Amgen adds anaemia drug warning
after the Food and Drug Administration (FDA) and healthcare
professionals were warned of the anaemia drug Aranesp, after
studies on similar drugs showed higher doses can cause blood clots
and even death.
Researchers reported an increased incidence of thrombotic events had been observed in patients treated with erythropoietic agents. In patients with cancer who received Aranesp, which is used to treat chemotherapy-induced anaemia in patients suffering from cancer, clotting occurred more frequently than in placebo controls.
The action by Amgen to add a warning to Aranesp comes after an FDA panel called for more study of the risks of the anaemia drugs, including faster tumour growth and more blood clots. Some researchers had thought elevating haemoglobin might increase the effectiveness of chemotherapy and radiation to fight cancer.
In the randomised controlled study with another erythropoietic product in 939 women with metastatic breast cancer receiving chemotherapy, patients received either weekly Epoetin alfa or placebo for up to a year. This study was designed to prevent anaemia (maintain hemoglobin levels between 12 and 14 g/dL).
Treatment with Epoetin alfa was associated with a higher rate of fatal thrombotic events in the first 4 months of the study. Mortality at one year, the primary endpoint of the study, was higher for the Epoetin alfa group
The studies permitted or required dosing to achieve haemoglobin levels of greater than 12 grams per decilitre.
Aranesp is a growth factor that primarily stimulates RBC production. Erythropoietin receptors are also found on the surfaces of normal, non-hematopoietic tissues and some malignant cell lines and tumor biopsy specimens. However, it is not known if these receptors are functional. The possibility that Aranesp can act as a growth factor for any tumour type, particularly myeloid malignancies, has not been evaluated
