Future Evolution of Biosimilar Development by Application of Current Science and Available Evidence: The Developer's Perspective

Optimizing biosimilar development: current approaches to demonstrating pharmacokinetic and analytical similarity and a proposal for a single reference approach

OBJECTIVES

Many biosimilars have been approved in both the United States of America (U.S.A.) and European Union (EU). We aim to highlight how regulatory challenges and divergent requirements between both agencies exist.

METHODS

A comprehensive review of biosimilars approved by the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) was conducted. We aimed to highlight similarities and differences in approaches taken by the agencies regarding the use of non-local (i.e. non -US and non-EU) reference medicinal products in biosimilar development. A search of the six most frequent classes of biosimilars authorized (cutoff date: 12 June 2024) by these agencies were identified and their public assessment reports reviewed.

RESULTS

The review highlighted that pharmacokinetic (PK) bioequivalence studies are often replicated, the current process is inefficient and not entirely necessary when critical quality attributes are considered.

CONCLUSION

This article provides a comparative analysis of biosimilar approvals in EU and US regulatory agencies, focusing on non-local reference medicinal product (RMP) utilization and bioequivalence demonstration. The findings contribute to literature on biosimilar development and regulatory considerations, enhancing understanding of harmonization opportunities in biosimilar approval processes, potentially improving global access to high-quality, cost-effective biosimilars.

The changes necessary in the assessment of immunogenicity for the development of Biosimilars

Immunogenicity knowledge and the analytical capabilities to characterize molecules have evolved within the last decade. This creates opportunities in Biosimilar development by applying new strategies to demonstrate similarity between a proposed Biosimilar to its Reference.Within Immunogenicity Risk Assessment for Biosimilars, in silico and in vitro immunogenicity assessment tools are being evaluated for their utility in Biosimilar development. An ISI including an Immunogenicity Risk Assessment is recommended for Biosimilars within the dossier of licensing applications to facilitate the review by Health Authorities and to explain the immunogenicity in conjunction with analytical and clinical data. Operational aspects should also be considered to refine immunogenicity testing of Biosimilars, e.g. S/N ratio and singlicate sample analysis.

Efficacy, Safety, and Immunogenicity of SDZ-ADL, an Adalimumab Biosimilar, in Biologic-Naïve and Switched Patients with Immune-Mediated Inflammatory Diseases: A Literature Review

Sandoz-adalimumab (SDZ-ADL; Hyrimoz®, GP2017) is an adalimumab (ADL) biosimilar approved for the treatment of immune-mediated inflammatory diseases. Here, we review the available literature on SDZ-ADL from controlled and real-world evidence studies. A literature search was carried out to identify articles published up to July 2023 reporting data on efficacy, safety, immunogenicity, and treatment retention rates for SDZ-ADL. In randomized clinical trials, the efficacy, safety, and immunogenicity of SDZ-ADL were comparable to those observed for reference-adalimumab (ref-ADL) and not altered after single or multiple drug switches. Real-world studies confirmed the effectiveness and safety of treatment initiation with SDZ-ADL and of switching to SDZ-ADL from ref-ADL or from other ADL biosimilars. This literature review provides evidence that SDZ-ADL is as effective and safe as ref-ADL in both biologic-naïve and biologic-experienced patients.

Global Harmonization of Biosimilar Development by Overcoming Existing Differences in Regional Regulatory Requirements - Outcomes of a Descriptive Review

Global harmonization of biosimilar developmental requirements will facilitate development leading to increased patient and societal benefits. However, there are several technical and regulatory hurdles that must be addressed to harmonize the regulatory requirements in different countries and regions. At times, there is a requirement for use of locally sourced reference product, forcing biosimilar developers to repeat analytical or clinical comparability studies against reference product batches sourced from within a given country. While most health authorities no longer require comparative animal toxicology studies of the proposed biosimilar and reference product, these are still required in several countries, forcing biosimilar companies to conduct such studies or risk non-approval of their product. At times, different health authorities request different clinical study designs. In some jurisdictions there is a requirement to generate clinical data in local ethnic populations. Some health authorities require a hybrid label that combines clinical data from the reference biologic and the biosimilar, in the patient leaflet. Recommendations are provided to address each of these hurdles to facilitate global regulatory harmonization of biosimilars. Overcoming these barriers will ultimately increase patient access to these medicines in all regions while providing financial relief to healthcare systems.

