update.....
  Wednesday April 26, 2:17 pm Eastern Time
  Company Press Release
  Federal Judge Rules Hoechst and TKT Infringe Amgen's EPO Patent
  THOUSAND OAKS, Calif.--(BUSINESS WIRE)--April 26, 2000--Amgen (NASDAQ:AMGN - news) today announced that Judge William G. Young of the U.S. District Court of Massachusetts in Boston granted Amgen's motion for summary judgment of literal infringement. The District Court ruled that the Hoechst Marion Roussel (Hoechst, now known as Aventis) and Transkaryotic Therapies (TKT) pharmaceutical composition containing erythropoietin infringes claim 1 of U.S. Patent No. 5,955,422. With respect to claims 1 and 4 of U.S. Patent No. 5,756,349, which relates to vertebrate cells capable of producing erythropoietin, the Court denied summary judgment and deferred the issue until trial. 
  ``We are pleased with the Court's ruling,'' said Gordon Binder, Amgen's Chairman and Chief Executive Officer. ``This is a first but important step in the final determination of Amgen's claims against Hoechst and TKT.'' 
  Now that the issue of infringement of claim 1 of the `422 patent has been determined, the upcoming trial will focus on the validity and enforceability of this claim, as well as the infringement, validity and enforceability of the remaining four patents-in-suit. The trial is currently scheduled to begin May 15, 2000. 
  Amgen markets EPO in the United States as EPOGEN© (Epoetin alfa) for the treatment of anemia associated with chronic renal failure for people on kidney dialysis. 
  Amgen is a global biotechnology company that discovers, develops, manufactures and markets cost-effective human therapeutics based on advances in cellular and molecular biology. 
  EDITOR'S NOTE: An electronic version of this news release may be accessed via our web site at www.Amgen.com. Visit the Corporate Center and click on Amgen News. Journalists and media representatives may sign up to receive all news releases electronically at time of announcement by filling out a short form in the Amgen News section of the web site. 
  Contact: 
       Amgen, Thousand Oaks      David Kaye, 805/447-6692 (media)      Cary Rosansky, 805/447-4634 (investors) |