Evaluation of the safety and immunogenicity of subcutaneous HX575 epoetin alfa in the treatment of anemia associated with chronic kidney disease in predialysis and dialysis patients

An Institutional Guide for Formulary Decisions of Biosimilars

Biologics have changed the landscape for the management of many debilitating chronic diseases but account for a significant expenditure of medications globally. Fortunately, advances in technology paved the way for the introduction of biosimilars, which are highly similar to the originator biologics. In the quest to reduce the budget impact of biologics, organizations have begun to adopt biosimilars. Institutions evaluating biosimilars for inclusion in the hospital formulary must make informed formulary decisions by conducting a thorough review of key elements for evaluation of biosimilars and address the multidimensional aspects during the selection process of different biosimilar products. Therefore, we aim to present an institutional guide of these elements to inform formulary decisions. These key elements include biosimilar evaluation for formulary addition; regulatory approval; substitution, interchangeability, and switching; extrapolation; product characteristics, manufacturing, and supply chain issues; pharmacoeconomic evaluations; traceability, nomenclature, and coding; education; and pharmacovigilance.

Epoetin alfa biosimilar (HX575): A review of 15 years' post-approval clinical experience

Biosimilars offer the potential to expand patient access and reduce healthcare costs. Therefore, it is of importance that clinicians and patients are reassured about their efficacy and safety in practice. In 2007, Binocrit® (HX575; Sandoz GmbH, Kundl, Austria) was the first epoetin alfa biosimilar approved for use in chemotherapy induced anaemia (CIA), chronic renal failure (CRF), and more recently myelodysplastic (MDS) anaemia. Since its approval, there has been a plethora of data demonstrating the well-tolerated safety profile of HX575. This review will outline the safety results collected from key studies that have added to the extensive HX575 (Binocrit® unless otherwise stated) clinical experience. With a focus on all approved indications, we will review the safety data collected across a range of study types, to further consolidate the reassurance for the use of HX575 in these indications.

[Anti-cytokine autoantibodies: Review of the literature]

Anti-cytokine antibodies (ACA) are an emerging cause of acquired immunodeficiency, especially in previously healthy adults. The most frequently reported are anti-IFN-γ responsible for disseminated non-tuberculous mycobacteria infections, and anti-GM-CSF mainly in mycobacteria, cryptococcosis and nocardiosis infections. The presence of anti-IFN-α in severe COVID-19 infections has recently been described. The search for and detection of these ACAs in an unusual infection situation makes it possible to set up specific therapies in addition to the anti-infective treatment. ACAs are also frequent in various autoimmune pathologies where, in addition to being indicators of the breakdown of immune tolerance, they can modulate the activity of the disease according to their cytokine target. In this review of the literature, we will focus on the epidemiology and the clinical impact of these ACAs in healthy subjects and in infectious or dysimmune diseases.

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

Introduction: 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. Areas covered: 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. Expert opinion: 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.

TCPro: an In Silico Risk Assessment Tool for Biotherapeutic Protein Immunogenicity

Most immune responses to biotherapeutic proteins involve the development of anti-drug antibodies (ADAs). New drugs must undergo immunogenicity assessments to identify potential risks at early stages in the drug development process. This immune response is T cell-dependent. Ex vivo assays that monitor T cell proliferation often are used to assess immunogenicity risk. Such assays can be expensive and time-consuming to carry out. Furthermore, T cell proliferation requires presentation of the immunogenic epitope by major histocompatibility complex class II (MHCII) proteins on antigen-presenting cells. The MHC proteins are the most diverse in the human genome. Thus, obtaining cells from subjects that reflect the distribution of the different MHCII proteins in the human population can be challenging. The allelic frequencies of MHCII proteins differ among subpopulations, and understanding the potential immunogenicity risks would thus require generation of datasets for specific subpopulations involving complex subject recruitment. We developed TCPro, a computational tool that predicts the temporal dynamics of T cell counts in common ex vivo assays for drug immunogenicity. Using TCPro, we can test virtual pools of subjects based on MHCII frequencies and estimate immunogenicity risks for different populations. It also provides rapid and inexpensive initial screens for new biotherapeutics and can be used to determine the potential immunogenicity risk of new sequences introduced while bioengineering proteins. We validated TCPro using an experimental immunogenicity dataset, making predictions on the population-based immunogenicity risk of 15 protein-based biotherapeutics. Immunogenicity rankings generated using TCPro are consistent with the reported clinical experience with these therapeutics.

Investigating Serious Adverse Drug Reactions in Patients Receiving Erythropoiesis-Stimulating Agents: A Root Cause Analysis Using the "ANTICIPATE" Framework

BACKGROUND

Unexpected serious adverse drug reactions (sADRs) affecting patients with chronic kidney disease (CKD) who received erythropoiesis-stimulating agents were identified by study co-authors. These included pure red cell aplasia (PRCA) after administration of the Eprex formulation of epoetin or the epoetin biosimilar HX575 and fatal anaphylaxis associated with peginesatide, an erythropoietin receptor agonist. We developed and applied a structured framework to describe these sADRs, including root cause analyses and eradication efforts.

METHODS

A 10-step framework termed "ANTICIPATE," focusing on signal identification, incidence, causality, and eradication guided our evaluations.

