Hematologic Outcomes and Erythropoiesis-Stimulating Therapy Costs in Epoetin Alfa (EPO)- and Darbepoetin Alfa (DARB)-Treated Cancer Patients: Results of the Dosing and Outcomes Study of Erythropoiesis-Stimulating Therapies (D.O.S.E. Registry).

Background: National Comprehensive Cancer Network (NCCN) anemia treatment guidelines recommend maintenance of hemoglobin (Hb) levels between 11–12 g/dL. To investigate hematologic outcomes and costs of erythropoiesis-stimulating therapies (ESTs), data were analyzed from the D.O.S.E. Registry, an ongoing, prospective registry collecting data on real-world practice patterns and outcomes in cancer patients treated with ESTs.

Methods: Data come from U.S. hospital and community-based outpatient practices assessed from 1/04–6/06. Adult patients with a non-myeloid malignancy and receipt of at least 2 doses of either EPO or DARB were included. Outcomes assessed included mean treatment duration; mean cumulative dose; maintenance of Hb between 11–12g/dL; mean Hb level at Weeks 4, 8, 12, and 16; and proportion of patients receiving blood transfusions. EST costs were based on May 2006 wholesale acquisition costs.

Results: 861 patients (312 EPO, 549 DARB) from 45 sites were identified. Mean baseline characteristics were similar between the groups (entire cohort: age 62.4 years, 64.1% women, weight 75.9 kg, and Hb 10.4 g/dL) with the exception of a significantly higher proportion of patients receiving iron supplementation in the DARB-treated group (EPO 18%, DARB 29%, p<0.01). The most common malignancies were breast, lung and gastrointestinal. Both groups had similar mean treatment duration (approximately 8 weeks), number of Hb assessments (approximately 8) and proportion of patients requiring blood transfusion following the initial four weeks of treatment (EPO 9%, DARB 11%, p=0.32). The mean cumulative doses for EPO (373,827 Units) and DARB (1,185 mcg) were associated with EST drug costs of $4,550 for EPO and $5,267 for DARB, (p<0.001). Mean Hb level was ≥ 11 g/dL at all post-baseline time points in the EPO-treated group, however <11 g/dL in the DARB-treated group at Weeks 12 and 16. Mean Hb level was significantly higher in the EPO-treated group at Week 12 (EPO 11.3 g/dL, DARB 10.8 g/dL, p=0.03).

Conclusions: In this prospective observational study, EPO-treated patients achieved and maintained NCCN target Hb levels at all timepoints. These findings also showed EST cost to be 16% higher in the DARB-treated group than in the EPO-treated group.