SOMX Somaxon Pharmaceuticals, Inc. (MM)

   DOW JONES NEWSWIRES 
 

Somaxon Pharmaceuticals Inc. (SOMX) said it is suing Mylan Pharmaceuticals Inc. (MYL) for trying to market a generic version of its Silenor sleep medication.

The suit filed in the U.S. District Court for the District of Delaware claims Mylan's abbreviated new drug application infringes on Somaxon's patent, according to the company's filing with the Securities and Exchange Commission. In May, Somaxon filed a similar lawsuit against Par Pharmaceutical Inc. (PRX) over that firm's efforts to market its own generic version of Silenor.

Somaxon earlier last month said its first-quarter loss widened sharply on higher costs, though it reported product sales, of which it had none a year earlier.

Somaxon shares fell 6% to $2.05 after-hours Tuesday, after gaining about as much during the session. Mylan shares were unchanged at $23.75 after-hours.

-By Drew FitzGerald, Dow Jones Newswires; 212-416-2909; Andrew.FitzGerald@dowjones.com