Acceptable changes in quality attributes of glycosylated biopharmaceuticals

Biosimilars of anti-vascular endothelial growth factor for ophthalmic diseases: A review

The development of intravitreally injected biologic medicines (biologics) acting against vascular endothelial growth factor (VEGF) substantially improved the clinical outcomes of patients with common VEGF-driven retinal diseases. The relatively high cost of branded agents, however, represents a financial burden for most healthcare systems and patients, likely resulting in impaired access to treatment and poorer clinical outcomes for some patients. Biosimilar medicines (biosimilars) are clinically equivalent, potentially economic alternatives to reference products. Biosimilars approved by leading health authorities have been demonstrated to be similar to the reference product in a comprehensive comparability exercise, generating the totality of evidence necessary to support analytical, pre-clinical, and clinical biosimilarity. Anti-VEGF biosimilars have been entering the field of ophthalmology in the US since 2022. We review regulatory and scientific concepts of biosimilars, the biosimilar development landscape in ophthalmology, with a specific focus on anti-VEGF biosimilars, and discuss opportunities and challenges facing the uptake of biosimilars.

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.

In situ production and secretion of proteins endow therapeutic benefit against psoriasiform dermatitis and melanoma

Genetic medicines have the potential to treat various diseases; however, certain ailments including inflammatory diseases and cancer would benefit from control over extracellular localization of therapeutic proteins. A critical gap therefore remains the need to develop and incorporate methodologies that allow for posttranslational control over expression dynamics, localization, and stability of nucleic acid-generated protein therapeutics. To address this, we explored how the body's endogenous machinery controls protein localization through signal peptides (SPs), including how these motifs could be incorporated modularly into therapeutics. SPs serve as a virtual zip code for mRNA transcripts that direct the cell where to send completed proteins within the cell and the body. Utilizing this signaling biology, we incorporated secretory SP sequences upstream of mRNA transcripts coding for reporter, natural, and therapeutic proteins to induce secretion of the proteins into systemic circulation. SP sequences generated secretion of various engineered proteins into the bloodstream following intravenous, intramuscular, and subcutaneous SP mRNA delivery by lipid, polymer, and ionizable phospholipid delivery carriers. SP-engineered etanercept/TNF-α inhibitor proteins demonstrated therapeutic efficacy in an imiquimod-induced psoriasis model by reducing hyperkeratosis and inflammation. An SP-engineered anti-PD-L1 construct mediated mRNA encoded proteins with longer serum half-lives that reduced tumor burden and extended survival in MC38 and B16F10 cancer models. The modular nature of SP platform should enable intracellular and extracellular localization control of various functional proteins for diverse therapeutic applications.

A Critical Analysis of the FDA's Omics-Driven Pharmacodynamic Biomarkers to Establish Biosimilarity

Demonstrating biosimilarity entails comprehensive analytical assessment, clinical pharmacology profiling, and efficacy testing in patients for at least one medical indication, as required by the U.S. Biologics Price Competition and Innovation Act (BPCIA). The efficacy testing can be waived if the drug has known pharmacodynamic (PD) markers, leaving most therapeutic proteins out of this concession. To overcome this, the FDA suggests that biosimilar developers discover PD biomarkers using omics technologies such as proteomics, glycomics, transcriptomics, genomics, epigenomics, and metabolomics. This approach is redundant since the mode-action-action biomarkers of approved therapeutic proteins are already available, as compiled in this paper for the first time. Other potential biomarkers are receptor binding and pharmacokinetic profiling, which can be made more relevant to ensure biosimilarity without requiring biosimilar developers to conduct extensive research, for which they are rarely qualified.

Biosimilarity. Do not confuse biosimilar and biocopy. Example of tenecteplase

Non-innovator biological products (NIBPs) or 'biocopies' are available in several countries at lower prices than biosimilars. These drugs, sometimes so-called 'biosimilars', may not meet all of the quality criteria expected of clinically equivalent products. NIBPs can exhibit major differences in physicochemical and pharmacological properties compared with their reference biological but may be presented to prescribers based on clinical trial data and claimed clinical equivalence. Tenecteplase (TNK-tpA) is a recombinant derivative of tissue plasminogen activator, used as a third-generation thrombolytic agent for treatment of acute myocardial infarction. A TNK-tPA presented as biosimilar to the originator (Metalyse®, Boehringer Ingelheim; TNKase®, Roche/Genentech) is now available for use in India (Elaxim®, Gennova Pharmaceuticals). Elaxim® is not approved in Europe or the USA but has been proposed in several countries as a replacement for the originator. Based on available literature, we discuss why this biocopy cannot be considered biosimilar to the originator tenecteplase. We describe clear differences in physicochemical and pharmacological properties. For example, the biocopy demonstrates clot lysis activity that is substantially lower than the originator and contains high concentrations of foreign proteins that confer potential for immunological reactions. Clinical data on the biocopy are limited; randomized trials to demonstrate the absence of difference in efficacy and safety between the biocopy and originator have not been conducted. This example demonstrates that confirmation of similarity, by close examination of pharmaceutical quality attributes, and preclinical and clinical data, is mandatory before presenting to prescribers a biological product as clinically equivalent.

Do the Outcomes of Clinical Efficacy Trials Matter in Regulatory Decision-Making for Biosimilars?

BACKGROUND

There is an increasing body of evidence supporting a more flexible approach in clinical data requirements for the approval of more complex biosimilar substances such as monoclonal antibodies (mAbs).

OBJECTIVE

The aim of this paper is to further analyse the role of quality/chemistry, manufacturing and controls (CMC) and clinical data for the conclusion on biosimilarity and the decision on marketing authorisation (MA).

METHODS

In the present study, we analysed the MA applications (MAAs) of all 33 mAbs and three fusion proteins evaluated by the European Medicines Agency (EMA) between July 2012 and November 2022 with special emphasis on all submitted rituximab (four products) and trastuzumab (seven products) biosimilar candidates, including withdrawn applications. For the two withdrawn applications, the comparative efficacy trials suggested biosimilarity, but the quality/CMC package was not accepted by EMA. We therefore investigated whether a negative MAA outcome could have been predicted based on the evidence generated in the quality/CMC packages, regardless of clinical trial data. For this purpose, we reviewed the respective European Public Assessment Reports (EPARs) or withdrawal assessment reports, and the first regulatory assessments for all these 36 MAAs (i.e. day 120 of the centralized procedure), which are not publicly available. During EMA review, where significant issues are identified which would preclude a marketing authorisation, these issues are raised as questions to the applicant and are classified as major objections (MO).

RESULTS

In 67% of cases, the outcome of the quality and clinical assessment was the same, i.e. both the quality and clinical assessments either supported approval or did not support approval. In 11% of cases, MO were identified in the quality part of the submission but not in the clinical data. In 22% of cases, MO were raised on the clinical data package but not on the quality data. However, we found no instance where seemingly negative clinical data, including failed efficacy trials, led to a negative overall decision. In each instance, the failure to confirm similar clinical performance in all investigated aspects was eventually viewed as not being related to the biosimilar per se but as being due to imbalances in the trial arms, immaturity of secondary endpoint results, change in the reference product, or even chance findings. Furthermore, when performing an in-depth analysis of the quality and clinical packages of trastuzumab and rituximab biosimilars, we found that in no case were clinical trial data necessary to resolve residual uncertainties regarding the quality part.

