The End of Phase 3 Clinical Trials in Biosimilars Development?

Monoclonal antibody biosimilars for cancer treatment

Monoclonal antibodies are important cancer medicines. The European Medicines Agency (EMA) approved 48 and the Food and Drug Administration (FDA) 56 anticancer monoclonal antibody-based therapies. Their high prices burden healthcare systems and hamper global drug access. Biosimilars could retain costs and expand the availability of monoclonal antibodies. In Europe, five rituximab biosimilars, six trastuzumab biosimilars, and eight bevacizumab biosimilars are available as anti-cancer drugs. To gain insight into the biosimilar landscape for cancer treatment, we performed a literature search and analysis. In this review, we summarize cancer monoclonal antibodies' properties crucial for the desired pharmacology and point out sources of variability. The analytical assessment of all EMA-approved bevacizumab biosimilars is highlighted to illustrate this variability. The global landscape of investigational and approved biosimilars is mapped, and the challenges for access to cancer biosimilars are identified.

A Retrospective Analysis of the Potential Impact of Differences in Aggregates on Clinical Immunogenicity of Biosimilars and their Reference Products

Aggregates, in particular high molecular weight species (HMWs), have been linked to increased immunogenicity. The current understanding on the impact of HMWs is mainly based on in vitro and nonclinical studies and there are only limited data available associating differences in HMWs in marketed monoclonal antibodies (mAbs) to clinical outcomes. Biosimilars offer a unique opportunity to study the potential association between quality parameters and clinical outcomes. We performed a retrospective evaluation to investigate the association between HMW content and reported antidrug-antibody (ADA) incidence in 30 full-length biosimilar mAbs approved in the European Union and the United States. Information for HMW content and ADA incidence were collected from publicly available sources. Differences in HMW content between biosimilars and their reference products (RPs) ranged from -0.75 to 1.65% with slightly higher differences observed in antineoplastic products as compared with immunosuppressant products. The difference in the ADA incidence between the RP and the biosimilar for the programs studied ranged from -11.0 to 18.5%. No association was observed between differences in HMW content and reported ADA incidence, in neither phase I nor phase III studies. Our results show that the limited differences in the content of HMWs between marketed biosimilars and reference mAbs were not associated with differences in reported immunogenicity, determined as incidence of ADAs and neutralizing ADAs in comparative clinical studies.

The landscape of biosimilars in Saudi Arabia: preparing for the next decade

INTRODUCTION

The government of the Kingdom of Saudi Arabia (KSA) has developed a well-defined strategy to restructure the health sector and operate on value-based principles. Biosimilars are a viable option for increasing accessibility while lowering health-care costs.

AREAS COVERED

We describe the current and future biosimilar landscape in KSA. We discuss the growth of the biosimilar market, the regulatory approval process, biosimilar adoption, and the potential impact on health-care systems and patient outcomes.

EXPERT OPINION

The biosimilar market in KSA is expanding and expected to continue this trajectory in the coming decade. The growth of the market is influenced by the KSA health transformation initiative, the well-defined regulatory framework for biosimilars set by the Saudi Food and Drug Authority (SFDA), and the adoption of biosimilars by health-care providers. Overall, the biosimilar regulation is evolving and the future of biosimilars looks promising in KSA. Biosimilars offer a more cost-effective alternative, which can help to expand access to more treatment options for patients and contribute to cost saving for the health-care system.

Taking the individual bias out of examining comparability of biosimilars: A case study on monoclonal antibody therapeutics

Biosimilar manufacturers need to perform analytical and functional similarity assessments against the reference product. Successful demonstration allows for an abbreviated clinical path, thereby translating to affordable biosimilars. Current practices for regulatory concurrence on analytical similarity data are based on chart visualization and open to individual (human) bias. Here, we present a novel, chemometric approach for assessing biosimilarity that aims to simplify assessment and eliminate individual bias from decision making through application of weighted principal component analysis. Through the proposed approach, chemical information across the analytical characterization platform and drug products can be collated into a single plot for quantitative biosimilarity assessment. The proposed one-plot analysis offers a holistic visualization of 1) inter-product variability (w.r.t reference product) in cases where multiple batches per product have been investigated and 2) intra-product variability for each critical quality attribute (CQA) wherein information from orthogonal tools can be incorporated within the same plot. This allows for numerical grading of similarity for biosimilars of any given reference product. Although the proposed statistical approach is novel, it builds on standardized measures of CQA, criticality, and analytical procedures, thus making this approach easy to incorporate within the existing regulatory framework.

