Erythropoetin stimulating agents (ESAs) promote the production of red blood cells by red blood stem cells. They are commonly utilized to reduce the frequency of transfusions in cancer patients. In recent months, significant concerns have been raised about ESAs, questioning whether or not the risks outweigh the benefits. ESAs include drugs such as Procrit/Eprex (epoetin alfa) and Arenesp (darbepoetin alfa). Recently, a Food & Drug Administration (FDA) advisory committee met to discuss these concerns and vote on changes regarding the ESA’s.
Concern one: Early studies have shown that ESAs may stimulate specific cancers to grow more quickly or recur more frequently. These studies have included small cell lung cancer, non-small cell lung cancer, breast cancer, head and neck cancer, lymphoid cancers, and cervical cancers. With the exclusion of small cell lung cancer, all of the above listed cancers showed a worsening of disease associated with the use of ESAs. Potential adverse side-effects have not been examined for many other cancers including sarcomas.
Concern two: According to a recent study, ESAs increase the risk of venous thromboembolism (blood clots in the legs or lungs) and mortality1. The increased risk of thromboembolism does not completely explain the increased rate of mortality in this study.
Concern three: ESAs are frequently used off-label to improve the quality of life of cancer patients. This includes the use of ESAs to reduce cancer-associated fatigue and to increase levels of hemoglobin to as high as 13 or 14 grams as opposed to 12 grams, the level at which anemia-related symptoms are reduced2.
The vote by the FDA advisory panel recommended the following:
- Chemotherapy-induced anemia should be an indication for the use of ESAs.
- The use of ESAs should not be limited to those cancers such small cell lung cancer which has been shown to be unaffected by ESAs.
- ESAs should not be used in patients with head and neck cancer or metastatic breast cancer due to the potential increased progression.
- If a patient has a potentially curable cancer, ESAs should not be used.
- A restricted distribution system for ESAs should not be mandated.
- No recommendation was made on the hemoglobin level at which initiation ESA therapy should be considered.
- For GIST patients, this means that ESAs are still available for use. Based on these recommendations, coverage of ESAs by Medicare and private insurance companies should not be affected. The effect of ESAs on GIST progression rates has not been studied. Patients and caregivers need to be aware of the potential risks and benefits when deciding whether to initiate ESA therapy.
1. Barbara LM. Erythropoiesis Stimulating Agents: Benefits/Risks in Supportive Care of Cancer. Current Oncology; Going Beyond Efficacy. 2007.
2. Bennett CL, Silver SM, Djulbegovic B et al. Venous Thromboembolism and Mortality Associated With Recombinant Erythropoietin and Darbepoetin Administration for the Treatment of Cancer- Associated Anemia. JAMA. 2008;299:914-924