Subjects: R and D
Drugs used to reverse anemia in cancer and kidney failure patients are largely ineffective and markedly increase the risk of blood clots, according to a study by scientists at Columbia University Medical Center.
To reach this conclusion, Dawn Hershman and colleagues studied use of the so-called erythropoiesis stimulating agents (ESAs) in more than 50,000 patients that had been diagnosed with cancer.
In these patients, ESAs did not reduce blood transfusion requirements caused by chemotherapy, but they did jack up the risk of deep venous thrombosis and pulmonary embolism.
Hershman’s study population included patients that were at least 65 years of age and had been diagnosed with cancers of the breast, colon and lung. ESAs are used frequently in such patients as adjuncts to chemotherapy.
Survival was not impacted by the ESAs.
The number of patients receiving ESAs jumped 10-fold from 1991 through 2002. By that time, nearly half of all cancer patients were receiving them.
“This analysis confirms the association between ESAs and venous thromboembolism, which was observed in previous meta-analysis,” Hershman told BurillReport. “This data is from community practice – real-life clinical settings – where you see things that wouldn’t necessarily show-up in a short-term, 12-week study.”
Leading ESAs include Amgen’s Aranesp and Epogen, and Johnson & Johnson’s Procrit. Sales of these drugs topped $10 billion in 2006 in the US alone.
The meta-analysis mentioned above prompted the FDA to issue a black-box warning regarding the potential for tumor promotion, venous thromboembolism and decreased survival with ESAs. The warning suggested that ESAs should be used only for specific tumors and only when hemoglobin levels dropped below certain levels.
The write-up appears in the Journal of the National Cancer Institute.