The effect of exposure misclassification in spontaneous ADR reports on the time to detection of product-specific risks for biologicals: a simulation study.

BACKGROUND AND OBJECTIVE: The availability of accurate product-specific exposure information is essential in the pharmacovigilance of biologicals, because differences in the safety profile may emerge between products containing the same active substance. In spontaneous adverse drug reaction (ADR) reports, drug exposure may, however, be misclassified, that is, attributed to the incorrect product. The aim of this study was to explore the effect of exposure misclassification on the time to detection of product-specific risks in spontaneous reporting systems. METHODS: We used data simulations to explore the effect of exposure misclassification. We simulated an active substance-specific subset of a spontaneous reporting system and used the proportional reporting ratio for signal detection. The effect of exposure misclassification was evaluated in three test cases representing product-specific ADRs that may occur for biologicals and studied in relative terms by varying the model parameters (market share and relative risk). RESULTS: We found that exposure misclassification results in the largest delay in identification of risks that have a weak association (relative risk < 2 or 3) with the product of interest and in situations where the product associated with the unique risk has a large (>50%) market share. The absolute public health impact of exposure misclassification, in terms of cases/time to detection, varied considerably across the test cases. CONCLUSION: Exposure misclassification in ADR reports may result in a delayed detection of product-specific risks, particularly in the detection of weak drug-event associations. Our findings can help inform the future implementation and refinement of product-specific and batch-specific signal detection procedures.

An analysis of marketing authorisation applications via the mutual recognition and decentralised procedures in Europe.

PURPOSE: The aim of this study is to provide a comprehensive overview of the outcomes of marketing authorisation applications via the mutual recognition and decentralised procedures (MRP/DCP) and assess determinants of licensing failure during CMDh referral procedures. METHODS: All MRP/DCP procedures to the Co-ordination group for Mutual recognition and Decentralised procedures-human (CMDh) during the period from January 2006 to December 2013 were analysed. Reasons for starting referral procedures were scored. In addition, a survey under pharmaceutical companies was performed to estimate the frequency of licensing failure prior to CMDh referrals. RESULTS: During the study period, 10392 MRP/DCP procedures were finalized. Three hundred seventy-seven (3.6%) resulted in a referral procedure, of which 70 (19%) resulted in licensing failure, defined as refusal or withdrawal of the application. The frequency of CMDh referrals decreased from 14.5% in 2006 to 1.6% in 2013. Of all referrals, 272 (72%) were resolved through consensus within the CMDh, the remaining 105 (28%) were resolved at the level of the CHMP. Most referrals were started because of objections raised about the clinical development program. Study design issues and objections about the demonstration of equivalence were most likely to result in licensing failure. An estimated 11% of all MRP/DCP procedures resulted in licensing failure prior to CMDh referral. CONCLUSION: Whereas the absolute number of MRP/DCP procedures resulting in a referral has reduced substantially over the past years, no specific time trend could be observed regarding the frequency of referrals resulting in licensing failure. Increased knowledge at the level of companies and regulators has reduced the frequency of late-stage failure of marketing applications via the MRP/DCP.

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.

Demonstration of Physicochemical and Functional Similarity of the Biosimilar BAT1806/BIIB800 to Reference Tocilizumab.

