Key concepts and critical issues on epoetin and filgrastim biosimilars. A position paper from the Italian Society of Hematology, Italian Society of Experimental Hematology, and Italian Group for Bone Marrow Transplantation

Use of Biosimilars: A Systematic Review of Published Position Statements and Recommendations from Health Organisations and Societies

BACKGROUND

Hesitation about using biosimilars still exists among healthcare professionals (HCPs), despite extensive experience with their use. Globally, several health organisations and societies from various specialties have issued biosimilar position statements to guide the use of biosimilars in their specialties. However, it is uncertain how similar or different their positions or recommendations are or whether these positions have evolved with the increased experience and availability of new evidence.

OBJECTIVES

The study aimed to describe and assess the recommendations of published position statements regarding several aspects of biosimilars across specialties and determine whether these positions have changed with the emergence of new evidence.

METHODS

We systematically searched for published position statements of biosimilars in online databases and included statements written in English. The search was from the inception of the databases until May 2023. Two reviewers independently extracted the data. Only position statements that included recommendations to guide the use of biosimilars in clinical practice and were issued by health organisations and societies, including expert panels, were included. We synthesised recommendations on five aspects: prescribing practice, extrapolation of indication, interchangeability, treatment initiation with biosimilars in biologic-naïve patients, and pharmacovigilance.

RESULTS

The review included 25 papers involving eight specialties, 16 of which were from European countries, 1 from an international organisation representing 49 countries, and 6 from various countries. The papers were published between 2009 and 2020, with 19 published between 2015 and 2020. Of the five aspects of biosimilars assessed, nearly half (11 of 25) of the papers at the time they were published did not base their positions on a scientific or evidence-based approach. Only 4 of the 25 position papers were identified as revisions of their previous papers. With increasing experience in biosimilars and the emergence of new evidence, about 60% (16 of 25) of the papers contained outdated recommendations, particularly on two aspects. They were extrapolations of indications and interchangeability (including switching). The recommendations for most papers for three other aspects were still appropriate. These were prescribing biosimilars by their brand name and active ingredient, initiating treatment with biosimilars in biologic-naïve patients, and monitoring the long-term safety of biosimilars through pharmacovigilance. For four of the revised papers, their position evolved from opposing indication extrapolation for biosimilars to accepting it, while the position of two papers shifted from not recommending biosimilar switching to permitting the practice. Meanwhile, most papers were against automatic substitution by pharmacists because the evidence for this practice was still limited.

CONCLUSIONS

Across specialties, the variability among the position statements is seen for extrapolation of indications for biosimilars and interchangeability (including switching). This requires a revision, considering the latest evidence and growing experience with the use of biosimilars in extrapolated indications and with switching.

Oncology biosimilars: New developments and future directions

Biologicals have become an integral part of cancer treatment both as therapeutic agents and as supportive care agents. It is important to know that biologics are large, complex molecular entities requiring extensive immunogenicity testing and pharmacovigilance strategies to ensure no immune response is evoked in the body. Oncology's pharmacological market is dominated by biologics; however, their high development and manufacturing costs are burdensome to health care systems. Biologics being the most expensive prescription drugs on the market limit the accessibility for necessary treatment in the case of many patients. As biologics patents expire, the development of biosimilars is underway in an effort to lower costs and enable patients to access new cancer therapies. Regulatory guidelines for biosimilars have now been established and are constantly being revised to address any issues, facilitating their robust development. Moreover, many scientific societies offer guidance to help stakeholders better understand current regulations and biosimilar's safety. Despite the potential cost benefits, lack of knowledge about biosimilars, and the possibility of immunogenicity have created an uncertain environment for healthcare professionals and patients. In this review, we provide an overview of relevant legislation and regulations, pharmacoeconomics, and stakeholder perceptions regarding biosimilars. The article also describes biosimilars in development, as well as the ones currently available on the market.

Response Assessment to Erythropoietin-Zeta (Epo-Alpha Biosimilar) Therapy in Low-Risk Myelodysplastic Syndromes

Background. This prospective observational study aimed to verify the efficacy of erythropoietin zeta in the treatment of patients with low-risk myelodysplastic syndrome. Methods. Patients with low/int-1 IPSS risk and serum erythropoietin level below 500 U/L were enrolled. Treatment consisted of erythropoietin zeta 40,000 U subcutaneously once a week. The primary endpoint was the erythroid response. According to Simon’s two-stage statistical design, 36 patients were recruited. The median age was 75 years (range 56–83 years), male/female ratio was 1.1/1, median baseline serum erythropoietin was 57.9 U/L (range 9.4–475 U/L). 53% of patients had low-risk disease, while the remaining had Int-1 risk. Results. After 8 weeks, a significant response (rise in Hb levels of at least 1.5 g/dL) was achieved in 18 patients (50%) out of 36. However, 17 patients did not improve; 8/17 patients pursued the 40,000 U weekly schedule of erythropoietin zeta, and 4/8 (50%) of them reached the erythroid response after 16 weeks. Nine patients underwent dosage doubling (40,000 U twice per week), and 5/9 (55%) of them achieved the erythroid response. Conclusion. Compared with data from the literature, this prospective study revealed that EPO-zeta is a safe and effective therapeutic option in low-risk MDS patients.

ATR-FTIR spectroscopy and spectroscopic imaging for the analysis of biopharmaceuticals

Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopy is a label-free, non-destructive technique that can be applied to a vast range of biological applications, from imaging cancer tissues and live cells, to determining protein content and protein secondary structure composition. This review summarises the recent advances in applications of ATR-FTIR spectroscopy to biopharmaceuticals, the application of this technique to biosimilars, and the current uses of FTIR spectroscopy in biopharmaceutical production. We discuss the use of ATR-FTIR spectroscopic imaging to investigate biopharmaceuticals, and finally, give an outlook on the possible future developments and applications of ATR-FTIR spectroscopy and spectroscopic imaging to this field. Throughout the review comparisons will be made between FTIR spectroscopy and alternative analytical techniques, and areas will be identified where FTIR spectroscopy could perhaps offer a better alternative in future studies. This review focuses on the most recent advances in the field of using ATR-FTIR spectroscopy and spectroscopic imaging to characterise and evaluate biopharmaceuticals, both in industrial and academic research based environments.

