Amgen boosted by EPO hearing

Shares of Transkaryotic Therapies (TKTX) closed Wednesday at $53, down $25.125 (32 percent) on the week, after a U.S. District Court judge adopted modified versions of Amgen's definitions of four patent claim terms related to AGMN's erythropoietin patent infringement suit against TKTX and partner Aventis Pharmaceuticals.

Judge William Young of the U.S. District Court for the District of Massachusetts issued the determinations in a two-day Markman hearing that ended on Tuesday. A Markman proceeding allows the judge to determine how a person of ordinary skill would interpret the scope and meaning of patent claims. ...