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.

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.

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 (Imraldi^TM) 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.

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.

Electronic supplementary material

The online version of this article (10.1007/s40259-019-00402-0) contains supplementary material, which is available to authorized users.

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.

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.

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.

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 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.

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.