CONCLUSION

The results further support the argument that sufficient evidence for biosimilarity can be obtained from a combination of analytical and functional testing and pharmacokinetic studies which may also generate immunogenicity data. This calls into question the usefulness of comparative efficacy studies for the purposes of regulatory decision-making when approving biosimilar mAbs and fusion proteins.

Temperature Upshifts in Mammalian Cell Culture: A Suitable Strategy for Biosimilar Monoclonal Antibodies?

Temperature downshifts are the gold standard when setting up control strategies for mammalian cell culture processes. These shifts are performed to prolong production phases and attain heightened levels of productivity. For the development of biosimilars, however, the bottleneck is in achieving a prespecified product quality. In a late-stage development project, we investigated the impact of temperature shifts and other process parameters with the aim of optimizing the glycosylation profile of a monoclonal antibody (mAb). We applied a design of experiments approach on a 3 L scale. The optimal glycosylation profile was achieved when performing a temperature upshift from 35.8 °C to 37 °C. Total afucosylated glycan (TAF) decreased by 1.2%, and galactosylated glycan species (GAL) increased by up to 4.5%. The optimized control strategy was then successfully taken to the manufacturing scale (1000 L). By testing two sets of set points at the manufacturing scale, we demonstrated that the statistical models predicting TAF and GAL trained with small-scale data are representative of the manufacturing scale. We hope this study encourages researchers to widen the screening ranges in process development and investigate whether temperature upshifts are also beneficial for other mAbs.

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

Biosimilars have been available in the USA for over a decade, and in Europe for almost two decades. In that time, biosimilars have become established in the treatment landscape for a wide range of diseases, facilitating patient access and affordability of healthcare. However, patients can still struggle to access biological therapies in some markets. There is a need to streamline the process of developing biosimilars without compromising their quality, safety, or efficacy. This opinion piece considers the efficiencies that could be achieved within the biosimilar approval process. In clinical trials for biosimilars, clinical efficacy endpoints have been shown to be less sensitive measures of biosimilarity than biochemical, biophysical, and biological functional assays. Additional clinical efficacy studies comparing potential biosimilars and reference products do not add information that is useful for regulatory purposes. Large clinical studies of biosimilars with immunogenicity endpoints are of limited value, given the quality control processes in place for all biologics, including biosimilars. The expectation for multiple-switch studies for US interchangeability designation should be reconsidered immediately, and the category should be eliminated in the future. As biosimilars are typically approved globally based on a single set of clinical trials, and all subsequent manufacturing changes are already carefully monitored by regulatory authorities, comparative pharmacokinetic testing of EU and US reference products is unnecessary. Manufacturers and regulators could take greater advantage of existing real-world evidence. Streamlining biosimilar development would enable biosimilar development of more and a wider variety of biological drugs, accelerating biosimilar development without impacting patient safety or effectiveness.

A place for biosimilars in the changing multiple sclerosis treatment landscape

BACKGROUND

The treatment paradigm for multiple sclerosis (MS), particularly relapsing-remitting MS, is heavily reliant on biologic disease-modifying therapies (DMTs). However, the current cost of treatment acts as a significant barrier to access for patients. Over the next few years exclusivity periods for key biologic medicines used in MS are likely to end, opening the door for biosimilar medicines to enter the market.

METHODS

In this review, we discuss what biosimilar medicines are, and how the existing experience with biosimilar medicines across multiple therapy areas can inform the assimilation of biosimilar medicines into the MS treatment landscape in Europe and the US.

RESULTS

There is currently a lack of knowledge and awareness around the distinctions and similarities between small molecules, non-biological complex drugs, and biological medicines, as well as the different categories of follow-on successor medicines. These include biosimilar medicines that offer a matching efficacy and safety profile to the reference biologic. Understanding and recognition of the stringency of the approval pathways required for drug categories such as biosimilars are key in building confidence in treatment outcomes. For example, biosimilar medicines are sometimes perceived only as 'copies' of their reference biologic despite undergoing an extensive approval process requiring that no clinically meaningful differences are observed between the biosimilar medicine and the reference medicine. For MS, introduction of biosimilar medicines in the future will enable more people with MS to receive effective treatment, and also expand access to biologic DMTs in MS. Experiences from the use of biosimilars in multiple therapy areas have shown us that this can result in cost-saving benefits for a healthcare system. Introduction of biosimilar medicines in other therapy areas has also demonstrated the importance of appropriate, accurate education and information for their successful integration into clinical practice.

CONCLUSION

In order to realize optimized treatment outcomes in MS in coming years and to find the appropriate place for biosimilar medicines in the changing MS landscape, it is essential that clinicians and people with MS understand the fundamentals of biosimilars, their potential benefits and consistency of treatment provided by a biosimilar medicine, given the matching efficacy and safety profile to its reference medicine. As evidenced in other therapy areas, biosimilar medicines may reduce key barriers to access by providing a cost-effective alternative to the MS treatment arsenal, while providing the same treatment outcomes as reference biologics.

Real time on-line amino acid analysis to explore amino acid trends and link to glycosylation outcomes of a model monoclonal antibody

Bioreactor parameters can have significant effects on the quantity and quality of biotherapeutics. Monoclonal antibody products have one particularly important critical quality attribute being the distribution of product glycoforms. N-linked glycosylation affects the therapeutic properties of the antibody including effector function, immunogenicity, stability, and clearance rate. Our past work revealed that feeding different amino acids to bioreactors altered the productivity and glycan profiles. To facilitate real-time analysis of bioreactor parameters and the glycosylation of antibody products, we developed an on-line system to pull cell-free samples directly from the bioreactors, chemically process them, and deliver them to a chromatography-mass spectroscopy system for rapid identification and quantification. We were able to successfully monitor amino acid concentration on-line within multiple reactors, evaluate glycans off-line, and extract four principal components to assess the amino acid concentration and glycosylation profile relationship. We found that about a third of the variability in the glycosylation data can be predicted from the amino acid concentration. Additionally, we determined that the third and fourth principal component accounts for 72% of our model's predictive power, with the third component indicated to be positively correlated with latent metabolic processes related to galactosylation. Here we present our work on rapid online spent media amino acid analysis and use the determined trends to collate with glycan time progression, further elucidating the correlation between bioreactor parameters such as amino acid nutrient profiles, and product quality. We believe such approaches may be useful for maximizing efficiency and reducing production costs for biotherapeutics.

Consistency of Product Quality for SB5, an Adalimumab Biosimilar

BACKGROUND

Biologics, regardless of whether they are biosimilars or reference products, are inherently variable due to their size, complexity, and the manufacturing process involved to produce them. Since a drift or evolution of quality attributes of a biologic may impact its clinical safety or efficacy, it is critical for the manufacturer to carefully control the manufacturing process and monitor the quality attributes of a biologic.