Emerging Role of Biosimilars in Oncology-Hematology in Saudi Arabia: A Practical Perspective

Biologics are significant drivers of globally escalating healthcare costs. Biosimilars have potential to offer cost savings with comparable efficacy and safety to innovator products and increase the access of treatment to more patients. This study aimed to increase understanding and perception of biosimilars concept. It also described the pharmacoeconomic impact of biosimilar in oncology and formulary consideration of oncology biosimilars substituting with their originators in major oncology centers in the Saudi Arabia. A biosimilar is a biological product that is similar to a reference biopharmaceutical product. As the manufacturing process hinders the ability to identically replicate the structure of the original product, biosimilar cannot be described as an absolute equivalent of the original medication. Different regulatory agencies such as United States Food and Drug Administration, European Medicines Agency, and Saudi Food and Drug Authority have approved several biosimilars of oncology biologics. The experience of biosimilar use in Europe and USA provides valuable insights into the use of biosimilars. The widespread use of biosimilars has the potential to reduce healthcare expenditure, as well as improving access without compromising patient outcomes. There is a need for increasing awareness about biosimilars to improve acceptance rates. The use of biosimilar filgrastim in Ministry of National Guard Health Affairs, Saudi Arabia, has resulted in a significant cost saving annually. It was proposed that further substitution and switching to biosimilars in oncology would lead to major savings in resources.

Quality Comparison of Biosimilar and Copy Filgrastim Products with the Innovator Product

Purpose

Filgrastim, a recombinant human granulocyte-colony stimulating factor, is widely used to treat congenital and acquired neutropenia. Following patent expiration of the innovator filgrastim product, biosimilar filgrastim products have been approved in the EU and shown to be comparable with the innovator with respect to quality, safety and efficacy. In less regulated markets, copy filgrastim products are available but data about their quality are scarce. In the present study, we provide a head-to-head comparative study on the quality of biosimilar and copy filgrastim products.

Methods

Innovator filgrastim product, Neupogen®, two EU-licensed biosimilars, Zarzio® and Tevagrastim®, and two copy filgrastim products, Biocilin® and PDgrastim®, were subjected to peptide mapping, circular dichroism spectroscopy, fluorescence spectroscopy, sodium dodecyl sulfate polyacrylamide gel electrophoresis, high performance size-exclusion chromatography, reversed-phase ultra-performance liquid chromatography, endotoxin test, flow imaging microscopy and in vitro potency assay.

Results

Zarzio® and Tevagrastim® have comparable quality to Neupogen®, while Biocilin® showed a significantly lower and PDgrastim® a higher specific activity. Moreover, PDgrastim® showed a higher level of impurities and a lower thermo stability than the other products.

Conclusions

Except for the deviating specific activities of the two copy filgrastim products, we found no substantial differences in product quality between the filgrastim products studied.

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.

Medical and ethical considerations on hematopoietic stem cells mobilization for healthy donors

Hematopoietic stem cell transplantation is a common procedure potentially beneficial to many individuals with cancer, hematological, or inherited disorders, and has highlighted the need of related or unrelated donors to perform allograft. Donation of hematopoietic stem cells, either through bone marrow harvest or peripheral blood stem cell collection, is well-established and widespread. Over the past two decades, the peripheral blood stem cell collection by aphaeresis has become the main source of hematopoietic stem cells for transplantation, due to faster engraftment and practicability and lower risk of relapse for high-risk patients. For peripheral blood stem cell donation, donors require mobilization of hematopoietic stem cells from bone marrow into the blood stream. This is performed by growth factors injections. This article is a review of reported applications of growth factors (original granulocyte colony stimulating factor and its biosimilars), for healthy donors' peripheral blood stem cell mobilization, in terms of toxicity, side effects, efficacy and follow-up. There is still an ethical dilemma for clinicians involved in allograft, because they expose healthy donors to drugs. It is important to dispel some of the critical concerns regarding their use in healthy volunteers, particularly because they receive no personal therapeutic benefit from this procedure.

Patient Access, Unmet Medical Need, Expected Benefits, and Concerns Related to the Utilisation of Biosimilars in Eastern European Countries: A Survey of Experts

This policy research aims to map patient access barriers to biologic treatments, to explore how increased uptake of biosimilars may lower these hurdles and to identify factors limiting the increased utilisation of biosimilars. A policy survey was developed to review these questions in 10 Central and Eastern European (CEE) and Commonwealth of Independent States (CIS) countries. Two experts (one public and one private sector representative) from each country completed the survey. Questions were related to patient access, purchasing, clinical practice, and real-world data collection on both original biologics and biosimilars. Restrictions on the number of patients that can be treated and related waiting lists were reported as key patient access barriers. According to respondents, for both clinicians and payers the primary benefit of switching patients to biosimilars would be to treat more patients. However, concerns with therapeutic equivalence and fear of immunogenicity may reduce utilisation of biosimilars. Similar limitations in patient access to both original biologics and biosimilars raise concerns about the appropriateness and success of current biosimilar policies in CEE and CIS countries. The conceptual framework for additional real-world data collection exists in all countries which may provide a basis for future risk-management activities including vigorous pharmacovigilance data collection.

The Impact of Biosimilars in Supportive Care in Cancer

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Is there a reason for concern or is it just hype? - A systematic literature review of the clinical consequences of switching from originator biologics to biosimilars

INTRODUCTION

While prescribing biosimilars to patients naive to a biologic treatment is a well-accepted practice, switching clinically stable patients from an originator to a biosimilar is an issue for clinicians. Well-designed clinical trials and real-world data which study the consequences of switching from an originator biologic treatment to its biosimilar alternative are limited, especially for monoclonal antibodies. Areas covered: A systematic literature review was conducted on PubMed to identify evidence of the consequences of switching from original biologics to biosimilars. References of included papers were also scrutinized. After a title-, abstract- and full text screening, out of the 153 original hits and 77 additional ones from screening the references, 58 papers (12 empirical papers, 5 systematic reviews and 41 non-empirical papers) were included. Expert opinion: Preventing patients on biologic medicines from switching to biosimilars due to anticipated risks seems to be disproportional compared to the expected cost savings and/or improved patient access. Indeed, it is the opinion of the authors that the concern of switching to biosimilars is overhyped.