The Path to Accessible Care: Development and Impact of Eculizumab Biosimilars for Paroxysmal Nocturnal Hemoglobinuria and Atypical Hemolytic Uremic Syndrome

Eculizumab, a humanized monoclonal antibody targeting complement C5, is the first approved drug for complement-mediated diseases and indicated to treat paroxysmal nocturnal hemoglobinuria, atypical hemolytic uremic syndrome, myasthenia gravis, and neuromyelitis optica spectrum disorder. The introduction of eculizumab has improved the prognosis of paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome to near-normal life expectancy and quality of life. Administration of eculizumab resulted in a rapid and sustained reduction in hemolytic activity and a consequent risk of thrombosis in paroxysmal nocturnal hemoglobinuria, and thrombotic microangiopathy in atypical hemolytic uremic syndrome, respectively. Nevertheless, many patients still have difficulty accessing eculizumab treatment because of its high costs. Biosimilars to reference eculizumab may increase patient access to treatment by creating market competition and eventually decreasing treatment costs. Clinical use of biosimilars in Europe in the last 15 years has demonstrated that they are as safe and effective as their reference products, and can also drive cost reductions and increase patients' access to treatment. This review aims to increase awareness about the importance of biosimilars of reference eculizumab and their entry for use in patients with paroxysmal nocturnal hemoglobinuria or atypical hemolytic uremic syndrome based on the accumulated experience of other previously approved biosimilars, and to provide an overview of the stringent biosimilar development pathway in general and the concept of extrapolation in particular.

Biosimilars and immunogenicity: a matter of concern?

INTRODUCTION

Biosimilars have transformed treatment modalities across various medical fields such as oncology, rheumatology, and immunology. Despite their potential for reducing healthcare costs, concerns persist regarding their ability to induce an immune response, which could affect efficacy and safety. This review critically evaluates the current evidence on the immunogenicity of biosimilars and discusses the regulatory frameworks guiding their approval and monitoring.

AREAS COVERED

This review includes studies from databases like Scopus, PubMed, Web of Science, and ScienceDirect, published up to April 2024. It explores the 'totality of the evidence' approach used by regulatory bodies like the FDA and EMA, detailing analytical, preclinical, and clinical assessments that ensure biosimilars' similarity to their reference products in terms of structure, function, and clinical outcomes. The review also addresses the challenges and limitations in current research methodologies and the implications of immunogenicity on therapeutic efficacy and patient safety.

EXPERT OPINION

While substantial evidence confirms the safety and efficacy of biosimilars, the review emphasizes the need for continuous regulatory vigilance and advanced methodologies in post-marketing surveillance to capture long-term immunogenicity data effectively. It advocates for integrating cutting-edge analytical techniques and personalized medicine to better manage immunogenic risks associated with biological therapies.

Evaluating biosimilars: safety, efficacy, and regulatory considerations in clinical studies

Biosimilars are a rapidly growing area of clinical research, yet they encounter significant challenges, especially in emerging markets where regulatory and clinical hurdles differ markedly from those in established regions like Europe and the US. This commentary addresses these unique challenges and offers new perspectives on the global adoption of biosimilars. It emphasizes the crucial role of real world evidence in supporting biosimilar approvals, an aspect often underrepresented in current literature. The commentary also provides a comparative analysis of the regulatory frameworks in China and Europe, highlighting how these differences shape biosimilar development and market approval processes. By focusing on the issues of indication extrapolation and immunogenicity, this commentary highlights the necessity of continuous real-world data collection to ensure the safety and efficacy of biosimilars across multiple indications. Our analysis enhances the understanding of biosimilar research and supports their broader adoption as safe, effective, and accessible healthcare solutions globally.

Trend Analysis of Regulatory Approvals for Generics and Biosimilars in Japan: 15 Years of PMDA During Fiscal Years 2009-2023

Generics and biosimilars play an important role in sustaining the universal healthcare insurance systems in Japan. The Pharmaceuticals and Medical Devices Agency (PMDA) reviews the quality, efficacy, and safety of generics and biosimilars for marketing authorization in Japan. Trend analyses of generics and biosimilars in terms of regulatory science have rarely been published. The PMDA and National Institute of Health Sciences websites were verified for generics and biosimilars, and information related to guidelines and notifications and the number of newly approved generics and biosimilars for fiscal year (FY) 2009-2023 were compiled. Approximately 1,900 and 200 generic drug products were approved in Japan in FY 2010 and 2023, respectively. The number of approved generic drug products has gradually decreased to one-tenth in the past 15 years. Overall, 35 biosimilars were approved in FY 2009-2023. The number of approved biosimilars has increased since FY 2017. This article reported a trend analysis of generics and biosimilars in terms of guidelines, notifications, and the number of applied and approved drug products in FY 2009-2023. Our primary goal is to increase patient access to affordable generics and biosimilars with assurance in appropriate quality.