The Role of PD Biomarkers in Biosimilar Development - To Get the Right Answer One Must First Ask the Right Question

The potential for pharmacodynamic (PD) biomarkers to improve the efficiency of biosimilar product development and regulatory approval formed the premise for the virtual workshop Pharmacodynamic Biomarkers for Biosimilar Development and Approval hosted by the US Food and Drug Administration (FDA) and Duke Margolis, September 2021. Although the possibility of PD biomarkers replacing the to-date routine comparative phase III confirmatory study currently expected by the FDA was discussed, the motivation and feasibility for biosimilar sponsors developing such markers and the regulatory risks entailed largely were not. Even more fundamental is the already established greater comparative value of the pharmacokinetic (PK) study as the most sensitive clinical assay for detecting subtle differences between two products. Consequently, the comparative analytical assessment and the head-to-head PKs will have already answered the core questions as to the biosimilarity of the candidate product to its reference. No further actionable information is obtained with either a PD study or a comparative clinical phase III study even as they may provide some reassurance of what is already known. When a suitable PD biomarker is available for the originator reference product they have already been used for biosimilar development. We must carefully consider the core requirements and timelines inherent in biosimilar development and how they occur in parallel rather than in the series we see for originator products. In order to improve the efficiency of biosimilar development, we need to ask the right questions based on a full understanding of how biosimilars have been developed to date and can be in the future.

Biosimilars: Harmonizing the Approval Guidelines

Biosimilar approval guidelines need rationalization and harmonization to remove the inconsistencies and misconceptions to enable faster, safer, and more cost-effective biosimilars. This paper proposes a platform for a model guideline based on the scientific evaluation of the regulatory filings of the 130+ products approved in the US, UK, and EU and hundreds more in the WHO member countries. Extensive literature survey of clinical data published and reported, including Clinicaltrials.gov, a review of all current guidelines in the US, UK and EU, and WHO, and detailed discussions with the FDA have confirmed that removing the animal and clinical efficacy testing and fixing other minor approaches will enable the creation of a harmonized guideline that will best suit an ICH designation.

Biosimilar development and review process in the BRICS-TM countries: proposal for a standardized model to improve regulatory performance

OBJECTIVES

The current study is aimed at proposing a standardized regulatory model for biosimilar development and approval for adoption by BRICS-TM agencies, based on evaluation of regulatory guidelines and potential solutions to challenges.

METHODS

An established validated questionnaire was used and the recommendations were collated. Propositions deemed critical for improving the regulatory pathway for biosimilar development were synthesized to design a new regulatory model.

RESULTS

The key areas for improvement in BRICS-TM countries were: effective implementation of a step-wise approach; adoption of science-based regulatory evaluation for clinical efficacy studies and acceptance of analytical comparability studies in lieu of confirmatory clinical trials; a streamlined biosimilar development program for RBP sourcing; regulatory reliance for joint or shared review of the applications; and enhanced transparency and communication between the regulatory agencies and biosimilar developers. Based on these identified critical aspects, a simplified and standard regulatory model was developed to enable standardization of biosimilar guidelines across BRICS-TM countries for a common development program.

CONCLUSIONS

Effective implementation of the proposed standardized model for biosimilar development and approval processes across the BRICS-TM agencies will eliminate unwarranted studies, reduce the development costs and enhance process efficiency thereby expediting patients' access to new affordable biosimilar medicines.

