BOSTON, Nov 8 (Reuters) The warning labels have been strengthened on anemia drugs made by Amgen Inc and Johnson&Johnson to reflect concerns they may increase the risk of heart attacks, stroke and death, the companies and US regulators said today.
The drugs, known as erythropoiesis-stimulating agents or EPO drugs, include Amgen's biggest drug Aranesp and an older version, Epogen, and J&J's Procrit.
Amgen, the world's largest biotechnology company by sales, said six new clinical trials have been designed to assess the safety of such drugs when used to treat chemotherapy-induced anemia in specific tumor types.
The updated label for Aranesp includes instructions that therapy should be discontinued following completion of a chemotherapy course, and that no more of the drug should be given than needed to avoid a blood transfusion.
The warnings state that a patient's level of oxygen-carrying hemoglobin should not rise above 12 grams per deciliter of blood for patients with cancer. They also add that the risks of shortened survival and cancer progression ''have not been excluded'' when the drugs are given to achieve hemoglobin of less than 12 grams per deciliter.
Aranesp is approved to treat anemia associated with chemotherapy and kidney disease. Epogen is used to treat anemia associated with kidney disease. The two drugs generated 2006 sales of 4.1 billion dollars in 2006, but those sales have been falling sharply due to safety concerns.
Worldwide Aranesp sales fell 23 per cent to 818 million dollars in the third quarter as doctors stopped using the drug in cancer patients who were not undergoing chemotherapy and as other regulatory and reimbursement changes began to take a toll.
Epogen sales fell 5 per cent in the third quarter to 602 million dollars, while sales of J&J's Procrit plunged 27 per cent to 380 million dollars.
Concerns over the class of drugs cropped up when a study showed increased risk of death in cancer patients whose anemia was not caused by chemotherapy. Concerns that the medicines were being overused in kidney dialysis patients were addressed by new use guidelines and reimbursement restrictions.
Amgen did dodge a bullet aimed at its anemia franchise last month, when a federal jury ruled that the patents covering its EPO drugs were valid and infringed by a rival medicine Swiss drugmaker Roche Holding AG was hoping to sell in the United States.
Amgen said it plans to submit new evidence to the Centers for Medicare and Medicaid Services in the hope the agency will reverse its decision to pay for drugs in cancer patients undergoing chemotherapy when hemoglobin levels fall below 10 grams per deciliter of blood.
Amgen shares were up 38 cents to 56.58 dollars on Nasdaq, while J&J edged up 18 cents to 64.09 dollars on the New York Stock Exchange.
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