Exploring the analytical power of the QTOF MS platform to assess monoclonal antibodies quality attributes

Phage-based delivery systems: engineering, applications, and challenges in nanomedicines

Bacteriophages (phages) represent a unique category of viruses with a remarkable ability to selectively infect host bacteria, characterized by their assembly from proteins and nucleic acids. Leveraging their exceptional biological properties and modifiable characteristics, phages emerge as innovative, safe, and efficient delivery vectors. The potential drawbacks associated with conventional nanocarriers in the realms of drug and gene delivery include a lack of cell-specific targeting, cytotoxicity, and diminished in vivo transfection efficiency. In contrast, engineered phages, when employed as cargo delivery vectors, hold the promise to surmount these limitations and attain enhanced delivery efficacy. This review comprehensively outlines current strategies for the engineering of phages, delineates the principal types of phages utilized as nanocarriers in drug and gene delivery, and explores the application of phage-based delivery systems in disease therapy. Additionally, an incisive analysis is provided, critically examining the challenges confronted by phage-based delivery systems within the domain of nanotechnology. The primary objective of this article is to furnish a theoretical reference that contributes to the reasoned design and development of potent phage-based delivery systems.

Mobile Affinity Selection Chromatography Analysis of Therapeutic Monoclonal Antibodies

Federal regulatory agencies require continuous verification of recombinant therapeutic monoclonal antibody (mAb) quality that is commonly achieved in a two-step process. First, the host-cell proteome and metabolome are removed from the production medium by protein A affinity chromatography. Second, following recovery from the affinity column with an acidic wash, mAb quality is assessed in multiple ways by liquid chromatography-mass spectrometry (LC-MS). However, lengthy sample preparation and the lack of higher-order structure analyses are limitations of this approach. To address these issues, this report presents an integrated approach for the analysis of two critical quality attributes of mAbs, namely titer and relative aggregate content. Integration of sample preparation and molecular-recognition-based analyses were achieved in a single step utilizing an isocratically eluted mobile affinity selection chromatography (MASC) column. MASC circumvents the protein A step, simplifying sample preparation. Within 10 min, (i) mAbs are fluorescently coded for specific detection, (ii) monomers and aggregates are resolved, (iii) the mAb titer is quantified, (iv) relative aggregate content is determined, (v) analytes are detected, and (vi) the column is ready for the next sample. It is suggested herein that this mode of rapid quality assessment will be of value at all stages of discovery (screening, clone selection, characterization), process R&D, and manufacturing. Rapid monitoring of variant formation is a critical element of quality evaluation.

Development of a comprehensive approach for performance evaluation of a quantitative multi-attribute method as a quality control method

The multi-attribute method has been recognized as an elegant quantification tool for post-translational modifications (PTMs) of therapeutic proteins, since it can evaluate several attributes spontaneously and site-specifically. Here, the abundance of PTMs calculated by three different types of formula were compared and there was little difference among the results. For the method evaluation, two different kinds of peptides were used as internal standards (ISs) and one of the IS was used as the "standard peak" to define the signal strength of MS. They are also used for system suitability testing to verify whether the condition or sensitivity of mass spectrometry are high enough to evaluate the minor components by confirming the recovery rate of one IS to the another. This system is beneficial that since we have defined the limit of quantification as a certain ratio to IS, consistent MS intensity is applied as the threshold across all detected peaks.

Multi attribute method implementation using a High Resolution Mass Spectrometry platform: From sample preparation to batch analysis

Quality control of biopharmaceuticals such as monoclonal antibodies (mAbs) has been evolving and becoming more challenging as the requirements of the regulatory agencies increase due to the demanding complexity of products under evaluation. Mass Spectrometry (MS)-based methods such as the multi-attribute method (MAM) are being explored to achieve a deeper understanding of the attributes critical for the safety, efficacy, and quality of these products. MAM uses high mass accuracy/high-resolution MS data that enables the direct and simultaneous monitoring of relevant product quality attributes (PQAs, in particular, chemical modifications) in a single workflow, replacing several orthogonal methods, reducing time and costs associated with these assays. Here we describe a MAM implementation process using a QTOF high resolution platform. Method implementation was accomplished using NIST (National Institute for Standards and Technology) mAb reference material and an in-process mAb sample. PQAs as glycosylation profiles, methionine oxidation, tryptophan dioxidation, asparagine deamidation, pyro-Glu at N-terminal and glycation were monitored. Focusing on applications that require batch analysis and high-throughput, sample preparation and LC-MS parameters troubleshooting are discussed. This MAM workflow was successfully explored as reference analytical tool for comprehensive characterization of a downstream processing (DSP) polishing platform and for a comparability study following technology transfer between different laboratories.