Regulatory Evaluation of Biosimilars: Refinement of Principles Based on the Scientific Evidence and Clinical Experience

The World Health Organization (WHO) guidelines on evaluation of similar biotherapeutic products (SBPs; also called biosimilars) were adopted by the WHO Expert Committee on Biological Standardization (ECBS) in 2009. In 2019, the ECBS considered that a more tailored and potentially reduced clinical data package may be acceptable in cases where this was clearly supported by the available scientific evidence. The goal of this publication is to review the current clinical experience and scientific evidence and to provide an expert perspective for updating the WHO guidelines to provide more flexibility and clarity. As the first step, the relevant guidelines by other regulatory bodies were reviewed in order to identify issues that might help with updating the WHO guidelines. Next, a literature search was conducted for information on the long-term efficacy, safety, and immunogenicity of biosimilars to identify possible long-term problems. Finally, a search for articles concerning the role of clinical studies in the benefit-risk evaluation of biosimilars was conducted. The analysis of other guidelines suggested that the WHO guidelines may need more emphasis on the importance of the state-of-the-art physicochemical and structural comparability exercise and in vitro functional testing. The use of "foreign" reference product will also need clarifications. The value of in vivo toxicological tests in the development of biosimilars is questionable, and the non-clinical part needs revisions accordingly. The concepts of "totality of evidence," "stepwise development," and "residual uncertainty" were applied in the evaluation of the clinical sections of the guideline. The review of long-term safety and efficacy demonstrated the robustness of the current biosimilar development concept. The analysis of the roles of different development phases suggested that the large efficacy, safety, and immunogenicity studies are, in most cases, redundant. The residual uncertainty of safety, immunogenicity, and efficacy of biosimilars that has shaped the current regulatory guidelines is now substantially reduced. This will allow the re-evaluation of the non-clinical and clinical requirements of the current WHO main guideline. The shift of the relative impact of the development phases towards physico-chemical and in vitro functional testing will provide a relief to the manufacturers and new challenges to the regulators.

Assessment of Functional Characterization and Comparability of Biotherapeutics: a Review

The development of monoclonal antibody (mAb) biosimilars is a complex process. The key to their successful development and commercialization is an in-depth understanding of the key product attributes that impact safety and efficacy and the strategies to control them. Functional assessment of mAb is a crucial part of the comparability of biopharmaceutical drugs. The development of a relevant and robust functional assay requires an interdisciplinary approach and sufficient flexibility to balance regulatory concerns as well as dynamics and variability during the manufacturing process. Although many advanced tools are available to study and compare the potency and bioactivity of the protein, most of these techniques suffer from major shortcomings that limit their routine use. These include the complexity of the task, establishment of the relevance of the chosen method with the mechanism of action (MOA) of the biosimilar, cost and extended time of analysis, and often the ambiguity in interpretation of the resulting data. To overcome or to address these challenges, the use of multiple orthogonal state-of-the-art techniques is a necessary prerequisite.

Evolving Biosimilar Clinical Requirements: A Qualitative Interview Study with Industry Experts and European National Medicines Agency Regulators

BACKGROUND

A biosimilar is a biological medicine highly similar to another already approved biological medicine (reference product). The availability of biosimilars promotes competition and subsequently lower prices. Changing the current biosimilar clinical comparability trial requirements may lead to lower biosimilar development costs that potentially could increase patients' access to biologics.

OBJECTIVE

The aim was to determine the perceptions of industry and medicines agency regulators regarding the value, necessity, and future developments of the European biosimilar clinical comparability trial requirements for establishing biosimilarity.

METHODS

Semi-structured interviews were conducted with eight European national medicines agency regulators and 17 pharmaceutical company employees or consultants with experience in biologics between September 2018 and August 2019. Data were subjected to content analysis.

RESULTS

In general, the participants expected that clinical comparability trial requirements will continue to be reduced, in particular based on advancements in analytical testing and knowledge generated from prior biosimilar approvals. However, there are also competing issues at play, such as competition, physician's trust, and ethical considerations. Participants also reported that any new initiative to reduce or waive biosimilar clinical requirements needs to be scientifically sound and could potentially lower biosimilar development costs.

CONCLUSION

The main findings are that biosimilar clinical comparability trial requirements are likely to change in the near future. Clarity is needed on how to ensure adequate correlation between physicochemical data, pharmacokinetic/pharmacodynamic studies, and the drugs' performance in the clinic, as well as how to continue sufficient immunogenicity assessment. Obtaining this clarity can facilitate regulatory assessment of the next biosimilars.

