2024 Reference Material Conference

Title: mAb Case Study on Challenges for Bridging Reference Standard Potency during Clinical Phases and Monitoring of its Stability

Abstract: As part reference standard (RS) replacement process, from the interim to the first GMP (RS) or later during development or commercial phase, the bridging of potency raises several challenges to avoid shift or drift in batch release. The following topics will be discussed considering also recent feedbacks from various health authorities:

• Testing design (sample size) to ensure relevant potency determination considering the method variability
• Acceptance criteria for relative potency
• Impact of change of method for relative potency determination (eg from binding ELISA test to a Cell-based assay)

In addition, monitoring the stability of a reference standard in term of its relative potency over its life cycle raises also challenges and concerns from the health authorities

Title: Design and Preparation of Reference Materials to Standardise Biological Activity Measurements

Abstract: Physical reference materials play a vital role in the standardisation of  bioassays and so their design and preparation is critical. Serving as the main producer of International Reference Materials for the WHO over several decades we have wide experience of the manufacture and use of such reference materials across the spectrum of biological assays. Essential points will be discussed concerning the preparation, formulation and lyophilization of reference materials to ensure homogeneity, value assignment and long term stability. Examples of successful reference standards will be presented and pitfalls to avoid in the selection and preparation of in-house reference materials.

Title: An Overview of Analytical Development Activities for Establishing and Maintaining Biologics Reference Standards

Abstract: Biologic reference standards have especial considerations and practices that differ from those applied to small molecule programs, most notably how they are used in relative potency bioassays. In connection with an initial fusion protein development program, the Analytical Development department is tasked with building internal policies and procedures to establish and maintain biological reference standards in support of an oncology pipeline. These reference standards are intended to be implemented at the pre-clinical stage and the type and amount of supportive data grows in complexity parallel to the drug lifecycle during clinical development. The primary biological reference standard, to be used after commercialization of the drug, needs to be traced back to the original standard qualified during pre-clinical development. It is particularly challenging to maintain alignment of the relative potency reference standards throughout development because the process and the potency assay(s) continue to be improved. This presentation provides an overview of the types of analytical activities in place for establishing, bridging, and monitoring the stability of product reference standards necessary to support an internal platform pipeline.

Title: Scientific Considerations for the Lifecycle Management of Vaccine Reference Standards

Abstract: Reference standards are used to calculate test results of relative assays or as acceptance criteria for assay control and are critical to control vaccine quality attributes. Vaccine reference standards are typically biological materials and may undergo confirmation changes or degrade during storage. This makes the appropriate management of reference standards, including International References, critical to ensure that commercial vaccine batches remain comparable to materials shown to be safe and efficacious (or immunogenic) in clinical studies over their shelf-life, and throughout the product’s lifecycle.

However, this is challenging for several reasons. Firstly, the assays used to qualify reference standards (e.g., ELISA, in vivo immunogenicity assay) have inherent variability and this uncertainty is compounded with the qualification of each successive reference standard. Secondly, the potency of a reference standard is typically expressed in arbitrary units (e.g., IU, DU for IPV), which cannot be monitored or verified independently. Finally, some relative assay readouts (e.g., ED₅₀, CCID₅₀), which have been proposed for monitoring reference standards, are too variable to be useful.

Orthogonal methods have been proposed as additional tools to improve stability monitoring of reference standards. However, this approach may not be sufficient if the orthogonal methods use the same reference standard or measure the same quality attribute. Alternatively, the arbitrary unit of a reference standard (e.g., ELISA unit (EU)) can be directly linked to an alternative quality attribute (e.g., protein content) that can be measured accurately and precisely. The assessment of these quality attributes combined can improve the ability to detect a drift or shift in reference standard potency prior to implementation as a replacement.

Given the critical role that reference standards play in the control of vaccines, a well-designed reference standard management system that incorporates additional monitoring tools, is essential to ensure that a product remains comparable throughout its lifecycle.