RESULTS

Initial cases were identified by a hematologist (Eprex), clinical study monitors (HX575), and 4 nurses (peginesatide). The number of persons with individual ADRs was 13 PRCA cases for epoetin, 2 antibody-mediated PRCA cases for HX575, and 5 fatal anaphylaxis cases for peginesatide. Initial incidence estimates per 1000 treated persons were 0.27 for Eprex-associated PRCA, 11 for HX575-associated PRCA, and 0.38 for peginesatide fatalities. Likely causes were subcutaneous administration of epoetin formulated with polysorbate 80 (Eprex), tungsten leaching from pins included in product syringes (HX575), and inclusion of a phenol stabilizer (peginesatide). Eradication strategies included restricting Eprex administration to the intravenous route, excluding tungsten from HX575 syringes, and for peginesatide, proposed eradication was to return to single-dose vials without preservatives.

CONCLUSION

Although the number of cases of each sADR was small, eradication was successful for 2 sADRs, and a proposed eradication was developed for a third sADR. The structured framework used to describe the above 3 sADRs in patients with CKD can also be used in other clinical settings.

Epoetin Biosimilars in the Treatment of Chemotherapy-Induced Anemia: 10 Years' Experience Gained

High-quality, safe, and effective biosimilars have the potential to increase access to biological therapies worldwide and to reduce cancer care costs. The European Medicines Agency (EMA) was the first regulatory authority to establish legislative procedures for the approval of biosimilars when they published their guidelines on similar biological medicinal products in 2005. Biosimilar epoetins were first approved in 2007, and a wealth of data has been collected over the last decade. Two biosimilar epoetins (under five commercial names) have been approved by the EMA so far. The availability of epoetin biosimilars generated discussion among the oncology community regarding prescribing these products, their efficacy, and their safety. These agents are approved only if they are shown in extensive analytical and clinical testing to have comparable quality, safety, and efficacy to the reference medicine, and real-world studies provide further data that biosimilar epoetins are an effective and well-tolerated option for the treatment of chemotherapy-induced anemia in patients with cancer. Other countries have adopted similar regulatory pathways to those in Europe and have approved epoetin biosimilars. The now extensive European experience with biosimilar epoetins should reassure regulators from other territories.

Epoetin Biosimilars in the Treatment of Renal Anemia: What Have We Learned from a Decade of European Experience?

Biosimilars are biological medicines that are approved via stringently defined regulatory pathways on the basis that comparable safety, efficacy, and quality have been demonstrated to their reference medicine. The advantage of biosimilar drugs is that they may be less expensive than the reference medicine, allowing for greater patient access and cost savings in already stretched healthcare budgets. Biosimilar epoetins have been available in Europe for a decade. Complementing in vitro and preclinical characterization, and pharmacokinetic/pharmacodynamic studies, clinical trials provided the additional data needed to reassure European authorities that biosimilar epoetins were sufficiently similar to the reference epoetin to warrant approval. Post-approval, real-world studies have provided further evidence that biosimilar epoetins are an effective and well-tolerated option for the treatment of renal anemia, with ongoing pharmacovigilance and observational studies monitoring for any unexpected long-term signals that have not been identified in clinical development studies. As the evidence and experience with these products increase, many of the initial concerns are being alleviated. Nephrologists can be increasingly confident that European Medicines Agency-approved biosimilars offer high-quality, affordable, effective alternatives to existing reference medicines used to treat renal anemia, and may help yield cost savings and improve patient access.

A Comparison of the Safety and Efficacy of HX575 (Epoetin Alfa Proposed Biosimilar) with Epoetin Alfa in Patients with End-Stage Renal Disease

BACKGROUND

HX575 (biosimilar epoetin alfa) was approved in Europe in 2007 for the treatment of chronic kidney disease (CKD)-related anemia. This study assessed the clinical equivalence of HX575 with the US-licensed reference epoetin alfa (Epogen®/Procrit®, Amgen/Janssen) following subcutaneous (SC) administration in dialysis patients with CKD-related anemia.

METHODS

This randomized, double-blind, parallel-group, multicenter study (NCT01693029) was conducted at 49 US clinical sites. Eligible patients were aged ≥18 years, had end-stage renal disease, were on hemodialysis or peritoneal dialysis for ≥6 months (or ≥12 months in the case of a failed kidney transplant), and were receiving treatment with stable SC doses of epoetin alfa. Eligible patients also had mean hemoglobin (Hb) concentration between 9.0 and 11.5 g/dL during the screening period. The primary endpoint was the mean absolute change in Hb concentration between the screening/baseline period (week-4 to week-1) and the evaluation period (weeks 21 to 28).

RESULTS

Hb values at the end of the evaluation period and the Hb change from baseline to evaluation period were similar between treatment groups. The estimated difference between groups in mean absolute change in Hb concentration was -0.093 g/dL, with 90% CI (-0.23 to 0.04) entirely within the pre-specified equivalence limits (-0.5 to 0.5 g/dL). The safety profile of each medicine was similar and as expected in dialysis patients, and neither method of treatment led to the development of neutralizing, clinically relevant antibodies.

CONCLUSIONS

SC HX575 in dialysis patients with renal anemia was therapeutically equivalent to the reference medicine in terms of maintaining stable Hb levels and safety.