Real world comparison of filgrastim to filgrastim-sndz in patients with chemotherapy-induced neutropenia

INTRODUCTION

There exists some apprehension by prescribers, healthcare providers, and other stakeholders regarding the real-world safety and effectiveness of biosimilars. While some of the apprehension is likely due to clinician knowledge gaps in the biosimilarity exercise, additional data (including those generated from the real-world) regarding safety and efficacy could reduce a clinician's perception of biosimilar uncertainty and can potentially increase biosimilar acceptance and uptake. The published literature is lacking regarding the real-world impact on healthcare costs and clinical outcomes when a single healthcare institution converts from filgrastim to filgrastim-sndz as its short-acting Granulocyte Colony Stimulating Factor (GCSF), especially within diverse populations and indications not explicitly studied through the registration trials. Specifically, both filgrastim and filgrastim-sndz possess FDA-approved indications within patients with hematologic malignancies receiving high-dose chemotherapy and in those undergoing bone marrow transplantation. As a biosimilar to filgrastim, the FDA did not require prospective, randomized controlled trials to obtain these indications for filgrastim-sndz. The purpose of this study is to describe real-world healthcare resource costs, utilization patterns, and clinical outcomes in patients with hematologic malignancies who received filgrastim-sndz or filgrastim to support neutrophil recovery following chemotherapy (i.e., induction or consolidation) or a bone marrow transplant (BMT) at Yale New Haven Hospital (YNHH).

METHODS

A total of 148 patients were identified and met the following criteria: at least 18 years old, Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2, absence of fever or infection, newly diagnosed acute myeloid leukemia or newly post-bone marrow transplant and received filgrastim-sndz (Zarxio®) or reference filgrastim (Neupogen®).

RESULTS

Healthcare resource utilization outcomes were compared between biosimilar and reference filgrastim using descriptive statistics. There were no major differences between either cohort, including duration of hospitalization, the number of overall emergency room visits and additional hospital admissions with a primary diagnosis of febrile neutropenia or neutropenia within 30 days post-discharge from initial hospital admission, time to neutrophil recovery following GCSF support, and the incidence and duration of both fever and febrile neutropenia. The total cost based on treatment of all patients in each arm differed significantly with filgrastim-sndz being the most cost-effective choice.

CONCLUSION

filgrastim-sndz significantly reduced healthcare utilization costs compared to reference filgrastim with similar effect on absolute neutrophil count, incidence of fever, and febrile neutropenia.

Survey of Data Package and Sample Size of Comparative Clinical Studies for Biosimilar Developments from PMDA Assessments

BACKGROUND

The Japanese biosimilar guideline requires that the sponsors conduct clinical studies such as comparative pharmacokinetic (PK), pharmacodynamic (PD), or efficacy studies. In each biosimilar development, the sponsors consider the clinical data package, and thus clinical data packages vary among biosimilar developments.

OBJECTIVES

The aim of this study was to elucidate the clinical data packages for the biosimilars approved in Japan. The details of clinical data packages and sample size for the regulatory approvals of biosimilars in Japan was reported.

METHODS

We surveyed the clinical data packages and sample size based on the Pharmaceuticals and Medical Devices Agency (PMDA) website review reports between 2009 and 2023.

RESULTS

Twenty-four biosimilars have been approved based on the comparative PK and efficacy studies, 10 biosimilars have been approved based on the comparative PK/PD study, and one biosimilar has been approved based on the comparative efficacy study. Regarding the sample size, comparative PK studies were conducted in healthy volunteers or patients for up to 300 cases, although the majority enrolled only 1-100 cases (68.1%, 32/47). Comparative PD studies enrolling 1-30, 31-60, and 61-90 cases totaled 4, 7, and 4 cases, respectively. Finally, comparative efficacy studies enrolling 1-300, 301-600, and 601-900 totaled 6, 10, and 11 cases, respectively. In particular, the oncology and rheumatology areas were the first and second disease areas recruiting 601-900 patients.

CONCLUSION

Large numbers of patients were enrolled to conduct a comparative efficacy study. Efficient biosimilar development should be considered on the basis of the accumulation of scientific understanding of comparable features of biosimilars and their development.