Ten years of biosimilars in Europe: development and evolution of the regulatory pathways

A biosimilar is defined by the European Medicines Agency as a biological medicine that is similar to another biological medicine that has already been authorized for use. A science-based regulatory framework to ensure high-quality biosimilars has been established in Europe since 2005 and is monitored and updated on an ongoing basis. The guiding principle of a biosimilar development program is to establish similarity between the biosimilar and the reference medicine by the best possible means, ensuring that the previously proven safety and efficacy of the reference medicinal product also applies to the biosimilar. Development of a biosimilar is underpinned by state-of-the-art analytical techniques to characterize both reference medicines and biosimilars. The extent and nature of the nonclinical in vivo studies and clinical studies to be performed depend on the level of evidence obtained in the previous step(s), including the robustness of the physicochemical, biological, and nonclinical in vitro data. Extrapolation is an important element of the biosimilarity concept. When biosimilar comparability has been demonstrated in one indication, extrapolation of the data package to other indications of the reference medicine could be acceptable, but needs to be scientifically justified and considered in light of the demonstrated level of sameness by all analytical, nonclinical, and clinical data. The credibility of the scientific basis behind the biosimilar concept, and quality of regulatory decision-making, is demonstrated by the successful approval and clinical use of 20 biosimilar medicines since 2006 when Omnitrope^® was the first biosimilar to be approved. The regulatory environment for biosimilars continues to evolve, both in recognition of advances in technology/analytical methods and the availability of new targets for biosimilar development.

Impact of Guidance on the Prescription Patterns of G-CSFs for the Prevention of Febrile Neutropenia Following Anticancer Chemotherapy: A Population-Based Utilization Study in the Lazio Region

Background

Current guidelines recommend prophylaxis with granulocyte colony-stimulating factors (G-CSFs) for patients with cancer who are at greater risk of febrile neutropenia (FN) while receiving chemotherapy. G-CSF biosimilars are available and represent a savings opportunity; however, their uptake has thus far been low.

Objective

Our objective was to evaluate prescribing patterns for G-CSFs in the prevention of chemotherapy-related FN and to evaluate the impact of regional guidance on G-CSF prescription.

Methods

We conducted an observational drug-utilization study in the Lazio region of Italy using the Electronic Therapeutic Plan Registry, which collects information on G-CSF prescriptions reimbursed by the regional health service. This registry includes information on demographics, tumour, indication for G-CSF use and previous G-CSF exposure. All therapeutic plans (TPs) registered from 1 July 2015 to 30 June 2016 were selected. A pharmaceutical policy intervention was implemented in November 2015. We evaluated temporal trends regarding G-CSF substances and compared the frequency of TPs for each G-CSF substance during the pre- and post-intervention periods.

Results

A total of 7082 TPs were eligible for the analysis, corresponding to 6592 patients. The frequency of TPs prescribed after the intervention indicated a significant increase in the use of a filgrastim biosimilar (% difference: 14.4; p < 0.001) and significant decreases in the use of lenograstim (% difference: –6.0; p < 0.001) and pegfilgrastim (% difference: –7.8; p < 0.001). The temporal trends analysis showed an increase in TPs using a filgrastim biosimilar (from 34.4% in July 2015 to 49.8% in June 2016; p < 0.0001) and a decrease in TPs using lenograstim and pegfilgrastim.

Conclusions

This study shows it is possible to change attitudes towards the prescription of less expensive G-CSFs in the FN setting when the prescriber’s decision-making processes are supported by evidence that includes both regulatory and clinical information and the analysis of clinical practice data.

Electronic supplementary material

The online version of this article (doi:10.1007/s40259-017-0214-9) contains supplementary material, which is available to authorized users.

Efficacy and safety of biosimilar epoetin alpha in patients with chronic lymphoid neoplasms and chemotherapy-induced anaemia: An observational, retrospective, monocentric analysis

Epoetin biosimilars are an alternative to originator erythropoietic agents in the treatment of chemotherapy-induced anaemia; however, their effects in patients with lymphoproliferative disorders remain unclear. This analysis examined the response of patients with lymphoproliferative disorders experiencing chemotherapy-induced anaemia to 4- or 8-week treatment with the biosimilar epoetin alpha. Treatment was initiated at first occurrence of haemoglobin (Hb) < 10 g/dL during chemotherapy and was stopped when Hb was >11 g/dL, when chemotherapy was completed, or in case of transfusion dependency. Response to epoetin alpha was defined as an increase in Hb of >1 g/dL or as an Hb > 11 g/dL. Stability was defined as change in Hb of ±1 g/dL, and no response was indicated by a decrease in Hb of >1 g/dL or acquired transfusion dependence. Overall, 65 patients were enrolled (median age 69 years; 47.7% ≥ 70 years old). Mean Hb levels at the initiation of epoetin alpha was 9.3 ± 0.5 g/dL. Mean Hb levels reached 10.7 ± 1.4 and 10.6 ± 1.5 g/dL at weeks 4 and 8, respectively, in patients on first-line chemotherapy and 11.4 ± 1.6 and 9.7 ± 1.3 g/dL in those on a second- or higher-line regimen. Overall, 70.8% of patients responded, 26.1% had stable Hb, and 3.1% did not respond. Delays or interruption of any chemotherapy cycle due to anaemia occurred in 18 patients. The biosimilar epoetin alpha was well tolerated and allowed patients with non-Hodgkin lymphoma or chronic lymphoproliferative disorders to continue their course of chemotherapy by effectively increasing and maintaining adequate concentrations of Hb.