OBJECTIVE

The aim of this study was to demonstrate that the quality profile of the SB5 drug product has been consistent over its production history from 2013 to 2022. SB5 is a biosimilar referencing adalimumab (Humira, trademark of AbbVie Biotechnology Ltd) and SB5 has been approved by 14 regulatory authorities including the European Commission in August 2017 (brand name Imraldi™) and the US Food and Drug Administration in July 2019 (brand name Hadlima™).

METHODS

A total of 93 SB5 drug product batches manufactured between 2013 and 2022 were analyzed for a series of release parameters to evaluate the consistency in their critical quality attributes including purity, charge variants, and functional activities (TNF-α binding activity and TNF-α neutralizing potency).

RESULTS

The purity, charge variants, and functional activities of all batches were consistent over time and within the stringent acceptance criteria defined by regulatory agencies to ensure the safety and efficacy of SB5.

CONCLUSION

The data presented in this study provide evidence that the quality of SB5 has remained consistent and tightly controlled even through process changes such as manufacturing site transfers and change in formulation.

Bivalent non-human gal-α1-3-gal glycan epitopes in the Fc region of a monoclonal antibody model can be recognized by anti-Gal-α1-3-Gal IgE antibodies

Monoclonal antibody (mAb) production using non-human cells can introduce non-human glycan epitopes including terminal galactosyl-α1-3-galactose (α1-3-Gal) moieties. Cetuximab is a commercial mAb associated with causing anaphylaxis in some patients due to the binding of endogenous anti-α1-3-Gal IgE to the Fab (containing bi-α1-3-galactosylated glycans) but not to the Fc region (containing mono-α1-3-galactosylated glycans). Despite being low in abundance in typical commercial mAbs, the inherent sensitivity of cell culture conditions on glycosylation profiles, and the development of novel glycoengineering strategies, novel antibody-based modalities, and biosimilars by various manufacturers with varying procedures, necessitates a better understanding of the structural requirements for anti-α1-3-Gal IgE binding to the Fc region. Herein, we synthesized mAb glycoforms with varying degrees and regioisomers of α1-3-galactosylation and tested their binding to two commercial anti-α1-3-Gal human IgE antibodies derived from a human patient with allergies to red meat (comprising α1-3-Gal epitopes), as well as to the FcγRIIIA receptor. Our results demonstrate that unexpectedly, anti-α1-3-Gal human IgE antibodies can bind to Fc glycans, with bi-α1-3-galactosylation being the most important factor, highlighting that their presence in the Fc region may be considered as a potential critical quality attribute, particularly when using novel platforms in mAb-based biotherapeutics.

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.

Microchip electrophoresis separation coupled to mass spectrometry (MCE-MS) for the rapid monitoring of multiple quality attributes of monoclonal antibodies

Therapeutic monoclonal antibodies (mAbs) are highly heterogeneous as a result of posttranslational modifications (PTMs) during bioprocessing and storage. The modifications that impact mAb product quality are regarded as critical quality attributes and require monitoring. The conventional LC-mass spectrometer (MS) method used for product quality monitoring may require protein A purification prior to analysis. In this paper, we present a high-throughput microchip electrophoresis (<4 min) in-line with MS (MCE-MS) that enables baseline separation and characterization of Fc, Fd', and light chain (LC) domains of IdeS-treated mAb sample directly from bioreactor. The NISTmAb was used to optimize the MCE separation and to assess its capability of multiple attribute monitoring. The MCE-MS can uniquely separate and characterize deamidated species at domain level compared to LC-MS method. Two case studies were followed to demonstrate the method capability of monitoring product quality of mAb samples from stability studies or directly from bioreactors.

Comprehensive genetic and functional analyses of Fc gamma receptors influence on response to rituximab therapy for autoimmunity

BACKGROUND

Rituximab is widely used to treat autoimmunity but clinical response varies. Efficacy is determined by the efficiency of B-cell depletion, which may depend on various Fc gamma receptor (FcγR)-dependent mechanisms. Study of FcγR is challenging due to the complexity of the FCGR genetic locus. We sought to assess the effect of FCGR variants on clinical response, B-cell depletion and NK-cell-mediated killing in rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).

METHODS

A longitudinal cohort study was conducted in 835 patients [RA = 573; SLE = 262]. Clinical outcome measures were two-component disease activity score in 28-joints (2C-DAS28CRP) for RA and British Isles Lupus Assessment Group (BILAG)-2004 major clinical response (MCR) for SLE at 6 months. B-cells were evaluated by highly-sensitive flow cytometry. Single nucleotide polymorphism and copy number variation for genes encoding five FcγRs were measured using multiplex ligation-dependent probe amplification. Ex vivo studies assessed NK-cell antibody-dependent cellular cytotoxicity (ADCC) and FcγR expression.

FINDINGS

In RA, carriage of FCGR3A-158V and increased FCGR3A-158V copies were associated with greater 2C-DAS28CRP response (adjusted for baseline 2C-DAS28CRP). In SLE, MCR was associated with increased FCGR3A-158V, OR 1.64 (95% CI 1.12-2.41) and FCGR2C-ORF OR 1.93 (95% CI 1.09-3.40) copies. 236/413 (57%) patients with B-cell data achieved complete depletion. Homozygosity for FCGR3A-158V and increased FCGR3A-158V copies were associated with complete depletion in combined analyses. FCGR3A genotype was associated with rituximab-induced ADCC, and increased NK-cell FcγRIIIa expression was associated with improved clinical response and depletion in vivo. Furthermore, disease status and concomitant therapies impacted both NK-cell FcγRIIIa expression and ADCC.

INTERPRETATION

FcγRIIIa is the major low affinity FcγR associated with rituximab response. Increased copies of the FCGR3A-158V allele (higher affinity for IgG1), influences clinical and biological responses to rituximab in autoimmunity. Enhancing FcγR-effector functions could improve the next generation of CD20-depleting therapies and genotyping may stratify patients for optimal treatment protocols.

FUNDING

Medical Research Council, National Institute for Health and Care Research, Versus Arthritis.

ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR BIOSIMILARS IN OPHTHALMOLOGY

BACKGROUND/PURPOSE

Anti-vascular endothelial growth factor therapies have proven effective in treating retinal diseases but come with a high financial burden to the patient and health care system. Biosimilar drugs present an opportunity to decrease the cost of these important ophthalmic medications, and several ophthalmic biosimilars are expected to be approved and enter the market in the coming years. The objectives of this review are to educate ophthalmologists on the safety and efficacy of biosimilars in ophthalmology in the United States and European Union, review the biosimilar manufacturing and approval process, and describe the upcoming ophthalmic biosimilars.

RESULTS

Two ranibizumab biosimilars are currently approved in the United States and European Union. Additional ranibizumab biosimilars, as well as biosimilars for aflibercept and bevacizumab, are currently in clinical development.

CONCLUSION

Biosimilar use in ophthalmology is expected to grow with the patent expiration of two major anti-vascular endothelial growth factor drugs, ranibizumab and aflibercept, and the development of an ophthalmology-specific bevacizumab biosimilar. Financial savings from biosimilar use in ophthalmology have the potential to reduce economic burden, increase treatment adherence, and ultimately improve health outcomes.

