having an opening and surrounding; b. a compartment formed of microporous material and containing a unit dosage amount of drug that is soluble in the fluid and exhibits an osmotic pressure gradient across the wall against the fluid when the device is in the environment of use; c. a passageway for dispensing the drug, said passageway consisting of at least one micropore that communicates with the opening in the wall and the exterior of the device; and d. wherein in operation with the device in the environment of use, external fluid is imbibed through the wall into the compartment in a tendency towards osmotic equilibrium at a rate controlled by the permeability of the wall and the osmotic pressure gradient across the wall producing a solution that is dispensed through the passageway from the device at a controlled and continuous rate over a prolonged period of time.
Claim 31
Dependent Claim 199 words
An oral, osmotic device for the controlled and continuous dispensing of a unit dosage amount of drug to the gastrointestinal tract, said device comprising: a. a shaped wall formed of a semipermeable material that is permeable to the passage of an external gastrointestinal fluid and is substantially impermeable to drug, said wall having an opening and surrounding; b. a compartment formed of microporous material and containing a unit dosage amount of drug that is soluble in the fluid and exhibits an osmotic pressure gradient across the wall against the fluid when the device is in the environment of use; c. a passageway for dispensing the drug, said passageway consisting of at least one micropore that communicates with the opening in the wall and the exterior of the device; and d. wherein in operation with the device in the environment of use, external fluid is imbibed through the wall into the compartment in a tendency towards osmotic equilibrium at a rate controlled by the permeability of the wall and the osmotic pressure gradient across the wall producing a solution that is dispensed through the passageway from the device at a controlled and continuous rate over a prolonged period of time.
Claim 32
Dependent Claim 39 words
The oral device according to claim 26 wherein the drug is mixed with a member selected from the group consisting of inorganic and organic osmotically effective compounds that exhibit an osmotic pressure gradient across the wall against the fluid.
Claim 33
Dependent Claim 35 words
The oral device according to claim 26 wherein the drug is a member selected from the group consisting of acetazolamide, potassium chloride, ascorbic acid, acetylsalicyclic acid, levo-dopa, methazolamide, scopolamine, ferrous fumurate, ferrous lactate and nitroglycerin.
Claim 34
Dependent Claim 29 words
The oral device according to claim 26 wherein the wall is formed of a member selected from the group consisting of cellulose acetate, cellulose triacetate and cellulose acetate butyrate.
Claim 35
Dependent Claim 30 words
The oral device according to claim 26 wherein the microporous material maintains its integrity in the environment of use and has an osmotic reflection coefficient of from 0 to 0.5.
Claim 36
Dependent Claim 32 words
The oral device according to claim 30 wherein the reflection coefficient is the hydrostatic pressure difference times the osmotic volume flux divided by the osmotic pressure difference times the hydrostatic volume flux.
Claim 37
Dependent Claim 25 words
The oral device according to claim 26 wherein the compartment contains a member selected from the group consisting of a dispersant, emulsifier and wetting agent.
Claim 38
Dependent Claim 16 words
The oral device according to claim 26 wherein the wall is formed of an erodible material.
Claim 39
Dependent Claim 17 words
The oral device according to claim 26 wherein the compartment is formed of an erodible microporous material.
Claim 40
Independent Claim 212 words
A method for continuously administering an active agent at a controlled rate to the gastrointestinal tract of a warm blooded animal comprising: A. admitting into the gastrointestinal tract an osmotic device shaped and sized for oral administration with the device comprising; 1. a wall formed of a pharmaceutically acceptable semipermeable material that is permeable to the passage of gastrointestinal fluid and substantially impermeable to the passage of an active agent, said wall having an opening and surrounding; 2. a compartment formed of a microporous material and containing a unit dosage amount of active agent that is soluble in the fluid and exhibits an osmotic pressure gradient across the wall against the fluid; 3. a passageway for dispensing the active agent, said passageway consisting of at least one micropore that communicates with the opening in the wall and the exterior of the device; B. dissolving said agent in the compartment in gastrointestinal fluid being imbibed through the wall into the compartment at a rate determined by the permeability of the wall and the osmotic pressure gradient across the wall to continuously dissolve the agent; and C. releasing the agent from the device at a therapeutically effective controlled and continuous rate through the passageway to the gastrointestinal tract over a prolonged period of time.
Claim 41
Independent Claim 212 words
A method for continuously administering an active agent at a controlled rate to the gastrointestinal tract of a warm blooded animal comprising: A. admitting into the gastrointestinal tract an osmotic device shaped and sized for oral administration with the device comprising; 1. a wall formed of a pharmaceutically acceptable semipermeable material that is permeable to the passage of gastrointestinal fluid and substantially impermeable to the passage of an active agent, said wall having an opening and surrounding; 2. a compartment formed of a microporous material and containing a unit dosage amount of active agent that is soluble in the fluid and exhibits an osmotic pressure gradient across the wall against the fluid; 3. a passageway for dispensing the active agent, said passageway consisting of at least one micropore that communicates with the opening in the wall and the exterior of the device; B. dissolving said agent in the compartment in gastrointestinal fluid being imbibed through the wall into the compartment at a rate determined by the permeability of the wall and the osmotic pressure gradient across the wall to continuously dissolve the agent; and C. releasing the agent from the device at a therapeutically effective controlled and continuous rate through the passageway to the gastrointestinal tract over a prolonged period of time.
Claim 42
Dependent Claim 24 words
A method according to claim 35 wherein the agent is a drug that produces a local or systemic effect on release from the device.
Claim 43
Dependent Claim 33 words
A method according to claim 35 wherein the agent is a powder and is mixed with an osmotically effective compound that exhibits an osmotic pressure gradient across the semipermeable wall against the fluid.
Claim 44
Dependent Claim 13 words
A method according to claim 35 wherein the microporous material is a solid.

References Cited (Backward Citations)

US3878977A Cited
US3765414A Cited
US3845770A Cited
US3851648A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-08-31 1980-03-01 1980-08-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-08-31 1984-03-01 1984-08-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-08-31 1988-03-01 1988-08-31 $7700.00 Window Closed / Lapsed

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