Dissecting the Most Critical Attribute Responsible for a Change in Relative Potency

• Presenter: Carl Co, Biogen
• Abstract: Changes in the relative potency of a protein therapeutic may not be due to changes of a single product quality attribute. Rather, since therapeutics like monoclonal antibodies are complex mixtures of many variants, multiple quality attributes may contribute to changes in potency. In this talk, we present a case study where a change in relative potency could be due to either changes in N-glycan species, percent aggregation or both. We discuss the Structure Activity Studies that were used to dissect the attribute most responsible for this relative potency change. Finally, we describe the regulatory and experimental strategies we used to compare samples that have different relative potencies.
• (Day 2: Bioassays…All Grown Up Session)

Challenges of Maintaining Commercial Product Assays – QC Perspective!

• Speaker: Bassam Hallis, Public Health England
• Abstract: (Pending)
• (Day 2: Bioassays…All Grown Up Session)

MoA Reflecting Bioactivity Assays for Therapeutic Antibodies That Do Not Follow Classical Immunological Pathways

• Speaker: Ulrike Herbrand, DSc, Charles River
• Abstract: Testing the bioactivity of antibody therapeutics interacting with the T cell signaling can be very challenging. Different approaches are discussed using the example of Ustekinumab.
• (Day 1: Bioassays for Non-Classical Products Session)

Subject Pretreatment vs. Time Point Treatment Variation in ADA Assays: Validity of Normalizing Results to Subject Pretreatment Signals

• Speaker: Cynthia Inzano, Bristol-Myers Squibb
• Abstract: The format for many immunogenicity assays is based on the values of negative or non-neutralizing samples and then inferring, by some pre-determined shift in the negative value, whether a sample is positive or remains negative. While the design of most immunogenicity assays is such that negative samples should not register or give a signal, the reality is often individual samples do give some signal in assays. This is especially true when the assay is a cell-based functional assay designed to measure neutralizing potential of an antibody response. The variation in individual samples in cell-based assays is often due to additional factors (ex. growth factors, cytokines) that are present in samples at different levels and that may affect the biological cascade of the assay in ways outside of the designed drug relevant pathway of the assay. In some cases, with high levels of variability in negative samples, a baseline pre-treatment sample from an individual may be used as a benchmark to assess future responses. This methodology of assessing post-treatment responses against pre-treatment responses may be valid if the variability between individuals is responsible for all sample variation. However, it is also important to verify if individuals not only differ from each other, but also, if samples from the same individual over different time points also varies. We have taken advantage of pre-treatment screening visits to collect multiple samples pre-treatment from the same individuals and compare variation across individuals versus variation across days. In the data we will present, there was much higher variability across days than across individuals, making the possibility of using pre-treatment response baselines an invalid methodology to assess neutralizing potential of anti-drug antibodies in post-treatment samples.
• (Day 1: Assay Development)

Life Cycle Management of a Potency Assay: A Case Study of an Innovative Commercial Strategy and Interdependent Partnership with Quality

• Speaker: Tilanthi Jayawardena, Biogen
• Abstract: A DELPHIA binding assay, developed in 2002 for the release of a commercial drug at Biogen, quantifies the potency of drug substance and drug product material. This test is used for routine testing by the Analytical Development (AD) and Quality Control (QC) groups. As part of lifecycle management of the assay, drivers for method improvement included a high invalid assay rate, analyst fatigue, and lack of efficiency in the assay workflow. Our goals in AD were 1) improve the DELPHIA assay capability and execution through redesign, optimization and automation, and 2) improve assay analysis and create more robust and effective acceptance criteria. In conjunction with Quality, an extensive qualification data set was generated that was used not only to assess method performance, but also to understand assay variability and rectify any discrepancies in training, materials, and equipment. The breadth of the dataset (encompassing different analysts, laboratories, sites, dates, and materials) proved necessary for setting test goalposts and for evaluating performance of the new parameters. Finally, this study enabled our Quality partners to initiate pre-validation studies prior to method transfer and has positioned them well to advance to method validation with minimal additional studies required.
• (Day 2: Bioassays…All Grown Up Session)

Bioassay in Product Life Cycle Management

• Speaker: Xu-Rong Jiang, AstraZeneca
• Abstract: (Pending)
• (Day 2: Bioassays…All Grown Up Session)

Bioassays for Biosimilar Development

• Speaker: Jun Kim, AstraZeneca
• Abstract: (Pending)
• (Day 1: Bioassays for BioSimilars Session)

Development and Qualification of a Characterization Panel to Assess the Biological Activity of Golimumab (Simponi®)

