Process for preparing efavirenz polymorph
AssigneeHetero Research Foundation
InventorsBandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Kesireddy Subash Chander Reddy
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Abstract
The present invention relates to a process for the preparation of crystalline non-hygroscopic form H1 of efavirenz, and pharmaceutical compositions containing it. In accordance with the present invention efavirenz was dissolved in acetone at 25° C.-30° C., the solution was slowly added to water at 0° C.-5° C., the separated solid was filtered, washed with mixture of acetone and water and dried at 25° C.-35° C. under below 65% relative humidity for 18 hours to give crystalline non-hygroscopic efavirenz form H1.
Claims9
A process for preparation of the non-hygroscopic efavirenz form H1 which comprises:
- a. precipitating from a solution of efavirenz in a C1-C6-alcoholic, C3-C8-ketonic solvent or a mixture thereof by using water as precipitating solvent at below about 15° C., collecting the precipitated solid;
- and
- b. air drying the solid collected to obtain non-hygroscopic crystalline efavirenz form H1
- wherein the air drying is carried out at about 25° C.-35° C. under relative humidity of 40-80% for 14-25 hours.
Dependencies are inferred from the claim text.