Analytical

eBook: Quality By Design for Monoclonal Antibodies — Establishing the Foundations for Process Development, Design Space, and Process Control Strategies

The quality by design (QbD) modernized approach to pharmaceutical development is intended to provide regulatory flexibility, increased development and manufacturing efficiency, and greater room to innovate as well as improve manufacturing processes within defined ranges without obtaining regulatory approval first. QbD is a systematic developmental approach that starts with a clear goal in mind and emphasizes understanding of how variability in both process and materials affects a final product (1). Historically, product quality has been assured either with end-product testing…

Methods on the Move: Addressing Method Transfer Challenges for the Biopharmaceutical Industry

Analytical method transfers are essential components of the current global biotechnology environment. Analytical method transfer can be defined as “a documented process that qualifies a laboratory (the receiving laboratory) to use a validated analytical test procedure that originated in another laboratory (sending laboratory), thus ensuring that the receiving laboratory has the procedural knowledge and ability to perform the transferred analytical procedure as intended” (1). The goal is to ensure that a method continues to perform in the validated state regardless…

Host-Cell Protein Risk Management and Control During Bioprocess Development: A Consolidated Biotech Industry Review, Part 1

Host-cell proteins (HCPs) constitute a significant class of process-related impurities during biologics manufacturing. Due to their potential impact on product quality and efficacy as well as patient safety, the total amount of residual HCP in a biological drug substance generally is considered a critical quality attribute (CQA) that usually needs to be tested for during batch release (1, 2). It is both an “industrywide” common understanding and a regulatory requirement to remove HCPs from biologics to acceptably low levels that…

Development of a Freeze-Dried Ebola-Expressing Adenoviral Vector: Unexpected Findings and Problems Solved

In December 2013, a two-year-old child in Guinea became the first person to be killed by Ebola in the most recent outbreak. In March of the following year, that outbreak was declared in West Africa. By mid-2014, the World Health Organization (WHO) had declared it to be a public health emergency of international concern and urged pharmaceutical companies to accelerate their development of candidate vaccines. At the peak of the outbreak in 2014, more than 1,200 new cases of Ebola…

Rational Design of Liquid Protein Formulations: Application of Biophysical Stability Predictors and Descriptors to Reformulate Biotherapeutics

Successful development of liquid biopharmaceutical formulations requires careful assessment of the biophysical properties of the protein in solution, primarily focused on achieving optimal conformational and colloidal stability of the drug-substance molecule (1–11). It also involves extensive stability studies under stressed conditions. Using state-of-the-art biophysical tools for characterization of developed products, those studies are based on key biophysical descriptors and extended particulate characterization methods (subvisible particles in micro- and nano-size range) to deliver a stable product for market with a shelf…

Statistical Assessments of Bioassay Validation Acceptance Criteria

Analytical linearity as well as assessments of precision and accuracy determine the range for a bioassay (1). USP <1033> recommends comparing confidence intervals (CIs) against target validation acceptance criteria in a bioassay validation exercise, but there are no clear guidelines for determining the criteria (2). Here I address several aspects of a bioassay validation, namely • Linearity (coefficient of determination (R2), slope, and intercept parameters) • Accuracy (%relative bias, %RB) • Precision (percent coefficient of variation, %CV) CIs for the…

eBook: Production of Cell-Line Development and Control of Product Consistency During Cultivation — Myths, Risks, and Best Practices

Health authorities are requesting substantial details from sponsors regarding practices used to generate production cell lines for recombinant DNA–(rDNA) derived biopharmaceuticals. Authorities also are asking for information about the clonality of master cell banks (MCBs) and control strategies to minimize genetic heterogeneity. Such requests are prompted by recent reports indicating “nonclonality” for certain production cell lines. To address these and related issues, the CASSS CMC Strategy Forum on “Production Cell Line Development and Control of Product Consistency During Cell Cultivation:…

The Relationship Between R2 and Precision in Bioassay Validation

Analytical linearity along with assessments of precision and accuracy determine the range for bioassays (1). Practitioners can include coefficient of determination (R2) criteria from a linearity study in the bioassay validation protocol. Herein I illustrate the relationship of R2 to study design and analytical method variation. Overview of the Simple Linear Regression Model Dilutional linearity assesses the “ability (within a given range) of a bioassay to obtain measured relative potencies that are directly proportional to the true relative potency of the…

eBook: Development of a Representative Scale-Down UF/DF Model: Overcoming Equipment Limitations and Associated Process Challenges

Scale-down models (SDM) are physical, small-scale models of commercial-scale unit operations or processes that are used throughout the biopharmaceutical industry for validation studies, commercial deviation investigations, and postapproval process improvements. To support these studies, regulatory guidelines state that SDMs should be representative of the commercial process. For some downstream unit operations such as column chromatography, developing a representative SDM is straightforward because a linear scale-down approach can be used. However, developing a representative SDM for other downstream unit operations such…

Therapeutic IgG-Like Bispecific Antibodies: Modular Versatility and Manufacturing Challenges, Part 2

Monoclonal antibodies (MAbs) are bivalent and monospecific, with two antigen-binding arms that both recognize the same epitope. Bispecific and multispecific antibodies, collectively referred to herein as bispecific antibodies (bsAbs), can have two or more antigen-binding sites, which are capable of recognizing and binding two or more unique epitopes. Based on their structure, bsAbs can be divided into two broad subgroups: IgG-like bsAbs and non–IgG-like bsAbs. We have chosen to focus on the former in this review. Part one provides a…