Antibody-dependent cellular cytotoxicity-null effector developed using mammalian and plant GlycoDelete platform

Cancer therapy using immune checkpoint inhibitor antibodies has markedly shifted the paradigm of cancer treatment. However, methods completely eliminating the effector function of these signal-regulating antibodies is urgently required. The heterogeneity of glycan chains in antibodies limits their use as therapeutic agents due to their variability; thus, the development of uniform glycan chains is necessary. Here, we subjected the anti-programmed cell death protein (PD)-1 antibody nivolumab, a representative immune checkpoint inhibitor, to GlycoDelete (GD) engineering to remove the antibody-dependent cellular cytotoxicity (ADCC) of the antibody, leaving only one glycan in the Fc. Glyco-engineered CHO cells were prepared by overexpressing endo-β-N-acetyl-glucosaminidase (Endo T) in CHO cells, in which N-acetyl-glucosaminyl-transferase I was knocked out using Cas9. GD IgG1 nivolumab and GD IgG4 nivolumab were produced using GD CHO cells, and glycan removal was confirmed using mass spectrometry. Target binding and PD-1 inhibition was not altered; however, ADCC decreased. Furthermore, the IgG4 form, determined to be the most suitable form of GD nivolumab, was produced in a plant GD system. The plant GD nivolumab also reduced ADCC without affecting PD-1 inhibitory function. Thus, CHO and plant GD platforms can be used to improve signal-regulating antibodies by reducing their effector function.

Multifunctional NK Cell–Engaging Antibodies Targeting EGFR and NKp30 Elicit Efficient Tumor Cell Killing and Proinflammatory Cytokine Release

In this work, we have generated novel Fc-comprising NK cell engagers (NKCEs) that bridge human NKp30 on NK cells to human epidermal growth factor receptor (EGFR) on tumor cells. Camelid-derived VHH single-domain Abs specific for human NKp30 and a humanized Fab derived from the EGFR-specific therapeutic Ab cetuximab were used as binding arms. By combining camelid immunization with yeast surface display, we were able to isolate a diverse panel of NKp30-specific VHHs against different epitopes on NKp30. Intriguingly, NKCEs built with VHHs that compete for binding to NKp30 with B7-H6, the natural ligand of NKp30, were significantly more potent in eliciting tumor cell lysis of EGFR-positive tumor cells than NKCEs harboring VHHs that target different epitopes on NKp30 from B7-H6. We demonstrate that the NKCEs can be further improved with respect to killing capabilities by concomitant engagement of FcγRIIIa and that soluble B7-H6 does not impede cytolytic capacities of all scrutinized NKCEs at significantly higher B7-H6 concentrations than observed in cancer patients. Moreover, we show that physiological processes requiring interactions between membrane-bound B7-H6 and NKp30 on NK cells are unaffected by noncompeting NKCEs still eliciting tumor cell killing at low picomolar concentrations. Ultimately, the NKCEs generated in this study were significantly more potent in eliciting NK cell–mediated tumor cell lysis than cetuximab and elicited a robust release of proinflammatory cytokines, both features which might be beneficial for antitumor therapy.

Efficacy and safety of biosimilar versus originator infliximab in patients with inflammatory bowel disease: A real-world cohort analysis

BACKGROUND

Anti-tumor necrosis factor (anti-TNF) monoclonal antibody, infliximab, is the primary therapeutic modality for patients with Crohn's disease (CD) and ulcerative colitis (UC), refractory to conventional therapy. Biosimilars of infliximab have been shown to have equivalent efficacy to originator infliximab. We compared the safety and efficacy of infliximab biosimilar with the originator in Indian patients with inflammatory bowel disease (IBD).

METHODS

Patients with IBD treated with either originator or biosimilar infliximab from January 2005 to October 2020 were included in this retrospective analysis. The safety and efficacy of originator or biosimilar infliximab in inducing and maintaining clinical remission at weeks 14 and 52 for CD and UC were evaluated. Disease activity was estimated at baseline, after induction therapy, after 1 year of treatment, and during 12 months of follow-up.

RESULTS

In all, 137 patients (82 CD; 55 UC) were included, of whom 102 were on originator, and 35 patients received biosimilar. In biosimilar group, clinical response and remission rates at weeks 14 and 52 were 84.2%, 58% and 68.4%, 52.6% in CD and 81.2%, 56.2% and 68.7%, 62.5% in UC patients, respectively. Among patients who were on originator, clinical response and remission rates at weeks 14 and 52 were 79.4%, 46% and 57.1%, 43% in CD and 72%, 64.1% and 66.7%, 56.4% in UC patients, respectively. Thirty-three (24.1%) patients experienced adverse events; eighteen developed tuberculosis (TB), of whom 17 received originator and one patient received biosimilar.

CONCLUSIONS

Infliximab biosimilar is comparable to originator infliximab in terms of safety profile and its efficacy in inducing and maintaining remission in patients with IBD.

Relative quantitation of glycans in cetuximab using ultra-high-performance liquid chromatography-high-resolution mass spectrometry by Pronase E digestion

Glycans play important roles in the activity and function of monoclonal antibodies (mAbs). In this study, an isotope labeling method for the relative quantitative analysis of glycans in cetuximab, a chimeric human/mouse IgG1 monoclonal antibody that specifically targets epidermal growth factor receptor, via hydrophilic interaction LC-ultra-high-performance LC-HRMS was established based on Pronase E digestion. To this aim, novel isotope MS probes, i.e., 3-benzoyl-2-oxothiazolidine-4-carboxylic acid (d0-BOTC) and 3-(2,3,4,5,6-pentadeuterio-benzoyl)-2-oxothiazolidine-4-carboxylate acid (d5-BOTC), which include a carboxyl group to target the amino functional group in glycosylamine, were developed. The nonspecific Pronase E enzyme could simultaneously digest the peptide bound to the N- and O-glycans into glycosylamine having only one amino acid. Since the mass difference between the light- and heavy-labeled glycans was 5.0 Da, the relative abundance of their MS peaks was used to achieve the qualitative and relative quantitative analysis of glycans. Sialylglycopeptide was used as a complex glycan model to validate the accuracy of the method. The results demonstrated the good linearity (R² ≥ 0.9994) between the experimentally detected MS intensity ratios and the theoretical molar ratios of the d0-BOTC to the corresponding d5-BOTC derivatives in the dynamic range of 0.03-10 and 0.03-20 of three orders magnitude for the d5-BOTC/d0-BOTC ratios. The reproducibility was between 0.16% and 10.70%, and the limit of detection was 13 fmol. The feasibility of the relative quantification method was investigated by analyzing the glycan content in cetuximab, finding good consistency between experimental and theoretical molar ratios (5:1, 3:1, 1:1, 1:3, 1:5) of d0/d5-BOTC-labeled glycans. Finally, 13 glycans were successfully identified in cetuximab by applying this method using an in-house Tracefinder database. This study provides a novel strategy for the high throughput analysis, identification, and functional study of glycans in mAbs.

Non-Medical Switching in Dermatology: Cost-Conscious Policy or an Affront to Patient Safety?

