Swiss pharmaceutical company Roche Holding AG and OSI Pharmaceuticals Inc. said Monday the cancer drug Tarceva won approval from the European Commission as a treatment for pancreatic cancer in combination with standard chemotherapy.

Pancreatic cancer has the highest one-year mortality rate of any cancer and is Europe's sixth-deadliest cancer, the companies said.

"This is a much needed treatment advance for patients suffering with this difficult-to-treat disease," said William Burns, chief executive of Roche's pharmaceuticals unit, in a statement.

In 2002, there were more than 78,000 new cases of pancreatic cancer diagnosed in Europe, with a death rate of approximately 82,000 people per year, Roche said.

Pancreatic cancer is difficult to treat as it is often resistant to chemotherapy and radiotherapy and tends to spread quickly to other parts of the body, leading to a short life expectancy, the company said.

In November, Tarceva received approval from the Food and Drug Administration for the same use. In the U.S., OSI markets the treatment with biotech drugmaker Genentech Inc.

Tarceva is also approved to treat non small cell lung cancer.

Shares in Roche fell 0.3 percent to 232.30 Swiss francs ($185.38) in Zurich trading. Shares of OSI rose 21 cents to $33.39 in early trading on the Nasdaq.