BACKGROUND AND OBJECTIVE: Tocilizumab is an immunoglobulin G1 monoclonal antibody targeting the interleukin-6 receptor (IL-6R). BAT1806/BIIB800 (tocilizumab-bavi) has been developed as a biosimilar to the reference product tocilizumab (TCZ). The objective of this study was to demonstrate physicochemical and functional similarity between BAT1806/BIIB800 and TCZ in a comprehensive comparability exercise. METHODS: A comprehensive panel of over 20 methods was used to generate datasets comparing critical and non-critical product quality attributes for 10 BAT1806/BIIB800 lots and 44 TCZ lots (16 sourced from China, 16 from the EU, and 12 from the US). Primary structure, higher-order structure, and physicochemical properties were assessed using liquid chromatography, mass spectrometry, various spectroscopy techniques/methods, capillary electrophoresis, and thermoanalytical techniques. Fragment antigen-binding (Fab)- and fragment crystallizable (Fc)-mediated biological properties were assessed using cell-based assays, immunoassays, flow cytometry, and kinetic binding assays. RESULTS: BAT1806/BIIB800 and TCZ (irrespective of source) were shown to be similar in terms of structural and functional properties. No differences were observed in terms of the most critical quality attributes, that is, soluble-IL-6R binding and inhibition of IL-6-mediated cell proliferation. BAT1806/BIIB800 and TCZ demonstrated similarity in terms of Fab- and Fc-mediated binding and biological activity. Minor differences were observed in glycosylation (afucosylation and sialylation), glycation, aggregation, and charge variants, which were demonstrated to be not clinically relevant. CONCLUSION: BAT1806/BIIB800 and TCZ were highly similar for all critical quality attributes. Where differences were observed in less critical quality attributes, additional analytical assessments and clinical study results determined these to be not clinically meaningful.

The role of Periodic Safety Update Reports in the safety management of biopharmaceuticals.

PURPOSE: To describe and assess the outcomes of Periodic Safety Update Report (PSUR) evaluations of biopharmaceuticals. METHODS: A cross-sectional analysis was performed of follow-up requirements of PSURs submitted for centrally approved biopharmaceuticals in the European Union between 1 July 2008 and 30 June 2010. A follow-up analysis on a subset of products that submitted multiple PSURs within the study period was also performed. RESULTS: The cross-sectional analysis included 70 PSURs. Potential safety concerns occurred in 57 (83 %) of all PSURs, and 26 (37 %) concluded a need to change the Summary of Product Characteristics (SPC). In comparison to newer products, products authorized for more than 10 years contained significantly fewer potential safety concerns (60 vs. 92 %; p < 0.01) and required fewer SPC changes (15 vs. 46 %; p = 0.03). For 45 products, multiple PSURs were submitted that could be included in a follow-up analysis. For this subset of products, of the 106 newly identified safety potential safety issues, 7 (7%) resulted in requirements for label changes in the following PSUR. CONCLUSIONS: PSURs facilitate communication between regulators and marketing authorization holders. Potential safety concerns occur for the majority of biopharmaceuticals and throughout their lifecycle, but for established products PSUR evaluations rarely lead to regulatory actions.

Current evidence on the use of the adalimumab biosimilar SB5 (ImraldiTM): a multidisciplinary perspective.

INTRODUCTION: This review provides an overview of data from trials and real-world studies available for SB5 (ImraldiTM) across three main therapeutic areas: rheumatology, gastroenterology, and dermatology. AREAS COVERED: A literature search for publications on data for SB5 efficacy/effectiveness, safety, and immunogenicity was undertaken. EXPERT OPINION: Evidence derived from clinical studies suggest that the biosimilar SB5 is a safe and effective alternative to reference adalimumab. Considering that patients suffering from immune-mediated inflammatory diseases such as inflammatory arthritis, inflammatory bowel disease and psoriasis often require long-term biologic treatment, biosimilar medicines (such as SB5) can reduce healthcare costs while increasing access to effective treatments.

An Introduction to Biosimilars for the Treatment of Retinal Diseases: A Narrative Review.

Biological therapies have revolutionized the treatment of disease across a number of therapeutic areas including retinal diseases. However, on occasion, such treatments may be relatively more expensive compared to small molecule therapies. This can restrict patient access and treatment length leading to suboptimal clinical outcomes. Several biosimilar candidates of ranibizumab and aflibercept are currently in development and the first biosimilar of ranibizumab received EMA approval in August and FDA approval in September 2021. Biosimilars are biological medicines that are highly similar to an already-approved biological medicine (reference product). The physicochemical and clinical similarity of a biosimilar is determined by a rigorous analytical and clinical program, including extensive pharmacokinetic and pharmacodynamic analysis with phase III equivalence studies where appropriate. These phase III studies are carried out in a patient population that is representative of all of the potential approved therapeutic indications of the originator product and the most sensitive for detecting potential differences between the biosimilar and the reference product. Biosimilars have been used successfully across a wide range of therapeutic areas for the past 15 years where they have achieved substantial cost savings that can be reinvested into healthcare systems without affecting the quality of patient care. The current review provides an introduction to biosimilars with the aim of preparing retinal specialists for discussing these products with their patients.

