Dual rate agent delivery device

Claim 1

A delivery device for dispensing a beneficial agent to an environment of use at two different rates and having a faster startup, where the device comprises: a) a housing comprised of a wall surrounding an internal compartment, the wall being semipermeable in at least a portion; b) a first beneficial agent formulation, comprising a first beneficial agent and a pharmaceutically acceptable hydrophilic carrier, in the compartment; c) a second beneficial agent formulation, comprising a second beneficial agent and a pharmaceutically acceptable hydrophilic carrier, in the compartment; d) a first exit means within that portion of the wall of the housing in contact with the first beneficial agent formulation, the exit means comprising an exit passageway or a multiplicity of exit passageways, the diameter of each passageway being of a size to provide rapid and continued delivery of the first beneficial agent for a first time period; e) a second exit means in the compartment between the first beneficial agent formulation and the second beneficial agent formulation, the second exit means comprising an exit partition layer having an exit passageway or a multiplicity of exit passageways, the diameter of each passageway being of a size for maximizing the release of the second beneficial agent by osmotic pumping and minimizing the release of the beneficial agent by diffusion or erosion to provide continuous and sustained delivery in a controlled and uniform manner over a prolonged period of time; and f) an expandable driving member in the compartment.

Claim 11

A method for dispensing a beneficial agent to an environment of use at two different rates and having a faster startup, the method comprising the steps of: (1) admitting into the environment of use a dispenser comprising: a) a housing comprised of a wall surrounding an internal compartment, the wall being semipermeable in at least a portion; b) a first beneficial agent formulation, comprising a first beneficial agent and a pharmaceutically acceptable hydrophilic carrier, in the compartment; c) a second beneficial agent formulation, comprising a second beneficial agent and a pharmaceutically acceptable hydrophilic carrier, in the compartment; d) a first exit means within that portion of the wall of the housing in contact with the first beneficial agent formulation, the exit means comprising an exit passageway or a multiplicity of exit passageways, the diameter of each passageway being of a size to provide rapid and continued delivery of the first beneficial agent for a first time period; e) a second exit means in the compartment between the first beneficial agent formulation and the second beneficial agent formulation, the second exit means comprising an exit partition layer having an exit passageway or a multiplicity of exit passageways, the diameter of each passageway being of a size for maximizing the release of the second beneficial agent by osmotic pumping and minimizing the release of the beneficial agent by diffusion or erosion to provide continuous and sustained delivery in a controlled and uniform manner over a prolonged period of time; and f) an expandable driving member in the compartment; (2) imbibing fluid through the semipermeable wall at a rate determined by the permeability of the wall and the osmotic pressure gradient across the wall, which fluid contacts the formulation comprising the beneficial agent to form a dispensable composition and contacts the expandable driving member to cause the expandable driving member to expand and push against the agent composition; (3) quickly delivering the first beneficial agent from the compartment by the first beneficial agent formulation being dispensed in a beneficially effective amount through the first exit means by diffusion or erosion into the environment of use for a first period of time; and (4) delivering the second beneficial agent from the compartment by the expandable driving member continually expanding against the second beneficial agent formulation and causing the beneficial agent to be dispensed in a beneficially effective amount through the second exit means at a controlled rate to the environment of use over a prolonged period of time

Claim 12

A method for dispensing a beneficial agent to an environment of use at two different rates and having a faster startup, the method comprising the steps of: (1) admitting into the environment of use a dispenser comprising: a) a housing comprised of a wall surrounding an internal compartment, the wall being semipermeable in at least a portion; b) a first beneficial agent formulation, comprising a first beneficial agent and a pharmaceutically acceptable hydrophilic carrier, in the compartment; c) a second beneficial agent formulation, comprising a second beneficial agent and a pharmaceutically acceptable hydrophilic carrier, in the compartment; d) a first exit means within that portion of the wall of the housing in contact with the first beneficial agent formulation, the exit means comprising an exit passageway or a multiplicity of exit passageways, the diameter of each passageway being of a size to provide rapid and continued delivery of the first beneficial agent for a first time period; e) a second exit means in the compartment between the first beneficial agent formulation and the second beneficial agent formulation, the second exit means comprising an exit partition layer having an exit passageway or a multiplicity of exit passageways, the diameter of each passageway being of a size for maximizing the release of the second beneficial agent by osmotic pumping and minimizing the release of the beneficial agent by diffusion or erosion to provide continuous and sustained delivery in a controlled and uniform manner over a prolonged period of time; and f) an expandable driving member in the compartment; (2) imbibing fluid through the semipermeable wall at a rate determined by the permeability of the wall and the osmotic pressure gradient across the wall, which fluid contacts the formulation comprising the beneficial agent to form a dispensable composition and contacts the expandable driving member to cause the expandable driving member to expand and push against the agent composition; (3) quickly delivering the first beneficial agent from the compartment by the first beneficial agent formulation being dispensed in a beneficially effective amount through the first exit means by diffusion or erosion into the environment of use for a first period of time; and (4) delivering the second beneficial agent from the compartment by the expandable driving member continually expanding against the second beneficial agent formulation and causing the beneficial agent to be dispensed in a beneficially effective amount through the second exit means at a controlled rate to the environment of use over a prolonged period of time