Title: Building a Foundation for Success: Establishment and Management of Relative Potency Reference Material during Early Development

Abstract: Reference Standards for potency assays play a pivotal role in ensuring biopharmaceutical product efficacy and safety. This talk will provide members of the analytical biopharmaceutical community pharmaceutical professionals with valuable insights and strategies to navigate the complexities of Reference Standards for potency assays effectively in compliance with regulatory expectations. The talk will delve into the challenges and best practices for establishing and managing reference material for relative potency assays during biopharmaceutical product development. Practical insights into the preparation and storage of reference standards will be discussed along with a case study that focuses on the management of the lifecycle of a Reference Standard for a therapeutic monoclonal antibody. Included in the case study will be discussion on how to assign relative potency for a biotherapeutic reference standard and the importance of continuous monitoring of potency assay performance through the use of control charts.

Title: Regulatory Perspectives on Reference Materials for Measuring Potency of Cellular and Gene Therapy Products

Abstract: This presentation will include an overview of FDA’s 2023 draft guidance: Potency Assurance for Cellular and Gene Therapy Products, with a focus on reference materials used in potency assays for cellular and gene therapy products.

Title: Pharmaceutical Reference Standards for Early Phase Bioproduct Clinical Development – Industry Best Practices

Abstract: Reference standard essentials and expectations will be emphasized, for more than their vital role in the execution of bioassay methods the known, certified value for relative comparison to the unknown potency of a test sample. Expectations for bioassay reference standards will be compared to non-bioproduct reference standard sourcing, manufacturing, characterization, or reevaluation testing.

Title: Practical Aspects of Reference Standards in Biosimilar Development

Abstract: The use of international reference standards in bioassays supporting biosimilar programs is in most of the cases not possible, mainly due to unavailability of such standards in the time when the biosimilar development kicks off.  As functional bioassays are important part of guiding technical development, many of these relative methods need to be developed already before availability of the first internally produced biosimilar material, to support setting the critical target quality and understanding structure and function relationship. Originator material is used widely as reference standard in these early phases. However, due to some factors like inherent variability of biologics, availability, stability etc. the use of originator material can raise several questions and impact subsequent development phases. In the workshop the authors will discuss different practical aspects of using originator material as reference, the connected bridging exercise to internal reference standards established at later development stages and its impact on the overall comparative analytical assessment.

Title: Regulatory Perspectives: Reference Materials Used in Vaccine Potency Assays

Abstract: Sponsors of biopharmaceutical products use various analytical tests to ensure the quality of active ingredients and drug products throughout development and manufacturing. Reference standards play a crucial role in calibrating these tests, ensuring product quality, stability, and comparability. Regulatory guidance documents, such as ICH Q6B, Q2(R2), Q14, and Q7A, provide expectations for reference standards used in later phases; however, the scientific principles described in these guidance documents can be applied in a phase-appropriate manner to analytical procedures used during all phases of clinical development. Implementing a robust reference standard program early in product development supports clinical development, bridging studies and product stability, by ensuring a continuous control strategy.

Early or interim reference standards should reflect the clinical manufacturing process, while at later stages, primary standards should be fully qualified, represent the commercial process, and have attributes linked to the clinically qualified material from pivotal studies. In early-phase studies, the focus is predominantly on safety outcomes, however the assays used to measure product quality must be fit for the intended purpose. The analytical control strategy, even early in product development, should include some form of a system suitability test in which the reference standard plays an integral role.

Title: Reference Material Challenges in Biosimilar Development

Abstract: The development of biosimilars requires extensive analytical similarity studies to demonstrate similarity between the biosimilar candidate against the reference medicinal product (RMP). These studies involve various methods to compare biological activity, i.e. potency. Thus, the first standard against which a biosimilar candidate is tested is the RMP.

Independently of the analytical similarity requirements, there is a general quality requirement for all biological products to ensure that their potency is the same from batch to batch. For this purpose, an in-house primary reference is established, against which all subsequent batches are compared.

Finally, various international standards and pharmacopeial monographs are becoming available for some biosimilar candidates.

Care must be taken to fulfil all the regulatory and quality requirements and ideally all the above reference standards are equally potent and can be successfully bridged, but this requires careful planning and consideration.