Comparative effectiveness and safety of erythropoiesis-stimulating agents (biosimilars vs originators) in clinical practice: a population-based cohort study in Italy

OBJECTIVES

To evaluate the benefit/risk profile of epoetin α biosimilar with the erythropoiesis-stimulating agents (ESAs) originators when administered to naïve patients from clinical practice.

DESIGN

Population-based observational cohort study.

SETTING

All residents in the Lazio Region, Italy, with chronic kidney disease (CKD) or cancer retrieved from the Electronic Therapeutic Plan (ETP) Register for ESA between 2012 and 2014.

PARTICIPANTS

Overall, 13 470 incident ESA users were available for the analysis, 8161 in the CKD and 5309 in the oncology setting, respectively.

INTERVENTIONS

ESAs identified through the ATC B03XA were divided into 3 groups: (1) biosimilars; (2) epoetin α originator and (3) other originators. Patients were exposed to ESAs from the date of activation of the ETP, until the end of a 6-month follow-up period.

OUTCOME MEASURES

Effectiveness (all-cause mortality and blood transfusion) and safety (major cardiovascular events, blood dyscrasia). A composite outcome including all-cause mortality, blood transfusion and major cardiovascular events was predefined. HRs of any outcome were estimated through Cox regression.

RESULTS

We found no differences between patients on biosimilars or all originators with regard to the risk estimates of all-cause mortality, blood transfusion, major cardiovascular events and blood dyscrasia in the CKD setting. The composite outcome confirmed these results (biosimilars vs epoetin α originators: adjusted HR=1.02, 95% CI 0.78 to 1.33; biosimilars vs other originators: adjusted HR=1.09, 95% CI 0.85 to 1.41). Comparable risk estimates were observed between biosimilars and all originators in the oncology setting.

CONCLUSIONS

In both settings, our findings are suggestive of no difference between biosimilars and originators on relevant effectiveness and safety outcomes. This study may contribute to settling future drug policy for the health services and provides reassurance on the approval pathway for biosimilars. The oncology setting merits further research, taking into account tumour types, tumour stage and anticancer chemotherapy administered.

Assessing the Immunogenicity of Biopharmaceuticals

Biopharmaceuticals have the potential to raise an immunogenic response in treated individuals, which may impact the efficacy and safety profile of these drugs. As a result, it is essential to evaluate immunogenicity throughout the different phases of the clinical development of a biopharmaceutical, including post-marketing surveillance. Although rigorous evaluation of biopharmaceutical immunogenicity is required by regulatory authorities, there is a lack of uniform standards for the type, quantity, and quality of evidence, and for guidance on experimental design for immunogenicity assays or criteria to compare immunogenicity of biopharmaceuticals. Moreover, substantial technological advances in methods to assess immune responses have yielded higher immunogenicity rates with modern assays, and limit comparison of immunogenicity of biopharmaceuticals outside of head-to-head clinical trials. Accordingly, research programs, regulatory agencies, and clinicians need to keep pace with continuously evolving analyses of immunogenicity. Here, we review factors associated with immunogenicity of biopharmaceuticals, potential clinical ramifications, and current regulatory guidance for evaluating immunogenicity, and discuss methods to assess immunogenicity in non-clinical and clinical studies. We also describe special considerations for evaluating the immunogenicity of biosimilar candidates.

Healthy donor hematopoietic stem cell mobilization with biosimilar granulocyte-colony-stimulating factor: safety, efficacy, and graft performance

BACKGROUND

Biosimilar granulocyte-colony-stimulating factors (G-CSFs) have been available in the European Union since 2008, and Sandoz' biosimilar filgrastim was approved in the United States in March 2015 for all of the reference product's indications except acute radiation syndrome. Biosimilar G-CSFs have been largely embraced by the medical community, except for some reservations about healthy-donor stem cell mobilization, for which use outside of clinical studies was cautioned against by some members of the scientific community.

STUDY DESIGN AND METHODS

In a two-center safety surveillance study (National Clinical Trial NCT01766934), 245 healthy volunteer stem cell donors were enrolled. Of 244 donors who began mobilization with twice-daily Sandoz biosimilar filgrastim, 242 received a full (n = 241) or partial (n = 1) course of G-CSF and underwent apheresis. Efficacy and safety were assessed and are reported here.

RESULTS

Biosimilar filgrastim was accompanied by the typical G-CSF class-related adverse effects of expected frequency and severity. Median mobilization for CD34-positive stem cells was 97/µL (range, 20-347/µL); after one apheresis (91%) or two aphereses (9%) from all but three donors (1.2%), cell doses in excess of the typical 4 × 10⁶ CD34-positive cells/kg of the recipient had been collected (range, 3-52 × 10⁶ /kg). Biochemical and hematologic alterations were consistent with previous reports; all had normalized by the first follow-up 1 month after mobilization. Stem cell products engrafted with typical probability and kinetics for G-CSF-mobilized stem cell products.

CONCLUSION

These data support the use of biosimilar filgrastim for healthy-donor stem cell mobilization as safe and effective.

Update on biosimilars of granulocyte colony-stimulating factor - when no news is good news

PURPOSE OF REVIEW

With the approval of the first biosimilar granulocyte colony-stimulating factor (G-CSF), biosimilars - copies of therapeutic biologicals whose patent protection has expired - have finally reached the US healthcare market. Its advent is an occasion for a closer look at recent insights into biosimilar G-CSF and an attempt at prognosticating the future (future role) of biosimilars in general.

RECENT FINDINGS

Recent literature regarding biosimilar G-CSF orbits significantly around patient access and effects on healthcare expenditure. The advent of biosimilar G-CSF has induced unexpectedly large price reductions for short-acting G-CSF. On the clinical side, little excitement is tangible, probably appropriately so, since clinical data indicate nothing short of biological similarity. Although formal clinical trials are few, the plethora of case series and historic comparisons which have come forth offer reassurance about the appropriateness of the regulators' assessment of biosimilar G-CSF as indeed in all respects biologically similar to the originator.

SUMMARY

All evidence points to an overwhelming similarity of originator and biosimilar G-CSF in all indications. Overall clinical acceptance, albeit possibly significantly dictated by economic pressures, is good. Price reductions exceed predictions and may jeopardize the economic viability of biosimilar programs. A concurrent shift towards long-acting G-CSF ('biobetters') is observed in Europe.