The Efficacy, Safety, and Immunogenicity of Switching Between Reference Biopharmaceuticals and Biosimilars: A Systematic Review.

To date, no consensus exists among stakeholders about switching patients between reference biological products (RPs) and biosimilars, which may have been curbing the implementation of biosimilars in clinical practice. This study synthesizes the available data on switching and assesses whether switching patients from a RP to its biosimilar or vice versa affects efficacy, safety, or immunogenicity outcomes. A total of 178 studies, in which switch outcomes from a RP to a biosimilar were reported, was identified. Data were derived from both randomized controlled trials and real-world evidence. Despite the limitations stemming from a lack of a robust design for most of the studies, the available switching data do not indicate that switching from a RP to a biosimilar is associated with any major efficacy, safety, or immunogenicity issues. Some open-label and observational studies reported increased discontinuation rates after switching, which were mainly attributed to nocebo effects. Involvement of the prescriber in any decision to switch should remain and attention should be paid to the mitigation of a potential nocebo effect.

Batch-to-Batch Consistency of SB4 and SB2, Etanercept and Infliximab Biosimilars.

BACKGROUND: Biosimilars must meet stringent regulatory requirements, both at the time of authorization and during their lifecycle. Yet it has been suggested that divergence in quality attributes over time may lead to clinically meaningful differences between two versions of a biologic. Therefore, this study investigated the batch-to-batch consistency across a range of parameters for released batches of the etanercept biosimilar (SB4) and infliximab biosimilar (SB2). METHODS: SB4 (Benepali®) and SB2 (Flixabi®) were both developed by Samsung Bioepis and are manufactured in Europe by Biogen at their facility in Hillerød, Denmark. A total of 120 batches of SB4 and 25 batches of SB2 were assessed for consistency and compliance with specified release parameters, including purity, post-translational glycosylation (SB4 only), protein concentration, and biological activity. RESULTS: The protein concentration, purity, tumor necrosis factor-α (TNF-α) binding, and TNF-α neutralization of all batches of SB4 and SB2 were within the strict specification limits set by regulatory agencies, as was the total sialic acid (TSA) content of all batches of SB4. CONCLUSIONS: Quality attributes of SB4 and SB2 batches showed little variation and were consistently within the rigorous specifications defined by regulatory agencies.

Are we ready to close the discussion on the interchangeability of biosimilars?

Since the introduction of the first biosimilar the discussion about their interchangeability has persisted. The body of evidence gathered for biosimilars provides reassurance that they are approved based on a rigorous comparability exercise and do not show clinically meaningful differences to their reference products. There are no data suggesting that the risk of switching to a biosimilar in terms of increased immunogenicity is greater than switching between two batches of any biologic. The key concern around switching biosimilars is the nocebo effect, which reinforces the need for physician involvement when switching. Whereas this might argue against automatic substitution of biosimilars, it is not a biosimilars-specific concern. To increase physician confidence in biosimilars, regulators should acknowledge that biosimilars are interchangeable.

Real-World Evidence on Etanercept Biosimilar SB4 in Etanercept-Naïve or Switching Patients: A Systematic Review.