Title: ‘Potency Comparability’ for Early Clinical Trial Reference Material: What It Is, How To Show It, and How To Maintain It

Abstract: Reference standards for biological products establish both product activity and product identity. A common strategy to create early reference standard that represents clinical material uses (part of) an early clinical lot to make that reference standard. Future product lots that contain the same active compound (or compounds in the same proportions) are ‘biologically similar’ and hence, comparable. Because relative potency estimates from biologically similar samples are expected to be robust to substantial changes in the bioassay(s) [even to different bioassays that respond to the same active compound(s)], relative potency of biologically similar samples is ‘exchangeable’ with dilution. Because statistical similarity in a bioassay does not establish biological similarity, a collection of analytic methods is required to strongly support claims of biological similarity. To maintain comparability it is important to monitor the stability of both the bioassay(s) and the reference standard(s); this should include: multiple reference standards with substantial time overlap, different formulations and storage conditions for some reference standards, substantial stability data with many replicate bioassays early, late, and well after ‘expiry’ from many reference standards, periodic comprehensive analyses that test analysis and stability assumptions, rich and detailed monitoring of the bioassay(s).

Title: Connecting the Dots: Primary and Working Reference Standards for Allogeneic CAR T Cells

Abstract: The strategies for design and use of potency assays for Cell and Gene Therapeutics is a developing story. Originally most of these assays were based upon ‘absolute’ potency. More recently, they have begun to transition to ‘relative’ potency. That shift to relative potency assays is associated with the concurrent need for a reference standard. While the desire and intention are to adopt a classical Primary & Working Reference Standard approach, the support of a cellular allogenic CAR-T therapeutic brings with it unique challenges, including donor-to-donor variability, limited lots sizes, and more. We will discuss a possible solution we have undertaken to address these challenges.

Title: Biosimilar Reference Standards Workshop

Abstract: The development of biosimilar medicines has significantly evolved since the first approval in 2006. This workshop delves into the critical aspects of biosimilar development, emphasizing the distinction between the reference drug product and the in-house reference standard. Key topics covered include the historical context, regulatory expectations, and common challenges, including those for the relative potency evaluation. Real-world case studies underscore the importance of evaluating biosimilarity, considering statistical aspects, and addressing discrepancies between reference and biosimilar drug products.

Join us to gain the knowledge and tools to establish and maintain high-quality reference standard programs, ultimately paving the way for well-characterized and regulatory-compliant biosimilars.

Title: Industry Case Study: Implementing a Reference Standard Control Strategy In A Complex Cell-Based Potency Assay

Abstract: Azimplacel is an amniotic suspension allograft (ASA) comprised of cells derived from amniotic fluid and milled amniotic membrane stored at -80°C in a cryopreservation solution. After more than a decade on the market regulated by FDA as a human cell, tissue, or cellular and tissue-based product (HCT/P) under Section 361 of the Public Health Service Act (PHS Act), azimplacel re-entered development as an Investigational New Drug (IND) in a Phase III trial for the treatment of pain associated with knee osteoarthritis in preparation for submission of a Biologics License Application (BLA). Azimplacel is believed to function by downregulating inflammation, resulting in decreased pain. OI has developed a cell-based assay that measures the potency of azimplacel in downregulating inflammation relative to a pooled positive control (PPC) reference standard. The preparation process and qualification criteria governing the use of PPC were established in the IND relative to the cell-based potency assay’s analytical readout; however, since then, additional work identified an alternate protein readout with enhanced analytical properties that is being proposed to replace the original readout. This talk will focus on the implementation of a 2-tiered reference standard leveraging historical product release data while transitioning to an alternate, analytically superior protein readout.

Title: USP Standards and materials to support Protein based biotherapeutics: A case study with Erythropoietin

Abstract: Erythropoietin (EPO) is a 165 amino acid glycoprotein that promotes erythropoiesis. 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. USP has developed two reference standard to support the both the analytical characterization and bioactivity of EPO. This presentation will review the development and potential uses of these standards and provide a brief overview of standards to support monoclonal antibody based therapeutics.