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Patent US4927687A successfully refreshed from Google Patents.
US4927687A
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Sustained release transdermal drug delivery composition
Assignee: Biotek Inc
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Filing: 1986-09-22
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Granted: 1990-05-22
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Expires: 2006-09-22
Abstract
Abstract A transdermal drug delivery system useful for the controlled, for example zero order release of one or more drugs to a selected skin area of a user, which system comprises an impervious backing sheet and a face membrane, the backing sheet and membrane secured together to form an intermediate reservoir. The face membrane is a macroporous membrane which has pores of sufficient size to avoid any rate control of the drug to be transdermally delivered to the user. The reservoir contains a viscous liquid base material selected to exude from the membrane to form a film and to occlude the skin of the user to force hydration of the stratum corneum with water from the lower layers of the epidermis of the user and a plurality of solid microparticles generally uniformly dispersed and suspended in the liquid base material. The microparticles containing an effective therapeutic amount of the drug for transdermal delivery, such as the contraceptive steroid. In use the liquid base material exuded from the macroporous membrane face forms a thermodynamically stable thin film layer in an intimate contact with the skin, while the drug is released from the microparticles into the base material and transdermally into the user.
Inventors
- 👤 Elie S. Nuwayser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:51
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/70; A61K9/7023; A61K9/703; A61K9/7084; Y; Y10; Y10S; Y10S516/00; Y10S516/922
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
214 words
A composition for the accelerated sustained release, transdermal delivery of a drug to a user, which composition comprises: (a) a viscous, film-forming base material selected to match generally the degree of hydrophobicity of the drug and, when placed in contact with the skin of the user, to occlude the skin of the user and to force hydration of the stratum corneum layer by diffusion of water from the lower layers of the epidermis of the user in use and to increase the porosity of the stratum corneum layer and thereby to accelerate the transdermal drug delivery across said layer; and (b) a plurality of drug rate controlling solid microparticles generally uniformly dispersed and suspended in the base material, the microparticles having a particle size of less than 1000 microns and containing an effective therapeutic amount of a drug for transdermal delivery, the active drug of transdermal delivery and the base material selected to permit the transport of the drug from the rate controlling microparticles and through the base material and into the skin of the user; whereby, on application to the skin of the user of the transdermal drug composition, the drug is released at a sustained release rate from the suspended microparticles into the base material and into the skin of the user.
Claim 2
Dependent Claim
214 words
A composition for the accelerated sustained release, transdermal delivery of a drug to a user, which composition comprises: (a) a viscous, film-forming base material selected to match generally the degree of hydrophobicity of the drug and, when placed in contact with the skin of the user, to occlude the skin of the user and to force hydration of the stratum corneum layer by diffusion of water from the lower layers of the epidermis of the user in use and to increase the porosity of the stratum corneum layer and thereby to accelerate the transdermal drug delivery across said layer; and (b) a plurality of drug rate controlling solid microparticles generally uniformly dispersed and suspended in the base material, the microparticles having a particle size of less than 1000 microns and containing an effective therapeutic amount of a drug for transdermal delivery, the active drug of transdermal delivery and the base material selected to permit the transport of the drug from the rate controlling microparticles and through the base material and into the skin of the user; whereby, on application to the skin of the user of the transdermal drug composition, the drug is released at a sustained release rate from the suspended microparticles into the base material and into the skin of the user.
Claim 3
Dependent Claim
20 words
The composition of claim 1 wherein the base material comprises a viscous hydrocarbon, and the drug comprises a water-insoluble drug.
Claim 4
Dependent Claim
21 words
The composition of claim 1 wherein the base material comprises a viscous hydrocarbon, and the drug comprises a hydrocarbon-soluble contraceptive steroid.
Claim 5
Dependent Claim
29 words
The composition of claim 1 wherein the microparticles comprise a biodegradable polymer admixed with the drug, and the microparticles contain a thin outer coating layer of a biodegradable polymer.
Claim 6
Dependent Claim
27 words
The composition of claim 1 wherein the base material comprises a glycerol water-containing base material, and wherein the drug to be transdermally delivered comprises a water-soluble drug.
