Health and Medicine Media

Drugs to combat anemia associated with chemotherapy and chronic kidney disease increase risk of venous thromboembolism.

The controversy over Procrit and Aranesp, two drugs used to combat anemia associated with chemotherapy and chronic kidney disease, continues to increase, because new research indicates that increase the risk of venous thromboembolism is the formation of potentially fatal blood clots .

Recent studies have linked these drugs, called erythropoietic stimulating agents (ESA), with an increased risk of death, stroke, and new cancers.

Dr. Dawn Hershman, principal investigator of the study noted that “from the beginning, there was concern that these drugs cause some side effects, but initial studies found no risk of thrombosis.” However, a longer-term study, was more informative and confirmed that these agents may increase to twice the risk of thrombosis, he said.

Procrit and Aranesp drugs hit the market in the mid 90s, and it is estimated that by 2002, 50 percent of patients receiving chemotherapy took them.

For the study, Hershman team collected data from more than 56.210 patients with cancer treated with chemotherapy from 1991 to 2002. The researchers found that 14.3 percent of patients who received ESA developed venous thromboembolism (deep vein thrombosis or pulmonary embolism) compared with 9.8 percent of those who did not receive ESA.

Taking into account the problems raised by previous studies, the Food and Drug Administration (FDA) of USA. UU. demanded in 2007 placing a black box label for ESAs in order to warn of the risk of venous thromboembolism, tumor growth and death. The warning suggested restricting the use of ESAs in specific tumor types, and addressed issues such as dose, duration and target hemoglobin levels.

For his part, Dr. J. Leonard Lichtenfeld, deputy chief medical officer American Cancer Society, said, “This study is one of a list that suggests the value of the ESA is lower than expected and that its side effects are greater than anticipated.” However advises that “if you are treated with these drugs, take them with caution and full knowledge, discuss with your doctor about the need to use these drugs and the potential complications that might experience.