Development and validation of a cell based assay for the detection of neutralizing antibodies against recombinant insulins

A competitive ligand binding assay for detection of neutralizing antibodies against an insulin analog

Biotherapeutics have the potential to trigger undesired immune responses in the patients. For therapeutic proteins, immunogenicity is manifested as anti-drug antibodies (ADA). Because ADA could compromise pharmacokinetics, efficacy, and safety, regulatory agencies require immunogenicity assessment during clinical development. A tiered bioanalytical approach is recommended to monitor clinical immunogenicity, and neutralizing antibodies (NAb) are studied in Tier 4 if the molecule is immunogenic. Although cell-based assays, which reflect the pharmacological mechanism of action, are in some cases the preferred assay format for detecting NAbs, they are associated with operational complexity and sometimes suboptimal assay performance. Alternatively, non-cell-based assays have also been developed and implemented. In our current study, a competitive ligand binding assay (CLBA) was developed to detect NAbs for insulin efsitora alfa (efsitora, basal insulin Fc, LY3209590), a novel fusion protein being studied for the treatment of Type 1 diabetes and Type 2 diabetes. The CLBA demonstrated acceptable sensitivity, drug tolerance, precision, and robustness, and thus provides a suitable approach for detecting NAbs against efsitora.

Amyloidogenicity of peptides targeting diabetes and obesity

Since the discovery of insulin, a century ago, the repertoire of therapeutic polypeptides targeting diabetes - and now also obesity - have increased substantially. The focus on quality has shifted from impure and unstable preparations of animal insulin to highly pure, homologous recombinant insulin, along with other peptide-based hormones and analogs such as amylin analogs (pramlintide, davalintide, cagrilintide), glucagon and glucagon-like peptide-1 receptor agonists (GLP-1, liraglutide, exenatide, semaglutide). Proper formulation, storage, manipulation and usage by professionals and patients are required in order to avoid agglomeration into high molecular weight products (HMWP), either amorphous or amyloid, which could result in potential loss of biological activity and short- or long-term immune reaction and silent inactivation. In this narrative review, we present perspective of the aggregation of therapeutic polypeptides used in diabetes and other metabolic diseases, covering the nature and mechanisms, analytical techniques, physical and chemical stability, strategies aimed to hamper the formation of HMWP, and perspectives on future biopharmaceutical developments.

Development and Validation of Approach for the Detection of Neutralizing Antibodies Against Insulin (Glargine) in Human Blood Plasma

Introduction. IImmunogenicity identification of therapeutic proteins, such as human insulin analogues, is one of the most relevant and significant area in medicine and pharmaceuticals. Determination the possibility of producing neutralizing antibodies to insulin reducing the therapeutic effect of the drug, is an important step to understand the pharmacological profile of the drug. Applying of cell-based methods one allows to determinate neutralizing antibodies to insulin.

Aim. Development and validation methods for detection of neutralizing antibodies against insulin in human plasma.

Materials and methods. The method is based on the use of the iLiteTM Insulin Assay Ready Cells [1], in the genome of which the firefly luciferase reporter gene is introduced under the control of an insulin-dependent promoter. As the insulin concentration increases, the firefly luciferase expression (Firefly) increases, allowing one to use this cell line to estimate the number of neutralizing antibodies against insulin. For normalization by the number of cells and considering the matrix effect of studied samples, the second reporter gene luciferase Renilla is used, which is expressed under the control of a constitutive promoter. The activity of both luciferases was measured using the DualGlo Luciferase Assay System (Promega) assay [2].

Results and discussion. Optimal insulin concentration and plasma/serum dilution were determined to identify neutralizing antibodies to insulin. The long-term stability of neutralizing antibodies to insulin were shown in human plasma for more than 3 months. The developed method was applied in a comparative research of the safety and immunogenicity of insulin analogues (Glargine). Method for the determination of antibodies to insulin was.

Conclusion. A method for determination of neutralizing antibodies to insulin in human K2EDTA plasma was developed and validated using iLiteTM Insulin Assay Ready Cells system; based on the binding of the insulin alpha chain to the high-affinity heterodimeric CD220 receptor.

Quantification of neutralizing anti-drug antibodies and their neutralizing capacity using competitive displacement and tandem mass spectrometry: Infliximab as proof of principle

Background

The development of anti-drug antibodies (ADA) in patients treated with therapeutic proteins can result in treatment failure. The clinically most relevant fraction of these antibodies are the neutralizing anti-drug antibodies (NAb) that block the pharmacological function of the drug. Consequently, the detection of NAb in plasma is a better predictor of loss of therapeutic response than increased levels of total anti-drug antibodies (ADA) test. Traditional assays to detect ADA and NAb have limited specificity, sensitivity and linear dynamic range.

Method

Here, we demonstrate for the first time the potential of a LC-MS/MS method to measure the concentration of NAb against therapeutic proteins in plasma as exemplified with infliximab (IFX). We designed a competitive screening assay in which the presence of NAb in patients plasma prevents the binding of stable isotopically labeled (SIL) mAb infliximab to TNF-α ligand fixed on a 96-well plate.

Results

After washing, eluting and digesting, the signal intensity of SIL IFX-derived signature peptides was inversely and strongly correlated with NAb concentration in the sample: R² ​= ​0.999. Evaluation data showed that the assay has a high specificity (100%) and a high sensitivity (94%) to predict NAb presence. Cross-validation against total ADA measured by a reference laboratory using radio immunoassay assay (RIA) for ADA provided a good correlation (r² ​= ​0.79).

Conclusion

We developed for the first time a robust and fast screening method on the basis of LC-MS/MS to determine the presence of NAb and its neutralizing capacity in plasma. The analyses of NAb can be combined with therapeutic mAb quantification. Furthermore, the quantification of the neutralizing capacity expressed as mAb mass equivalents opens the door to new personalized dosing strategies in patients with NAb.

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A novel method to quantify neutralizing antibodies and their neutralizing capacity is presented.

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Neutralizing antibodies to infliximab have been determined with liquid chromatography tandem-mass spectrometry.

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Signal of SIL infliximab showed a strong correlation (r² ​= ​0.999) to the concentration neutralizing antibodies in plasma.

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Method was highly specific (100%) and selective (94%) and was well correlated with radioimmunoassay (r² ​= ​0.79).

Comparative immunogenicity assessment of biosimilars

The first anticancer biosimilars have entered clinical use, with many others under clinical development. Like all biologics, biosimilars may elicit unwanted immune responses that can significantly impact clinical efficacy and safety. Head-to-head immunogenicity assessment of biosimilars and their reference biologics should, therefore, be a critical component of a biosimilar's clinical development program. Various bioanalytical platforms may be used to detect and characterize immune responses, each having relative strengths and weaknesses. To fully recognize the clinical relevance of such data, regulators must be able to interpret immunogenicity results in an assay-specific context as well as in perspective of clinical pharmacology, efficacy and safety. Herein, we discuss current challenges imposed by global regulatory requirements for immunogenicity assessment of biosimilars.