APPEALS COURT SIDES WITH AMGEN.

Byline: Evan Pondel Staff Writer

THOUSAND OAKS - Analysts foresee Amgen Inc. as the eventual winner in a U.S. Court of Appeals ruling that Transkaryotic Therapies Inc. and Aventis SA infringed upon two of the biotechnology giant's patents.

The Court of Appeals affirmed on Monday a district court's finding that two of Amgen's patents were infringed upon relating to anemia drug Epogen. But the case was sent back to the lower court to reconsider the validity of some claims, meaning Amgen must again prove that TKT infringed on at least one patent.

``Because the court didn't come to a definitive conclusion, the TKT bulls probably thought the ruling was a positive. But the court's decision is a far cry from a positive for TKT,'' said Bill Tanner, analyst with Leerink Swann & Company in Boston. ``If anything, the ruling will probably be in favor of Amgen once the court makes its final ruling.''

Epogen, a genetically altered form of a naturally occurring protein, erythropoietin, or EPO, bolsters the body's production of red blood cells. At conflict is whether Amgen's patents cover the protein, as TKT claims, or the methods used to manufacture the protein, as Amgen maintains.

The court's ruling on Monday could give Transkaryotic a little more moxie to continue its fight. But Jennifer Chao, an analyst with RBC Capital Markets who thinks the odds favor Thousand Oaks-based Amgen, said a final decision could take several months to several years. ``And unless or until this litigation is resolved in its favor, TKT will not be able to manufacture or market Dynepo (TKT's equivalent of Epogen) in the U.S.,'' Chao said in a note.

Amgen remains confident that it will receive a favorable ruling. ``In light of the appeals court's decision, Amgen continues to believe that it will successfully enforce its patent rights against TKT and Aventis,'' the company said in statement.

Meanwhile, TKT's president said he is pleased with the court's decision. ``The Federal Circuit's decision is very encouraging as we believe it represents a major step in the right direction toward making Dynepo available to patients who can benefit from our therapy,'' said Dr. Richard Selden, president and chief executive officer of TKT, in a statement.

Martin Auster, an analyst with SunTrust Robinson Humphrey in Atlanta, said people were concerned that the court's ruling would have a detrimental consequence for Amgen. ``If anything, the ruling removed this near-term threat,'' he said.

Amgen declined 3 cents to $50.24, while TKT fell $1.79, or 17.9 percent, to $8.21 Tuesday on the Nasdaq market.