The Impact of the Risk Evaluation Mitigation Strategy for Erythropoiesis-Stimulating Agents on Their Use and the Incidence of Stroke in Medicare Subjects with Chemotherapy-Induced Anemia with Lung and/or Breast Cancers.

ABSTRACT

Erythropoiesis-stimulating agents (ESAs), found to be effective in reducing anemia in chemotherapy-treated cancer patients, also are associated with an increased risk of cardiovascular events, including stroke. In an attempt to mitigate the risk, the Food and Drug Administration implemented a Risk Evaluation Mitigation Strategy (REMS) in February 2010. The purpose of this study is to evaluate change over time in the incidence of stroke among these patients before and after implementation of REMS. A retrospective data analysis using the Medicare 5% Sample Dataset, 2008-2011, was performed. Patients had to be 65 years of age or older at the start of at least 1 year of continuous enrollment and to have lung and/or breast cancers along with chemotherapy-induced anemia (CIA) in both pre-REMS and post-REMS periods (1Q2008 through 4Q2009 and 1Q2010 through 4Q2011, respectively). Logistic regression was used to evaluate differences in proportions of patients who received ESAs and experienced a stroke pre and post REMS. The pre-REMS cohort included 1252 eligible patients prescribed ESAs; the post-REMS cohort included 949 patients. No statistically significant change in stroke incidence was observed post REMS among patients with CIA who received ESAs. There was a 29.5% decrease in ESA use in patients with lung cancer and a 27.8% decrease in patients with breast cancer. Both were statistically significant. Results adjusted for baseline characteristics and comorbid conditions were similar. There was a statistically significant decrease in ESA use in patients with breast and/or lung cancers post REMS; no statistically significant reduction in the incidence of stroke was observed regardless of cancer type.