The Food and Drug Administration issued strict new warnings yesterday about overuse of widely prescribed anemia drugs after a flurry of recent studies suggested they might cause heart problems or hasten the death of cancer patients. The agency said that a black box warning the strongest kind had been added to the labels of the drugs and that doctors should use the lowest possible dose needed to help patients avoid blood transfusions. It also said it was re-evaluating the validity of claims in the labels and in advertisements that the drugs can raise energy levels or otherwise improve a patient s quality of life. Almost one million Americans take one of the drugs, which are mostly used to treat anemia caused by kidney failure or chemotherapy. The drugs are darbepoetin alfa, sold as Aranesp by Amgen, and epoetin alfa, sold as Epogen by Amgen and as Procrit by Johnson & Johnson. Both drugs are genetically engineered forms of erythropoietin or Epo, a substance made by the human kidney that increases the production of red blood cells, which ferry oxygen to the body s tissues. Sales of the drugs worldwide totaled about $10 billion last year, making Epo the most lucrative product ever produced by the biotechnology industry. It is also the largest drug expense for Medicare, which spent $2 billion in 2005 just for the use of Epogen in kidney dialysis patients. The drugs, given by injection, have been heavily advertised, and there is evidence that they have been overused, in part because dialysis centers and oncologists can make money by using more of the drug. The recommendation that we treat our patients largely to avoid transfusion is a seismic change in our management, said Dr. Daniel Coyne, a professor at Washington University in St. Louis. F.D.A. officials stressed that the drugs main safety risks seemed to occur when they were used to raise hemoglobin above 12 grams per deciliter of blood. The labels for the drugs had recommended not exceeding that level, and the new labels emphasize this strongly. Hemoglobin is the component of red blood cells that carry oxygen.
