Anemia management with erythropoietic stimulating therapies (ESTs) in patients (pts) with gastrointestinal (GI) malignancies: Results from a prospective observational study

Abstract

19614 Background: Chemotherapy-induced anemia is a common problem for pts with GI malignancies. To assess dosing patterns and outcomes in GI malignancy pts treated with ESTs (epoetin alfa (EPO) and darbepoetin alfa (DARB), a subset analysis of an ongoing registry was conducted. Methods: Data drawn between1/04 and 10/06 from 41 U.S. oncology clinics from the Dosing and Outcomes Study of Erythropoietic Stimulating Therapies (D.O.S.E.) registry were assessed. Pts were included in this analysis if they were diagnosed with a GI malignancy (colon, rectal, gastric, esophageal, or pancreatic), = 18 years, and received = 2 doses of either EPO or DARB. Outcomes assessed included mean baseline (BL) characteristics, transfusion utilization, hemoglobin (Hb) at Weeks 4, 8, and 12 after initiation of EPO or DARB, and cumulative EST doses with associated cost (based on 9/2006 wholesale acquisition cost). Results: 186 pts (82 EPO, 104 DARB) were identified. BL characteristics were similar between treatment groups: age 64 years, 45% women, and Hb 10.5g/dL. Both groups had a similar treatment duration (7 weeks) and number of Hb determinations (7.6); however, the DARB group had significantly more office visits (EPO 7, DARB 9.8, p=.0006). The proportion of pts transfused from Week 5 to end of study and number of units transfused/pt were similar between both groups. Hb values were similar at Weeks 4 (11.1 g/dL), 8 (11.1 g/dL), and 12 (11.0 g/dL). The mean administered dose per injection was 42,143 Units for EPO and 225 mcg for DARB. Mean cumulative administered dose during the treatment episode was 296,476 Units for EPO and 1,131 mcg for DARB, resulting in a dose ratio of 262:1 (Units EPO:mcg DARB). Overall EST cost was significantly lower in the EPO group compared to the DARB group (EPO $3,608, DARB $5,028, p=.0024). Conclusions: Similar hematological outcomes for EPO- and DARB-treated pts with GI malignancies were observed. Based on observed dosing patterns and cumulative EST utilization from this prospective observational study, EST costs were 28% lower in the EPO group than the DARB group. The observed dose ratio is consistent with previously reported clinical studies. No significant financial relationships to disclose.