The Path Towards a Tailored Clinical Biosimilar Development

Since the first approval of a biosimilar medicinal product in 2006, scientific understanding of the features and development of biosimilar medicines has accumulated. This review scrutinizes public information on development programs and the contribution of the clinical studies for biosimilar approval in the European Union (EU) and/or the United States (US) until November 2019. The retrospective evaluation of the programs that eventually obtained marketing authorization and/or licensure revealed that in 95% (36 out of 38) of all programs, the comparative clinical efficacy studies confirmed similarity. In the remaining 5% (2 out of 38), despite meeting efficacy outcomes, the biosimilar candidates exhibited clinical differences in immunogenicity that required changes to the manufacturing process and additional clinical studies to enable biosimilar approval. Both instances of clinical differences in immunogenicity occurred prior to 2010, and the recurrence of these cases is unlikely today due to state-of-the-art assays and improved control of process-related impurities. Biosimilar candidates that were neither approved in the EU nor in the US were not approved due to reasons other than clinical confirmation of efficacy. This review of the development history of biosimilars allows the proposal of a more efficient and expedited biosimilar development without the routine need for comparative clinical efficacy and/or pharmacodynamic studies and without any compromise in quality, safety, or efficacy. This proposal is scientifically valid, consistent with regulation of all biologics, and maintains robust regulatory standards in the assessment of biosimilar candidates. Note: The findings and conclusion of this paper are limited to biosimilar products developed against the regulatory standards in the EU and the US.

In vitro functional characterization of biosimilar therapeutic antibodies

The key factor in successful development and marketing of biosimilar antibodies is a deep understanding of their critical quality attributes and the ability to control them. Comprehensive functional characterization is therefore at the heart of the process and is a crucial part of regulatory requirements. Establishment of a scientifically sound molecule-specific functional in vitro assay panel requires diligent planning and high flexibility in order to respond to both regulatory requirements and the ever-changing demands relevant to the different stages of the development and production process. Relevance of the chosen assays to the in vivo mechanism of action is of key importance to the stepwise evidence-based demonstration of biosimilarity. Use of a sound interdisciplinary approach and orthogonal state-of-the-art techniques is also unavoidable for gaining in-depth understanding of the biosimilar candidate. The aim of the present review is to give a snapshot on the methodic landscape as depicted by the available literature discussing the in vitro techniques used for the functional characterization of approved biosimilar therapeutic antibodies. Emerging hot topics of the field and relevant structure-function relationships are also highlighted.

[Biosimilars in the European Union: current situation and challenges]

Biosimilars are medicinal products that are highly similar to approved biopharmaceuticals. Biosimilars enable patient access to biological therapies that would otherwise be restricted or delayed due to cost reasons. After the successful introduction of low-molecular biosimilars in 2006, highly complex monoclonal antibodies have also been available since 2013 as biosimilars for treating autoimmune diseases and oncologic indications. In principle, the biosimilar concept can be applied to all well-characterized biologicals; in the future, blood clotting factors or drugs containing nucleic acids, such as DNA or RNA gene therapy or mRNA vaccines, will also be an option for biosimilar development.In some instances, biosimilarity can be demonstrated by physicochemical and functional similarity, and additional comparative clinical efficacy and safety studies have been considered no longer necessary for several product categories in recent years. Switching a patient from a reference drug to a biosimilar or from one biosimilar to another (interchangeability) has so far been considered harmless. Since February 2020, there has been a provisional decision in Germany that patients should be switched according to an economic prescription method. Further scientific findings on the interchangeability of biosimilars and experiences with the supply practices of biosimilars should be collected and evaluated.In this article, the current situation regarding marketing authorizations of biosimilars in the European Union is reviewed. The role of clinical trials for biosimilars is presented, and challenges of biosimilar development and views on interchangeability are discussed.

