Tenofovir granules

Abstract

The present invention relates to a granular composition comprising essentially Tenofovir, wherein the composition is devoid of an excipient. Tenofovir granules of the present invention are prepared in twin-screw processor such that the content of total impurities in the prepared granules is less than 2.0%.

We claim: 
     
         1 . A process for preparing a granular composition consisting essentially of Tenofovir devoid of an excipient and with content of total impurities not more than 2.0% in twin screw processor comprising the steps of:
 a. feeding Tenofovir into the intake zone of the twin screw processor;   b. conveying Tenofovir towards the kneading zone and processing it in the kneading zone;   c. conveying Tenofovir from the kneading zone towards the exit;   d. collecting the Tenofovir granules.   
     
     
         2 . The process for preparing granular composition of Tenofovir as claimed in  claim 1  wherein the temperature of the barrel in the twin screw processor is between 25° C. and 60° C. 
     
     
         3 . The process for preparing granular composition of Tenofovir as claimed in  claim 2  wherein the content of Tenofovir isoproxil monoester is not more than 1%; and wherein the content of Tenofovir disoproxil dimer is not more than 0.15%. 
     
     
         4 . The process for preparing granular composition of Tenofovir as claimed in  claim 2  wherein the content of adenine is not more than 0.15%, the content of Tenofovir isoproxil monoester is not more than 1%, the content of Tenofovir disoproxil ethyl ester is not more than 0.15%, the content of Tenofovir isopropyl isoproxil is not more than 0.3%, the content of Tenofovir disoproxil carbamate is not more than 0.15% and the content of Tenofovir disoproxil dimer is not more than 0.15%. 
     
     
         5 . The process for preparing granular composition of Tenofovir as claimed in  claim 1  wherein the said composition is stable after storage at 40° C. and 75% Relative Humidity for a period of at least 3 months. 
     
     
         6 . The process for preparing granular composition of Tenofovir as claimed in  claim 1  wherein the said composition is stable after storage at 25° C. and 60% Relative Humidity for a period of at least 3 months. 
     
     
         7 . The process for preparing granular composition of Tenofovir as claimed in  claim 1  wherein the said composition is stable after storage at 2° C. to 8° C. for a period of at least 3 months.