Dosing Patterns of Erythropoietic Agents and Their Association with Provider Visits in Patients with Cancer and Anemia.

Background: Understanding current dosing patterns of epoetin alfa (EPO) and darbepoetin alfa (DARB) in clinical practice and their association with provider visits is important to optimize patient management and assess the total costs of anemia care.

Objective: To assess dosing patterns of erythropoietic agents and the frequencies of provider visits in patients with cancer and anemia.

Methods: A cross-sectional study of adults with solid tumor cancers and anemia is on going. 500 planned participants are being recruited through 50 oncologists’ offices across the U.S. Information is collected via a self-administered questionnaire that is divided into two parts. The first, completed by the provider, captures clinical information; the second, completed by patients, records their knowledge, experience and preferences regarding anemia and its treatments, including resource use, quality of life and productivity. This preliminary analysis focuses on the provider-reported dosing section (most recent dosing of the erythropoietic agent) and patient-reported resource utilization section (past month recall of visits to providers).

Results: 276 provider/patient-matched questionnaires have been received. Of these, there were 78 EPO, 172 DARB, 21 Untreated and 5 patients who had received both agents within the past month. 96% of patients were receiving chemotherapy concurrently. The majority of EPO patients were dosed weekly (QW) followed by every 2 week dosing (Q2W) while most DARB patients were dosed Q2W weeks followed by QW dosing (EPO: QW 90%, Q2W 10%; DARB: QW 26%, Q2W 63%, Other 10%). Mean weekly doses for each agent were: EPO 37,574 Units/week; DARB 140 mcg/week; corresponding to an EPO:DARB dose ratio of 267:1. All patients reported a mean of 7.6 visits to providers in the past month, with similar results among the three patient groups (EPO: 8.8, DARB: 7.2, Untreated: 5.9; p=0.316). Most patients described the number of visits during the past month as “typical” (64% overall, range of 60–66% among patient groups; p=0.801). Among patients receiving an erythropoietic agent, the mean number of past monthly visits did not differ by frequency of administration (QW: 8.7, Q2W: 7.4, Other: 4.9; p=0.064).

Conclusion: Based on provider and patient-reported data, dosing patterns showed most EPO patients are dosed QW while most DARB patients are dosed Q2W. The EPO:DARB dose ratio was found to be 267:1 which is consistent with other observational studies using claims data and chart reviews (