Streamlined approval of biosimilars: moving on from the confirmatory efficacy trial

Licensing of biosimilars is essential to promote patient access to 21st-century biological medicines. Regulatory approval of biosimilars is based on the totality of evidence from a head-to-head comparison with reference products (RPs). A clinical efficacy trial is usually required, but this is increasingly questioned. Based on a thorough review of biosimilar applications in the European Union (EU), we conclude that in-depth knowledge of the reference product, allied with high-performing analytical tools, largely predicts clinical comparability, subject to confirmation by a comparative pharmacokinetic (PK) trial. We provide a blueprint for a biosimilar pathway that reduces the need for clinical efficacy trials in exceptional cases, together with qualifying criteria and requirements for streamlined assessment to expedite wider access to affordable biological medicines.

Understanding the Role of Comparative Clinical Studies in the Development of Oncology Biosimilars

Biosimilars have the potential to broaden patient access to biologics and provide cost savings for health care systems. During the development of a biosimilar, data that directly compare the proposed biosimilar with the reference product are required. Such comparative data are generated in a stepwise hierarchical process that begins with extensive laboratory-based structural analyses and functional assays. This initial analytical phase serves as the foundation for the demonstration of biosimilarity and is followed by nonclinical in vivo testing (if required) and then clinical evaluation, including a comparative pharmacokinetics/pharmacodynamics study that is usually conducted in healthy volunteers. The development program typically culminates with a comparative clinical efficacy study. The aim of this study is to confirm clinical equivalence of the potential biosimilar and reference product on the basis of prespecified margins, using a study population and efficacy end point that are sufficiently sensitive for detecting potential product-related differences. Such studies also include detailed analyses of safety as well as evaluation of immunogenicity. As biosimilars become more widely available in oncology, especially with recent regulatory approvals of rituximab, trastuzumab, and bevacizumab biosimilars, it is critically important that clinicians understand how the comparative clinical study differs from a traditional phase III efficacy and safety study in the development of a novel biologic originator product. Here, we review the role of comparative clinical studies in biosimilar development, with a focus on trials conducted to support approved trastuzumab biosimilars. We discuss the study populations and end points used, extrapolation of indications, and the confirmatory nature of these studies within the totality of evidence supporting biosimilarity.

Evaluation of pharmacokinetics and safety with bioequivalence of Amlodipine in healthy Chinese volunteers: Bioequivalence Study Findings

Background and Objective

Amlodipine, a main series of L‐type calcium channel blockers (CCBs), exerts potent antihypertensive effects. The aim of this trial was to explore the pharmacokinetics (PK) and safety with bioequivalence of orally administered Amlodipine provided by two sponsors in healthy volunteers (HVs).

Methods

Two separate randomized, open‐label, single‐dose, crossover‐design studies were conducted: a fasting study (n = 24) and a fed study (n = 24). In each study, HVs were randomized to Fangming Pharmaceutical Group (Test, T) followed by NORVASC^® (Reference, R), or vice versa. Each study subject received a 5‐mg Amlodipine tablet with a 15‐day washout. The plasma concentrations of Amlodipine were measured using a LC‐MS/MS method, and PK parameters were determined by noncompartmental model.

Results

Forty‐eight healthy volunteers were enrolled. And overall demographics were as follows: the fasting study: female (n = 16/24), age (18‐54 years), weight (47‐76 kg), and BMI (19.5‐26.0). The fed study: female (n = 16/24), age (20‐49 years), weight (45.5‐69 kg), and BMI (19.1‐25.0). All PK endpoints met the pre‐specific criteria for PK equivalence. In fasting subjects, the maximum plasma concentration (C_max) was 3.881 ± 0.982 ng/mL at 6 hours (median) of sponsor T, and 4.042 ± 1.147 ng/mL at 6 hours (median) of sponsor R. In fed subjects, C_max was 3.312 ± 0.789 ng/mL at 6 hours (median) of sponsor T, and 3.392 ± 0.902 ng/mL at 5 hours (median) of sponsor R. Both fasting and fed studies achieved a plausible bioequivalence.

Conclusions

Amlodipine is well tolerated and have a favorable safety profile. The observed adverse events were mild (the severity was assessed according to the Common Terminology Criteria for Adverse Events [version CTCAE4.03]) and all of them were recovered without severe sequences. And the bioequivalence is achieved under fasting and fed conditions, supporting the demonstration of biosimilarity.

