Glenmark Pharmaceuticals Ltd has informed the BSE in a regulatory filing that Schering Corporation and MSP Singapore Company LLC have filed a suit agains the company in the US District Court for the District of New Jersey, seeking to prevent Glenmark from proceeding with the the commercialisation of its ezetimibe, which is currently marketed by Schering as Zetia.

Glenmark Pharmaceuticals says it had filed an ''abbreviated new drug application'' (ANDA) with the US FDA on 25 October, 2006, the first date on which an ANDA for Ezetimibe could be filed, seeking regulatory approval to market a generic version of ezetimibe.

The company says that its ANDA also included a ''paragraph IV certification'' with respect to patents listed by Schering in the FDA "Orange Book". According to Glenmark, it is "the first and believes the only, applicant to have filed an ANDA for ezetimibe with a paragraph IV certification on October 25, 2006".

In the event that the Indian company successfully challenges Schering''s patent, it will be entitled to a 180-day exclusivity period.

Zetia (ezetimibe) had sales of approximately $1.5 billion in the US based on IMS sales data for the year ending January 2007.