Engineered particles and methods of use

Abstract

Engineered particles are provided may be used for the delivery of a bioactive agent to the respiratory tract of a patient. The particles may be used in the form of dry powders or in the form of stabilized dispersions comprising a nonaqueous continuous phase. In particularly preferred embodiments the particles may be used in conjunction with an inhalation device such as a dry powder inhaler, metered dose inhaler or a nebulizer.

1 . (canceled)  
     
     
         2 . A composition comprising microspheres, wherein said microspheres have a wall thickness of 100 to 500 nm, and a bulk density of no more than 0.1 g/cm 3 .  
     
     
         3 . The composition according to  claim 2 , wherein the mean geometric particle size of said microspheres is less than 20 μm.  
     
     
         4 . A composition comprising microspheres, wherein said microspheres have a wall thickness of 43.5 to 261 nm.  
     
     
         5 . The composition according to  claim 2  wherein the walls of said microspheres comprise albumin.  
     
     
         6 . The composition according to  claim 2  obtainable by spray-drying a wall-forming material in combination with a blowing agent.  
     
     
         7 . The composition according to  claim 2  wherein said microspheres comprise a bioactive agent.  
     
     
         8 . The composition according to  claim 7 , wherein said microspheres comprise a protein or peptide.  
     
     
         9 . The composition according to  claim 7 , wherein said microspheres comprise an active agent selected from the group consisting of insulin, growth hormone and interferon.  
     
     
         10 . An inhaler comprising an inhalable formulation of microspheres wherein said microspheres have a wall thickness of 100 to 500 nm, and a bulk density of no more than 0.1 g/cm 3  and wherein said microspheres comprise a bioactive agent.  
     
     
         11 . The inhaler according to  claim 10 , wherein the formulation comprises the microspheres as the sole or the predominant component thereof.  
     
     
         12 . A method for pulmonary administration of a bioactive agent wherein said method comprises the administration to the lungs of a composition which comprises microspheres having a wall thickness of 100 to 500 nm and a bulk density of no more than 0.1 g/cm 3 , wherein said microspheres further comprise a bioactive agent.  
     
     
         13 . (previously presented) The method according to  claim 12 , wherein the mean geometric diameter of said microspheres is less than 20 μm.  
     
     
         14 . A method for pulmonary administration of a bioactive agent wherein said method comprises the administration to the lungs of a composition which comprises microspheres having a wall thickness of 43.5 to 261 nm and a bulk density of no more than 0.1 g/cm 3 , wherein said microspheres further comprise a bioactive agent.  
     
     
         15 . The method according to  claim 12 , wherein the walls of said microspheres comprise albumin.  
     
     
         16 . The method according to  claim 12 , wherein said microspheres are obtainable by spray-drying a wall-forming material, in combination with a blowing agent.  
     
     
         17 . The method according to  claim 12 , wherein said microspheres comprise a protein or peptide.  
     
     
         18 . The method according to  claim 12 , wherein said microspheres contain a bioactive agent selected from the group consisting of insulin, growth hormone and interferon.  
     
     
         19 . A method for diagnosis wherein said method comprises administering to a patient in need of such diagnosis, a composition which comprises microspheres having a wall thickness of 100 to 500 nm and a bulk density of no more than 0.1 g/cm 3 .  
     
     
         20 . The method according to  claim 19 , wherein the mean geometric diameter of said microspheres is less than 20 μm.  
     
     
         21 . A method for diagnosis wherein said method comprises administering to a patient in need of such diagnosis, a composition which comprises microspheres having a wall thickness of 43.5 to 261 nm and a bulk density of no more than 0.1 g/cm 3 .  
     
     
         22 . The method according to  claim 19 , wherein the walls of said microspheres comprise albumin.  
     
     
         23 . The method according to  claim 19 , wherein said microspheres are obtainable by spray-drying a wall-forming material, in combination with a blowing agent.  
     
     
         24 . A method for preparing microparticles, wherein said method comprises spray-drying wall-forming materials and wherein said method further comprises inclusion of a blowing agent in the feedstock for spray-drying.  
     
     
         25 . The method according to  claim 24 , wherein said blowing agent is selected from the group consisting of ammonium acetate, ammonium carbonate, and acids.  
     
     
         26 . The method according to  claim 24 , wherein said wall-forming material is albumin.  
     
     
         27 . A composition comprising microspheres, wherein said microspheres have a wall thickness of 100 to 500 nm, and a bulk density of no more than 0.3 g/cm 3 .  
     
     
         28 . The composition according to  claim 2  wherein the bulk density is no more than 0.05 g/cm 3 .