Downstream Processing

The Downstream Perspective: Putting Product Knowledge to Work Using Technological Innovations

After over a quarter century in the industry — including downstream processing (DSP) and manufacturing directorships at Boehringer Ingelheim and leadership roles in technology development, quality, and manufacturing at Novasep — European consultant Margit Holzer is a recognized expert in downstream processing of biopharmaceutical products. Holding a doctorate in biotechnology from the University of Natural Resources and Applied Life Sciences in Austria, Holzer is familiar to BPI readers as both an author and conference participant (1, 2). And in May…

Discover, Develop, Deliver

Astrea Bioseparations is the only adsorbent supplier that can discover new affinity ligands designed to bind selectively to a molecule of interest or specific impurity, develop efficient purification adsorbents and downstream methods, and deliver industrial-scale adsorbents (up to 1,000-L batch sizes) as loose slurry or in good manufacturing practice (GMP)-ready columns. With over 30 years of experience in development of affinity products and design and manufacture of new custom adsorbents, Astrea Bioseparations is a world leader in its field. The…

Reduce Downstream Processing Costs for MAbs By Switching to a Two-Step Platform

Downstream processing operations make up to 80% of the total costs for processing biotherapeutics. Given the current drive to reduce downstream costs, chromatographers and process engineers will need to streamline processes. Herein, we describe the benefits offered by using Tosoh’s two-step process for purifying monoclonal antibodies (MAbs) and compare that method with the standard industrial process. By combining high-performance protein A capture and a single polishing step on salt-tolerant anion-exchange resin, Tosoh’s approach can reduce downstream costs by 45% and…

Capture of CH1-Containing Bispecific Antibodies: Evaluating an Alternative to Protein A

Bispecific antibodies (BsAbs) are designed to recognize and bind two different antigens, in many cases for the purpose of immune effector-cell activation to destroy cancer cells (1). Such BsAbs mediate cell killing by binding simultaneously to an antigen that is overexpressed on tumor cells and to the CD3 receptor, activating cytotoxic T lymphocytes (2). Using proprietary UniRat human heavy-chain technology combined with OmniFlic human fixed–light-chain antibody technology licensed from Ligand Pharmaceuticals, Teneobio has produced several bispecific antibodies, each targeting a…

Dynamic Binding Capacities of Protein A Resins for Antibody Capture: A Comparative Evaluation

The dynamic binding capacity (DBC) of a chromatography resin represents the total amount of target protein that the resin will bind under actual flow conditions before significant breakthrough of unbound protein occurs. This is a useful parameter for predicting what the process performance of a resin will be in actual use. DBC affects the overall amount of resin that can be packed in a given column for a process — and the number of batches that can be processed cost-effectively…

A Challenge in Viral Clearance Determination: Estimation of Fifty-Percent Tissue Culture Infective Dose (TCID50) for Low Virus Concentrations

Performing viral clearance studies is an important safety element of manufacturing all biopharmaceuticals expressed from mammalian cells (1). Typically, viral clearance is described as a log reduction value (LRV) and calculated as the log10 of the ratio of input to output virus load. Amounts of virus load are calculated from the volume and concentration of input and output fractions. Virus concentration is often calculated as 50% of tissue-culture infective dose (TCID50) using the Spearman–Kärber (SK) equation (2, 3). In this…

Setting a Cornerstone for Platform Purification of Exosomes

Exosomes are a subject of rapidly growing therapeutic interest in the biopharmaceutical industry for two principal reasons. The first reason is that they are the primary communicators of instructions from source cells to target cells. Exosome surface features define their destination. They recognize complementary features on target cells, dock with them, and deliver their programmed instructions in the form of microRNA. The second reason is that exosomes are immunologically silent. As normal human cell products, and by contrast with gene…

A Response Plan for Viral Contamination in Bioproduction Facilities

The biopharmaceutical industry uses living biological systems as a platform for manufacturing of protein-based drugs, vaccines, and other therapies derived from or consisting of different cell types. On one hand, living systems are inherently susceptible to viral infection and may harbor endogenous viruses, so the potential for such contamination cannot be eliminated. On the other hand, the industry has an excellent patient-safety record. Viral safety is achieved through three fundamental measures: prevention (e.g., by selection), removal (by clearance and/or reduction),…

Detection and Clearance of Viruses in the Biopharmaceutical Industry

Viral contamination is a common threat to all animal- and human-derived biopharmaceuticals. This type of contamination can affect any part of a bioproduction process, so biomanufacturers need to perform viral testing studies and incorporate viral clearance methods into their processes. Viral contaminants can come from cell lines (e.g., endogenous retroviruses) or from adventitious (e.g., mycoplasma) introduction during drug manufacturing. Virus testing of master cell banks (MCBs), working cell banks (WCBs), end-of-production cell banks, and bulk unprocessed harvest material is called…

Monoclonal Antibody Aggregate Polish and Viral Clearance Using Hydrophobic-Interaction Chromatography

Hydrophobic Interaction chromatography (HIC) is a powerful polishing tool for the downstream purification and manufacture of biotherapeutics. HIC offers orthogonal selectivity for the clearance of difficult process and product-related impurities such as aggregates, host cell proteins and endogenous and adventitious viruses.  In this study, a family of POROS HIC resins with novel ethyl and benzyl chemistries was used to successfully polish two clinical stage monoclonal antibodies harboring very high levels of product aggregation (>10%). In addition to aggregate removal, viral…