Teva Pharmaceutical Industries Ltd has sued Indian drug makers, including Ranbaxy Laboratories [Get Quote] and Dr Reddy's, for alleged patent violation of ingredients used in Coreg, used for treatment of cardiovascular diseases.

"We have sued Indian as well as other international pharmaceutical companies," a spokesperson for the Israeli pharmaceutical company told PTI.

Although the spokesperson did not name the companies, media reports said Ranbaxy Laboratories, Dr Reddy's Laboratories, Lupin, Orchid Chemicals and Pharmaceuticals, Cadila Pharmaceuticals, USV Ltd and Wanbury have been sued for alleged infringement of its patent for carvedilol active pharmaceutical ingredient, the main constituent in Coreg.

Teva, which owns various patents on carvedilol API, filed separate cases with the US district court in New Jersey against the Indian carvedilol API manufacturers, as well as Coreg generic drug manufacturers.

The Israeli pharmaceutical major told the court that the defendants failed to provided samples of their carvedilol API or furnish information regarding the processes through which it is made despite conditions of confidentiality.