• Presenter: Alex Knorre, Eurofins BioPharma Product Testing GmbH
• Abstract: Golimumab (Simponi®) is a fully human monoclonal IgG1 antibody that inhibits binding of TNFα to its receptor TNFR. We have developed and qualified a panel of 10 characterization assays to assess the biological activity of Golimumab. Qualification results of selected Fab functional activity, Fab binding, Fc functional activity and Fc binding assays employing various readouts will be shown. This panel can be used for data generation for QTPP and clone selection for Golimumab biosimilar molecules and can serve as platform for other therapeutic anti TNFa mAbs.
• (Day 1: Bioassays for BioSimilars Session)

Current Practices and Regulatory Expectations Regarding Cell-Based Potency Assay Validation

• Presenter: Ravindra Kumar, Covance
• Abstract: Cell-based potency assays play a pivotal role in determination of potency and mechanism of action of biological drugs. Special attention is drawn to cell-based assays because many animal-based potency assays are being replaced by cell-based assays and regulatory agencies recommend cell-based assay to support the mechanism of action of biologics. Validation of cell-based potency assay is required to determine fitness for its intended use as potency is a critical quality attribute of biological drugs. Several regulatory and guidance documents are published by the Food and Drug Administration (FDA), the International Committee on Harmonization (ICH), the United States Pharmacopeia (USP), and the European Pharmacopeia (Ph. Eur.) to cover different aspects of bioassay validation. Despite the availability of these documents, often there are questions related to implementation and interpretation of these guidelines. As a CRO, we have extensive experience in a wide variety of cell-based assays and exposure to bioassay validation practices in the biopharmaceutical industry. The presentation will be focused on case studies that illustrate the phase appropriate validation of cell-based assay and examples of implementation of current regulatory guidelines.
• (Day 2: Validation of Bioassays Session)

Developing, Optimizing & Qualifying Bioassays for Biosimilars, Biobetters and Innovator Drugs

• Speaker: Jane Lamerdin, DiscoverX Corporation
• Abstract: An increasing global focus on biologic drugs has highlighted a need for rapid, QC-suitable, mechanism of action (MOA)-based bioassays that can enable swift development of potency and stability testing of innovator and biosimilar drugs. Additionally, for biosimilar drugs it is essential to demonstrate similarity through a functional bioassay, establishing equivalence to the originator. Here, we will present data on the development and qualification of bioassays using the innovator molecules, and applicable for development of biosimilar drugs. Data will be presented on assay design that relies on the native receptor biology and qualification of these assays with the innovator molecules. Finally, these assays have been developed into frozen ready-to-use cells, and data presented will compare the performance of these assays in continuous culture format to the ready-to-use format. In particular, data presented here will touch on assays for drugs such as Insulin, Growth Hormone, Parathyroid Hormone, Liraglutide, Aflibercept, Ranibizumab, Panitumumab and Pertuzumab.
• (Day 1: Bioassays for BioSimilars Session)

Strategic Design For Bioassays

• Speaker: David Lansky, Precision Bioassay
• Abstract: (Pending)
• (Day 2: Bioassays…All Grown Up Session)

Interactive Survey: Use of DOE Studies for Early Assay Development

• Speaker: Laureen Little, Quality Services
• Abstract: (Pending)
• (Day 1: Assay Development Session)

Your Statistician is Your Friend: Perspectives on the Development of a Cross-Species Immunoassay for Use under the Animal Rule

• Speaker: Nancy Niemuth, Battelle
• Abstract: (Pending)
• (Day 1: Assay Development Session)

Right First Time Bioassay Development – Strategies for Developing QC & Validation-Ready Methods the First Time

• Speaker: Jodi Pegg, Pfizer
• Abstract: (Pending)
• (Day 1: Assay Development Session)

A Case Study of an MAb with complex MoA: From Early to Late Stage Potency Assay Selection and Implementation

• Speaker: Kimberly Salvia, Genentech
• Abstract: We present a case study of early to late potency assay selection and implementation for a monoclonal antibody (MAbX) that has a complex mechanism of action. MAbX targets a cell surface protein, and preclinical efficacy in vivo is dependent on Fc binding. In vitro cell-based assays demonstrate possible effector function capabilities of MAbX, but the clinical relevance of these Fc functions is not well-defined from preclinical studies. Given the complexity of the MAbX mechanism of action, we describe the development of a Phase I bridging-binding potency assay that monitors binding to both the Fab and Fc. We then present initial cell-based assay possibilities and challenges that lead to continuation of the Phase I potency assay into CMC Stage C. For MAbX, this approach provides time for locking a robust, appropriate cell-based assay by CMC Stage D.
• Additional Authors:
  Peter Day, Pin Yee Wong
• (Day 1: Bioassays for Non-Classical Products Session)

Fit-for-Purpose Automation for Potency Assays for QC

• Presenter: Kathleen Sampson, Genentech
• Abstract: (Pending)
• (Day 2: Bioassays…All Grown Up Session)

Potency Assay Development and Associated Extended Characterization Strategy of Therapeutic mAb

