Osmotic delivery systems and piston assemblies for use therein
First Claim
1. An osmotic delivery system for delivering an active agent formulation to a fluid environment, comprising:
- a reservoir comprising an inner wall and a lumen, wherein the lumen contains the active agent formulation and an osmotic agent formulation; and
a piston assembly positioned in the lumen to isolate the active agent formulation from the osmotic agent formulation, the piston assembly comprising a columnar body and one or more O-rings, wherein (i) the columnar body has a core made of a first material that is an incompressible material, the columnar body further comprising one or more concentric grooves, wherein the incompressible material is selected from the group consisting of an ultra high molecular weight polyethylene and a polyaryletherketone, and the incompressible material produces volatile leachates of less than 1.4 μ
g/mL when exposed to benzyl benzoate at 40°
C. for at least 45 days, and (ii) each groove retains one of the one or more O-rings and each of the one or more O-rings are made of a second material that is an elastomeric material, wherein each O-ring engages and maintains a seal against the inner wall of the reservoir.
7 Assignments
0 Petitions
Accused Products
Abstract
An osmotic delivery system is disclosed for delivering an active agent formulation to a fluid environment. The osmotic delivery system typically comprises a reservoir having a lumen that contains the active agent formulation and an osmotic agent formulation and a piston assembly positioned in the lumen to isolate the active agent formulation from the osmotic agent formulation. The piston assembly typically comprises a body constructed and arranged for positioning in the lumen. The body is typically made of a polymeric material that is, for example, resistant to leaching in an organic solvent. In one embodiment, the body is a columnar body having a rim at a distal end thereof for engaging and sealing against a wall of the reservoir and the piston assembly further comprises a spring retained at the distal end of the columnar body for biasing the rim of the columnar body against the wall of the reservoir.
-
Citations
19 Claims
-
1. An osmotic delivery system for delivering an active agent formulation to a fluid environment, comprising:
-
a reservoir comprising an inner wall and a lumen, wherein the lumen contains the active agent formulation and an osmotic agent formulation; and a piston assembly positioned in the lumen to isolate the active agent formulation from the osmotic agent formulation, the piston assembly comprising a columnar body and one or more O-rings, wherein (i) the columnar body has a core made of a first material that is an incompressible material, the columnar body further comprising one or more concentric grooves, wherein the incompressible material is selected from the group consisting of an ultra high molecular weight polyethylene and a polyaryletherketone, and the incompressible material produces volatile leachates of less than 1.4 μ
g/mL when exposed to benzyl benzoate at 40°
C. for at least 45 days, and (ii) each groove retains one of the one or more O-rings and each of the one or more O-rings are made of a second material that is an elastomeric material, wherein each O-ring engages and maintains a seal against the inner wall of the reservoir. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
16. An osmotic delivery system for delivering an active agent formulation to a fluid environment, comprising:
-
a reservoir comprising an inner wall and a lumen, wherein the lumen contains the active agent formulation and an osmotic agent formulation; and a piston assembly positioned in the lumen to isolate the active agent formulation from the osmotic agent formulation, the piston assembly comprising a columnar body and one or more O-rings, wherein (i) the columnar body has a core made of a first material that is an incompressible material, the columnar body further comprising one or more concentric grooves, wherein the incompressible material is an ultra high molecular weight polyethylene, and (ii) each groove retains one of the one or more O-rings and each of the one or more O-rings are made of a second material that is an elastomeric material, wherein each O-ring engages and maintains a seal against the inner wall of the reservoir. - View Dependent Claims (17, 18, 19)
-
Specification