Introduction of Biosimilar Therapeutics Into Nephrology Practice in the United States: Report of a Scientific Workshop Sponsored by the National Kidney Foundation

Biosimilars are biologic medicines highly similar to the reference product with no meaningful clinical differences in terms of safety, purity, and potency. All biologic medicines are produced by living cells, resulting in an inherent heterogeneity in their higher order structures and post-translational modifications. In 2010, the US Congress enacted legislation to streamline the approval process for biosimilars of products losing patent protection, with the goal of decreasing costs and improving patient access to therapeutically important but expensive biologic agents. In 2015, the US Food and Drug Administration approved the first biosimilar agent through this pathway. Approval of additional biosimilar agents in the United States, including those used by nephrologists, is anticipated. Given the relative lack of knowledge regarding biosimilars and their approval process and a lack of trust by the nephrology community regarding their safety and efficacy, the National Kidney Foundation conducted a symposium, Introduction of Biosimilar Therapeutics Into Nephrology Practice in the U.S., September 17 to 18, 2015. Issues related to manufacturing, the regulatory approval process, interchangeability, substitution/switching, nomenclature, and clinician and patient awareness and acceptance were examined. This report summarizes the main discussions at the symposium, highlights several controversies, and makes recommendations related to public policy, professional and patient education, and research needs.

Biosimilar infliximab for inflammatory bowel disease: from concepts to clinical practice. Case study illustrated with CT-P13

The introduction of biologic drugs represents the most significant advance in the management of immune-mediated inflammatory diseases for a decade. However, complex proteins are expensive to produce and manufacture. Biosimilar versions of established biologics are becoming available as another version of the reference medicinal product and are expected to provide substantial cost savings. However, because of their complexity, the approval of biosimilars requires strict controls to ensure that all therapeutically relevant characteristics are comparable to the reference medicinal product. This review summarizes the scientific principles and data requirements underpinning regulatory approval of biosimilars and the assumptions that enable extrapolation of data between indications. These important concepts are exemplified by CT-P13 (Remsima(®), Inflectra(®)), the first biosimilar monoclonal antibody approved in Europe.

Biosimilars: Hope and concern

As patents of the first introduced biologic therapeutics in oncology have begun to expire, competing pharmaceutical companies are allowed to produce and market the same protein as the original agent. These products are called biosimilars. Upon patent expiration, biosimilars would hopefully be a cheaper alternative to the original agent and that is the main reason for their existence. Although the financial aspect is similar to generics, the complex nature of these products generates the need for a distinct regulatory environment. Biosimilars are produced by DNA technology in bacteria, plant cells, or animal cells, while generics are produced by chemical synthesis. Details in the process of synthesis, selection of the microorganism, protein extraction, purification and manufacturing, affect the precise nature of the end product. Monoclonal antibodies are large proteins with four polypeptide chains and interact variably with each other and with the environment. It is important for payors to realize that biosimilars are different from generics; therefore, they need to develop different set of rules for approving, registering, and dispensing biosimilars. Regulators ought to respect the physicians’ request for non-interchangeability and facilitate in any possible way of traceability. Such regulations along with a rigorous pharmacovigilance program will satisfy the concerns for true equivalence in activity and long-term safety. This is the only way to accumulate over time reliable safety information for new biosimilars. In conclusion, the wish born by the medical community and the society for a more affordable health system triggers the emergence of biosimilars, which could meet that goal if properly regulated.

Efficacy of biosimilar granulocyte colony-stimulating factor versus originator granulocyte colony-stimulating factor in peripheral blood stem cell mobilization in de novo multiple myeloma patients

BACKGROUND AIMS

Filgrastim and lenograstim are the standard granulocyte colony-stimulating factor (G-CSF) agents for peripheral blood stem cell mobilization (PBSC) in patients who undergo autologous stem cell transplantation.

METHODS

To assess whether biosimilars are effective, we conducted a single-center, prospective study that included 40 consecutive de novo multiple myeloma patients who received cyclophosphamide 4 g/m(2) per day plus biosimilar filgrastim G-CSF to mobilize PBSC. These patients were compared with a group of 37 patients matched for age, diagnosis, previous chemotherapy and mobilization who had been treated with originator G-CSF. The mean number of CD34+ cells/μL in the peripheral blood was 199.6 ± 207.4 in the biosimilar and 192.8 ± 154.7 in the originator group (P = 0.87). The median number of CD34+ cells/kg recipient collected was 11.5 ± 5.8 and 12.3 ± 5.3 in the biosimilar and originator groups, respectively (P = 0.51). The mobilization failure rate was 2.5% and 2.7% in the biosimilar filgrastim and originator filgrastim cohorts (P = NS), respectively.

RESULTS

Twenty-nine patients in the biosimilar group and 28 patients in the originator group underwent autologous transplantation. There were no statistically significant differences between the biosimilar and originator G-CSF cohorts in terms of hematopoietic recovery parameters and transplant-related toxicities.

CONCLUSIONS

The efficacy of biosimilar G-CSF appears to be equivalent to the reference G-CSF.

Epoetin Alpha and Epoetin Zeta: A Comparative Study on Stimulation of Angiogenesis and Wound Repair in an Experimental Model of Burn Injury

Deep second-degree burns are characterized by delayed formation of granulation tissue and impaired angiogenesis. Erythropoietin (EPO) is able to stimulate angiogenesis and mitosis, activating vascularization and cell cycle. The aim of our study was to investigate whether two biosimilar recombinant human erythropoietins, EPO-α and EPO-Z, may promote these processes in an experimental model of burn injury. A total of 84 mice were used and a scald burn was produced on the back after shaving, in 80°C water for 10 seconds. Mice were then randomized to receive EPO-α (400 units/kg/day/sc) or EPO-Z (400 units/kg/day/sc) or their vehicle (100 μL/day/sc 0.9% NaCl solution). After 12 days, both EPO-α and EPO-Z increased VEGF protein expression. EPO-α caused an increased cyclin D1/CDK6 and cyclin E/CDK2 expression compared with vehicle and EPO-Z (p<0.001). Our study showed that EPO-α and EPO-Z accelerated wound closure and angiogenesis; however EPO-α resulted more effectively in achieving complete skin regeneration. Our data suggest that EPO-α and EPO-Z are not biosimilars for the wound healing effects. The higher efficacy of EPO-α might be likely due to its different conformational structure leading to a more efficient cell proliferation and skin remodelling.

