Osmotic delivery system with early zero order push power engine

Abstract

The present invention is directed to an osmotic engine useful in an osmotic delivery system for delivery of a beneficial agent in a controlled manner over a preselected administration period. By including a flowable engine comprising at least one osmotic agent and at least one fluid vehicle, the resulting osmotic engine reaches a zero order push power or push rate quickly and provides steady delivery of the beneficial agent.

1 . An osmotic engine useful in an osmotic device for delivering a beneficial agent formulation, comprising a viscous, fluid suspension vehicle with limited osmotic power; the vehicle having at least one osmotic agent homogeneously dispersed within the vehicle to form a flowable composition that increases in size upon imbibing fluid from a fluid environment through a semipermeable membrane in the osmotic device.  
   
   
       2 . The osmotic engine of  claim 1 , wherein the vehicle has low infiltration activity in the semipermeable membrane.  
   
   
       3 . The osmotic engine of  claim 1 , wherein the vehicle is polysorbate or soybean oil.  
   
   
       4 . The osmotic engine of  claim 1 , wherein the at least one osmotic agent is sodium chloride.  
   
   
       5 . The osmotic engine of  claim 1 , further comprising a thickening agent.  
   
   
       6 . The osmotic engine of  claim 5 , wherein the thickening agent is a polymer.  
   
   
       7 . The osmotic engine of  claim 6 , wherein the polymer is present as 1 to 2% W/W.  
   
   
       8 . An osmotic device for delivering a beneficial agent formulation, comprising: 
 a wall comprising a semipermeable membrane;    a reservoir to store the beneficial agent formulation, the reservoir located inside the wall and having a passageway connecting the fluid environment with an interior of the reservoir; and    a viscous, fluid suspension vehicle with limited osmotic power, the vehicle having at least one osmotic agent homogeneously dispersed within the vehicle to form a flowable composition, the suspension vehicle located inside the wall and in contact with the semipermeable membrane.    
   
   
       9 . The osmotic device of  claim 8 , wherein the suspension vehicle has low infiltration activity in the semipermeable membrane.  
   
   
       10 . The osmotic device of  claim 8 , wherein the suspension vehicle is polysorbate or soybean oil.  
   
   
       11 . The osmotic device of  claim 8 , wherein the at least one osmotic agent is sodium chloride.  
   
   
       12 . The osmotic device of  claim 8 , wherein the suspension vehicle further comprises a thickening agent.  
   
   
       13 . The osmotic device of  claim 12 , wherein the thickening agent is a polymer.  
   
   
       14 . A method of making an osmotic device having an osmotic engine, comprising: 
 providing a wall comprising a semipermeable membrane;    providing a reservoir to store a beneficial agent formulation, the reservoir located inside the wall;    providing at least one osmotic agent;    providing a viscous, fluid suspension vehicle with limited osmotic power;    mixing the osmotic agent with the suspension vehicle to form a flowable osmotic composition that increases in size upon imbibing fluid from a fluid environment; and    placing the flowable osmotic composition into the osmotic device.    
   
   
       15 . The method of  claim 14 , wherein providing the suspension vehicle comprises providing a vehicle having a low infiltration activity in the semipermeable membrane.  
   
   
       16 . The method of  claim 14 , wherein providing the suspension vehicle comprises providing polysorbate or soybean oil.  
   
   
       17 . The method of  claim 14 , wherein providing at least one osmotic agent comprises providing sodium chloride.  
   
   
       18 . The method of  claim 14 , further comprising mixing a thickening agent into the flowable osmotic composition.  
   
   
       19 . The method of  claim 18 , wherein the thickening agent is a polymer.