Biosimilars are biological drug products that are highly similar to reference products in analytic features, pharmacokinetics and pharmacodynamics, immunogenicity, safety and efficacy. Biosimilar epoetin received US Food and Drug Administration (FDA) approval in 2018 [1]. The manufacturer received an FDA non-approval letter in 2017, despite receiving a favourable review by the FDA’s Oncologic Drugs Advisory Committee (ODAC) and an FDA non-approval letter in 2015 for an earlier formulation.

Oncologists from the US reviewed relevant peer-reviewed articles with use of MEDLINE (PubMed), Embase (Ovid), and Web of Science. Search terms included ‘erythropoietin’, ‘biosimilars’, ‘follow-on biologics’, ‘similar biologic products’, ‘subsequent entry biologics’, ‘follow-on biologic products’ and ‘similar biologic medicinal products’. The search was carried out on articles published between January 2005 and January 2021, in English or Japanese.

From the results of their search the authors discuss the 2018 FDA approval, the 2017 FDA ODAC Committee review and the FDA complete response letters in 2015 and 2017; review concepts of litigation, naming, labelling, substitution, interchangeability and pharmacovigilance; review European and US oncology experiences with biosimilar epoetin and review the safety of erythropoiesis-stimulating agents [2].

In 2020, policy statements from health insurance providers Aetna, UnitedHealthcare and Humana indicated that new patients starting epoetin oncology must use biosimilar epoetin unless medical need for other epoetins is documented.

Empirical studies report that as of 2012, reference epoetin use decreased from 40%–60% of all patients with cancer with chemotherapy-induced anaemia to < 5% of such patients because of safety concerns. Between 2018 and 2020, biosimilar epoetin use varied, increasing to 81% among one private insurer’s patients covered by Medicare# whose cancer care is administered with Oncology Analytics and to 41% with the same private insurer’s patients with cancer covered by commercial health insurance and administered by the private insurer, to 0% in several Veterans Administration Hospitals, increasing to 100% in one large county hospital in California and with yet-to-be-reported data from most oncology settings.

The authors conclude that biosimilar epoetin appears to have overcome some barriers since 2015, although current uptake in the US is variable. Pricing and safety considerations for all erythropoiesis-stimulating agents are primary determinants of biosimilar epoetin oncology uptake.

Implications for practice

Few oncologists understand substitution and interchangeability of biosimilars with reference drugs. Epoetin biosimilar is new to the market and physician and patient understanding is limited. The development of epoetin biosimilar is not familiar to oncologists [2].

Article [2] abstracted by Article abstracted by Charles L Bennett, Toni Stephenson Lymphoma Center, the Hematologic Malignancies Research Institute, the Beckman Research Institute, of the City of Hope Comprehensive Cancer Center, Duarte, California and the College of Pharmacy, University of South Carolina, Columbia, South Carolina, USA.

^#Medicare is a national social insurance programme, administered by the US federal government since 1966. It provides health insurance for Americans aged 65 and older who have worked and paid into the system, as well as to younger people with disabilities.

Competing interests: The authors of the research paper [2] reported conflicts of interest, including having financial relationships with various pharmaceutical companies. For full details of the authors’ conflict of interest, see the research paper [2].

Provenance and peer review: Commissioned; internally peer reviewed.

References
1. GaBI Online – Generics and Biosimilars Initiative. FDA approves epoetin alfa biosimilar Retacrit [www.gabionline.net]. Mol, Belgium: Pro Pharma Communications International; [cited 2021 Aug 20]. Available from: www.gabionline.net/biosimilars/news/FDA-approves-epoetin-alfa-biosimilar-Retacrit
2. Bennett CL, Nagai S, Bennett AC, Hoque S, Nabhan C, Schoen MW, et al. The first 2 years of biosimilar epoetin for cancer and chemotherapy-induced anemia in the U.S.: a review from the Southern Network on Adverse Reactions. Oncologist.