Tbo-Filgrastim versus Filgrastim during Mobilization and Neutrophil Engraftment for Autologous Stem Cell Transplantation

There are limited data available supporting the use of the recombinant granulocyte colony-stimulating factor (G-CSF), tbo-filgrastim, rather than traditionally used filgrastim to mobilize peripheral blood stem cells (PBSC) or to accelerate engraftment after autologous stem cell transplantation (ASCT). We sought to compare the efficacy and cost of tbo-filgrastim to filgrastim in these settings. Patients diagnosed with lymphoma or plasma cell disorders undergoing G-CSF mobilization, with or without plerixafor, were included in this retrospective analysis. The primary outcome was total collected CD34(+) cells/kg. Secondary mobilization endpoints included peripheral CD34(+) cells/μL on days 4 and 5 of mobilization, adjunctive use of plerixafor, CD34(+) cells/kg collected on day 5, number of collection days and volumes processed, number of collections reaching 5 million CD34(+) cells/kg, and percent reaching target collection goal in 1 day. Secondary engraftment endpoints included time to neutrophil and platelet engraftment, number of blood product transfusions required before engraftment, events of febrile neutropenia, and length of stay. A total of 185 patients were included in the final analysis. Patients receiving filgrastim (n = 86) collected a median of 5.56 × 10(6) CD34(+) cells/kg, compared with a median of 5.85 × 10(6) CD34(+) cells/kg in the tbo-filgrastim group (n = 99; P = .58). There were no statistically significant differences in all secondary endpoints with the exception of apheresis volumes processed (tbo-filgrastim, 17.0 liters versus filgrastim, 19.7 liters; P < .01) and mean platelet transfusions (tbo-filgrastim, 1.7 units versus filgrastim, 1.4 units; P = .04). In conclusion, tbo-filgrastim demonstrated similar CD34(+) yield compared with filgrastim in mobilization and post-transplantation settings, with no clinically meaningful differences in secondary efficacy and safety endpoints. Furthermore, tbo-filgrastim utilization was associated with cost savings of approximately $1406 per patient utilizing average wholesale price.

Biosimilar granulocyte-colony-stimulating factor for healthy donor stem cell mobilization: need we be afraid?

Biosimilars are approved biologics with comparable quality, safety, and efficacy to a reference product. Unlike generics, which are chemically manufactured copies of small-molecule drugs with relatively simple chemical structures, the biosimilar designation is applied to drugs that are produced by living organisms, implying much more difficult to control manufacturing and purification procedures. To account for these complexities, the European Medicines Agency (EMA), the US Food and Drug Administration, the Australian Therapeutic Goods Administration, and other regulatory authorities have devised and implemented specific, markedly more demanding pathways for the evaluation and approval of biosimilars. To date, several biosimilars have been approved, including versions of somatropin, erythropoietin, and granulocyte-colony-stimulating factor (G-CSF), and several biosimilar monoclonal antibodies are currently in development. The reference G-CSF product (Neupogen, Amgen) has been used for many years for prevention and treatment of neutropenia and also for mobilization of peripheral blood stem cells (PBSCs). However, concerns have been raised about the safety and efficacy of biosimilar G-CSF during PBSC mobilization procedures, especially in healthy donors. This article reviews the available evidence on the use of biosimilar G-CSF in this setting. Aggregate clinical evidence supports the assessment by the EMA of biosimilar and originator G-CSF as highly biologically similar, with respect to desired and undesired effects.

Regulatory and clinical considerations for biosimilar oncology drugs

Biological oncology products are integral to cancer treatment, but their high costs pose challenges to patients, families, providers, and insurers. The introduction of biosimilar agents-molecules that are similar in structure, function, activity, immunogenicity, and safety to the original biological drugs-provide opportunities both to improve health-care access and outcomes, and to reduce costs. Several international regulatory pathways have been developed to expedite entry of biosimilars into global marketplaces. The first wave of oncology biosimilar use was in Europe and India in 2007. Oncology biosimilars are now widely marketed in several countries in Europe, and in Australia, Japan, China, Russia, India, and South Korea. Their use is emerging worldwide, with the notable exception of the USA, where several regulatory and cost barriers to biosimilar approval exist. In this Review, we discuss oncology biosimilars and summarise their regulatory frameworks, clinical experiences, and safety concerns.

Erythropoiesis-stimulating agents in allogeneic and autologous hematopoietic stem cell transplantation

INTRODUCTION

Erythropoiesis-stimulating agents (ESAs) are used in treating cancer- and chemotherapy-induced anemia with the aim of accelerating the recovery of red blood cells (RBCs), reduce the risks associated with RBC transfusions and improve quality of life.

AREAS COVERED

A systematic review has been conducted to examine the current evidence for the efficacy and safety of using ESAs in hematopoietic stem cell transplants (HSCTs).

EXPERT OPINION

Despite the international recommendations for the use of ESAs in treating different malignancies, there is a lack of guidelines for their use in patients undergoing HSCT. An evaluation of published clinical trials shows that there are no available powerful studies concerning the use of ESAs in this setting, with only heterogeneous and small numbers of patients reported so far. Nevertheless, the more robust and intriguing of these data suggest that the ESA's administration at an appropriate time after the infusion of stem cells may be effective both in autologous and allogeneic HSCTs. New guidelines are required, overseen by an expert in the in the field of stem cell transplantation.

