Method for muscle delivery of drugs, nucleic acids and other compounds

Abstract

A method is disclosed for delivering molecules such as pharmaceutical drugs and nucleic acids into skeletal muscle in vivo. The molecule is first injected into the muscle at one or multiple sites. Immediately or shortly after injection, electrodes are placed flanking the injection site and a specific amount of electrical current is passed through the muscle. The electrical current makes the muscle permeable, thus allowing the molecule to enter the cell. In the case where nucleic acid is injected, the efficiency of transfer permits expression of protein encoded by the nucleic acid in an amount that exhibits systemic biological activity and which generates a robust immune response.

1 . A method of delivering a molecule to skeletal muscle of a mammal in vivo, comprising: 
 (a) delivering a pre-determined amount of a composition containing a pharmaceutical agent into skeletal muscle of a mammal, whereby a penetration site and a treatment region are created;    (b) positioning electrodes spaced from said penetration site such that current traveling between the electrodes passes through the treatment region; and    (c) electrically stimulating the muscle with an electrical current.    
   
   
       2 . The method of  claim 1 , wherein said current generates a field strength in the range of from about 5 V/cm to less than about 250 V/cm.  
   
   
       3 . The method of  claim 1 , wherein said electrical stimulation is delivered in the form of a single pulse.  
   
   
       4 . The method of  claim 3 , wherein said pulse has a duration of between about 50 μs and about 5000 μs.  
   
   
       5 . The method of  claim 1 , wherein said electrical stimulation is delivered in the form of between about 2 to about 30,000 pulses.  
   
   
       6 . The method of  claim 5 , wherein said pulses have a total duration of between about 10 ms and about 12,000 ms.  
   
   
       7 . The method of  claim 6 , wherein said pulses are delivered in the form of at least two trains.  
   
   
       8 . The method of  claim 7 , wherein the frequency of said electrical stimulation said pulses is between about 0.5 Hz and about 1000 Hz.  
   
   
       9 . The method of  claim 1 , wherein said pharmaceutical agent is a nucleic acid.  
   
   
       10 . The method of  claim 9 , wherein said nucleic acid encodes a protein.  
   
   
       11 . (canceled)  
   
   
       12 . The method of  claim 10 , wherein said encoded protein is expressed by cells in the treatment region following step c.  
   
   
       13 . The method of  claim 1 , wherein said electrical stimulation comprises a fixed electrical current that results in a field strength that varies with tissue resistance, said field strength varying from about 5 V/cm to about 250 V/cm.  
   
   
       14 - 19 . (canceled)  
   
   
       20 . A method of in vivo delivery of an expression vector encoding a peptide or polypeptide, comprising: 
 (a) injecting one or more expression vectors into skeletal muscle of a mammal, whereby a penetration site and a treatment region are created, wherein said expression vector is capable of directing expression of a peptide or polypeptide encoded by said vector in cells of said mammal;    (b) positioning electrodes spaced from said penetration site such that current traveling between the electrodes passes through the treatment region; and    (c) electrically stimulating the muscle with an electrical current,    whereby performance of steps (a)-(c) result in delivery of said expression vector to cells of said mammal.    
   
   
       21 . The method of  claim 20 , wherein said current generates a field strength in the range of from about 5 V/cm to less than about 250 V/cm.  
   
   
       22 - 34 . (canceled)  
   
   
       35 . The method of  claim 20 , wherein said polypeptide is a protein.  
   
   
       36 . The method of  claim 35 , wherein said protein is secreted from the cells in which it is expressed.  
   
   
       37 . The method of  claim 36 , wherein said protein is EPO.  
   
   
       38 . The method of  claim 20 , wherein said peptide or polypeptide is antigenic in said mammal.  
   
   
       39 . The method of  claim 20 , wherein said method further comprises expression of said encoded peptide or polypeptide in said cells.  
   
   
       40 . A method for vaccinating a mammal, comprising: 
 (a) delivering a pre-determined amount of a composition containing a pharmaceutical agent into skeletal muscle of a mammal, whereby a penetration site and a treatment region are created, wherein the pharmaceutical agent is selected from the group consisting of an expression vector capable of directing expression of an antigenic peptide or polypeptide encoded by said vector in cells of said mammal;    (b) electrically stimulating the skeletal muscle by positioning electrodes spaced from said penetration site such that electrical current traveling between the electrodes the treatment region generates an electrical field having a field strength in the range of from about 5 V/cm to less than about 250 V/cm; and    (c) expressing said antigenic peptide or polypeptide encoded by said vector in said cells, thereby vaccinating said mammal.