Amid health concerns, FDA reviews safety of several heavily used anemia drugs.

F or the second time in 3 years, the U.S. Food and Drug Administration is reviewing the safety of a class of widely used anemia drugs. Earlier this year, the agency added the highest level of warning , a so-called black box, to the label of all three erythropoiesis-stimulating agents (ESAs). At the request of the agency, the Oncologic Drug Advisory Committee (ODAC) met last week to evaluate the drug's safety and dosing. The new wave of concern was triggered by the release of data from several random-ized controlled trials, which showed that patients taking ESAs might be at higher risk of heart attacks or death if their target hemoglobin was above a certain level. Three of the trials were shut down early because of concerns about the health risks. This added to results from two previous studies that also suggested there were problems. Three ESAs, all forms of the human hormone erythropoietin, are currently approved in the U.S. for anemia in chronic renal failure patients and cancer patients treated with che-motherapy (but not for anemia caused by the cancer itself). The original label for these drugs specifi ed that the target range for hemoglobin was between 10 and 12 g/dL in both kidney failure and cancer patients. Although anemia in women is defi ned as a hemoglobin level below 12 g/dL and in men as below 13.5 g/dL, clinicians say that it is not clear if a patient's quality of life would improve by raising his hemoglobin above 12 g/dL. The recently reported trials were aimed at increasing the target hemoglobin above 12 g/dL (and gaining approval for a new group of cancer patients who have anemia that is not due to current or recent therapy). The data from both old and new trials suggest that the use of ESAs to elevate a pa tient's hemoglobin above 12 g/dL is associated with an increased risk of death or serious cardiac and thrombotic events in both chronic renal failure and cancer patients. Surprisingly, cancer patients who received ESAs to increase their levels to 12 g/dL or higher had a shorter time to disease progression, lower overall survival, and higher mortality than those given a placebo. The agency went ahead with the labeling revisions before the ODAC meeting because the emerging data " had a consistent theme, which was that targeting the higher hemoglo-bin was associated with harm, " said Patricia …