Aranesp, Epogen and Procrit Linked to Leukemia in Some PatientsDec 11, 2007 | Parker Waichman LLP
Aranesp, Epogen and Procrit have been linked to yet another deadly side effect. New research suggests that the anemia drugs, known as erythropoiesis-stimulating agents (ESAs), might play a role in the development of a form of leukemia when they are used to treat people with a rare blood disorder known as myelofibrosis. This is just the latest bit of bad news related to Aranesp, Epogen and Procrit this year, which have been the subject of an ongoing Food & Drug Administration (FDA) safety review. Just last month, the FDA strengthened safety warnings on the drugs amid concerns that they increase the risk of death, heart attack, stroke and the progression of other cancers.
Myelofibrosis is a bone marrow disorder that interrupts the body's normal production of blood cells, leading to severe anemia and enlargement of the spleen. While myleofibrosis can progress to leukemia on its own, researchers at the Mayo Clinic found that patients treated with ESAs were far more likely to develop the blood cancer. They examined the records of 311 patients with primary myelofibrosis from 1976 to 2006 to see what factors led some of them to advance to acute leukemia. They found that patients in the study who took ESAs tended to be sicker, and were more likely to develop leukemia.
ESAs like Aranesp, Epogen and Procrit treat anemia in patients with kidney disease or certain cancers by boosting red blood cells. However, several studies have linked the anemia drugs to cardiovascular problems and deaths. They have also been tied to worsening tumors when used in cancer patients. A year ago, the FDA ordered that a “black box” warning regarding cardiovascular problems and other safety issues posed by the drugs be included on their labels. In March, the FDA added a black box warning to the drugs’ labels cautioning doctors that the medications should be administered at the lowest dose possible in order to bring red blood cell counts to the lowest level necessary to avoid transfusions. Last month, that black box warning was modified to include stronger language and more specific dosing information.
Last week, Amgen, the manufacturer of all three drugs, said a study done on breast cancer patients treated with the Aranesp showed that it offered them little help, and also placed them at a higher risk of death. Amgen said it was considering further warnings for the drugs. Aranesp and Epogen are marketed by Amgen, while Procrit is sold by Johnson & Johnson under a licensing agreement with Amgen.
Following the release of the Aranesp breast cancer study, the FDA announced that it would be holding yet another advisory panel meeting in March to discuss the safety of Aranesp, Epogen and Procrit. The March meeting will be the fourth time the FDA has held such a meeting to discuss ESAs. Following one of these meetings in May, the Centers for Medicare and Medicaid Services changed the reimbursement policy for Aranesp and other ESAs. Now doctors will only be paid for using a low dose of the drug.
Since safety concerns over Aranesp, Epogen and Procrit first surfaces, Amgen has lost nearly $19 billion in market value.