Fourth generic drugmaker sued for Analeptic Drug Nuvigil

Cephalon Inc. has filed a civil suit for patent infringement against the generic drugmaker Watson Pharmaceuticals Inc. for its analeptic drug Nuvigil, generically known as Armodafinil. The suit filed on Tuesday (January 05, 2009) in the US District Court for the District of Delaware is to prevent Watson from commercializing the generic Vuvigil product prior to the expiration of Orange-Book listed US Patent No. 7,132,570. Approved by the United States FDA in June 2007, Vuvigil total US sales is approximately USD 42 million for the twelve months ending September 30, 2009 according to IMS Health data. Watson is believed to be “First-to-File” applicant for the 100mg and 200mg strengths of a generic Nuvigil and may be entitled to 180 days of market exclusivity for those strengths. Notably, both 100mg and 200mg strengths got the United States FDA approval on March 26, 2009 almost 21 months later than 50mg, 150mg and 250mg strengths.

Nuvigil’s active ingredient, Armodafinil, is (-)-(R) enantiomer of the racemic drug modafinil also marketed by Cephalon under the brand name Provigil. Provigil is likely to face generics from 2012 and it is considered that Cephalon is looking to protect its sales by switching patients to Nuvigil. Already the generic competition for Nuvigil is getting intense. Earlier in December 2009, Cephalon filed similar suits in the US District for the District of Delaware against three generic manufactures, namely, Teva Pharmaceuticals Inc., Mylan, Inc. and Actavis Inc. for infringement of OB listed US Patent Nos. 7,132,570 (the ‘570 patent), 7,297,346 (the ‘346 patent) and RE37,516 (the ‘516 patent).