Non-medical switching is when a patient's therapy is switched for reasons unrelated to health outcomes. Dermatologists are regularly affected by non-medical switching, as many of their complex patients are on expensive medications, which become first-line targets for cost-containment. This commentary examines the literature on non-medical switching and explores the push and pull factors used to drive medication regimen changes. The system-level cost savings of this practice are substantial and could be used to fund treatment for more vulnerable patients. While there is no substantiated evidence of worse outcomes post-switching, patients may suffer negative psychosocial consequences. Negative patient expectations, which are in part fueled by prescriber suspicion of non-medical switching, seem to contribute to this effect. While non-medical switching is not ideal for all patients, it has the potential to reduce cost while maintaining patient outcomes. The decision to switch should be made only after careful evaluation of the individual patient and their physical and psychological reserve.

A review of the totality of evidence supporting the development and approval of a pegfilgrastim biosimilar (LA-EP2006)

OBJECTIVE

The totality-of-evidence approach requires that similarity between a proposed biosimilar and a reference biologic is demonstrated across a range of analytical, preclinical, and clinical parameters to establish biosimilarity. We describe the totality of evidence for Sandoz biosimilar pegfilgrastim (LA-EP2006 [marketed as Ziextenzo]) that supported its regulatory approval in Europe and the United States.

METHODS

Analytical similarity to the reference biologic [marketed by Amgen as Neulasta] was first investigated with regard to physiochemical quality attributes such as primary structure, pegylation, higher-order structures, variants and impurities, molecular size variants, and formulation (protein content, pH, excipients, etc.). In vitro biological activity studies were performed to examine the primary mechanism of action of pegfilgrastim. Bioequivalence (clinical pharmacokinetics [PK] and pharmacodynamics [PD]) of Sandoz biosimilar pegfilgrastim to the reference biologic was studied in healthy volunteers; efficacy, safety, and immunogenicity were assessed during confirmatory clinical efficacy studies in patients undergoing treatment for breast cancer.

RESULTS

No meaningful or relevant differences were identified between Sandoz biosimilar pegfilgrastim and the reference biologic during analytical testing. Similar receptor binding and induction of cellular proliferation in vitro confirmed no functional differences between the biologics. Clinical studies in healthy adult participants demonstrated PK/PD biosimilarity and a similar safety profile between biosimilar and reference pegfilgrastim. Clinical studies in a sensitive patient population also demonstrated similar efficacy, safety, and immunogenicity between Sandoz biosimilar pegfilgrastim and the reference biologic.

CONCLUSIONS

The totality of evidence confirms that Sandoz biosimilar pegfilgrastim matches the reference biologic and will therefore provide equivalent efficacy and safety in all eligible indications.

2021 White Paper on Recent Issues in Bioanalysis: Mass Spec of Proteins, Extracellular Vesicles, CRISPR, Chiral Assays, Oligos; Nanomedicines Bioanalysis; ICH M10 Section 7.1; Non-Liquid & Rare Matrices; Regulatory Inputs (Part 1A - Recommendations on Endogenous Compounds, Small Molecules, Complex Methods, Regulated Mass Spec of Large Molecules, Small Molecule, PoC & Part 1B - Regulatory Agencies' Inputs on Bioanalysis, Biomarkers, Immunogenicity, Gene & Cell Therapy and Vaccine)

The 15th edition of the Workshop on Recent Issues in Bioanalysis (15th WRIB) was held on 27 September to 1 October 2021. Even with a last-minute move from in-person to virtual, an overwhelmingly high number of nearly 900 professionals representing pharma and biotech companies, contract research organizations (CROs), and multiple regulatory agencies still eagerly convened to actively discuss the most current topics of interest in bioanalysis. The 15th WRIB included 3 Main Workshops and 7 Specialized Workshops that together spanned 1 week in order to allow exhaustive and thorough coverage of all major issues in bioanalysis, biomarkers, immunogenicity, gene therapy, cell therapy and vaccines. Moreover, in-depth workshops on biomarker assay development and validation (BAV) (focused on clarifying the confusion created by the increased use of the term "Context of Use - COU"); mass spectrometry of proteins (therapeutic, biomarker and transgene); state-of-the-art cytometry innovation and validation; and, critical reagent and positive control generation were the special features of the 15th edition. This 2021 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop, and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2021 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 1A) covers the recommendations on Endogenous Compounds, Small Molecules, Complex Methods, Regulated Mass Spec of Large Molecules, Small Molecule, PoC. Part 1B covers the Regulatory Agencies' Inputs on Bioanalysis, Biomarkers, Immunogenicity, Gene & Cell Therapy and Vaccine. Part 2 (ISR for Biomarkers, Liquid Biopsies, Spectral Cytometry, Inhalation/Oral & Multispecific Biotherapeutics, Accuracy/LLOQ for Flow Cytometry) and Part 3 (TAb/NAb, Viral Vector CDx, Shedding Assays; CRISPR/Cas9 & CAR-T Immunogenicity; PCR & Vaccine Assay Performance; ADA Assay Comparabil ity & Cut Point Appropriateness) are published in volume 14 of Bioanalysis, issues 10 and 11 (2022), respectively.

Drifts in N-Linked Glycosylation Result in ADCC Potency Variation of Perjeta® from August 2020 to October 2021 in China

The proposed biosimilar candidate needs to demonstrate biosimilarity with reference products, and the quality target product profile and biosimilarity assessment criteria are prerequisite, which should be based on extensive characterization of the reference products. In this study, 13 lots of China-sourced pertuzumab (trademark: Perjeta®), with an expiration date from 2020 to 2021, were comprehensively characterized. Despite the consistency of purity, drifts in N-glycan profile were observed, which resulted in the variation of antibody-dependent cellular cytotoxicity (ADCC) activity. In detail, four parametric curves of ADCC activity of the reference product were unparalleled, and the maximum response value was highly related to the content of %afucose than half-maximal effective concentration (EC₅₀). As ADCC is a potential critical quality attribute of Perjeta®, the glycosylation of Perjeta® and its biosimilars should be tightly monitored and controlled.

Therapeutic antibody glycosylation impacts antigen recognition and immunogenicity

In this study we show that glycosylation is relevant for immune recognition of therapeutic antibodies, and that defined glycan structures can modulate immunogenicity. Concerns regarding immunogenicity arise from the high heterogeneity in glycosylation that is difficult to control and can deviate from human glycosylation if produced in non-human cell lines. While non-human glycosylation is thought to cause hypersensitivity reactions and immunogenicity, less is known about effects of Fc-associated glycan structures on immune cell responses. We postulated that glycosylation influences antigen recognition and subsequently humoral responses to therapeutic antibodies by modulating 1) recognition and uptake by dendritic cells (DCs), and 2) antigen routing, processing and presentation. Here, we compared different glycosylation variants of the antibody rituximab (RTX) in in vitro assays using human DCs and T cells as well as in in vivo studies. We found that human DCs bind and internalize unmodified RTX stronger compared to its aglycosylated form suggesting that glycosylation mediates uptake after recognition by glycan-specific receptors. Furthermore, we show that DC-uptake of RTX increases or decreases if glycosylation is selectively modified to recognize activating (by mannosylation) or inhibitory lectin receptors (by sialylation). Moreover, glycosylation seems to influence antigen presentation by DCs because specific glycovariants tend to induce either stronger or weaker T cell activation. Finally, we demonstrate that antibody glycosylation impacts anti-drug antibody (ADA) responses to RTX in vivo. Hence, defined glycan structures can modulate immune recognition and alter ADA responses. Glyco-engineering may help to decrease clinical immunogenicity and ADA-associated adverse events such as hypersensitivity reactions.

