Microparticle protection of therapeutic agents

Abstract

The present invention is directed to the use of microparticles to protect the pharmaceutical effectiveness of a pharmaceutically active agent. According to one embodiment, a pharmaceutically acceptable suspension is provided that comprises microparticles and a pharmaceutically active agent. This pharmaceutically acceptable suspension is then exposed to a component or condition that is incompatible with the pharmaceutically active agent, such that the microparticles provide a pharmaceutical effectiveness that is greater than it would have been in the absence of the microparticles. Preferably, the microparticles result in a pharmaceutical effectiveness of the pharmaceutically active agent that is at least 10% greater than the pharmaceutical effectiveness of the pharmaceutically active agent would have been in the absence of the microparticles. Polymer microparticles, such as polystyrene microparticles, are one preferred class of microparticles. The microparticles preferably range from 0.01 to 100 microns in largest dimension, more preferably 0.1 to 10 microns in largest dimension. The microparticles are preferably provided in an amount of 0.1 to 1 wt % within the suspension. Agents comprising polynucleotides, including cells, plasmids and viral vectors, are a preferred class of pharmaceutically active agent. Other embodiments on the invention are directed to pharmaceutically acceptable suspensions, medical devices for parenteral injection, and methods of treatment.

1 . A method of treatment comprising: 
 providing a pharmaceutically acceptable suspension comprising a pharmaceutically active agent and microparticles;    providing a medical device having a component that is incompatible with said pharmaceutically active agent; and    parenterally injecting said pharmaceutically active agent into a patient from said device while at the same time removing said microparticles from said pharmaceutically acceptable suspension.    
     
     
         2 . The method of  claim 1 , wherein said microparticles are polymer microparticles.  
     
     
         3 . The method of  claim 1 , wherein said microparticles are polystyrene microparticles.  
     
     
         4 . The method of  claim 1 , wherein the microparticles range from 0.1 to 10 microns in largest dimension.  
     
     
         5 . The method of  claim 1 , wherein the pharmaceutically active agent comprises a polynucleotide.  
     
     
         6 . The method of  claim 5 , wherein the polynucleotide is provided within a cell, a plasmid or a viral vector.  
     
     
         7 . The method of  claim 1 , wherein said device is a parenteral injection device selected from a vascular catheter and a syringe.  
     
     
         8 . A pharmaceutically acceptable suspension comprising: 
 a pharmaceutically active agent; and    microparticles, wherein said microparticles are provided to prevent a substantial reduction in pharmaceutical effectiveness of said pharmaceutically active agent upon being exposed to a material or condition that is incompatible with said pharmaceutically active agent.    
     
     
         9 . The pharmaceutically acceptable suspension of  claim 8 , wherein said microparticles are polymer microparticles.  
     
     
         10 . The pharmaceutically acceptable suspension of  claim 8 , wherein said microparticles are polystyrene microparticles.  
     
     
         11 . The pharmaceutically acceptable suspension of  claim 8 , wherein the microparticles range from 0.1 to 10 microns in largest dimension.  
     
     
         12 . The pharmaceutically acceptable suspension of  claim 8 , wherein the pharmaceutically active agent comprises a polynucleotide.  
     
     
         13 . The pharmaceutically acceptable suspension of  claim 12 , wherein the polynucleotide is provided within a cell, a plasmid or a viral vector.  
     
     
         14 . An ampoule containing the pharmaceutically acceptable suspension of  claim 8 .  
     
     
         15 . A device for parenteral injection comprising: 
 a pharmaceutically acceptable suspension comprising a pharmaceutically active agent and microparticles;    a device component that contacts said suspension and is incompatible with said pharmaceutically active agent; and    a separator, said separator acting to remove said microparticles from said pharmaceutically acceptable suspension prior to parenteral injection.    
     
     
         16 . The device of  claim 15 , wherein said microparticles are polymer microparticles.  
     
     
         17 . The device of  claim 15 , wherein the microparticles range from 0.1 to 10 microns in largest dimension.  
     
     
         18 . The device of  claim 15 , wherein the pharmaceutically active agent comprises a polynucleotide.  
     
     
         19 . The device of  claim 15 , wherein said device is a parenteral injection device selected from a vascular catheter and a syringe.