Rapid Acting Injectable Insulin Compositions

Abstract

Injectable insulin formulations with improved stability and rapid onset of action are described herein. The formulations may be for subcutaneous, intradermal or intramuscular administration, In the preferred embodiment, the formulations are administered via subcutaneous injection. The formulations contain insulin in combination with a chelator and dissolution agent, and optionally additional excipients. In the preferred embodiment, the formulation contains human insulin, a zinc chelator such as EDTA and a dissolution agent such as citric acid. These formulations are rapidly absorbed into the blood stream when administered by subcutaneous injection. In the preferred embodiment, the insulin is provided as a dry powder in a sterile vial. This is mixed with a diluent containing a pharmaceutically acceptable carrier, such as water, a zinc chelator such as EDTA and a dissolution agent such as citric acid shortly before or at the time of administration. In another embodiment, the insulin is stored as a frozen mixture, ready for use upon thawing.

1 . An injectable insulin composition comprising insulin and an effective amount of a dissolution agent and a zinc chelator to enhance uptake and transport of the insulin through epithelial cells as compared to insulin in combination with a zinc chelator and HCl.  
     
     
         2 . The composition of  claim 1 , wherein the agent is selected from the group consisting of human insulin and insulin analogs.  
     
     
         3 . The composition of  claim 2 , wherein the agent is human insulin.  
     
     
         4 . The composition of  claim 1 , wherein the chelator is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), EGTA, trisodium citrate (TSC), alginic acid, alpha lipoic acid, dimercaptosuccinic acid (DMSA), CDTA (1,2-diaminocyclohexanetetraacetic acid).  
     
     
         5 . The composition of  claim 4 , wherein the chelator is ethylenediaminetetraacetic acid (EDTA).  
     
     
         6 . The composition of  claim 1 , wherein the dissolution agent is an acid selected from the group consisting of acetic acid, ascorbic acid, citric acid, glutamic, succinic, aspartic, maleic, fumaric, and adipic acid.  
     
     
         7 . The composition of  claim 6  wherein the dissolution agent is citric acid.  
     
     
         8 . The composition of  claim 1  wherein the chelator is present in a concentration range corresponding to between 2.42×10 −4  M and 9.68×10 −2  M EDTA.  
     
     
         9 . The composition of  claim 1  wherein the dissolution agent is present in a concentration range corresponding to between 9.37×10 −4  M and 9.37×10 −2 M citric acid.  
     
     
         10 . The composition of  claim 1  wherein the zinc chelator is EDTA and the dissolution agent is citric acid and the chelator is present in a concentration of between 2.42×10 −4  M and 9.68×10 −2  M EDTA and the dissolution agent is present in a concentration of between 9.37×10 −4  M and 9.37×10 −2 M citric acid.  
     
     
         11 . The composition of  claim 1  wherein the insulin is provided in a dry powder in a first container and at least one of the chelator and dissolution agent are provided in a second container containing a diluent.  
     
     
         12 . The composition of  claim 1  provided as a frozen pharmaceutically acceptable agent for treatment of a diabetic.  
     
     
         13 . A method of treating a diabetic individual comprising injecting an effective amount of an injectable insulin composition comprising insulin and an effective amount of a dissolution agent and a zinc chelator to enhance uptake and transport of the insulin through epithelial cells as compared to insulin in combination with a zinc chelator and HCl.