Reference Standards to Support Quality of Synthetic Peptide Therapeutics.

PURPOSE: Peptides are an important class of therapeutics. Their quality is evaluated using a series of analytical tests, many of which depend on well-characterized reference standards to determine identity, purity, and strength. OBJECTIVE: Discuss approaches to producing peptide reference standards, including vialing, lyophilization, analytical testing and stability studies. METHODS: Case studies are used to illustrate analytical approaches to characterize reference standards, including methods for value assignment, content uniformity, and identity testing. Methods described include NMR, mass spectrometry, and chromatography techniques for identity testing and HPLC and GC methods for assessing peptide content and impurities. RESULTS: This report describes the analytical strategy used to establish peptide reference standard and illustrates how results from multiple labs are integrated to assign a value to the final lyophilized vial. A two-step process for value assignment is described, which uses a mass balance approach to assign a quantitative value to a bulk peptide material. The bulk material is then used as a standard to assign a final value to the vialed material. Testing to confirm peptide identity and to ensure consistency of the vialed material is also described. Considerations for addressing variability, identifying outliers, and implementing stability studies are also presented. CONCLUSION: The methods and case studies described provide a benchmark for best practices in establishing the preparation, analytical testing, handling, and storage of peptide reference standards for the pharmaceutical industry. Some peptide features, such as chiral or isobaric amino acids, may require additional techniques to ensure a full characterization of the peptide reference standard.

USP Reference Standard Monoclonal Antibodies: Tools to Verify Glycan Structure.

The glycan profile is a critical quality attribute for pharmaceutical monoclonal antibodies due to the potential physiological impact of the glycan composition when used as a drug product. Monoclonal antibody reference standards are useful as system suitability samples for glycan profile testing. The development of future glycan profiling techniques could be better evaluated by testing well-characterized reference standards. The USP has introduced monoclonal antibody reference standards (i.e., USP mAb 001 RS, USP mAb 002 RS, and USP mAb 003 RS) with the glycan profiles reported herein that can be used to assess the analytical testing of monoclonal antibody glycan profiles. Comparison of the USP reference standards to other available reference standards (NISTmAb) is presented. The glycan profile of the USP monoclonal antibody reference standards covers a range of glycan species that complements other available reference standards. The USP mAb reference standards are a valuable tool that can be used to verify the glycan structure and provide the system suitability of analytical methods.

A Reference Standard for Analytical Testing of Erythropoietin.

PURPOSE: Erythropoietin (EPO) is a 165 amino acid protein that promotes the proliferation of erythrocytic progenitors. A decrease in endogenous EPO production causes anemia that can be treated with recombinant Human EPO (rHuEPO). OBJECTIVE: To ensure the safety and efficacy of the rHuEPO, manufacturers must use analytical methods to demonstrate similarity across batches and between different products. To do this they need reference standards to validate their equipment and methods. METHOD: We used peptide mapping, size-exclusion chromatography, glycoprofiling, and isoelectric focusing to analyze a rHuEPO reference standard. RESULTS: Characterization demonstrates that our rHuEPO reference standard meets the criteria for quality. CONCLUSION: The rHuEPO reference standard is fit for purpose as a tool for validating system suitability and methods.

Biopharmaceutical Industry Capability Building in India: Report from a Symposium.

The biopharmaceutical industry is evolving with a shift in focus from recombinant proteins and antibodies towards more complex cell and gene therapies. To be competitive globally, biomanufacturers need to focus on aligning with global standards with regard to drug quality, reducing manufacturing failures and delivering drugs to market quickly. Building these capabilities requires a multifaceted approach that includes improvements in operations, quality compliance, and control strategies. To address these needs, the US Pharmacopeia (USP), the Department of Biotechnology (DBT) India, and the Confederation of Indian Industry (CII) held a symposium to discuss the requirements and gaps in the biotechnology and pharmaceutical sectors in India and other developing countries. A panel of experts from academia, manufacturing, and governmental agencies identified several drivers needed for capability building, including a skilled workforce, public-private partnerships, advanced manufacturing technologies, novel biologics, and favorable policies. This article summarizes the recommendations put forward by this panel.

Building trust in the quality of vaccines.

