NEW YORK (AP) -- Cephalon Inc. said Thursday it is suing Apotex Corp. and Apotex Inc. for infringing Cephalon's patent on the sleep disorder drug Nuvigil.
Cephalon said it filed the lawsuit in U.S. District Court in Delaware after Apotex asked the Food and Drug Administration to approve a generic version of Nuvigil.
By law, the lawsuit automatically delays Food and Drug Administration approval of Apotex's version until either a district court rules on the lawsuit or 30 months pass.
Shares of Cephalon fell 16 cents to close at $58.70.
