Controversial Anemia Drug Doesn't Cut Need for Transfusions

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In May, a U.S. Food and Drug Administration advisory panel called for new warnings and additional safety studies on epoetin alfa and other anemia drugs, largely due to dangerous side effects such as the risk of blood clots, strokes, heart attacks and death.

In March, the FDA issued stronger label warnings for the popular drugs, which are also used for patients with chronic kidney failure and cancer.

And on Sept. 11, an FDA advisory panel is scheduled to meet to discuss new evidence on the safety of the drugs, although the panel will be looking at a different group of patients than those involved in this latest study.

For the study, the researchers enrolled 1,460 medical, surgical or trauma patients from 48 to 96 hours after admission to the intensive care unit. Each patient received either epoetin alfa or a placebo weekly for a maximum of three weeks, and all patients were followed for 140 days.

There was no difference in the number of patients who received a transfusion in the placebo or epoetin alfa group, or the number of red-cell units transfused, probably a result of changes in transfusion practice, Corwin said.

Side effects in general were comparable between the two groups, although clotting was higher in the epoetin alfa group. "That shouldn't be forgotten," Corwin said.

However, the concentration of hemoglobin, a protein in red blood cells that carries oxygen to tissues, did increase more in the epoetin alfa group than in the placebo group.

In addition, the mortality rate in patients receiving epoetin alfa was lower than among those receiving a placebo. That effect was most pronounced in trauma patients. "More research is needed to look at the trauma patients and the mechanism for epoetin alfa effect on mortality," Corwin said.

The beneficial mechanism appears to be something other than the drug's ability to enhance red blood cell formation.

"There's some data in animal studies and small clinical studies suggesting that epoetin alfa has a lot of other effects in addition to making blood cells, and we think it's one of these other mechanisms that is causing the mortality benefit," Corwin said.

"There is a whole range of other areas where epoetin alfa may have potential benefits through these other mechanisms," he continued. "This opens up a whole new area of study. There may be benefits in terms of function after strokes or head injury. There needs to be additional work to sort out the mechanisms responsible for this benefit."

More information

To learn more about these anemia drugs, visit the U.S. Food and Drug Administration.