Dosage forms having a barrier layer to laser ablation

Abstract

A dosage form includes an outer wall defining an interior compartment, a therapeutic agent within the interior compartment, at least one laser formed exit orifice in the outer wall, a barrier layer disposed between the outer wall and the interior compartment in at least a region corresponding to the at least one exit orifice, wherein the barrier layer comprises a material that allows the barrier layer to remain intact during formation of the at least one laser formed exit orifice, and an osmotic agent located within the wall.

1 . A dosage form comprising: 
 (a) an outer wall defining an interior compartment;    (b) a therapeutic agent within the interior compartment;    (c) at least one laser formed exit orifice in the outer wall;    (d) a barrier layer disposed between the outer wall and the interior compartment in at least a region corresponding to the at least one exit orifice, wherein the barrier layer comprises a material that allows the barrier layer to remain intact during formation of the at least one laser formed exit orifice; and    (e) an osmotic agent located within the outer wall.    
   
   
       2 . The dosage form of  claim 1 , wherein the osmotic agent is located in the interior compartment.  
   
   
       3 . The dosage form of  claim 1 , wherein the osmotic agent surrounds the interior compartment and underlies the outer wall.  
   
   
       4 . The dosage form of  claim 1 , wherein the outer wall comprises a semipermeable material.  
   
   
       5 . The dosage form of  claim 1 , wherein the barrier layer surrounds the interior compartment.  
   
   
       6 . The dosage form of  claim 1 , wherein the barrier layer is a contiguous film.  
   
   
       7 . The dosage form of  claim 1 , wherein the barrier layer is a non-contiguous porous film.  
   
   
       8 . The dosage form of  claim 1 , wherein the interior compartment contains the therapeutic agent in a solid state.  
   
   
       9 . The dosage form of  claim 1 , wherein the material is present in the barrier layer in an amount sufficient to make the barrier layer substantially impervious to laser ablation under a selected laser type and selected laser operating conditions used to form the exit orifice.  
   
   
       10 . The dosage form of  claim 9 , wherein the material is capable of reflecting laser energy from the selected laser type under the selected laser operating conditions used to form the at least one laser formed exit orifice.  
   
   
       11 . The dosage form of  claim 9 , wherein the material is capable of transmitting laser energy from a selected laser type and selected laser operating conditions used to form the at least one laser formed exit orifice.  
   
   
       12 . The dosage form of  claim 10 , wherein the selected laser is a carbon dioxide laser and the material is selected from the group consisting of carbon black, powdered stainless steel, powdered nickel, powdered iron, hydrous magnesium silicate (talc), powdered glass, titanium dioxide, magnesium aluminum silicate, aluminum silicate, aluminum oxide and metallic chips or flakes.  
   
   
       13 . A method for controlling depth of laser ablation on a surface of a dosage form during formation of at least one laser formed exit orifice in an outer wall defining an interior compartment containing a therapeutic agent comprising: 
 including in the dosage form, a barrier layer disposed between the outer wall and the interior compartment in at least a region corresponding to the at least one laser formed exit orifice, wherein the barrier layer comprises a material that is substantially impervious to laser ablation from a selected laser type and selected laser operating conditions used to form the at least one laser formed exit orifice.    
   
   
       14 . The method of  claim 13 , wherein the barrier layer comprises a material capable of reflecting laser energy from the selected laser type and selected laser operating conditions used to form the at least one laser formed exit orifice.  
   
   
       15 . The method of  claim 14 , wherein the selected laser is a carbon dioxide laser and the material comprising the barrier layer is selected from the group consisting of carbon black, powdered stainless steel, powdered nickel, powdered iron, hydrous magnesium silicate (talc), powdered glass, titanium dioxide, magnesium aluminum silicate, aluminum silicate, aluminum oxide and metallic chips or flakes.  
   
   
       16 . The method of  claim 13 , wherein the barrier layer is comprises a material capable of transmitting laser energy from the selected laser type and selected laser operating conditions used to form the at least one laser formed exit orifice.  
   
   
       17 . A method for controlling depth of at least one laser formed exit orifice in an outer polymer wall of a dosage form from a selected laser type at selected laser operating conditions, wherein the dosage form comprises an outer polymer wall defining an interior compartment comprising a therapeutic agent and having a barrier layer disposed between the outer polymer wall and the interior compartment comprising: 
 selecting a material for formation of the outer wall that is ablated by the selected laser type and the selected laser operating conditions; and    selecting a material for formation of the barrier layer that is substantially impervious to ablation by the selected laser type and selected laser operating conditions.