Leveraging rAAV bioprocess understanding and next generation bioanalytics development

Recombinant adeno-associated (rAAV) vector-based gene therapy has been the focus of intense research driven by the safety profile and several recent clinical breakthroughs. As of April 2021, there are two rAAV-based gene therapies approved and more than two-hundred active clinical trials (approximately thirty in Phase III). However, the expected increase in demand for rAAV vectors still poses several challenges. Discussed herein are key aspects related to R&D needs and Chemistry, Manufacturing and Control (CMC) efforts required to attend this growing demand. Authors provide their perspective on strategic topics for rAAV-based therapies success: scalability and productivity; improved safety; increased process understanding combined with development of orthogonal bioanalytics that are able to identify, monitor and control Critical Quality Attributes (CQAs) during bioprocessing.

An evaluation of instrument types for mass spectrometry-based multi-attribute analysis of biotherapeutics

Multi-attribute methods (MAM), based on proteolytic digestion followed by liquid chromatography-mass spectrometry analysis of proteolytic peptides, have gained substantial attention in the biopharmaceutical industry for quantifying a variety of quality attributes for therapeutic proteins. Most MAM developed so far have been based on high-resolution mass spectrometers, due to their superb resolving power to distinguish analyte signals from interferences. Lower-resolution instruments, if demonstrated suitable, may further promote the adoption of the technology due to their low cost, small footprint, and ease of use. In this work, we compared the performance of a high-resolution instrument with a few low-resolution quadrupole-type instruments in quantifying a diverse set of quality attributes in a monoclonal antibody product. Different modes of operation for the quadrupole instruments, including scan mode, selected-ion monitoring and multiple-reaction monitoring, were evaluated. The high-resolution instrument has superb performance, with a quantitation limit of 0.002%. Single-quadrupole instruments in scan mode, on the other hand, provide a quantitation limit of about 1%, which may be fit-for-purpose for many routine MAM applications.

Development and validation of a platform reduced intact mass method for process monitoring of monoclonal antibody glycosylation during routine manufacturing

N-linked glycosylation is a primary source of heterogeneity associated with recombinant monoclonal antibodies and plays a key role in a myriad of drug properties associated with biological function. The glycosylation profile of recombinant monoclonal antibodies is influenced by an array of cell culture inputs which must be carefully controlled in order to engineer the desired glycan distribution. A platform reduced intact mass method applied to monoclonal antibodies has been validated as a quantitative method to monitor the relative mannose-5 level as a surrogate for overall high mannose content in cell culture as a control strategy to ensure product quality and process consistency. The method was shown to be linear, accurate, specific, and precise for an IgG1 and IgG4 mAb allowing relative quantitation of mannose-5 in the range 0.8-11.0% and 1.0-6.2%, respectively. The method can be applied at several stages of the production process from cell culture harvest to drug substance/drug product and is amenable to routine GMP batch testing in a quality control laboratory. Testing upstream during cell culture rather than for product release allows for an earlier assessment of product quality as the glycosylation profile remains unchanged during downstream purification.

Challenges for biosimilars: focus on rheumatoid arthritis

Healthcare systems worldwide are struggling to find ways to fund the cost of innovative treatments such as gene therapies, regenerative medicine, and monoclonal antibodies (mAbs). As the world's best known mAbs are close to facing patent expirations, the biosimilars market is poised to grow with the hope of bringing prices down for cancer treatment and autoimmune disorders, however, this has yet to be realized. The development costs of biosimilars are significantly higher than their generic equivalents due to therapeutic equivalence trials and higher manufacturing costs. It is imperative that academics and relevant companies understand the costs and stages associated with biologics processing. This article brings these costs to the forefront with a focus on biosimilars being developed for Rheumatoid Arthritis (RA). mAbs have remarkably changed the treatment landscape, establishing their superior efficacy over traditional small chemicals. Five blockbuster TNFα mAbs, considered as first line biologics against RA, are either at the end of their patent life or have already expired and manufacturers are seeking to capture a significant portion of that market. Although in principle, market-share should be available, withstanding that the challenges regarding the compliance and regulations are being resolved, particularly with regards to variation in the glycosylation patterns and challenges associated with manufacturing. Glycan variants can significantly affect the quality attributes requiring characterization throughout production. Successful penetration of biologics can drive down prices and this will be a welcome change for patients and the healthcare providers. Herein we review the biologic TNFα inhibitors, which are on the market, in development, and the challenges being faced by biosimilar manufacturers.

Current LC-MS-based strategies for characterization and quantification of antibody-drug conjugates

The past few years have witnessed enormous progresses in the development of antibody-drug conjugates (ADCs). Consequently, comprehensive analysis of ADCs in biological systems is critical in supporting discovery, development and evaluation of these agents. Liquid chromatography-mass spectrometry (LC-MS) has emerged as a promising and versatile tool for ADC analysis across a wide range of scenarios, owing to its multiplexing ability, rapid method development, as well as the capability of analyzing a variety of targets ranging from small-molecule payloads to the intact protein with a high, molecular resolution. However, despite this tremendous potential, challenges persist due to the high complexity in both the ADC molecules and the related biological systems. This review summarizes the up-to-date LC-MS-based strategies in ADC analysis and discusses the challenges and opportunities in this rapidly-evolving field.