Clinical evidence supporting the marketing authorization of biosimilars in Europe

PURPOSE

To review the marketing authorization of biosimilars and provide a critical analysis of the pivotal trials supporting their approval by the European Medicines Agency (EMA).

METHODS

EMA website to identify the biosimilars approved up to July 2019 and the European Public Assessment Report for information on pivotal trial design, duration, intervention and control, primary outcome, data on immunogenicity, and comparability margins.

RESULTS

The EMA has approved 55 biosimilars (62% in 2017-2019) of 16 biologic products, used in several clinical indications. Some biosimilars were licensed as multiple products, with different commercial names, by the same or different companies. The comparability exercise and subsequent approval of 49/55 (89%) biosimilars were based on one or more pivotal phase III trials testing their clinical efficacy. In all, biosimilars were approved on the basis of 55 trials, mostly phase III (42/55, 76%) assessing clinical efficacy; these were mainly equivalence trials (31/55, 56%). The pivotal phase III trials assessed surrogate measures of clinical effect, and 71% reported immunogenicity data.

CONCLUSION

Analysis of the approval of biosimilars in Europe depicts a complex and heterogeneous scenario. The requirement for showing similarity in terms of clinical efficacy and safety provides a robust demonstration of comparable clinical outcomes but lays a burden on biosimilar manufacturers and may delay the introduction of the drugs. The development, licensing, and monitoring of biosimilars would benefit from new strategies to accelerate access to these drugs while reducing uncertainties about their use in practice.

Analysis of Pharmacokinetic and Pharmacodynamic Parameters in EU- Versus US-Licensed Reference Biological Products: Are In Vivo Bridging Studies Justified for Biosimilar Development?

BACKGROUND

Bridging studies are mandatory in the EU and USA if the reference biological product used in the biosimilar comparability exercise is foreign sourced. However, it has been argued that the duplication of bridging studies may limit biosimilar development.

OBJECTIVE

The aim of the study was to explore whether it is necessary to conduct pharmacokinetic (PK)/pharmacodynamic (PD) bridging studies for biosimilars. This study examines similarities and differences between EU- and US-licensed reference biological products, based on literature-reported PK and/or PD data.

METHODS

We searched PubMed, Drugs@FDA, and European Medicines Agency (EMA) databases to identify biosimilar bridging studies designed to evaluate similarities between EU- and US-licensed reference biological products. PK and/or PD parameters were retrieved; the ratio of the parameter value of the EU-licensed product to that of the US-licensed product and its corresponding 90% confidence intervals (CIs) were calculated. Similarity was declared if the 90% CIs for the ratios of the PK or PD parameters were within the range of 80-125%.

RESULTS

Thirty-one bridging studies were identified for 11 biosimilars, including adalimumab (n = 10), bevacizumab (n = 4), epoetin alfa (n = 1), etanercept (n = 2), filgrastim (n = 1), infliximab (n = 3), insulin glargine (n = 1), insulin lispro (n = 1), PEGfilgrastim (n = 2), rituximab (n = 2), and trastuzumab (n = 4). Most studies showed PK and/or PD similarities between the EU- and US-licensed reference biological products. However, among the 31 studies, only three studies (accounting for two biologics, PEGfilgrastim and adalimumab) showed dissimilarity between the EU and US reference products. Although one bridging study on PEGfilgrastim (Sandoz) indicated dissimilar PKs (maximum observed plasma concentration [C_max] and area under the concentration-time curve [AUC]) between the reference products, the other study (Mylan) demonstrated similar PK. Moreover, two of ten studies involving adalimumab failed to demonstrate similarities between the reference products. However, for both cases, PK similarities were later confirmed in the follow-up bridging studies with larger sample sizes.

CONCLUSION

Our analysis reveals that, in most cases, the reference biological products originated from the EU and those from the USA are almost indistinguishable in terms of PK/PD properties. Additional in vivo bridging studies between reference products from different global regions may not be required if similar physicochemical and structural properties are evident in vitro.

