Researchers in The Cochrane Collaboration conducted a review of the effect of epoetin and darbepoetin for people with cancer. After searching for all relevant studies, they found 91 studies with up to 20,102 people. Their findings are summarized below:
What the research says:
In people with cancer-related anaemia:
- It is not clear whether epoetin and darbepoetin improve quality of life, by making you feel less tired
When you have cancer, you often also have anaemia. Anemia means having lower than normal red blood cells in your blood. This might become even worse with cancer treatment such as chemotherapy and it is measured by the amount of haemoglobin in your red blood cells. As haemoglobin is responsible for carrying oxygen throughout your body, when you have anaemia you might experience symptoms such as extreme tiredness, shortness of breath, dizziness and chest pain. In order to treat anaemia, doctors often use red blood cell transfusions. Transfusions improve the symptoms of anaemia very quickly; however, they can have some infrequent complications like allergic reactions or transmission of infectious diseases.
Epoetin and darbepoetin belong to a group of medications called 'Erythropoiesis Stimulating Agents'. Erythropoietin is the name of a hormone produced mainly in the kidney, which takes part in the production of red blood cells. Epoetin and darbepoetin work in a similar way to this hormone to increase the number of red blood cells and treat anaemia. Epoetin and darbepoetin are not used as anti-cancer therapy but as supportive treatment to treat anaemia caused by cancer or anticancer therapy. These drugs are marketed as Epogen®, Procrit®, (Eprex®), Recormon®, and Aranesp® and are given subcutaneously.
What happens to people with cancer related anaemia who take epoetin or darbepoetin:
- Twenty-five out of 100 persons receiving epoetin or darbepoetin had to undergo red blood cell transfusions, compared to 39 out of 100 persons not receiving epoetin or darbepoetin.
- More people who received epoetin or darbepoetin died during and up to 30 days after the end of study compared with people who took placebo or underwent standard treatment. The increased risk for people taking epoetin or darbepoetin was 17%. One hundred and fourteen out of 1,000 persons receiving epoetin or darbepoetin died, compared with 98 out of 1,000 persons not receiving epoetin or darbepoetin. We could not identify particular characteristics of people or treatment strategies that increased or decreased the risk for dying.
- People receiving epoetin or darbepoetin rated their fatigue symptoms to be an average of 2.08 points improved on a scale of 0-52 points after 3-4 months, compared with people taking placebo or having standard treatment. This improvement, however, is less than the 3.0 point increase which is considered to be the minimum required for the patient to feel a difference in his experience of fatigue-related symptoms using this scale.
- People taking epoetin or darbepoetin rated their fatigue and anaemia symptoms had to be an average of 6.14 points improved after three to four months, on a scale of 0-80 points. This improvement is considered to reflect a positive change in the way patients experience their fatigue and anaemia related symptoms, as it is more than four to five points of increase which is the minimum required for this scale.
- Seven people out of 100 who took epoetin or darbepoetin suffered a thromboembolic event such as stroke and myocardial infarction compared with five people out of 100 who did not receive epoetin or darbepoetin.
- Six out of 100 people receiving epoetin or darbepoetin developed high blood pressure compared with four out of 100 people who took placebo or had standard care.