• Presenter: Tilman Schlothauer, Roche
• Abstract: During the past years, we have collected several examples of profound structure function correlations for IgG- based therapeutic modality development. These insights have been used as the basis for the following Potency Assay strategy. Applying a set of orthogonal cell based and cell free functional assays always provides a deep understanding of the molecule and related critical quality attributes.
• (Day 1: Assay Development Session)

Application of a Novel Potency Assay to Assess the Activity of a Bi-Specific Protein Therapeutic

• Speaker: Deborah Thompson, Aptevo Research & Development
• Abstract: A popular area of therapeutic interest is the use of bispecific molecules to redirect a patient’s immune system to attack an oncology target. To assess this type of molecule, A Redirected T Cell Cytotoxicity (RTCC) assay, utilizing commercially available cell lines, was developed. Assay characterization and the problems encountered during the testing of clinical administration samples below limit of detection for most analytical assays will be discussed.
• (Day 1: Bioassays for Non-Classical Products Session)

A Novel ADCC Bioassay with Improved Sensitivity, Dynamic Range, and Serum Tolerance

• Speaker: Michael Tovey, Euro Diagnostica Biomonitor
• Abstract: (Pending)
• (Day 2: Bioassays…All Grown Up Session)

Validation and Challenges of a Potency Assay to Measure Osteoinduction of rhBMP-2

• Presenters: Danielle Visschedyk and Julia Gliwa, Custom Biologics
• Abstract: Recombinant human bone morphogenetic protein-2 (rhBMP-2) is used to promote spine and long bone fusion and bone defect repair at the site of implantation. rhBMP-2 is an osteoinductive protein, which describes its ability to induce osteoblast differentiation from mesenchymal stem cells. A cell-based potency assay using a murine muscle derived cell line was validated to quantify this osteogenic differentiation, as characterized by the production of alkaline phosphatase. The validation was used to assess intermediate precision, accuracy, range, specificity and dilutional linearity. A second lot of reference standard was also evaluated for accuracy, presenting unique challenges about how to bridge a reference standard that has declined in potency over time. Preliminary work to develop a neutralizing antibody assay based on the cell-based potency assay has successfully demonstrated inhibition of the rhBMP-2 activity using anti-rhBMP-2 antibodies. Work is continuing to address the challenge of natural pre-existing anti-drug antibodies in human serum samples.
• Authors:
  Danielle Visschedyk, PhD, Senior Scientist, Custom Biologics™
  Julia Gliwa, MSc, Associate Scientist, Custom Biologics™
• (Day 2: Validation of Bioassays Session)

Potency Assays – Practical Considerations

• Speaker: Leslie Wagner, FDA
• Abstract: As required by U.S. regulation, an assessment of potency is required for the licensure of the biopharmaceuticals defined in 21 CFR 601.2.
  Ideally, a potency assay should reflect the product’s mechanism of action (MOA), be sensitive to changes in product critical attributes, and stability indicating. The potency test should be validated as per ICH Q2 (R1). In reality, developing a robust, sensitive, and relevant potency assay represents a substantive challenge both in planning and execution.
  Selecting the best potency assay format (i.e., In vivo or in vitro) should be based on scientific knowledge of the product-target interactions, therapeutic effect elicited through the product-target interaction, and the assay performance itself based on the results of the assay’s validation/qualification. System suitability and assay specification acceptance criteria are usually set as a numerical range and should be adjusted throughout the product development to reflect the manufacturing and clinical experience.
  Although many articles have been written on potency assays and their validation, advice is often confusing and contradictory. Assay validation, simply stated, demonstrates that the assay, when performed according to the SOP, is adequately precise and accurate for use in product release and stability studies.
• (Day 2: Opening Session)

The USP Bioassay Chapters: The Honeymoon’s Over?

• Presenter: Steven Walfish, USP
• Abstract: USP Chapters , , , and were last updated nearly ten years ago. The USP Statistics Expert Committee is performing a periodic review of the USP Chapters to determine if there is any new advancement that would make the bioassay chapters more valuable to their stakeholders. This presentation focuses on the USP suite of bioassay chapters. A discussion of the current state, and future plans will be shared with the participants. An open dialogue with participants is expected to gain valuable feedback on areas where the chapters can be improved to be more user-friendly. Do not miss your chance to be part of the change.
• (Day 2: Updates on USP Bioassay Guidances Session)

Inadvertent Consequences of Following a Guideline

• Speaker: Ann Yellowlees, Quantics Biostatistics
• Abstract: We will discuss some inadvertent consequences of the European Pharmacopeia Chapter 5.3 guideline for the statistical analysis of bioassays. This recommends that suitability tests are carried out using a non-parallel model using all the data, including test samples. This means that confidence intervals for reference parameters will be affected by the test sample data and, as a consequence, system suitability tests no longer depend on the reference standard alone, but also on the test samples. We will illustrate the issues that arise with examples and simulations.
• (Day 2: Updates on USP Bioassay Guidances Session)