Glenmark settles patent suit with Sepracor over insomnia drug

Drug firm Glenmark Pharmaceuticals today said it has entered into a settlement agreement with American firm Sepracor, which could pave way for the Indian firm to launch generic eszopiclone tablets, used in treating insomnia, in the US market.

"Sepracor Inc has entered into a settlement and licence agreement with Glenmark to resolve a patent infringement suit related to its filing of an abbreviated new drug application (ANDA) with the United States Food and Drug Administration to market generic Eszopiclone tablets," Glenmark said in a filing to Bombay Stock Exchange.

According to IMS health data, Sepracor, which markets eszopiclone tablets under the brand name Lunesta in the US market, had annual sales of $741 million for the 12 month period ending March 2010.

 Under the settlement, Glenmark would be permitted to launch its generic version of eszopiclone on November 30, 2013, which is two and half months prior to the expiry of Sepracor's US patent or May 30, 2014 if Sepracor obtains pediatric exclusivity for Lunesta, it said.

Pediatric exclusivity is an add-on to an existing marketing exclusivity or patent protection.

The two firms' settlement agreement is subject to approval by the District Court of New Jersey and it would permit Glenmark to launch its generic product earlier under certain circumstances.

The tablets are available in 1mg, 2mg and 3mg strengths and are the second highest selling branded prescription medication in its class in the US market.

Shares of Glenmark were today trading at Rs 268.50 on BSE on late afternoon trade, down 0.06 per cent from its previous close.