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.

Quality similarity-driven development of biosimilar monoclonal antibodies

The number of approved and marketed biosimilar monoclonal antibodies has been increasing steeply in recent years in regulated markets. In contrast to small molecular generic drugs, structure and variant profile of biosimilar mAbs are not identical with those of the reference medicinal product. Biosimilarity is proven by using the "totality of evidence" approach, and it forms the basis of the approval process of biosimilars in regulated markets. This process includes a comprehensive quality similarity exercise. This step involves the evaluation of all physico-chemical and biological-functional characteristics. The present paper evaluates the analytical similarity approaches taken through the evaluation of quality attributes of recently approved biosimilar mAbs.

Physicochemical and functional characterization of HS016, a biosimilar of adalimumab (Humira)

The characterization of a biosimilar drug HS016, the reference product adalimumab (Humira), and their biosimilarities were determined using physical chemistry and functional similarity tests. The primary and higher order structures, size and charge variants, glycosylation profiles, and in vitro potency of both antibodies were characterized both for unstressed and stability samples. Slight differences were observed in the relative levels of methionine oxidation, low molecular weight components, terminal lysine variant, high mannoses and galactosylated glycans between HS016 and Humira. However, no differences in antigen binding activity, Fc receptor affinity, antibody-dependent cell-mediated cytotoxicity or complemented-dependent cytotoxicity were found. The primary and higher order structures, physicochemical properties, and biological activity of HS016 and adalimumab were similar.

Identifiability of Biologicals: An Analysis Using EudraVigilance, the European Union's Database of Reports of Suspected Adverse Drug Reactions

The relevance of biological therapies for an increasing number of conditions is on the rise. Following the expiry of the initial period of market exclusivity, many of these successful therapies have seen the arrival of biosimilars on the market. The clear identification of the precise medicine responsible for an adverse drug reaction (ADR) report is an important element for pharmacovigilance, allowing timely detection of potential product-specific safety signals. We looked at the identifiability of biologicals up to the level of commercial product name in ADR reports received from European clinical practice between 2011 and December 2019. A good level of identification (91.5%) was observed overall, but at the same time a downward trend was observed in the last 5 years. This reduction in the level of identifiability of biological products (originators and biosimilars) at the commercial name level in general was driven by five widely used substances, whereas the identification of all other biologics stayed consistent over time (at over 90%). We observed that those five substances were used mostly within oncology. The introduction of the first biosimilar in the market did not appear to affect their identifiability. These results show that although the general level of identification at the commercial product name level in ADRs in Europe is robust and generally stable over time, decreasing trends can be down to a few commonly used substances, which need to be monitored to reverse the trend.

Hitting the sweet spot with capillary electrophoresis: advances in N-glycomics and glycoproteomics

N-glycosylation is of paramount importance for understanding the mechanisms of various human diseases and ensuring the safety and efficacy of biotherapeutics. Traditional glycan analysis techniques include LC-based separations and MALDI-TOF-MS identification. However, the current state-of-the-art methods lack throughput and structural information, include laborious sample preparation procedures and require large sample volumes. Capillary electrophoresis (CE) has long been used for the screening and reliable quantitation of glycans, but its applications have been limited. Because of its speed, sensitivity and complementarity with standard glycan analysis techniques, CE is currently emerging as one of the most versatile and adaptable methods for glycan analysis in both academia and industry. Herein, we review the latest advancements in CE-based applications to glycomics and glycoproteomics within both the biopharmaceutical and clinical sectors.

Current status and future prospects for ion-mobility mass spectrometry in the biopharmaceutical industry

Detailed characterization of protein reagents and biopharmaceuticals is key in defining successful drug discovery campaigns, aimed at bringing molecules through different discovery stages up to development and commercialization. There are many challenges in this process, with complex and detailed analyses playing paramount roles in modern industry. Mass spectrometry (MS) has become an essential tool for characterization of proteins ever since the onset of soft ionization techniques and has taken the lead in quality assessment of biopharmaceutical molecules, and protein reagents, used in the drug discovery pipeline. MS use spans from identification of correct sequences, to intact molecule analyses, protein complexes and more recently epitope and paratope identification. MS toolkits could be incredibly diverse and with ever evolving instrumentation, increasingly novel MS-based techniques are becoming indispensable tools in the biopharmaceutical industry. Here we discuss application of Ion Mobility MS (IMMS) in an industrial setting, and what the current applications and outlook are for making IMMS more mainstream.

Comparability of Biologics: Global Principles, Evidentiary Consistency and Unrealized Reliance

The principles of comparability assessments have been accepted globally as offering sensitive and reliable tools with which to evaluate potential changes to biologics that may arise either through processing changes or through the creation of a copy (biosimilar) by a different sponsor. The comparability approach has evolved through systematic advances in four areas: clear and convergent guidelines for evaluation of potential changes to biologics; risk-based systems of weighting analytical data; progressive improvements in analytical methods; and advanced understanding of post-translational modifications. Routine regulatory expectations for clinical equivalence data are being reevaluated, as they seldom contribute to the assessment of similarity. Similarly, we show that requirements to compare biosimilars and locally sourced versions of their reference products are of questionable scientific value and represent a double standard by comparison with the invariable acceptance of the clinical profiles of novel biologics without reference to their sources. The consistent application of evidentiary standards for comparability to all biologics offers an opportunity for regulators to curtail their own assessments of new biosimilars and instead to recognize comparability assessments made in another jurisdiction (reliance), thereby gaining important efficiencies in the regulatory review of biosimilars and improving the competitiveness of the biosimilars market. Such consistency can also enhance the confidence of all stakeholders, especially patients and their providers, in all biologics.

Biosimilars accessible in the market for the treatment of cancer

Biosimilars are the biological product clinically identical to a biologic reference standard regarding their strength, purity, and safety. A large segment of biosimilars has been developed for the treatment of cancer. This review aims to discuss various facets of biosimilars and explicates on biosimilars accessible in the market for cancer clinical intervention. It also illustrates the outcomes of recent clinical trial studies concerning biosimilars. Further, it also crosstalk the safety profiles, regulatory approval requirements, and allied challenges therein. The work will be of significant interest to researchers working in the field of biologics and biosimilars.

