Darbepoetin alfa (Aranesp(r), DA), a unique erythropoietic molecule with 3-fold longer half-life than epoetin alfa (EPO), is indicated for treatment of chemotherapy-induced anemia (CIA). OBJECTIVE: To determine the most common initial dosing regimens for DA and EPO in clinical practice and evaluate their effectiveness after four weeks of therapy. METHODS: In order to determine which initial regimens are most commonly used in practice as well as their effectiveness, we conducted a chart review within Tennessee Oncology. Tennessee Oncology, a major provider of cancer care in the Nashville area, has collected extensive data on EPO and DA use as part of their quality assurance process. DA patients switched from EPO were not eligible for the analysis. Mean hemoglobin changes were not adjusted for transfusions. RESULTS: Of 408 patients treated with an erythropoetic agent, 196 received DA and 212 received EPO. The majority of EPO patients (86.3%) had an initial dosing schedule of 40,000 U QW (EPO40KQW). The majority of DA patients received a fixed dose. Of 196 DA patients, 97 (49.5%) received 100 mcg QW (DA100QW) and 70 (35.7%) received 200 mcg Q2W (DA200Q2W). Hemoglobin (hgb) values were collected at baseline and beginning of week 5. Mean baseline hgb (g/dL) [95% CL] for the DA100QW, DA200Q2W and EPO40KQW groups were 10.2 [± 0.15], 9.9 [± 0.18], and 9.7 [± 0.14], respectively. Mean changes in hgb (g/dL) [95%CL] after 4 weeks of therapy for the DA100QW, DA200Q2W, and EPO40KQW group were 0.9 [± 0.24], 1.1 [± 0.29], and 0.8 [± 0.22], respectively. The median for each group was very similar to the corresponding mean. CONCLUSIONS: These results establish that 200 mcg Q2W DA maintained dose efficiency when compared to 100 mcg QW and was at least as effective as 40,000 U QW of EPO after 4 weeks therapy in patients with CIA.