Biosimilars: the science of extrapolation

Despite the establishment of a specific approval pathway, the issuance of detailed scientific guidelines for the development of similar biological medicinal products (so-called "biosimilars") and the approval of several biosimilars in the European Union, acceptance of biosimilars in the medical community continues to be low. This is especially true in therapeutic indications for which no specific clinical trials with the biosimilar have been performed and that have been licensed based on extrapolation of efficacy and safety data from other indications. This article addresses the concerns frequently raised in the medical community about the use of biosimilars in such extrapolated indications and explains the underlying scientific and regulatory decision making including some real-life examples from recently licensed biosimilars.

Epoetin zeta in the management of anemia associated with chronic kidney disease, differential pharmacology and clinical utility

Epoetin zeta was granted marketing authorization in October 2007 by the European Medicines Agency as a recombinant human erythropoietin erythropoiesis-stimulating agent to treat symptomatic anemia of renal origin in adult and pediatric patients on hemodialysis and adults on peritoneal dialysis, as well as for symptomatic renal anemia in adult patients with renal insufficiency not yet on dialysis. Currently, epoetin zeta can be administered either subcutaneously or intravenously to correct for hemoglobin concentrations ≤10 g/dL (6.2 mmol/L) or with dose adjustment to maintain hemoglobin levels at desired levels not in excess of 12 g/dL (7.5 mmol/L). This review article focuses on epoetin zeta indications in chronic kidney disease, its use in managing anemia of renal origin, and discusses its pharmacology and clinical utility.

Chronic inflammatory diseases: do immunological patterns drive the choice of biotechnology drugs? A critical review

Chronic inflammatory diseases represent a heterogeneous group of conditions that can affect practically any organ or system. An increasing number of biologic agents have been developed to selectively target the cell populations and signaling pathways involved in chronic inflammation, including cytokines, monoclonal antibodies and engineered receptors. This approach has been remarkably successful in alleviating some of the signs and symptoms of refractory autoimmune diseases. The use of this therapeutic strategy is likely to increase with the introduction of biosimilar agents. The different nature of these biological products makes the comparison of their pharmaceutical and clinical characteristics difficult, including safety and potency and these issues may be particularly relevant in the case of biosimilars. In addition, the heterogeneity of autoimmune diseases and of autoimmune patients, further adds to the complexity of choosing the right drug for each patient and predicting efficacy and safety of the treatment. In this review, we summarize actual knowledge about current biological agents and their use in autoimmune diseases, with a special emphasis for rheumatoid arthritis, inflammatory bowel diseases and psoriasis. The purpose of this analysis is to address the most critical issues raised by the rapid advancements in this field over recent years, and to acknowledge the potentially valuable gains brought about by the increasing availability of these new biologic agents.

Biosimilars in oncology: from development to clinical practice

Biologics play an integral role in the treatment of cancer not only for their therapeutic effects and ability to improve outcomes, but also as supportive care agents. Biologics are more complex to manufacture and take longer to bring to market. Because biologics are considerably more costly than small-molecule drugs, their use has placed an increasing economic demand on healthcare systems worldwide. Biosimilars are designed to be highly similar to existing branded biologics, but because biologics cannot be exactly copied, biosimilars should not be referred to as generic, exact versions of the innovator biologic. Biosimilars have the potential to increase access and provide lower cost options for cancer care as patent protection for some of the most widely used biologics begins to expire. Regulatory requirements for biosimilars are evolving, as are global harmonization and/or standardization strategies that can facilitate their robust clinical development. This review highlights critical factors involved with the integration of biosimilars into oncology treatment paradigms and practices. Clinicians will likely seek out practice guidelines and position statements from established scientific societies to help evaluate key information regarding biosimilars, such as efficacy, safety, comparability, and interchangeability with the reference biologic. Automatic substitution, nomenclature, extrapolation of clinical data from one indication to another, as well as parameters for ongoing pharmacovigilance are evolving considerations. Education of physicians and other healthcare providers, payers, and patients about biosimilars may facilitate informed decision making, promote acceptance of biosimilars into clinical practice, increase accessibility, and expedite associated health and economic benefits.

A clinical comparison of the efficacy and safety of biosimilar G-CSF and originator G-CSF in haematopoietic stem cell mobilization

BACKGROUND

Recombinant granulocyte colony-stimulating factor (G-CSF) is widely used to mobilize haematopoietic stem cells. We compared the efficacy and safety of a biosimilar G-CSF (Zarzio(®), Sandoz Biopharmaceuticals) with the originator G-CSF (Neupogen(®), Amgen) in patients with haematological malignancies.

METHODS

A total of 108 patients were included in this study, 59 of whom were female (49 male), with an overall median age of 51 years (range 19-69). Patients had multiple myeloma (n=46), non-Hodgkin's lymphoma (n=28), Hodgkin's lymphoma (n=26), or other diagnosis (n=8). After administration of mobilizing regimens (primarily high-dose etoposide, high-dose cyclophosphamide, intermediate-dose Ara-C or ESHAP), patients were randomized to a standard daily 10 μg/kg dose of biosimilar G-CSF (n=54) or originator G-CSF (n=54).

RESULTS

Median duration of G-CSF administration was 8 days with both biosimilar G-CSF (range 4-17) and originator G-CSF (range 4-14). Both groups had a median of one apheresis with a median time until first apheresis of 11 days. There were no statistically significant differences between groups in the mean ± SD number of mobilized CD34+ cells/μL in peripheral blood or the number of CD34+ cells/kg body weight. Five patients (9%) in the originator G-CSF group and six patients in the biosimilar G-CSF group (11%) did not mobilize sufficient CD34+ cells. The adverse event profile was similar between groups.

CONCLUSIONS

A biosimilar G-CSF (Zarzio(®)) demonstrated similar efficacy and safety as the reference originator G-CSF (Neupogen(®)) in hematopoietic stem cell mobilization in patients with haematological malignancies.

