US 11,717,524 B1
Varenicline compound and process of manufacture thereof
Joseph Prabahar Koilpillai, Tamil Nadu (IN); Sayuj Nath, Tamil Nadu (IN); Satish Patil, Tamil Nadu (IN); Somasundaram Muthuramalingam, Tamil Nadu (IN); Selvakumar Viruthagiri, Tamil Nadu (IN); and Mohankumar Lakshmanan, Tamil Nadu (IN)
Assigned to Par Pharmaceutical, Inc., Chestnut Ridge, NY (US)
Filed by Par Pharmaceutical, Inc., Chestnut Ridge, NY (US)
Filed on Sep. 9, 2022, as Appl. No. 17/930,824.
Application 17/930,824 is a division of application No. 17/721,857, filed on Apr. 15, 2022.
Claims priority of provisional application 63/319,043, filed on Mar. 11, 2022.
Int. Cl. A61K 31/55 (2006.01); A61K 47/38 (2006.01); A61K 47/02 (2006.01); A61K 47/12 (2006.01); C07D 471/18 (2006.01)
CPC A61K 31/55 (2013.01) [A61K 47/02 (2013.01); A61K 47/12 (2013.01); A61K 47/38 (2013.01); C07D 471/18 (2013.01)] 30 Claims
 
1. A method of making a varenicline tartrate tablet comprising less than 50 ppm of nitrosamine impurities, the method comprising:
(a) mixing varenicline free base with tartaric acid to form varenicline tartrate; and
(b) means for reducing the nitrosamine impurities to less than 50 ppm per tablet as measured by LC-ESI-HRMS Method;
wherein the means comprises an acid-base treatment.