Combined diffusion/osmotic pumping drug delivery system
First Claim
1. A device for the controlled delivery of active agents to an environment of use, wherein the device comprises:
- a) a core located approximately at the center of the device and comprising at least one expandable hydrophilic polymer and, optionally, an osmagent, said core being able to absorb fluids from the environment of use;
b) a composition immediately surrounding the core comprising at least one active substance and, optionally, one or more of an osmagent and an osmopolymer;
c) a membrane immediately surrounding the composition and comprising a mixture of a cellulose acylate, a poly(methacrylate) copolymer salt and a plasticizer, wherein the membrane permits delivery of the at least one active substance through a combination of diffusion and osmotic pumping; and
d) one or more preformed passageways and plural micropores in the membrane that communicate the composition with the outside of the device.
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Accused Products
Abstract
Delivery devices capable of delivering one or more active substances by diffusion through plural micropores in the membrane or by osmotic pumping through one or more preformed passageways in the membrane are provided. The device has an about centrally located expandable core completely surrounded by an active substance-containing layer, which is completely surrounded by the membrane. The device is capable of delivering insoluble, slightly soluble, sparingly soluble and very soluble active substances to an environment of use. The preferred delivery rate is zero order. The device can deliver an active substance for a period of about 12-24 hours.
195 Citations
37 Claims
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1. A device for the controlled delivery of active agents to an environment of use, wherein the device comprises:
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a) a core located approximately at the center of the device and comprising at least one expandable hydrophilic polymer and, optionally, an osmagent, said core being able to absorb fluids from the environment of use;
b) a composition immediately surrounding the core comprising at least one active substance and, optionally, one or more of an osmagent and an osmopolymer;
c) a membrane immediately surrounding the composition and comprising a mixture of a cellulose acylate, a poly(methacrylate) copolymer salt and a plasticizer, wherein the membrane permits delivery of the at least one active substance through a combination of diffusion and osmotic pumping; and
d) one or more preformed passageways and plural micropores in the membrane that communicate the composition with the outside of the device. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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14. A device for the controlled delivery of an active substance to an environment of use wherein the active substance is one of very soluble, sparingly soluble, slightly soluble or insoluble in a fluid imbibed by the device from the environment of use, the device comprising:
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a core expandable in a fluid from the environment of use, the core being approximately centrally located in the device;
a layer comprising the active substance in contact with and surrounding the core; and
a membrane in contact with and surrounding the layer and comprising at least one passageway made by mechanical means for delivery of the active substance by osmotic pumping and plural micropores for delivery of the active substance by diffusion, wherein the membrane comprises about 1 to 99 weight percent of one or more cellulose esters, about 84 to 0.5 weight percent of one or more poly(methacrylate) copolymer salt and about 15 to 0.5 weight percent of one or more plasticizers. - View Dependent Claims (15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37)
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Specification