Amgen wins Epogen case over Transkaryotic and Aventis

Amgen reported on October 15, 2004 that federal district court judge William G. Young (D. Mass.) ruled in its favor in a remand from the Federal Circuit in a patent infringement suit against Transkaryotic Therapies Inc. (TKT) and Aventis Pharmaceuticals Inc. over claims of two of Amgen's product patents on erythropoietin (EPOGEN) and claims of two patents on the production of erythropoietin. The accused product in question was Dynepo (epoetin delta), the Gene-Activated(R) erythropoietin product of Transkaryotic for the treatment of anemia. Transkaryotic intends to appeal to the Federal Circuit.

From a press release by Transkaryotic:

"Courts should not create thirty-five year monopolies by allowing
companies to radically expand their patent claims more than a decade after filing an application. I believe today's decision misreads the law, discourages innovation, exports biotechnology manufacturing jobs overseas, and denies patients in the United States an important alternative product," said Michael J. Astrue, President and Chief Executive Officer of TKT. "We will appeal."
In January 2003, the Federal Circuit issued a decision affirming in part and reversing in part the District Court's initial January 2001 decision and remanding the case for further proceedings. The Federal Circuit instructed the District Court to reconsider infringement and validity of certain of Amgen's patents.

The District Court on remand found with respect to:
* U.S. Patent No. 5,955,422, that the patent is valid. The Federal Circuit had affirmed the District Court's finding of infringement of one claim, but remanded to reconsider validity of the patent.
* U.S. Patent No. 5,756,349, that the patent is valid and is literally infringed. The Federal Circuit had affirmed the District Court's finding of infringement of certain claims, and remanded to reconsider validity of the patent and infringement of certain other claims.
* U.S. Patent No. 5,618,698, that Aventis' and TKT's process infringes certain claims. The Federal Circuit had remanded to reconsider infringement.
* U.S. Patent No. 5,621,080, that the claims of the patent are valid.
The District Court issued an opinion in October 2003 that Aventis and TKT infringed under the doctrine of equivalents. The Federal Circuit had remanded to reconsider validity and infringement under the doctrine of equivalents.

**Earlier Federal Circuit decision

In Amgen v. Hoechst Marion Roussel, 2003 US App LEXIS 118, the Federal Circuit addressed written description issues related to Lilly, 119 F.3d 1559 and Enzo-II, 296 F.3d 1316 and determined a presumption of enablement for for both claimed and unclaimed disclosures in prior art patents. A technical issue in the case was that the Amgen work disclosed production of human EPO by introducing exogenous DNA into a number of different mammalian and vertebrate host cells but TKT produced its EPO product, Gene-Activated EPO, utilizing endogenous, as opposed to exogenous, DNA.

One issue on remand was the question of enablement of the Sugimoto patent. Because the initial district court decision did not recognize the presumption of enablement and instead placed the burden of proving enablement on TKT, the Federal Circuit had remanded and instructed the lower court to reconsider invalidity under section 102 in view of Sugimoto, with Amgen bearing the burden of proof on nonenablement, rather than the patent challenger TKT having to prove enablement.

**UPDATE on Oct. 22, 2004

The patentlyobvious blog of Dennis Crouch reports that Amgen lost its parallel British case at the House of Lords (Kirin-Amgen v. Hoechst Marion). Further, it is reported that the House of Lords has rejected the "doctrine of equivalents."