To date, several COVID-19 vaccines have been authorized for the voluntary immunization of adults. The quick availability of multiple vaccines is a good strategy to achieve herd immunity during a pandemic. However, the fast-track development of vaccines during this pandemic has raised concerns regarding the quality, safety, and effectiveness of vaccines. In response, USP organized a roundtable to discuss challenges and to solicit input on ways to build trust in vaccines. Key discussion points included manufacturing capacity, availability of a skilled workforce, and investment in new technologies that would enable the safety and quality of vaccine products. There was also a consensus that a rigorous and transparent clinical trial design is essential for understanding the safety and effectiveness of vaccines.

COVID-19 vaccine platforms: Delivering on a promise?

The emergence of the novel SARS-CoV-2 and COVID-19 has brought into sharp focus the need for a vaccine to prevent this disease. Vaccines have saved millions of lives since their introduction to the public over 200 years ago. The potential for vaccination reached new heights in the mid-20th century with the development of technologies that expanded the ability to create novel vaccines. Since then, there has been continued technological advancement in vaccine development. The resulting platforms provide the promise for solutions for many infectious diseases, including those that have been with us for decades as well as those just now emerging. Each vaccine platform represents a different technology with a unique set of advantages and challenges, especially when considering manufacturing. Therefore, it is essential to understand each platform as a separate product and process with its specific quality considerations. This review outlines the relevant platforms for developing a vaccine for SARS-CoV-2 and discusses the advantages and disadvantages of each.

More comprehensive standards for monitoring glycosylation.

Biologics manufacturers must continually monitor the attachment of carbohydrates, called glycans, to their products, because any variability can impact safety and efficacy. To help the industry meet this challenge, the United States Pharmacopeial Convention (USP) offers glycan reference standards and validated methods for glycoprofiling using high-performance liquid chromatography (HPLC). The industry has recently adopted more advanced technologies for glycan analysis, including ultra-high performance liquid chromatography (UHPLC) and mass spectrometry. In this study, we confirm that USP's glycan reference standards are compatible with UHPLC by demonstrating comparable peak separation and glycan identification to HPLC methods. The improved resolving power and shorter run-times of UHPLC also allowed us to identify many of the minor glycan components present in USP's glycan reference standards. These more comprehensively characterized glycan reference standards will enable manufacturers to assess the micro-heterogeneity that can negatively impact the safety and efficacy of biological products.

Recommendations for Enhancing Quality and Capability of Indian Biopharmaceutical Industry: Summary of a Workshop.

The biopharmaceutical industry is undergoing an evolutionary phase with the rise of advanced manufacturing technologies. The regulatory and customer requirements are shifting towards the development of personalized or targeted medicines. With this changing landscape, industry must evaluate the relevance of quality management systems. Over the past two decades, Indian companies have played a significant role in generating access and reducing costs of medicines. The quality management systems that enable the development and manufacturing of biopharmaceuticals require companies to adapt to regulatory requirements of process development, clinical trials, production, and life cycle management. To better understand the status and potential opportunities to enhance the quality management systems of manufacturing biopharmaceuticals, a workshop was organized by United States Pharmacopeia (USP) and Association of Biotechnology Led Enterprises (ABLE). This paper summarizes the recommendations by the panel and participants of the workshop to industry stakeholders, governance bodies, and policymakers. Following points were proposed to strengthen the culture of quality processes in Indian biopharmaceutical industry: i) Inculcating a culture of quality; ii) Effective training programs on quality processes; iii) Focus on quality beyond compliance; iv) Focus on automation and digitization. v) Enhance processes for pharmacovigilance and product life cycle management. vi) Understanding global regulatory processes.

Do Standards Matter? What is Their Value?

Standards allow us to manage expectations for a diverse range of goods and services across the globe. From coordinating international global telecommunications across 24 different time zones to ensuring access to safe drinking water, standards allow us to work, communicate, collaborate, and live with certain expectations about safety and efficacy. When standards are fit-for-purpose, they raise the quality of products and services without requiring us to think about how that quality is assured. The result is that the successful implementation of standards for certain products can counterintuitively make it easy to overlook their importance when creating policies and regulations for next-generation products, such as generic drugs vis-à-vis biosimilars. Here we review the value of public standards as applied to the pharmaceutical industry. Using case studies, we demonstrate how standards for complex products, such as biologics, can be created and managed to ensure their optimal value to society while minimizing the burden to the industry. We also discuss the sustainability of standard development and whether there is sufficient transparency to maintain their role in the public trust. Finally, we assess the ability of standards to promote access to reasonably priced and high-quality biosimilars while enabling efficient product development and review.

