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

Biosimilars are biologic drug products that are highly similar to reference products in analytic features, pharmacokinetics and pharmacodynamics, immunogenicity, safety, and efficacy. Biosimilar epoetin received Food and Drug Administration (FDA) approval in 2018. The manufacturer received an FDA nonapproval letter in 2017, despite receiving a favorable review by FDA's Oncologic Drugs Advisory Committee (ODAC) and an FDA nonapproval letter in 2015 for an earlier formulation. We 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, labeling, substitution, interchangeability, and pharmacovigilance; review European and U.S. oncology experiences with biosimilar epoetin; and review the safety of erythropoiesis-stimulating agents. In 2020, policy statements from AETNA, United Health Care, and Humana indicated that new epoetin oncology starts must be for 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 anemia 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. We conclude that biosimilar epoetin appears to have overcome some barriers since 2015, although current uptake in the U.S. 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.

Hematopoietic Growth Factors in the Management of Anemia and Febrile Neutropenia

Chemotherapy-induced anemia (CIA) in cancer patients correlates with poor performance status and decreased quality of life. Currently recommended causal therapies are erythropoiesis-stimulating agents (epoetins), iron substitution, or a combination of both. Guidelines recommend considering red blood cell (RBC) transfusions for symptomatic anemia at a hemoglobin (Hb) level of <8 g/dl. Granulocyte colony-stimulating factor (G-CSF) is recommended if the risk of febrile neutropenia (FN) following from the chosen chemotherapy protocol is ≥20%. If a chemotherapy is planned that induces a moderate FN risk (10-20%), the individual overall FN risk should be assessed prior to each chemotherapy cycle, taking into account patient- or tumor-related risk factors. G-CSF is required when risk factors such as age ≥ 65 years, advanced disease or relevant comorbidity, or previous neutropenia complications are present. Neutropenia that required a shift in chemotherapy is also an indication for G-CSF prophylaxis in subsequent cycles, in order to maintain the planned dose intensity. The use of G-CSF improves patient survival and reduces the rate of neutropenia complications.

Biosimilar Erythropoiesis-Stimulating Agents in Chronic Kidney Disease

Anemia is a well-known complication of advanced CKD and treatment with erythropoietin analogues (epoetin) remains a key component of management. Although biologic agents, including epoetin, play an extremely important role in the treatment of various medical conditions, their cost can be prohibitive. As a result, several biosimilar agents have now been approved by the U.S. Food and Drug Administration. Biosimilar epoetin has been used in Europe since 2007. In this article, we will review biosimilar development and focus on the first approved biosimilar epoetin in the United States, epoetin alfa-epbx.

Early response to erythropoiesis-stimulating agents in non-dialysis chronic kidney disease patients

BACKGROUND

Renal anemia complicated with chronic kidney disease is usually treated with erythropoiesis-stimulating agents (ESAs). However, few studies have compared the early response of hemoglobin (Hb) to different kinds of ESAs.

METHODS

The effects of three types of ESAs-epoetin alfa or beta (EPO), darbepoetin alfa (DPO), and epoetin beta pegol (EPObp)-on renal anemia were followed in 416 pre-dialysis chronic kidney disease (CKD) patients. After the initial 12-week administration of ESAs, ΔHb/ESA dose/kg was calculated as an index of efficacy of each ESA. Furthermore, independent variables associated with ΔHb/ESA dose/kg (dependent variable) were determined using multiple linear regression analysis. The ten independent variables selected for analysis were: presence of diabetic nephropathy, estimated glomerular filtration rate (eGFR), Hb, albumin, iron (Fe), transferrin saturation (TSAT), ferritin, phosphate (P), intact parathyroid hormone (iPTH), and C-reactive protein.

RESULTS

The efficacy of DPO and EPObp were similar and higher than EPO. TSAT was most strongly correlated with ΔHb/EPO dose/kg in all three types of ESAs. Other significant independent factors were Hb, albumin, P, iPTH, and diabetic nephropathy in the EPO group, eGFR in the DPO group, and Fe in the EPObp group. The adjusted coefficient of determination (R (2)) ranged from 0.415 to 0.520 in the three ESA groups.

CONCLUSIONS

The study results suggest that TSAT is the best predictor of the initial 12-week responsiveness to ESA, irrespective of the type. Variables not investigated in this study also affect responsiveness to ESA in Japanese pre-dialysis CKD patients.

Biosimilar ESAs: a comparative review

BACKGROUND

The management of anaemia in patients with chronic kidney disease has been transformed by development of erythropoiesis-stimulating agents (ESAs). Following expiry of the patent of the originator epoetin alfa in Europe, a number of biosimilar ESAs have been licensed for use in the nephrology setting. Biosimilars are biological medicines that are approved via stringently defined regulatory pathways on the basis that they have demonstrated comparable safety, efficacy and quality to their reference product.

OBJECTIVES

As nurses have a pivotal role in patient care, not only administering medications but also educating patients about their treatment options, it is important that nurses understand the differences between biosimilar medicines and their reference products and appreciate the stringent regulatory requirements for approval of biosimilars.

METHODS

In this review, we use epoetin zeta as a case study to highlight practical considerations of using biosimilar ESAs in the management of patients with kidney disease.

RESULTS AND CONCLUSION

Biosimilar products, such as epoetin zeta, may offer a range of features to patients, nurses and physicians, such as greater flexibility over dose and route of administration, in addition to greater access to biological medicines through cost savings.

APPLICATION TO PRACTICE

Renal nurses play a significant role in the management of patients with kidney disease and anaemia, not only having an important role in the delivery of medicine but also in the education of patients. This review discusses some of the practical aspects associated with the use of biosimilar medicines to assist nurses in making informed decisions over their use.

Similar Outcomes for Two Anemia Treatment Strategies among Elderly Hemodialysis Patients with Diabetes

BACKGROUND/AIMS

To compare mortality and cardiovascular risk in elderly dialysis patients with diabetes under two clinical strategies of anemia correction: maintaining hematocrit (Hct) between 34.5 and < 39.0% (high Hct strategy), and between 30.0 and <34.5% (low Hct strategy) using intravenous alpha epoetin.

METHODS

Observational data were used to emulate a randomized trial in which diabetic patients who initiated hemodialysis in 2006-2008 were assigned to each anemia correction strategy. Inverse-probability weighting was used to adjust for measured time-dependent confounding.

RESULTS

Comparing high with low hematocrit strategy, the hazard ratio (95% confidence interval) was 1.07 (0.83, 1.38) for all-cause mortality and 1.00 (0.81, 1.24) for a composite mortality and cardiovascular endpoint.

CONCLUSIONS

Among a cohort of elderly hemodialysis patients with diabetes, no differences were found between the low and high hematocrit strategies. A lower target hematocrit - per current Food and Drug Administration (FDA) guidelines - appears to be as safe as higher targets among this population.