Stabilized liquid formulation of levothyroxine

Abstract

The present invention relates to stabilized liquid formulations of Levothyroxine or a pharmaceutically acceptable salt thereof, intended for parenteral administration. Further this invention also describes process of preparing such compositions.

1 - 6 . (canceled) 
     
     
         7 . A stable liquid parenteral pharmaceutical formulation of Levothyroxine comprising:
 (i) levothyroxine sodium in a concentration of less than 0.1% w/v;   (ii) one or more excipients selected from the group comprising stabilizing agents and solubilising agents;   (iii) one or more buffering agents;   (iv) one or more solvents, and optionally   (iv) one or more pharmaceutically acceptable excipients, wherein the content of total impurities is less than 2% w/w, when stored at 60° C. for 1 week.   
     
     
         8 . The formulation of claim  1 , wherein the content of total impurities is less than 2% w/w, when stored at 60° C. for 1 month. 
     
     
         9 . The formulation of claim  1 , wherein buffering agent is selected from the group comprising arginine, alanine, histidine, glycine and lysine, citrate, glutamate, bicarbonate, tartrate, benzoate, lactate, gluconate, TRIS, acetate, meglumine, borate and phosphate buffer. 
     
     
         10 . The formulation of claim  1 , wherein the solubilising agent comprises a cyclodextrin. 
     
     
         11 . The formulation of claim  4 , wherein the cyclodextrin is selected from α, β and γ-cyclodextrin and cyclodextrins modified with alkyl-, hydroxyalkyl-, dialkyl-, and sulfoalkyl-ether modified cyclodextrins. 
     
     
         12 . The formulation of claim  1 , wherein one or more solvents are selected from the group comprising water, polyethylene glycol, ethanol, propylene glycol and glycerine. 
     
     
         13 . A stable liquid parenteral pharmaceutical formulation of Levothyroxine comprising:
 (i) levothyroxine sodium in a concentration of less than 0.1% w/v;   (ii) one or more excipients selected from the group comprising stabilizing agents and solubilising agents;   (iii) one or more buffering agents selected from the group comprising arginine, alanine, histidine, glycine and lysine, citrate, glutamate, bicarbonate, tartrate, benzoate, lactate, gluconate, TRIS, acetate, meglumine, borate and phosphate buffer;   (iv) one or more solvents selected from the group comprising water, polyethylene glycol, ethanol, propylene glycol and glycerine, and optionally   (iv) one or more pharmaceutically acceptable excipients, wherein the content of total impurities is less than 2% w/w, when stored at 60° C. for 1 week.