Survey of peptide quantification methods and comparison of their reproducibility: A case study using oxytocin.

USP's peptide reference standards content is typically determined using an HPLC assay against an external standard for which the purity was determined by a mass balance approach. To explore the use of other analytical methods, the USP Biologics Department conducted a multi-laboratory collaborative study. The study determined the inter-laboratory variability for peptide quantitation using the following methods: HPLC assay, quantitative nuclear magnetic resonance (qNMR) spectroscopy, or amino acid analysis (AAA). The three methods were compared with regard to their suitability for quantitation of the nonapeptide oxytocin. In this study, the HPLC assay method using the same peptide bulk material as the standard showed the lowest inter-lab variability. The coefficient of variation (%CV) was calculated without counting the uncertainty associated with the purity assignment of the standard with mass balance. The proton qNMR method is a direct measurement of the peptide against an internal standard, which is not difficult to perform under common laboratory conditions. Because of the simpler operation and shorter analytical time, qNMR as a primary method for peptide reference standard value assignment deserves further exploration.

Cell-Based Therapies Formulations: Unintended components.

Cell-based therapy is the fastest growing segment of regenerative medicine, a field that promises to cure diseases not treated by other small molecules or biological drugs. The use of living cells as the active medicinal ingredient present great opportunities to deliver treatment that can trigger the body's own capacity to regenerate damaged or diseased tissue. Some of the challenges in controlling the quality of the finished cell-therapy product relate to the use of a variety of raw materials including excipients, process aids, and growth promotion factors. The quality of these materials is critical for ensuring the safety and quality of the finished therapeutic products. This review will discuss some of the challenges and opportunities associated with the qualification of excipients as well as that of the ancillary materials used in manufacturing.

Role of public standards in the safety and efficacy of biologic medicines.

In this report, we emphasize the importance of public monographs with reference materials, coupled with careful process and change control and attention to GMPs, as a means of advancing access to good quality, safe, and effective medicines, with emphasis on available and incoming biologic medicines. With adequate control of articles covered by a monograph, these public standards can form the basis for a global public quality platform that covers reference products, non-interchangeable reference products, biosimilars, and interchangeable biosimilars. Working collaboratively with all stakeholders, new approaches allow these public standards to emerge nationally and globally in a timely way. Yet, there are increasing limitations in the availability of public standards for biologic medicines, which may reverse many decades of progress. Solutions are considered in this report.

Biomarkers in the age of omics: time for a systems biology approach.

Limitations to biomarker discovery are not only technical or bioinformatic but conceptual as well. In our attempt to offer a solution, we are highlighting three issues that we think are limiting progress in biomarkers discovery. First, the confusion stemming from the imposition of a pathology-type immunohistochemical marker (IHCM) concept on omics data without fully understanding the characteristics and limitations of IHCMs as applied in clinical pathology. Second, the lack of serious consideration for the scope of disease heterogeneity. Third, the refusal of the biomedical community to borrow from other biological disciplines their well established methods for dealing with heterogeneity. Therefore, real progress in biomarker discovery will be attained when we recognize that an omics biomarker cannot be assigned and validated without a priori data modeling and subtyping of the disease itself to reveal the extent of its heterogeneity, and its omics' clonal aberrations (drivers) underlying its subtypes and pathways' diversity. To further support our viewpoints, we are contributing a novel a systems biology method such as parsimony phylogenetic approach for disease modeling prior to biomarker circumscription. As an analytical approach that has been successfully used for a half of a century in other biological disciplines, parsimony phylogenetics simultaneously achieves several objectives: it provides disease modeling in a hierarchical phylogenetic classification, identifies biomarkers as the shared derived expressions or mutations--synapomorphies, constructs the omics profiles of specimens based on the most parsimonious arrangement of their heterogeneous data, and permits network profiling of affected signaling pathways as the biosignature of disease classes.