Biosimilars: what clinicians should know

Biosimilar medicinal products (biosimilars) have become a reality in the European Union and will soon be available in the United States. Despite an established legal pathway for biosimilars in the European Union since 2005 and increasing and detailed regulatory guidance on data requirements for their development and licensing, many clinicians, particularly oncologists, are reluctant to consider biosimilars as a treatment option for their patients. Major concerns voiced about biosimilars relate to their pharmaceutical quality, safety (especially immunogenicity), efficacy (particularly in extrapolated indications), and interchangeability with the originator product. In this article, the members and experts of the Working Party on Similar Biologic Medicinal Products of the European Medicines Agency (EMA) address these issues. A clear understanding of the scientific principles of the biosimilar concept and access to unbiased information on licensed biosimilars are important for physicians to make informed and appropriate treatment choices for their patients. This will become even more important with the advent of biosimilar monoclonal antibodies. The issues also highlight the need for improved communication between physicians, learned societies, and regulators.

Erythropoietin or darbepoetin for patients with cancer

BACKGROUND

Anaemia associated with cancer and cancer therapy is an important clinical factor in the treatment of malignant diseases. Therapeutic alternatives are recombinant human erythropoiesis stimulating agents (ESAs) and red blood cell transfusions.

OBJECTIVES

To assess the effects of ESAs to either prevent or treat anaemia in cancer patients.

SEARCH METHODS

This is an update of a Cochrane review first published in 2004. We searched the Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE and other databases. Searches were done for the periods 01/1985 to 12/2001 for the first review, 1/2002 to 04/2005 for the first update and to November 2011 for the current update. We also contacted experts in the field and pharmaceutical companies.

SELECTION CRITERIA

Randomised controlled trials on managing anaemia in cancer patients receiving or not receiving anti-cancer therapy that compared the use of ESAs (plus transfusion if needed).

DATA COLLECTION AND ANALYSIS

Several review authors assessed trial quality and extracted data. One review author assessed quality assessment and extracted data, a second review author checked for correctness.

MAIN RESULTS

This update of the systematic review includes a total of 91 trials with 20,102 participants. Use of ESAs significantly reduced the relative risk of red blood cell transfusions (risk ratio (RR) 0.65; 95% confidence interval (CI) 0.62 to 0.68, 70 trials, N = 16,093). On average, participants in the ESAs group received one unit of blood less than the control group (mean difference (MD) -0.98; 95% CI -1.17 to -0.78, 19 trials, N = 4,715). Haematological response was observed more often in participants receiving ESAs (RR 3.93; 95% CI 3.10 to 3.71, 31 trials, N = 6,413). There was suggestive evidence that ESAs may improve Quality of Life (QoL). There was strong evidence that ESAs increase mortality during active study period (hazard ratio (HR) 1.17; 95% CI 1.06 to 1.29, 70 trials, N = 15,935) and some evidence that ESAs decrease overall survival (HR 1.05; 95% CI 1.00 to 1.11, 78 trials, N = 19,003). The risk ratio for thromboembolic complications was increased in patients receiving ESAs compared to controls (RR 1.52, 95% CI 1.34 to 1.74; 57 trials, N = 15,498). ESAs may also increase the risk for hypertension (fixed-effect model: RR 1.30; 95% CI 1.08 to 1.56; random-effects model: RR 1.12; 95% CI 0.94 to 1.33, 31 trials, N = 7,228) and thrombocytopenia/haemorrhage (RR 1.21; 95% CI 1.04 to 1.42; 21 trials, N = 4,507). There was insufficient evidence to support an effect of ESA on tumour response (fixed-effect RR 1.02; 95% CI 0.98 to 1.06, 15 trials, N = 5,012).

AUTHORS' CONCLUSIONS

ESAs reduce the need for red blood cell transfusions but increase the risk for thromboembolic events and deaths. There is suggestive evidence that ESAs may improve QoL. Whether and how ESAs affects tumour control remains uncertain. The increased risk of death and thromboembolic events should be balanced against the potential benefits of ESA treatment taking into account each patient's clinical circumstances and preferences. More data are needed for the effect of these drugs on quality of life and tumour progression. Further research is needed to clarify cellular and molecular mechanisms and pathways of the effects of ESAs on thrombogenesis and their potential effects on tumour growth.

The safety of switching between therapeutic proteins

INTRODUCTION

The approval of several biosimilars in the past years has prompted discussion on potential safety risks associated with switching to and from these products. It has been suggested that switching may lead to safety concerns. However, data is limited on the clinical effects of switching.

AREAS COVERED

In this review we provide an overview of data related to switching between human recombinant growth hormones, erythropoietins and granulocyte colony stimulating agents. We reviewed data from clinical trials, pharmacovigilance databases and an overview of the literature on the frequency of switching between these products. The review covers both switching between innovator products within the same product class and switching to and from biosimilars.

EXPERT OPINION

Data on the frequency of switching in clinical practice is scarce, but it seems most frequent for erythropoietins. We have found no evidence from clinical trial data or post marketing surveillance data that switching to and from different biopharmaceuticals leads to safety concerns.

Biosimilar recombinant human erythropoietins ("epoetins") and future erythropoiesis-stimulating treatments

INTRODUCTION

Recombinant human erythropoietin (rhEPO, epoetin) has prospered in the treatment of renal and chemotherapy-associated anemias. Since the patents of the original epoetins expired, biosimilars have been launched. Because these are not fully identical to the original products, non-clinical and clinical studies are necessary to show similarity with respect to quality, safety, and efficacy.

AREAS COVERED

The article summarizes experiences with EU-approved biosimilar epoetins. In particular, the issue of immunogenicity is considered. Neutralizing anti-EPO antibodies can cause pure red cell aplasia (PRCA). Further, a first view is offered on future erythropoiesis-stimulating therapies.

EXPERT OPINION

The term "biosimilar" should only be used for follow-on biopharmaceuticals approved under a defined regulatory pathway. The primary rationale for the therapy with biosimilars is cost saving. Two biosimilar epoetins are available in the EU that are used at the same dose(s) and dosing regimen(s) for indications of the reference product. Their advent has stimulated innovator companies to develop second-generation products with improved pharmacokinetic properties. EPO-mimicking peptides are a new therapeutic option. Other strategies focus on orally active chemical drugs that induce endogenous EPO production ("HIF stabilizers"). Epo gene transfer is also possible, but needs to be further explored with respect to efficacy and safety.