Claim 7
Dependent Claim
17 words
The composition of claim 1 wherein the drug comprises: norethindrone, norgestrel, estradiol, levonorgestrel, mestranol, and combinations thereof.
Claim 8
Dependent Claim
24 words
The composition of claim 1 wherein the base material comprises a viscous hydrocarbon material having a melting point of 38° C. to 60° C.
Claim 9
Dependent Claim
57 words
The composition of claim 1 wherein the microparticle comprises a microparticle having a particle size of about 200 microns of less, wherein the active ingredient comprises a levonorgestrel or estradiol, wherein the active drug is admixed with a lactide or glycolide polymer, and wherein the microparticle has a wall thickness composed of a lactide or glycolide polymer.
Claim 10
Dependent Claim
21 words
The composition of claim 1 wherein the microparticles comprise from about 5 to 75 percent by weight of the base material.
Claim 11
Dependent Claim
24 words
The composition of claim 6 wherein the sustained release rate comprise a zero order release rate at about 5 to 150 micrograms per day.
Claim 12
Dependent Claim
20 words
The composition of claim 1 wherein the drug comprises from about 0.1 to 30 percent by weight of the microparticle.
Claim 13
Dependent Claim
20 words
The composition of claim 1 wherein the microparticles have a uniform outer wall coating of about 0.2 to 20 microns.
Claim 14
Dependent Claim
19 words
The composition of claim 1 wherein the concentration of the drug in the base material is close to saturation.
Claim 15
Dependent Claim
32 words
The composition of claim 1 wherein the microparticles comprise an admixture of the drug and a polymer to form an inner core and the microparticle include a thin outer polymer coating layer.
Claim 16
Dependent Claim
29 words
The composition of claim 14 wherein the outer polymer coating layer comprises a polymer which is the same or essentially the same as the polymer admixed with the drug.
Claim 17
Dependent Claim
215 words
A composition for the accelerated transdermal sustained release delivery of a drug to a user, which composition comprises: (a) a viscous, film-forming, hydrocarbon base material having a melting point of 38° C. to 60° C. selected when placed in contact with the skin of the user, to occlude the skin of the user and to force hydration of the stratum corneum layer with water from the lower layers of the epidermis of the user in use and thereby to accelerate drug delivery; and (b) a plurality of drug rate controlling solid microparticles generally uniformly dispersed and suspended in the base material and the containing an effective therapeutic amount of a steroid drug for transdermal delivery, the active drug material for transdermal delivery and the base material selected to permit the transport of the drug through the walls of the microparticles and the base material and into the skin of the user, and wherein the microparticles comprise a biodegradable polymer admixed with the drug, and the microparticles contain a thin outer coating layer of a biodegradable polymer; whereby, on application to the skin of the user of the transdermal drug composition, the drug is released at a accelerated, sustained release rate from the suspended microparticles into the base material and into the skin of the user.
Claim 18
Dependent Claim
215 words
A composition for the accelerated transdermal sustained release delivery of a drug to a user, which composition comprises: (a) a viscous, film-forming, hydrocarbon base material having a melting point of 38° C. to 60° C. selected when placed in contact with the skin of the user, to occlude the skin of the user and to force hydration of the stratum corneum layer with water from the lower layers of the epidermis of the user in use and thereby to accelerate drug delivery; and (b) a plurality of drug rate controlling solid microparticles generally uniformly dispersed and suspended in the base material and the containing an effective therapeutic amount of a steroid drug for transdermal delivery, the active drug material for transdermal delivery and the base material selected to permit the transport of the drug through the walls of the microparticles and the base material and into the skin of the user, and wherein the microparticles comprise a biodegradable polymer admixed with the drug, and the microparticles contain a thin outer coating layer of a biodegradable polymer; whereby, on application to the skin of the user of the transdermal drug composition, the drug is released at a accelerated, sustained release rate from the suspended microparticles into the base material and into the skin of the user.
Claim 19
Dependent Claim
17 words
The composition of claim 16 wherein the microparticles have a particle size of 200 microns or less.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-05-21 | 1993-11-20 | 1994-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-21 | 1997-11-20 | 1998-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-21 | 2001-11-20 | 2002-05-22 | $7700.00 | Window Closed / Lapsed |