The Case for Disclosure of Biologics Manufacturing Information

Ten years after the enactment of the Biologics Price Competition and Innovation Act (BPCIA), competition in biologics markets remains scant and far from sufficient for lowering prices of biologics to the level of 80-90% price drops seen in generic drug markets. This reality is not a result of one or two cardinal reasons, but many. If lowering the price of biologics is the goal and competition is the means by which we seek to achieve that goal, then there does not seem to be a quick fix to address all of the many impediments to competition that plague biologics markets. Yet, certain changes to how the Food and Drug Administration (FDA) evaluates and approves biologics may go a long way toward the creation of meaningful competition in biologics markets. One such change would be making original biologics' manufacturing information available to follow-on manufacturers. As recognized by several commentators, access to biologics manufacturing information is key to increasing competition in biologics markets. Without access to such information, making follow-on biologics is difficult and expensive, if not outright impossible. This is expected to be especially true for the highly anticipated class of interchangeable biologics, none of which has been approved by the FDA to date. Yet, it has long been the position of the brand-name pharmaceutical industry (Industry) that biologics manufacturing information is proprietary and, thus, may not be shared. Congress has subscribed to the Industry's position, prohibiting the FDA from disclosing regulatory filings submitted by developers of original biologics, including manufacturing information, to third parties. That prohibition not only undermines competition in biologics markets, but is also wasteful, potentially unethical, and poses unnecessary risks to the health and safety of patients. This article makes the case for FDA sharing of original biologics manufacturing information with follow-on biologics developers. It is informed by the similar legal and commercial circumstances in the area of pesticides and the regulatory regime established by Congress in the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), which is administered by the Environmental Protection Agency (EPA). The article reviews the FIFRA regime, including its upholding as constitutional by the United States Supreme Court, and then examines its applicability to the area of biologics. The article concludes with a proposal for a similar regime to be incorporated into the pathway for approval of follow-on biologics as a means of increasing competition in biologics markets.

An Efficient Development Paradigm for Biosimilars

The current development paradigm for biosimilars required by regulators in highly regulated jurisdictions is derived from the development of novel drugs and is unnecessarily burdensome and inefficient. It requires the accumulation of data from analytical, nonclinical (including in vivo studies in some jurisdictions), and clinical studies (including powered efficacy studies in most cases); this paradigm is known as 'totality of evidence' (ToE) and does not admit a conclusion of biosimilarity from analytical data alone. The record of biosimilar approvals in these jurisdictions shows that no biosimilar candidate that has been found highly similar to its reference in analytical and pharmacokinetic studies has failed to be approved. We propose a new paradigm ('confirmation of sufficient likeness', CSL) that emphasizes the demonstration of analytical resemblance between the biosimilar candidate and its reference, and permits the conclusion of biosimilarity upon this basis. CSL does not entail bridging studies between reference products, in vivo nonclinical studies, or powered efficacy studies and is, therefore, substantially more efficient than ToE while maintaining equivalent scientific rigor. Such efficiency will contribute to the attractiveness as well as the sustainability of biosimilars as a therapeutic modality.

The Breakthrough of Biosimilars: A Twist in the Narrative of Biological Therapy

The coming wave of patent expiries of first generation commercialized biotherapeutical drugs has seen the global market open its doors to close copies of these products. These near perfect substitutes, which are termed as “biosimilars”, do not need to undergo intense clinical trials for their approval. However, they are mandated to produce identical similarity from their reference biologics in terms of clinical safety and efficacy. As such, these biosimilar products promise to foster unprecedented access to a wide range of life-saving biologics. However, seeing this promise be fulfilled requires the development of biosimilars to be augmented with product trust, predictable regulatory frameworks, and sustainable policies. It is vital for healthcare and marketing professionals to understand the critical challenges surrounding biosimilar use and implement informed clinical and commercial decisions. A proper framework of pharmacovigilance, education, and scientific exchange for biologics and biosimilars would ensure a dramatic rise in healthcare access and market sustainability. This paper seeks to collate and review all relevant published intelligence of the health and business potential of biosimilars. In doing so, it provides a visualization of the essential steps that are required to be taken for global biosimilar acceptance.

