Switzerland's Roche has been blocked from launching a new anaemia drug in the United States after a Boston jury found it infringed patents belonging to rival Amgen.
The Basel-based firm is now considering its options, including a possible appeal, and still maintains that the facts and the law support its position in the dispute.
The jury, following a six-week trial, announced on Tuesday that it was of the opinion that all of the American firm's patent claims were valid and that Roche's own Mircera drug infringed three of them.
The judge who presided over the case had set the tone early on, issuing a pre-trial ruling that Mircera infringes the most important of four Amgen patents that were in dispute. The jury would have had to find that patent invalid for Roche to have any chance of prevailing.
The judge said that if the Swiss firm wishes to contest the ruling, it must appeal within 60 days.
Roche said in a statement that it was disappointed and was evaluating its legal options. "Amgen has had an extended monopoly for the last 20 years in the US blocking new therapeutic options to treat anaemia from being introduced," said William Burns, the chief executive of Roche's pharmaceutical division.
During the hearings, Roche had maintained that its product not only did not infringe Amgen's patents but it sought to convince the jury that these patents were invalid.
Amgen, the world's biggest biotechnology firm, insisted its patents are valid, based on innovations made by one of its scientists.
"This is a long-sought and well-deserved vindication for Amgen," said the company's lead attorney, Lloyd Day.
Amgen said it plans to seek an injunction to prevent Roche from importing Mircera into the United States in violation of its upheld patents.
The Swiss company has a definite interest in entering the market with its Mircera product. Amgen's two drugs, Aranesp and Epogen, generated alone sales in 2006 of nearly $7 billion (SFr8.22 billion), roughly half of its total revenue.
Roche won approval for Mircera in the European Union in July to treat patients with kidney disease. According to the Wall Street Journal, the drug could eventually replace similar Roche pharmaceuticals, which posted sales of about $1.7 billion last year.
The Swiss company also believes its product could be a big seller because it needs to be injected only once or twice a month, compared to the weekly dosing required of Amgen's drugs.
The drugs, used to combat anaemia in chemotherapy and kidney patients, are man-made versions of a human hormone called erythropoietin, or EPO, that stimulates production of oxygen-carrying red blood cells.
EPO has been used by athletes as a performance-enhancing drug and is considered a form of doping as it boosts endurance. Misuse can also lead to health problems, including a heightened risk of cardiovascular problems as the hormone thickens the blood.
Sales of Amgen's drugs were hit earlier this year though hit by concerns they were being overused and are facing new restrictions from government agencies and insurance companies.
The US Food and Drug Administration, which oversees drug approval, also ordered in March that boxes of the products be issued with so-called black box warnings - the highest level of warning for pharmaceuticals in the United States – over potential side effects.
swissinfo with agencies
Roche 2006 results:
Net profit: SFr9.17 billion
Full-year sales: SFr42.04 billion
Operating profit: SFr11.73 billion
Erythropoietin or EPO is a hormone that is produced by the kidney and regulates red blood cell production.
In the 1970s, American scientists helped establish that EPO stimulates the production of red cells in bone marrow and could lead to a treatment for anaemia in humans.
Amgen later developed the first commercially available synthetic EPO.
In the late 1980s, it led though to an entirely new form of blood doping.
Easily injected under the skin, pharmaceutical EPO can boost hematocrit levels for six weeks or longer, and its use is now believed by many to be widespread in endurance sports.
EPO is also not free of health hazards: excessive use of the hormone can cause polycythemia, a condition where the level of red blood cells in the blood is abnormally high.
This causes the blood to be thicker than normal, inflicting strain on the heart. Some elite athletes who died of heart failure were found to have unnaturally high red blood cell concentrations in their blood.