FRIDAY JAN 4, 2008 (Foodconsumer.org) - The U.S. Food and Drug Administration (FDA) announced Thursday January 3 that it will be reviewing new data on anemia drugs called erythropoiesis-stimulating agents, or ESAs.

These new data provided by Amgen and Johnson & Johnson indicate additional health risks posed by these drugs to cancer patients taking them. FDA Deputy Commissioner Janet Woodcock indicated further action may be taken by the agency following the review of these studies.

FDA revealed Amgen had provided data on new studies on November 30 and December 4 last year.

The first study called PREPARE involved 733 women with breast cancer or advanced cervical cancer. All women had received chemotherapy prior to surgery for their cancer. The women were randomly assigned to take an ESA called Aranesp or a placebo.

After three years, 14 percent of the women in Aranesp group died as compared to 9.8 percent in the group of women who did not receive the drug. Additionally the growth of cancer was also faster in the Aranesp group.

In the second study handed over to the FDA on December 4, patients were given Procrit to hold their hemoglobin levels above 12 g/dL. Another group received blood transfusions as needed. The study was conducted by National Cancer Institute’s Gynecologic Oncology Group. All patients in the study were receiving chemotherapy and radiation for advanced cervical cancer.

The study showed 66 percent of patients who did not receive Procrit were alive or free from cancer progression after three years as compared to 58 percent of patients in the Procrit group.

ESAs are drugs that are synthetically engineered from a natural protein elaborated in the kidney. This protein called erythropoietin is responsible for stimulating the growth of new red blood cells in the bone marrow. The drugs are approved to treat anemia in cancer patients and patients with chronic kidney failure.

This is not the first time that ESAs have come under the FDA scanner. In 1997, 2004 and 2005, the agency has revised labeling information on these drugs. Last year, the FDA added new black box warnings to these drugs.

In 2006 a study in the New England Journal of Medicine had found that kidney disease patients taking Procrit had a higher risk of heart attacks as compared to those who did not take the drug.

"This new information further underscores the safety concerns regarding the use of ESAs in patients with cancer, which FDA addressed in previous communications," said Dr. Janet Woodcock, the FDA's deputy commissioner for scientific and medical programs.

The FDA has asked doctors to review and discuss with their patients the risks and benefits of ESAs mentioned in the product label of the drugs prescribed to them.

For more information on Amgen, visit www.en.wikipedia.org/wiki/Amgen