INTRODUCTION: In 2016, SB4 (Benepali®) became the first etanercept (ETN) biosimilar to obtain marketing authorisation in Europe. Despite robust analytical and clinical comparisons, outstanding questions remain on SB4 use in routine practice. METHODS: A systematic search for publications on real-world evidence of SB4 effectiveness, safety and drug survival was undertaken using search terms (SB4 OR Benepali OR biosimilar etanercept OR innovator etanercept) in the BIOSIS® Toxicology, BIOSIS Previews®, Embase® and MEDLINE® databases up to 17 January 2019. RESULTS: Of 959 articles identified, eight journal articles, two journal letters and 23 congress abstracts were selected on criteria of original real-world evidence with a clinical focus. As expected with real-world evidence, quality scoring showed that the evidence had high external validity but lower internal validity. A total of 13,552 patients were described across nine European countries and all approved SB4 indications: 2499 were ETN-naïve and 11,053 switched from reference ETN to SB4 (switchers). Switch acceptance rates (a combination of clinicians offering and patients accepting initiation on SB4) ranged between 51.6% and 99.0%; patient support programmes positively contributed to acceptance. Disease activity was generally similar pre- and post-switch (typically 3-month timeframe). Retention rates across studies were at least 75% (up to 12 months follow-up). No new safety signals were identified. Differences in discontinuation rates versus historic controls reported in some studies may have been influenced by differences in treatment practices, lack of clinician confidence and nocebo effects. CONCLUSION: Nearly 2500 ETN-naïve patients have been initiated on SB4 and outcomes are similar to those patients receiving reference ETN. Overall this systematic review of real-world evidence provides additional reassurance that SB4 is as effective and safe as reference ETN in both switched and naïve patients. FUNDING: Biogen International GmbH.

Controversies in Establishing Biosimilarity: Extrapolation of Indications and Global Labeling Practices.

The principles of establishing biosimilarity are to demonstrate structural and functional similarity to a reference product using the most discriminatory analytical methods. There is still considerable controversy on the scientific basis for extrapolation of indications for biosimilars, which has been strengthened by diverging global regulatory decision making. Closely related to the question of extrapolation is the question of how to communicate the evidence base for authorizing biosimilars to healthcare professionals. In this paper we will consider some of the discussions around extrapolation of indications and the implications of decisions of various regulatory agencies in the world regarding the authorization and labeling of biosimilars.

Characteristics of product recalls of biopharmaceuticals and small-molecule drugs in the USA.

Compared with chemically synthesized small-molecule drugs, the manufacturing process of biopharmaceuticals is more complex. Unexpected changes to product characteristics following manufacturing changes have given rise to calls for robust systems to monitor the postauthorization safety of biopharmaceuticals. We compared quality-related product recalls in the USA of biopharmaceuticals and of small molecules. Although the reasons for recalls for biopharmaceuticals differed from those for small molecules, adverse events were rarely reported. The relative contribution of recalls that could cause serious adverse health consequences was not greater for biopharmaceuticals than for small molecules. Therefore, these data do not give rise to concerns that biopharmaceuticals are more frequently associated with unexpected safety concerns.

Licensing failure in the European decentralised procedure.

The majority of the licensing applications in the European Union are submitted via the decentralised procedure. Little is known about licensing failure (i.e. refusal or withdrawal of a marketing authorisation application) in the EU decentralised procedure compared to the EU centralised procedure and the approval procedure in the United States. The study aim was to determine the frequency of and determinants for licensing failure of marketing authorisation applications submitted via this procedure. We assessed procedures that failed between 2008 and 2012 with The Netherlands as leading authority and assessed the remaining major objections. In total 492 procedures were completed, of which 48 (9.8%) failed: 8 refused, 40 withdrawn. A wide variety of major objections was identified and included both quality (48 major objections) and clinical (45 major objections) issues. The low failure rate may be related to the regular interaction between competent authorities and applicants during the procedure. Some degree of licensing failure may be inevitable, as it may also be affected by the financial feasibility or willingness to resolve major objections, as well as other reasons to withdraw an application besides the raised major objections.

Contribution of animal studies to evaluate the similarity of biosimilars to reference products.

The European Union (EU) was the first region to establish a regulatory framework for biosimilars, in which animal studies are required to confirm similarity to a reference product. However, animal studies described in European public assessment reports (EPARs) or marketing authorization applications (MAAs) did not identify clinically or toxicologically relevant differences despite differences in quality, suggesting that animal studies lack the sensitivity to confirm biosimilarity. Scientific advice provided learning opportunities to evolve existing guidance. Altogether, the data support a step-wise approach to develop biosimilars that focuses on quality and clinical efficacy of biosimilar. This approach might be more effective and does not necessarily require animal studies, which is also reflected in new EU draft guidance.

