West Coast Editor

Its patent dispute with Amgen Inc. still unresolved, Transkaryotic Therapies Inc. won approval from the European Union to market its erythropoietin product, Dynepo, for anemia in dialysis patients, and for renal patients who have not yet undergone the procedure but the company said launch of the red blood cell booster will be held up pending a final decision by the court.

TKT, of Cambridge, Mass., and Frankfurt, Germany-based partner Aventis Pharma AG, remain embroiled in court skirmishes in the U.S. and abroad with Thousand Oaks, Calif.-based Amgen and its Japanese affiliate, Kirin-Amgen. Stakes are high, with Amgen focused on protecting its blockbuster erythropoietin product, Epogen.

“[TKT] lost that first round in the UK courts, and appeals are being heard this summer,” said Thomas Dietz, analyst with Pacific Growth Equities in San Francisco. “We’ll probably get a ruling from the appeals court at the end of the year or early 2003. If they lose that, then they have another year until the patents expire [in 2004].”

Dietz told BioWorld Today that Dynepo (epoietin delta) will “make it to market eventually, and there’s value in that. How big is the market in Europe? We think it’s about a third of the total sales of [erythropoietin]. A new product could garner $300 million to $350 million in sales. That’s a reasonable penetration.”

In 2001, the U.S. District Court for the District of Massachusetts ruled that Dynepo infringed Amgen patent claims, and the High Court of Justice in the UK ruled that Dynepo infringed one claim of a patent asserted by Kirin-Amgen. Decisions for the appeals are expected by 2003.

TKT is no stranger to the courtroom. In December, the company said a federal judge dismissed patent litigation brought against TKT by Cambridge, Mass.-based Genzyme General over Replagal (agalsidase alfa), the former’s enzyme replacement therapy developed for the treatment of Fabry’s disease. Genzyme’s potentially competing drug candidate is Fabrazyme (agalsidase beta). Replagal, like Fabrazyme, is approved in Europe. (See BioWorld Today, Dec. 18, 2000.)

Both companies have biologics license applications pending in the U.S., and both are seeking orphan drug status for their treatments.

In Europe, Dietz noted, 60 percent of the identifiable market is using Replagal, and “reports of patients developing IgE antibodies to Fabrazyme are expected to continue to erode physicians’ willingness to use that drug first.”

Genzyme, Dietz wrote, “is currently attempting to sell Fabrazyme with the message The same as Replagal,’” an approach that Dietz predicted will “fall flat” in the end.

Dietz told BioWorld Today that, in Europe, “Genzyme isn’t even detailing [the drug] against these guys now.”

The company’s shares (NASDAQ:TKTX) closed Tuesday at 42.56, down 16 cents. Genzyme’s stock (NASDAQ:GENZ) ended at $48.79, down 46 cents.