AMGEN PREVAILS IN PATENT SUIT AGAINST TKT, AVENTIS

A federal appeals court has affirmed a lower court decision that an anemia drug co-developed by Aventis Pharmaceuticals and Transkaryotic Therapies (TKT) infringes on Amgen's patents for its anemia drug Epogen.

The ruling by the U.S. Court of Appeals for the Federal Circuit affirms a 2004 decision by the U.S. District Court for the District of Massachusetts in Boston. The ruling pertains to two of the patents the district court had considered in its 2004 decision. Amgen sued TKT and Aventis for infringing on its patents for Epogen (erythropoietin) with their anemia drug Dynepo. The drugmakers argued that since their drug was produced using human cells, it did not infringe on Amgen's patents. TKT said the court's ruling allows Amgen to create a monopoly on erythropoietin products and appealed the decision to the Federal Circuit court.

The 2004 district court ruling focused on the validity of two patents on erythropoietin and the validity and infringement of two more patents with claims to production of erythropoietin, according to Amgen. The judge's ruling upheld the enforceability of all four patents.

Amgen did not fare so well in a more recent case. The U.S. International Trade Commission (ITC) ruled in July that Roche's importation and use of its experimental anemia drug CERA in the U.S. does not violate Amgen's patents on its anemia drug Epogen because Roche was studying it for clinical trial purposes only, Amgen said. The ITC determined that Roche was eligible for a "clinical trial exemption," which means the commission found that Roche's use of the product was only to get FDA approval for its drug.