Biosimilars: in support of extrapolation of indications.

Biosimilars have the potential to lead to enormous cost savings in healthcare without reducing the level of care for patients. In Europe, biosimilars have to demonstrate comparability in an extensive biosimilarity exercise including analytical, preclinical and comparative clinical studies. By successfully completing the biosimilarity exercise, the biosimilar shows that all aspects that are considered relevant for the clinical activity of the product fall within the same range as observed for the innovator. It should be carefully considered whether the benefit of additional information from more comparative clinical studies weighs up to the additional barriers such studies create for biosimilars to enter clinical practice.

Differences between post-authorization adverse drug reactions of biopharmaceuticals and small molecules.

BACKGROUND: The nature of adverse drug reactions observed post-authorization for biopharmaceuticals differs from that observed for chemically synthesized, small molecules (SMs). However, it remains unclear how much of the observed differences can be attributed to differences in authorized indications of the two product groups. OBJECTIVE: To investigate if the nature of adverse drug reactions identified post-authorization for biopharmaceuticals differs from those of SMs within the same anatomical therapeutic chemical (ATC) group. METHODS: We analyzed safety issues included in post-authorization, changes to the Summary of Product Characteristics of centrally approved products in the European Union classified in the ATC main group of 'antineoplastic and immunomodulating agents'. Generics and biosimilars were excluded. All issues identified during 2004-2011 were analyzed for differences in nature and timing between biopharmaceutical and SM products, at different ATC levels. RESULTS: A total of 747 adverse drug reactions were identified; 361 for biopharmaceuticals and 386 for SMs. Within the sub group of immunosuppressants, neoplasms (20 % vs 2 %, p < 0.01) and infections and infestations (22 % vs 9 %, p < 0.01) occurred significantly more frequent for biopharmaceuticals. Adverse drug reactions of SMs were more often renal and urinary disorders (7 % vs 0 %, p < 0.01), blood and lymphatic system disorders (10 % vs 3 %, p = 0.04), and vascular disorders (7 % vs 1 %, p = 0.02). In the subgroup of antineoplastics, immune system disorders occurred more frequently for biopharmaceuticals, (6 % vs 1 %, p = 0.04). With the exception of immune system disorders and renal disorders, the overall differences between biopharmaceuticals and SMs were mostly caused by products authorized as immunosuppressants. For the subset of products authorized after 2004, the median time to the first safety issue was 18 months (95 % CI 12.4-21.5) for biopharmaceuticals and 17 months (95 % CI 12.5-21.5) for SMs and did not differ significantly within subgroups. CONCLUSION: Even within a group of medicinal products approved in the same indication, differences were observed in the nature of adverse drug reactions between biopharmaceuticals and SMs. The considerable differences in the nature of adverse drug reactions between biopharmaceuticals and SMs were not associated with differences in the timing of regulatory actions.

Measures of biosimilarity in monoclonal antibodies in oncology: the case of bevacizumab.

Biosimilars have been available on the European market since 2006 and experience with their use is increasing. The next wave of biopharmaceuticals that are about to lose patent protection consists of more-complicated products, including many monoclonal antibodies. Guidance has been released on the particulars of a biosimilarity exercise involving these products. Considerable challenges exist to establish biosimilarity for anticancer products. An especially challenging product is bevacizumab (Avastin(®)). On the basis of data available for the innovator product (bevacizumab) we will discuss strengths and weaknesses of preclinical and clinical models and explore the application of novel endpoints to the biosimilar comparability exercise.

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.

Effective pharmaceutical regulation needs alignment with doctors.

Concerns emanating from the medical community about the safety and efficacy of biosimilars indicate an increasing distrust of the outcome of the drug regulatory process. To illustrate this, we analysed the creation of the European biosimilar regulatory framework, specifically focussing on the guidelines outlining approval criteria for biosimilar erythropoietins, which have been recently adopted. We observed an absence of the organised medical community in the public process of creating and updating the guidelines. In this article we argue that, to ensure that innovative medicines continue to find their way to the patients who might benefit from them, a closer collaboration between the organised medical community and regulators is needed.