Sustained delivery of leuprolide using an implantable system
AssigneeAlza Corporation
InventorsJohn R. Peery, Keith E. Dionne, James B. Eckenhoff, Felix A. Landrau, Scott D. Lautenbach, Judy A. Magruder, Jeremy C. Wright
Life of this patent
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Abstract
The invention is directed to a device for delivering an active agent formulation for a predetermined administration period. An impermeable reservoir is divided into a water-swellable agent chamber and an active agent formulation chamber. Fluid from the environment is imbibed through a semipermeable plug into the water-swellable agent chamber and the active agent formulation is released through a back-diffusion regulating outlet. Delivery periods of up to 2 years are achieved.
Claims17
An implantable leuprolide delivery system comprising:
- (a) an impermeable reservoir;
- (b) a piston that divides the reservoir into a first and a second chamber, the first and second chambers each having an open end;
- (c) a water-swellable agent formulation in the first chamber;
- (d) a leuprolide formulation in the second chamber;
- (e) a semipermeable plug in the open end of the first chamber;
- and
- (f) a back-diffusion regulating outlet in the open end of the second chamber;
- wherein the system effectively seals the second chamber and isolates the leuprolide formulation from the environment of use.
An implantable leuprolide delivery system comprising:
- (a) a titanium alloy reservoir;
- (b) a styrene-ethylene-butylene-styrene copolymer piston that divides the reservoirs into a first and a second chamber, the first and second chambers each having an open end;
- (c) a compressed NaCl-based osmotic engine and a PEG additive in the first chamber;
- (d) 65 mg leuprolide as a leuprolide acetate solution in DMSO in the second chamber;
- (e) a semipermeable polyurethane plug with 20% water uptake in the open end of the first chamber;
- and
- (f) a polyethylene back diffusion regulating outlet with a helical flow path in the open end of the second chamber;
- wherein the system continuously delivers about 150 .mu.g leuprolide per day for about one year after subcutaneous implantation.
Dependencies are inferred from the claim text.