Recombinant human erythropoietin in cancer-related anemia. Review of clinical evidence.

The clinical development of recombinant human erythropoietin (rHuEPO) has had a remarkable impact on the clinical practice of oncology. A decade ago, randomized, placebo-controlled trials in anemic cancer patients demonstrated that rHuEPO resulted in an improvement in hemoglobin and hematocrit, a reduction in transfusion requirements, and improvement in quality-of-life (QOL) end points. Based on these trials, recombinant erythropoietin was approved for the treatment of anemia in patients with nonmyeloid malignancies in whom the anemia was caused by the effect of chemotherapy. The clinical indication was to decrease the needfor transfusion in patients for whom anemia was not due to other reversible causes. Despite this broad indication, the incorporation of rHuEPO in clinical practice was limited because of a variety of factors, including physician perception that mild-to-moderate anemia in the cancer patient was generally asymptomatic and did not warrant intervention. Subsequently, three large open-label, prospective trials of recombinant erythropoietin were performed in the community setting in anemic cancer chemotherapy patients. All three trials replicated the results of the original randomized study, but with a much larger database of more than 7,000 patients. Importantly, these trials were able to define the major impact of hemoglobin level on quality of life. Patients on these trials who improved their hemoglobin > 2 g/dL or achieved a hemoglobin > or = 12 g/ dL had the greatest improvement in symptoms of energy, activities of daily living, and overall quality of life. Furthermore, a once-per-week dosing schedule was found to be comparable to three-times-weekly administration of rHuEPO. A European randomized, placebo-controlled trial confirmed these QOL results, and a meta-analysis of other randomized clinical trials firmly supports the role of erythropoietin therapy in improving hemoglobin levels and reducing transfusion requirements. Based on this aggregate of data, the use of erythropoietin in the treatment of mild-to-moderate anemia has become a standard of care. These studies have also expanded our understanding of the problem of fatigue and the study of interventions that can improve quality of life for cancer patients.