Retrospective evaluation of response to epoetin alfa in patients with hematologic disorders

Study objectives. To evaluate the impact of epoetin therapy in patients with hematologic malignancies and myelodysplasias (MDS) on hemoglobin (Hb) response, transfusion requirements and to evaluate factors, such as endogenous erythropoietin levels and serum creatinine that predict response to epoetin therapy. Methods. Inpatient and outpatient pharmacy records were analyzed to identify patients with hematological disorders receiving epoetin therapy. No patients were receiving treatment with chemotherapy. Baseline and final Hb levels and transfusion requirements were analysed and factors predicting response to epoetin were evaluated. Results. The mean baseline Hb increased from 9.9 g/dL (± 1.09) to 12.1 g/dL (± 1.84) for a mean Hb increase of 2.81 g/dL (P = 3.3. × 10 ^-12) and 29 of 35 patients experienced clinical benefit to the epoetin. Overall, the mean transfusion burden fell from 0.94 units of packed red blood cells per month to 0.38 units/month (P = 0.034 by paired t-test) at the end of the evaluation period. When measured by percentage of patients requiring transfusions, 42% had a transfusion the month prior to receiving epoetin, where as only 11% required transfusions while receiving epoetin. The mean endogenous erythropoietin was 51.2 IU/L (n = 25) in the patients who responded to epoetin and 129 IU/L (n = 2) in the nonresponder group (P = 0.012), although two individuals with endogenous erythropoetin levels greater than 200 IU/L responded to epoetin. Thirteen of 14 patients with MDS in this series responded to epoetin, and the only patient not responding was progressing to AML. Conclusions. Epoetin is effective in improving anemia in patient's with hematological malignancies not receiving chemotherapy. While the numbers in this retrospective evaluation are small, it appears that patients with low endogenous erythropoetin levels and high serum creatinine are most likely to respond; a relationship that could be explored in future larger and prospective evaluations.