Findings from an interim analysis of a new study comparing the hemoglobin response rates of Epoetin alfa and darbepoetin alfa in the treatment of chemotherapy-related anemia were published in the November 15, 2004 issue of the Medical Journal 'Blood' as part of the American Society of Hematology 46th Annual Meeting and Exposition. Both therapies are indicated to treat anemia by increasing hemoglobin levels and reducing the need for blood transfusions.
These interim results were from a randomized, open-label, multi-center study. The endpoints of this trial were hemoglobin response, transfusions and safety in adult patients with chemotherapy-related anemia. Hemoglobin is the part of red blood cells that carries oxygen, which acts like fuel, to tissues of the body.
The study was designed to demonstrate statistical superiority in the primary endpoint, which was the hemoglobin response rate within the first four weeks of treatment. The results indicate that hemoglobin levels increased more than 1 g/dL from baseline within the first four weeks of treatment for 47 percent of patients treated with Epoetin alfa, compared to 33 percent of patients treated with darbepoetin alfa, a statistically significant difference. Average hemoglobin increases after four weeks were 0.7 g/dL for patients treated with Epoetin alfa and 0.3 g/dL for patients treated with darbepoetin alfa. Further increases in average hemoglobin for Epoetin alfa and darbepoetin alfa, respectively, were 1.0 g/dL and 0.5 g/dL after eight weeks and 1.3 g/dL and 0.7 g/dL after 12 and 16 weeks.
Three hundred and fifty-eight adult cancer patients with chemotherapy- related anemia were enrolled in this trial. The most common cancer types in the study group were breast, lung and colorectal. All patients had baseline hemoglobin levels of 11 g/dL or less, were scheduled to receive chemotherapy for 12 weeks or more, and had no anemia therapy for the past three months. Patients were grouped based on the type of chemotherapy with which they were being treated (platinum vs. non-platinum) and then randomized to receive either Epoetin alfa at a dosage of 40,000 units once a week or 200 units of darbepoetin alfa once every two weeks by subcutaneous injection. Both groups were treated for up to 16 weeks.
Additionally, the study results show 13 percent of patients treated with Epoetin alfa received red blood cell or whole blood transfusions after 28 days of therapy, compared to 17 percent of patients treated with darbepoetin alfa. However, the frequency of transfusions, a secondary endpoint, is not statistically significant between the treatment groups in this interim data analysis. Both agents demonstrate similar safety profiles.
The study was supported by Ortho Biotech Products, L.P., marketers of Procrit (Epoetin alfa).
Anemia is a side effect experienced by more than 71 percent of cancer patients undergoing chemotherapy. This potentially life-threatening condition occurs when the body does not have enough red blood cells, which carry oxygen. Oxygen acts like fuel for the body, providing energy for muscles and organs to work. Common symptoms include extreme fatigue, shortness of breath, dizziness, decreased ability to concentrate and sleeplessness.
Procrit (Epoetin alfa) stimulates red blood cell production and has an amino acid sequence identical to the body's naturally occurring erythropoietin, which is produced in healthy kidneys. When more red blood cells are produced, more oxygen is carried through the body, which may increase energy levels. It has been used in more than two million people across four indications and is indicated to treat chemotherapy-related anemia in patients with most types of cancer.
Procrit is available by prescription only and is injected by doctors or nurses. Procrit is not for patients with uncontrolled high blood pressure. High blood pressure has been noted rarely in cancer patients treated with Procrit, and blood pressure should be monitored carefully. Drugs like Procrit may increase the risk of blood clots. In studies, the most common side effects included fever, diarrhea, nausea, vomiting, edema, shortness of breath, tingling and upper respiratory infection.