Impact of Excipient Extraction and Buffer Exchange on Recombinant Monoclonal Antibody Stability

The foundation of a biosimilar manufacturer's regulatory filing is the demonstration of analytical and functional similarity between the biosimilar product and the pertinent originator product. The excipients in the formulation may interfere with characterization using typical analytical and functional techniques during this biosimilarity exercise. Consequently, the producers of biosimilar products resort to buffer exchange to isolate the biotherapeutic protein from the drug product formulation. However, the impact that this isolation has on the product stability is not completely known. This study aims to elucidate the extent to which mAb isolation via ultrafiltration-diafiltration-based buffer exchange impacts mAb stability. It has been demonstrated that repeated extraction cycles do result in significant changes in higher-order structure (red-shift of 5.0 nm in fluorescence maxima of buffer exchanged samples) of the mAb and also an increase in formation of basic variants from 19.1 to 26.7% and from 32.3 to 36.9% in extracted innovator and biosimilar Tmab samples, respectively. It was also observed that under certain conditions of tertiary structure disruptions, Tmab could be restabilized depending on formulation composition. Thus, mAb isolation through extraction with buffer exchange impacts the product stability. Based on the observations reported in this paper, we recommend that biosimilar manufacturers take into consideration these effects of excipients on protein stability when performing biosimilarity assessments.

Long-Term Real-World Post-approval Safety Data of Multiple Biosimilars from One Marketing-Authorization Holder After More than 18 Years Since Their First Biosimilar Launch

BACKGROUND

Biosimilars are additional treatment options that are approved based on robust analytical and clinical comparisons with their reference biologic. At the time of initial approval, the full safety profile of a biosimilar is inferred from the reference biologic. Nonetheless, there are still lingering concerns related to the long-term safety of biosimilars. Therefore, we reviewed the post-approval pharmacovigilance data for eight marketed biosimilars from one Marketing Authorization Holder (MAH) to summarize their safety experience in a real-world setting for up to 18 years since their first biosimilar launch.

METHODS

Post-approval cumulative patient exposure and safety experience for eight Sandoz biosimilars [adalimumab (Hyrimoz®), epoetin alfa (Binocrit®), etanercept (Erelzi®), filgrastim (Zarzio®), infliximab (Zessly®), pegfilgrastim (Ziextenzo®), rituximab (Rixathon®), and somatropin (Omnitrope®)] was summarized based on the available pharmacovigilance data from Periodic Safety Update Reports (PSURs) and the corresponding health authority-authored PSUR assessment reports, where available, as of 31 January 2023. Exposure to all biosimilars was calculated in patient treatment days (PTD) except for rituximab, which was expressed in number of patient doses (PD).

RESULTS

The combined post-approval cumulative exposure to seven out of the eight marketed Sandoz biosimilars was more than 1.3 billion PTD and for rituximab more than 1.8 million PD. Overall, a critical analysis of the cumulative safety data of all eight Sandoz biosimilar PSURs concluded that the overall benefit-risk profile of each remains favorable and is consistent with the respective reference biologics.

CONCLUSIONS

This is one of the largest reviews of post-approval biosimilar pharmacovigilance data to date by one MAH. The real-world experience of all eight marketed Sandoz biosimilars for up to 18 years demonstrates that Sandoz biosimilars can be used as safely as their respective reference biologics. Therefore, patients and healthcare providers can be confident in the clinical benefit and safety of Sandoz biosimilars. It is reasonable to believe that similar conclusions about safety may be reached for other biosimilars developed and approved to the high standards as are already in place by major health authorities such as the European Medicines Agency (EMA) and the US Food and Drug Administration (FDA). The long-term safety of biosimilars demonstrated here provides strong support for the concept of biosimilarity.

Biosimilars in the treatment of rheumatoid arthritis: a pharmacokinetic overview

INTRODUCTION

As of May 2023, 19 and 18 biosimilars have been approved for the treatment of rheumatoid arthritis (RA) by the European Medicines Agency (EMA) and United States Food and Drug Administration (US FDA) respectively.

AREA COVERED

Pharmacokinetic results of phase 1 studies of approved biosimilars were reviewed by systematic literature search. The impact of immunogenicity on the pharmacokinetic data and clinical response was assessed, and the potential benefit of monitoring serum concentrations of biologic drugs is discussed. The advantage of subcutaneous CT-P13 (an infliximab biosimilar) in clinical practice is reviewed.

EXPERT OPINION

Biosimilars are approved based on the totality of evidence including comparable physiochemical properties, PK / PD profiles, and clinical efficacy and safety to the originator. To utilize biosimilars more effectively, physicians should be aware of the utility of combination DMARD therapy to reduce immunogenicity and maintain efficacy and PK profile. PK monitoring, however, is not currently recommended in clinical practice. CT-P13 subcutaneous (SC) is the first SC infliximab used for treatment of RA patients. Based on data from clinical studies and the real world, SC-infliximab is an attractive therapeutic option compared to IV formulations of infliximab based on its efficacy, pharmacokinetics, patient-reported outcomes, and safety profile.