On December 11, 2007, research presented by the Mayo Clinic pertaining to their review of the records of 311 patients with primary myelofibrosis revealed a link between anemia drugs and leukemia risks.

Primary myelofibrosis is a disorder of the bone marrow in which the marrow is replaced by fibrous (scar) tissue. Patients with primary myelofibrosis usually experience symptoms of fatigue, and take anemia drugs to help combat the condition by stimulating growth of oxygen-carrying red blood cells.

Anemia drugs, including Amgen’s Aranesp and Epogen, and Johnson and Johnson’s Procrit, were found to elevate the risk of leukemia in patients with primary myelofibrosis. The Mayo Clinic’s research of 311 patients with primary myelofibrosis over a 30 year period found 27 patients who had developed leukemia.

The study also found that patients who took the modified form of testosterone, danazol (formerly marketed as Danocrine), seem to have a higher risk of developing leukemia as well.

Although research findings still need to be confirmed in a trial focusing specifically on anemia drug risk, the study’s lead investigator warned that “[t]reatment decisions regarding the use of anemia drugs in patients with primary myelofibrosis should carefully be evaluated.”

Source: “Mayo Clinic Study Links Anemia Drugs to Leukemia Risk,” Bloomberg News, December 11, 2007.