PF-06881893 (Nivestym™), a Filgrastim Biosimilar, Versus US-Licensed Filgrastim Reference Product (US-Neupogen®): Pharmacokinetics, Pharmacodynamics, Immunogenicity, and Safety of Single or Multiple Subcutaneous Doses in Healthy Volunteers

BACKGROUND

Three comparative clinical studies assessed the pharmacokinetics (PK), pharmacodynamics (PD), immunogenicity and safety of PF-06881893 (filgrastim-aafi; Nivestym™), a filgrastim biosimilar, versus US-licensed reference product (filgrastim; US-Neupogen^®) in healthy volunteers (HVs).

METHODS

Two separate open-label, crossover-design PK/PD studies were conducted: a single-dose study (n = 24) and a multiple-dose study (n = 60). In each study, HVs were randomized to Nivestym followed by US-Neupogen, or vice versa. Study drug (5 μg/kg) was administered subcutaneously as a single injection or as five consecutive daily injections. Primary PK and PD endpoints were area under the filgrastim serum concentration-time curve, maximum observed concentration, area under the effect curve (AUEC) for absolute neutrophil count (ANC), maximum observed ANC, AUEC for cluster of differentiation (CD)-34⁺ count, and maximum observed CD34⁺ count. In an open-label, parallel-design, non-inferiority, comparative immunogenicity study, HVs were randomized (n = 128/treatment) to Nivestym or US-Neupogen. The primary endpoint was the proportion of subjects with a negative baseline antidrug antibody (ADA) test result and one or more confirmed post-dose positive ADA result.

RESULTS

Overall demographics were as follows: female (n = 162/340); White (n = 274/340), Black (n = 58/340), and other (n = 8/340); age (18-65 years); and weight (50.8-96.5 kg). All primary PK and PD endpoints met the pre-specified criteria for PK and PD equivalence. The primary endpoint in the comparative immunogenicity study met pre-specified criteria for non-inferiority.

CONCLUSIONS

Nivestym demonstrated PK and PD equivalence in single and multiple subcutaneous-dose settings and non-inferiority for immunogenicity to US-Neupogen, with a comparable safety profile, supporting the demonstration of biosimilarity.

TRIAL REGISTRATION

ClinicalTrials.gov C1121002 (NCT02766647); C1121003 (NCT02766634); C1121012 (NCT02923791).

GP2017, an adalimumab biosimilar: pharmacokinetic similarity to its reference medicine and pharmacokinetics comparison of different administration methods

Background: To compare the pharmacokinetics of Sandoz biosimilar adalimumab (GP2017) with reference adalimumab (Humira) in healthy volunteers (PK similarity study) and to compare the pharmacokinetics of GP2017 administered by autoinjector (AI) or prefilled syringe (PFS; delivery study). Methods: Healthy male subjects were randomized to receive a single 40 mg subcutaneous injection of GP2017, US-licensed or EU-authorized reference adalimumab (US/EU-Humira; PK similarity study) or a single 40 mg subcutaneous injection of GP2017 via AI or PFS (delivery study). Pharmacokinetics, safety, and immunogenicity were assessed over 72 days post-injection. Results: The geometric mean ratios (90% confidence intervals) for C_max and AUC_0-inf were 1.05 (0.99-1.11) and 1.04 (0.96-1.13) for GP2017/EU-Humira and 1.00 (0.94-1.06) and 1.08 (1.00-1.18) for GP2017/US-Humira, all within the prespecified margin of 0.80-1.25 (PK similarity study). Pharmacokinetic parameters of GP2017 matched between AI and PFS (delivery study). Safety and immunogenicity were similar across groups in both studies. Conclusion: PK similarity between GP2017, EU- and US-Humira was demonstrated. The safety profile of GP2017 was consistent with previous reports for Humira. These results contribute to the 'totality-of-the-evidence' supporting biosimilarity of GP2017 to Humira. PK and tolerability were equivalent for GP2017 dosed by AI or PFS. Trial registration: PK similarity study EudraCT no. 2015-000579-28; Delivery study: EudraCT no. 2014-002879-29.