Outcomes of erythropoiesis-stimulating agents in cancer patients with chemotherapy-induced anemia

PURPOSE: To assess the clinical and economic outcomes among patients with chemotherapy-induced anemia (CIA) treated with United States Food and Drug Administration-approved fixed dosing regimens of erythropoiesis-stimulating agents (ESA). METHODS: Data were employed from the Dosing and Outcomes Study of Erythropoiesis-Stimulating Therapies (DOSE) registry to evaluate CIA patients who were initiated on either epoetin alfa (EPO) 40,000 Units (U) or darbepoetin alfa (DARB) 500 micrograms (mcg) between January 1, 2006 and May 8, 2009. Study measurements included ESA treatment dose and dose ratio, changes in hemoglobin (Hb) levels from baseline, and cumulative ESA costs. RESULTS: Five hundred forty patients treated in 44 clinical centers were evaluated, of which 420 were initiated on EPO 40,000 U and 120 were initiated on DARB 500 mcg. Both cohorts had similar baseline characteristics, although EPO patients were less likely than DARB patients to have received iron supplementation before ESA initiation (11.4% EPO vs. 20.0% DARB, p = 0.015). The EPO-to-DARB dose ratio based on cumulative ESA dose was 169:1 (U EPO: mcg DARB). EPO patients showed statistically greater Hb improvement compared to DARB patients, and compared to EPO patients, a greater proportion of DARB patients required a blood transfusion (13.9% EPO vs. 22.5% DARB, p = 0.026). Mean cumulative ESA cost was significantly lower for EPO patients than DARB patients ($4,261 EPO vs. $8,643 DARB, p < 0.0001). CONCLUSIONS: These findings reported that patients with CIA achieved more favorable clinical and economic outcomes if initiated with EPO 40,000 U vs. DARB 500 mcg.