Semi-Automated Glycoproteomic Data Analysis of LC-MS Data Using GlycopeptideGraphMS in Process Development of Monoclonal Antibody Biologics

The glycosylation of antibody-based proteins is vital in translating the right therapeutic outcomes of the patient. Despite this, significant infrastructure is required to analyse biologic glycosylation in various unit operations from biologic development, process development to QA/QC in bio-manufacturing. Simplified mass spectrometers offer ease of operation as well as the portability of method development across various operations. Furthermore, data analysis would need to have a degree of automation to relay information back to the manufacturing line. We set out to investigate the applicability of using a semiautomated data analysis workflow to investigate glycosylation in different biologic development test cases. The workflow involves data acquisition using a BioAccord LC-MS system with a data-analytical tool called GlycopeptideGraphMS along with Progenesis QI to semi-automate glycoproteomic characterisation and quantitation with a LC-MS1 dataset of a glycopeptides and peptides. Data analysis which involved identifying glycopeptides and their quantitative glycosylation was performed in 30 min with minimal user intervention. To demonstrate the effectiveness of the antibody and biologic glycopeptide assignment in various scenarios akin to biologic development activities, we demonstrate the effectiveness in the filtering of IgG1 and IgG2 subclasses from human serum IgG as well as innovator drugs trastuzumab and adalimumab and glycoforms by virtue of their glycosylation pattern. We demonstrate a high correlation between conventional released glycan analysis with fluorescent tagging and glycopeptide assignment derived from GraphMS. GraphMS workflow was then used to monitor the glycoform of our in-house trastuzumab biosimilar produced in fed-batch cultures. The demonstrated utility of GraphMS to semi-automate quantitation and qualitative identification of glycopeptides proves to be an easy data analysis method that can complement emerging multi-attribute monitoring (MAM) analytical toolsets in bioprocess environments.

Extrapolation: Experience gained from original biologics

Biologicals undergo modifications throughout their commercial lifecycle. Major changes can unintentionally magnify their inherent physicochemical variability. Although trials comparing the pre- and the post-change versions have been requested occasionally, analytical comparison is the most sensitive approach to anticipating clinical equivalence. Therefore, it may be concluded, by means of 'extrapolation', that non-identical versions of a given biologic will behave equally in all indications. Despite the lessons learned with original biologics, there are still controversies around the approval of biosimilars through extrapolation. Here, a comprehensive analysis of scattered information allows for an account of cases of original biologic versions approved in some indications with no patient trials involved. Healthcare professionals can be reassured that inasmuch as extrapolation has proven valid for new versions of original biologics, the same holds for biosimilars.

The Automatic Substitution of Biosimilars: Definitions of Interchangeability are not Interchangeable

In the USA, an interchangeability designation provides biosimilar sponsors with a pathway for achieving what is standard for small-molecule generics: pharmacy-level auto-substitution for an innovator. No other major health authority links interchangeability to automatic substitution, as all require the involvement of the prescriber or patient in a medication change. This editorial considers the clinical impact and practicality of auto-substitution. First, interchangeability is linked to non-medical switching (NMS), the practice of switching treatment in patients with stable disease for non-clinical reasons. NMS may generate negative sentiment in those unwilling or reluctant to switch, which can adversely impact treatment outcomes (i.e., nocebo effect). Indeed, in real-world studies of tumor necrosis factor inhibitors, discontinuation rates have been shown to be higher in patients switched to biosimilars for non-medical reasons than in historical cohorts maintained on innovators. Second, interchangeability may impede pharmacovigilance and traceability, as not all jurisdictions require innovators and biosimilars to have distinct biologic names. Third, an interchangeability designation from the US Food and Drug Administration only permits a biosimilar to be automatically substituted for its innovator, not other biosimilars (if available). Pharmacist education would be needed to avoid off-label, automatic substitution among biosimilars of a single innovator. Last, once granted, an interchangeability designation exists in perpetuity under current US federal law. However, the supply chains of innovators and biosimilars are maintained independently, with no requirement for reconfirmation of biosimilarity or interchangeability. We feel that additional guidance is needed for the auto-substitution of biosimilars and innovators to become a reality.

The First WHO International Standard for Adalimumab: Dual Role in Bioactivity and Therapeutic Drug Monitoring

The expanded availability of adalimumab products continues to widen patient access and reduce costs with substantial benefit to healthcare systems. However, the long-term success of these medicines is highly dependent on maintaining consistency in quality, safety and efficacy while minimizing any risk of divergence during life-cycle management. In recognition of this need and demand from global manufacturers, the World Health Organization (WHO) Expert Committee on Biological standardization established the WHO 1^st International standard (IS) for Adalimumab (coded 17/236) in October 2019 with a defined unitage ascribed to each of the individual bioactivities evaluated in the study namely, TNF-α binding, TNF-α neutralization, complement dependent cytotoxicity and antibody-dependent cellular cytotoxicity. For development of the IS, two candidate standards were manufactured as per WHO recommendations. Analysis of extensive datasets generated by testing of a common set of samples including the candidate standards by multiple stakeholders including regulatory agencies using their own qualified assays in a large international collaborative study showed comparable biological activity for the tested candidates for the different activities. Use of a common standard significantly decreased the variability of bioassays and improved agreement in potency estimates. Data from this study clearly supports the utility of the IS as an important tool for assuring analytical assay performance, for bioassay calibration and validation, for identifying and controlling changes in bioactivity during life-cycle management and for global harmonization of adalimumab products. In addition, in a separate multi-center study which included involvement of hospital and clinical diagnostic laboratories, the suitability of the adalimumab IS for therapeutic drug monitoring assays was examined by analysis of data from testing of a common blind coded panel of adalimumab spiked serum samples representative of the clinical scenario along with the IS and in-house standards in diverse immunoassays/platforms. Both commercially available and in-house assays that are routinely used for assessing adalimumab trough levels were included. Excellent agreement in estimates for adalimumab content in the spiked samples was observed regardless of the standard or the method with inter-laboratory variability also similar regardless of the standard employed. This data, for the first time, provides support for the extended applicability of the IS in assays in use for therapeutic drug monitoring based on the mass content of the IS. The adalimumab IS, in fulfilling clinical demand, can help toward standardizing and harmonizing clinical monitoring assays for informed clinical decisions and/or personalized treatment strategies for better patient outcomes. Collectively, a significant role for the adalimumab IS in assuring the quality, safety and efficacy of adalimumab products globally is envisaged.

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.

Fc galactosylation follows consecutive reaction kinetics and enhances immunoglobulin G hexamerization for complement activation

Fc galactosylation is a critical quality attribute for anti-tumor recombinant immunoglobulin G (IgG)-based monoclonal antibody (mAb) therapeutics with complement-dependent cytotoxicity (CDC) as the mechanism of action. Although the correlation between galactosylation and CDC has been known, the underlying structure–function relationship is unclear. Heterogeneity of the Fc N-glycosylation produced by Chinese hamster ovary (CHO) cell culture biomanufacturing process leads to variable CDC potency. Here, we derived a kinetic model of galactose transfer reaction in the Golgi apparatus and used this model to determine the correlation between differently galactosylated species from CHO cell culture process. The model was validated by a retrospective data analysis of more than 800 historical samples from small-scale and large-scale CHO cell cultures. Furthermore, using various analytical technologies, we discovered the molecular basis for Fc glycan terminal galactosylation changing the three-dimensional conformation of the Fc, which facilitates the IgG1 hexamerization, thus enhancing C1q avidity and subsequent complement activation. Our study offers insight into the formation of galactosylated species, as well as a novel three-dimensional understanding of the structure–function relationship of terminal galactose to complement activation in mAb therapeutics.