No evidence for mouse pancreatic beta-cell epithelial-mesenchymal transition in vitro.

We used cre/loxP-based genetic lineage tracing analysis to test a previously proposed hypothesis that in vitro cultured adult pancreatic beta-cells undergo epithelial-mesenchymal transition (EMT) to generate a highly proliferative, differentiation-competent population of mesenchymal islet "progenitor" cells. Our results in the mouse that are likely to be directly relevant to the human system show that adult mouse beta-cells do not undergo EMT in vitro and that the mesenchymal cells that arise in cultures of adult pancreas are not derived from beta-cells. We argue that these cells most likely originate from expansion of mesenchymal cells integral to the heterogeneous pancreatic islet preparations. As such, these mesenchymal "progenitors" might not represent the best possible source for generation of physiologically competent beta-cells for treatment of diabetes.

The defined combination of growth factors controls generation of long-term-replicating islet progenitor-like cells from cultures of adult mouse pancreas.

Application of pancreatic islet transplantation to treatment of diabetes is severely hampered by the inadequate islet supply. This problem could in principle be overcome by generating islet cells from adult pancreas in vitro. Although it is possible to obtain replicating cells from cultures of adult pancreas, these cells, when significantly expanded in vitro, progressively lose pancreatic-specific gene expression, including that of a "master" homeobox transcription factor Pdx1. Here we show for the first time that long-term proliferating islet progenitor-like cells (IPLCs) stably expressing high levels of Pdx1 and other genes that control early pancreatic development can be derived from cultures of adult mouse pancreas under serum-free defined culture conditions. Moreover, we show that cells derived thus can be maintained in continuous culture for at least 6 months without any substantial loss of early pancreatic phenotype. Upon growth factor withdrawal, the IPLCs organize into cell clusters and undergo endocrine differentiation of various degrees in a line-dependent manner. We propose that our experimental strategy will provide a framework for developing efficient approaches for ex vivo expansion of islet cell mass.

Generation of islet-like hormone-producing cells in vitro from adult human pancreas.

Transplantation of pancreatic islets can provide long-lasting insulin independence for diabetic patients, but the current islet supply is limited. Here we describe a new in vitro system that utilizes adult human pancreatic islet-enriched fractions to generate hormone-producing cells over 3-4 weeks of culture. By labeling proliferating cells with a retrovirus-expressing green fluorescent protein, we show that in this system hormone-producing cells are generated de novo. These hormone-producing cells aggregate to form islet-like cell clusters. The cell clusters, when tested in vitro, release insulin in response to glucose and other secretagogues. After transplantation into immunodeficient, nondiabetic mice, the islet-like cell clusters survive and release human insulin. We propose that this system will be useful as an experimental tool for investigating mechanisms for generating new islet cells from the postnatal pancreas, and for designing strategies to generate physiologically competent pancreatic islet cells ex vivo.

Adult pancreas generates multipotent stem cells and pancreatic and nonpancreatic progeny.

Strategies designed to produce functional cells from stem cells or from mature cells hold great promise for treatment of different cell-degenerative diseases. Type 1 and type 2 diabetes are examples of such diseases. Although different in origin, both involve inadequate cell mass of insulin-producing beta cells, the most abundant cell type of pancreatic islets of Langerhans. Practical realization of such strategies is highly dependent on the elucidation of physiological mechanisms responsible for generation of new beta cells in the pancreas, which at this time are poorly defined. The in vitro differentiation systems allowing generation of new beta cells provide a valuable experimental tool for studying these mechanisms. Few such systems are currently available. In this work, we present an in vitro differentiation system, derived from adult mouse pancreas, capable of generating insulin-producing beta-like cells, which self-organize into islet-like cell clusters (ILCCs) during the course of the culture. Surprisingly, we found that along with the ILCCs, multiple cell types with phenotypic characteristics of embryonic central nervous system and neural crest are also generated. Moreover, several embryonic stem cell-specific genes are induced during the course of these cultures. These results suggest that the adult pancreas may contain cells competent to give rise to new endocrine and neural cells.