Epoetin alfa-epbx: a new entrant into a crowded market. a historical review of the role of erythropoietin stimulating agents and the development of the first epoetin biosimilar in the United States.

: Erythropoietin stimulating agents (ESAs) have been established both to correct anemia and provide the clinical benefits of increased exercise capacity, reduced transfusion requirements, and improved quality of life. An increase in physician and patient adoption of biosimilars, as well as changes to healthcare reimbursement policies, have driven market competitors to innovate and expand the range of biosimilar products. While erythropoietin biosimilars have been approved by the EMA since 2007, the FDA's approval of epoetin alfa-epbx in 2018 marks the first erythropoietin biosimilar approved in the United States. : In this article, we critically review the biology, clinical use, manufacturing, safety, and efficacy of ESAs and erythropoietin biosimilars. We then review the regulatory framework and potential impact on healthcare costs offered by erythropoietin biosimilars. : Due to the complex nature of manufacturing large-molecule biologics, it is important to recognize the challenges to quality assurance and overall safety posed by the introduction of biosimilars, which undergo much more limited clinical testing than their reference biologic product before coming to market. With many biologic therapies nearing patent expiration, biosimilars will become increasingly common in clinical practice. Ensuring patient safety with these products will require increased post-marketing surveillance and awareness from prescribers.