Type and Extent of Information on (Potentially Critical) Quality Attributes Described in European Public Assessment Reports for Adalimumab Biosimilars

Regulatory approval of biosimilars predominantly relies on biosimilarity assessments of quality attributes (QAs), particularly the potentially critical QAs (pCQAs) that may affect the clinical profile. However, a limited understanding exists concerning how EU regulators reflect the biosimilarity assessments of (pC)QAs in European public assessment reports (EPARs) by different stakeholders. The type and extent of information on QAs and pCQAs in EPARs were evaluated for seven adalimumab biosimilars. Seventy-seven QAs, including 31 pCQAs, were classified and assessed for type (structural and functional attributes) and extent (biosimilarity interpretation and/or test results) of information in EPARs. Reporting on the QAs (35–75%) varied between EPARs, where the most emphasis was placed on pCQAs (65–87%). Functional attributes (54% QAs and 92% pCQAs) were reported more frequently than structural attributes (8% QAs and 22% pCQAs). About 50% (4 structural and 12 functional attributes) of pCQAs were consistently reported in all EPARs. Regulators often provided biosimilarity interpretation (QAs: 83% structural and 80% functional; pCQAs: 81% structural and 78% functional) but rarely include test results (QAs: 1% structural and 9% functional and pCQAs: 3% structural and 9% functional). Minor differences in structural attributes, commonly in glycoforms and charge variants, were often observed in adalimumab biosimilars but did not affect the functions and clinical profile. Despite the variability in reporting QAs in EPARs, the minor observed differences were largely quantitative and not essentially meaningful for the overall conclusion of biosimilarity of the seven adalimumab biosimilars.

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 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.

Identification and characterization of a residual host cell protein hexosaminidase B associated with N-glycan degradation during the stability study of a therapeutic recombinant monoclonal antibody product

Host cell proteins (HCPs) are process‐related impurities derived from host organisms, which need to be controlled to ensure adequate product quality and safety. In this study, product quality attributes were tracked for several monoclonal antibodies (mAbs) under the intended storage and accelerated stability conditions. One product quality attribute not expected to be stability indicating is the N‐glycan heterogeneity profile. However, significant N‐glycan degradation was observed for one mAb under accelerated and stressed stability conditions. The root cause for this instability was attributed to hexosaminidase B (HEXB), an enzyme known to remove terminal N‐acetylglucosamine (GlcNAc). HEXB was identified by liquid chromatography–mass spectrometry (LC–MS)‐based proteomics approach to be enriched in the impacted stability batches from mAb‐1. Subsequently, enzymatic and targeted multiple reaction monitoring (MRM) MS assays were developed to support process and product characterization. A potential interaction between HEXB and mAb‐1 was initially observed from the analysis of process intermediates by proteomics among several mAbs and later supported by computational modeling. An improved bioprocess was developed to significantly reduce HEXB levels in the final drug substance. A risk assessment was conducted by evaluating the in silico immunogenicity risk and the impact on product quality. To the best of our knowledge, HEXB is the first residual HCP reported to have impact on the glycan profile of a formulated drug product. The combination of different analytical tools, mass spectrometry, and computational modeling provides a general strategy on how to study residual HCP for biotherapeutics development.

DISCONTINUATION RATES FOLLOWING A SWITCH FROM A REFERENCE TO A BIOSIMILAR BIOLOGIC IN PATIENTS WITH INFLAMMATORY BOWEL DISEASE: A SYSTEMATIC REVIEW AND META-ANALYSIS

BACKGROUND

Biologics have revolutionized the treatment of inflammatory bowel disease (IBD). However, these drugs had a significant influence on treatment-related costs, which resulted in the development of biosimilars.

OBJECTIVE

This systematic review and meta-analysis aimed to evaluate the drug discontinuation rate in the IBD population who switched from originator to biosimilars in real-world switching studies and address potential nocebo effects as reasons for drug discontinuation.

METHODS

Medline (via PubMed), EMBASE, Cochrane Library, and abstract databases of selected congresses were screened for reports of monoclonal antibody (mAb) switching with a minimum post-switch follow-up of >6 months or three infusions. All available information on discontinuation rates was assessed.

RESULTS

A total of 30 observational studies were included, involving 3,594 patients with IBD. Twenty-six studies reported a switch from infliximab to CT-P13, two studies involved a switch to SB2, and switching information was not available in two studies. The discontinuation rates were 8%, 14%, and 21% at 6, 12, and 24 months, respectively. The main reasons for drug discontinuation and their respective risks were: disease worsening (2%), remission (4%), loss of adherence (4%), adverse events (5%), and loss of response (7%). The quality of the evidence ranged from low to very low depending on the outcome analyzed. Subjective symptoms leading to drug discontinuation were infrequently reported, and the nocebo effect was clearly assessed in just one of the included papers.

CONCLUSION

Discontinuation rates following a switch to a biosimilar in patients with IBD increase over time. However, it was not possible to confirm the nocebo effect as a reason for discontinuation. Therefore, long-term studies evaluating the use of biosimilars to monitor adverse events and potential nocebo effects in post-marketing surveillance are still needed.

Comparison of consistency and complementarity of reporting biosimilar quality attributes between regulatory and scientific communities: An adalimumab case study

Biosimilar approval relies on the comparability of quality attributes (QAs), for which information can be derived from regulatory or scientific communities. Limited information is known about whether these sources are consistent with or complementary to each other. The consistency and complementarity of QA reporting in biosimilarity assessments for adalimumab biosimilars approved by the European Medicines Agency in European public assessment reports (EPARs) and scientific publications was assessed. A classification of 77 different QAs (53 structural and 24 functional attributes) was used to assess the types of and information on QAs reported. Six adalimumab biosimilars were analyzed, for which the number of QAs reported in EPARs and publications varied (range = 47 [61%]-60 [78%]). The proportion of QAs consistently reported in both sources varied (range = 28%-75%) among biosimilars; functional QAs (mean = 21 QAs [88%]; range = 19-23) were more consistently reported than structural QAs (mean = 33 QAs [62%]; range = 27-34). The EPARs frequently reported biosimilarity interpretation without providing test results (9-57 QAs in EPARs versus 0-8 QAs in publications), whereas publications frequently reported both test results and interpretations (13-40 QAs in publications versus 0-3 QAs in EPARs). Both sources provided information on the biosimilarity of QAs in a complementary manner and the same biosimilarity interpretation of test results for reported QAs (mean = 90%; range = 78%-100%), with a small discrepancy in biosimilarity interpretations of a few clinically relevant QAs related to post-translation modifications and biological activity. Comprehensive reporting of QAs can contribute to an improved understanding of the role of structural and functional attributes in establishing biosimilarity and the mechanism of action of biological substances in general.

Analysis of Monoclonal Antibody Glycopeptides by Capillary Electrophoresis-Mass Spectrometry Coupling (CE-MS)

Glycosylation is a crucial posttranslational modification (PTM) that might affect the safety and efficacy of monoclonal antibodies (mAbs). Capillary electrophoresis-mass spectrometry (CE-MS) enables the characterization of the primary structure of mAbs. A bottom-up proteomic workflow is designed to provide detailed information about the glycosylation. In this chapter, we describe the validated experimental protocol applied for the characterization and relative quantification of mAbs N-glycosylation at the glycopeptide level.